—Charles K. Alexander, Professor, Electrical and Computer Engineering, Fenn College of Engineering, Cleveland State University(Alexander, C & Sadiku, M 2009, Fundamentals of Electric-Circuits, 4^th edn. Mcgraw-Hill)

Engineers are trained to solve real life technical problems and communication holds a significant role in doing so. Through technical reports and presentations, engineers communicate with different interested groups.  To enhance professionalism and to promote communication skills among the would-be engineers, ChemicalBUET Group, the largest online congregation of Chemical Engineers of Bangladesh University of Engineering and Technology (BUET), organized a workshop on May 3-4, 2013 at the Department of Chemical Engineering, BUET.

The workshop titled ‘Technical Writing and Presentation’ was designed for the students from the senior years who are on the verge of becoming professionals. Dr. Mohidus Samad Khan, a promising young Bangladeshi researcher currently working in McGill University, conducted the two day long workshop containing four modules.

Module 1 covered general aspects of technical writing, addressing critical issues and common errors of writing technical reports, classification and differences between different types of articles – scientific articles, review articles, short communications, letters, and news articles. The instructor explained the necessity of proper referencing and the negative aspects of plagiarism in technical and scientific writing. Participants were also introduced to the different referencing software out there.

Module 2 was solely based on Journal Publication, its necessity, types, impact factor, general guidelines and standard approach for publication in a journal. The fact that- ‘Conducting an excellent research is all that matters, Publications are its logical consequences’ was well explained and established in this module.

Module 3, the richest of all in terms of content, included discussions on Patents, Conferences and Thesis Writing.

Besides the general explanations of the contents of Module 3, different contemporary critical patent cases were shed light upon.

Tips for facing the Question-Answer sessions at a Conference and strategies for preparing a well-written Thesis-Paper Work were shared in this module.

It is a common scene among senior year students trying to figure out which grad schools to apply to and how to apply for funds. To ease out the dilemma, Module 4 of the workshop was based on the University Ranking, Admission and Scholarship.  Parameters and methodologies of the different ranking systems including QS World University Ranking, Times Higher Education World Reputation Rankings, Academic Rankings of World Universities and Webometrics, along with National Ranking systems of Canada, USA and Australia were discussed in Module 4. Limitations of different ranking systems were also discussed in this module.

The module also explained the importance of publications for admission and scholarship application. At the end of the workshop, an evaluation was conducted; recommendations were also suggested by the attendees.

The workshop aroused a sense of awareness among the attendees, who are the future Chemical Engineers, and its success is marked by the participants who are now better educated and confident. Their appreciation is easily understood from the words they shared during the feedback session. “The workshop has been very useful. Now I can use smart tricks to prepare a better technical report,” said Hasib Al Mahbub, a third year student. Raka Islam, a student from the graduating batch said, “I liked the session on Technical Presentation most. The tips on slide preparation and facing Question-Answer session are marvelous.”  Unaiza Mannan, another participant from the graduating batch shared, “Many of us intend to pursue graduate studies from internationally renowned universities. This workshop dealt with many such issues regarding graduate admissions; I appreciate the initiative.”

The workshop came to an end with the distribution of certificates and a big fat photo session of workshop participants, volunteers and the instructor.

Workshop Evaluation

Number of students participated in the Workshop = 52; Number of students participated in the Workshop Evaluation = 48

Email: mohin27@yahoo.com

Received 28 April 2012; received in revised form 30 September 2012; online published 1 October 2012

Abstract: Hazardous and other waste materials are no longer considered as mere waste, but are treated as valuable resources. Other than generating electricity or preparing manure by processing waste materials, these wastes can be co-processed as alternative fuel or alternative raw material, or in both forms in the resource intensive industries, like cement, steel etc. Only thing that counts is maintaining a number of prescribed process requirements.

Introduction

Resource-intensive industries, nowadays, involve the use of waste in manufacturing processes for the purpose of resource recovery and reduction in the use of conventional fuels and/or raw materials through substitution. This phenomenon, the use of wastes as raw material or as a source of energy or both, is familiar as Co-processing. Mainly employed in energy intensive industries (EII) such as cement, lime, steel, glass, paper and power generation (wikipedia¹), co-processing is treated as material recycling and energy recovery efforts by replacing the use of natural mineral resources and fossil fuels respectively in industrial processes. Under ideal conditions, good combustion destroys most of the non-metallic, toxic organic compounds in hazardous waste and leaves ash residues which are easier to dispose of than raw, untreated wastes. Co-processing is a popular term of industrial ecology (IE) – a new dimension of the modern business sustainability.In particular, the co-processing of waste in kilns, the subject of appropriate guidelines, allows the recovery of the energy and/or mineral value from waste, while the intended products are being manufactured.

The Basel Convention [2] places obligations on countries that are Parties to ensure the environmentally sound management (ESM) of hazardous  and other wastes. In this regard, the guiding principle, broadly accepted for securing a more sustainable waste management system, is the waste hierarchy of management practices (with due consideration given to the protection of the environment and human health). The hierarchy places waste prevention (avoidance) and operations that may lead to resource recovery, recycling reclamation, direct re-use or alternative uses, in a pre-eminent position relative to operations which do not lead to such possibility. Thus, where waste avoidance is not possible, reuse, recycling and recovery becomes a preferable alternative to non-recovery operations. To this end, co-processing in kilns provides an environmentally sound resource recovery option for the management of hazardous and other wastes, preferable to land-filling and incineration.

Alternative Fuel (AF) and Alternative Raw Material (ARM)

Waste materials used for co-processing are referred to as alternative fuels (AF) and alternative raw materials (ARM). Alternative fuels and raw materials are predominantly wastes or by-products from agricultural, domestic, forestry or industrial processes comprising biomass (e.g., rice husk), animal meal, sewage sludge, municipal solid wastes, used tyres, spent solvents, waste oils, etc.

A wide range of hazardous waste materials can be co-processed, such as ETP sludge, paint thinners, paint sludge, refinery sludge, used oil, solvents or end-of-line products from the transport sector, etc. Solids and liquids from the cleanup of past uncontrolled hazardous waste dump sites can also be blended as AF and ARM into hazardous waste streams.

fields (as is the case with agricultural organic waste), methane gas is produced (Kabir and Halim, 2011, ChE Thoughts 2(1), pp 16). Methane, a powerful Greenhouse Gas, is 21 times more potential (Global Warming Potential) than CO₂.Replacing traditional fossil fuels with AF will reduce overall greenhouse gas (GHG). Three global problems: a) unsustainable waste management practices, b) the increasing scarcity of fossil fuels, and c) climate change, are the main drivers behind the growing substitution of so-called alternative fuels (AF) for conventional fuels. Replacing traditional fossil fuels with AF reduces overall CO₂ emissions because, in their traditional disposal methods, many of the AF used will otherwise generate CO₂emissions with no energy recovery. Therefore, emissions generated by the combustion of AF with biomass contents are considered “carbon neutral”. In fact, during the natural decomposition process that occurs when waste is landfilled or left in the fields (as is the case with agricultural organic waste), methane gas is produced (Kabir and Halim, 2011, ChE Thoughts 2(1), pp 16). Methane, a powerful Greenhouse Gas, is 21 times more potential (Global Warming Potential) than CO₂.

Hazardous wastes not recommended for co-process

Not every kind of waste can be used for co-processing, keeping in view the environment, health, safety and operational concerns. The wastes listed below are normally not recommended for co-processing till otherwise proved/evidenced for.

• Biomedical waste
• Asbestos containing waste.
• Electronic scrap.
• Entire batteries.
• Explosives.
• Corrosives.
• Mineral acid wastes.
• Radioactive Wastes.
• Unsorted municipal garbage.

Benefits of Alternative Fuels (AF)

The benefits of substituting alternative fuels (AF) for conventional fuels include:

• Resource saving: By recovering energy from wastes, AF save conventional non-renewable fossil fuels, contributing to the sustainability of our world.

• Waste management: AF offer local communities and governments a neat, final, and environmentally friendly solution to dispose of wastes, effectively avoiding the use and hygienic challenges of landfills. Rapid urbanization with significant increase in municipal solid waste coupled with stringent environmental regulations to reduce landfill disposals are generating worldwide interest in the recovery of energy from Municipal Solid Wastes (MSW).

• Local economic development: In many cases, the economic activity related to the development of the AF supply chain fosters local value creation and employment.

• Climate change mitigation: AF, particularly biomass fuels and the biomass fraction of household wastes, help reduce the CO₂ footprint and eliminate emission of this most significant greenhouse gas.

• Potential local environmental benefits: Many AF have also been shown to reduce other kiln emissions—particularly nitrogen oxide (NOx)—thereby enhancing local air quality.

Global Practice especially in Cement Kiln– Utilization and Volume of AF

Fossil fuels and raw materials have been successfully substituted by different types of wastes in cement kilns in Europe, Japan, United States, Canada and Australia since the beginning of the 1970s (GTZ/Holcim, 2006).The countries with the largest quantities co-incinerated in cement industry alone were France and Germany (>800,000 tpa) followed by Belgium and Austria (> 100,000 tpa). [3]

Technical requirements and Operating conditions for co-processing in Cement Manufacturing:

Although the practice varies among individual plants, cement manufacture can consume significant quantities of wastes as fuel and non-fuel raw materials. This consumption reflects the process characteristics in clinker kilns, which ensure the complete breakdown of the raw materials into their component oxides and the recombination of the oxides into the clinker minerals. The essential process characteristics for the use of hazardous and other wastes, fed to the kiln via appropriate feed points, may be summarised as follows (European IPPC Bureau, 2009) [2]:

–        Maximum temperatures of approximately 2000°C (main firing system, flame temperature) in rotary kilns;

–        Gas retention times of about 8 seconds at temperatures above 1200°C in rotary kilns;

–        Material temperatures of about 1450°C in the sintering zone of rotary kilns;

–        Oxidising gas atmosphere in rotary kilns;

–        Gas retention time in the secondary firing system of more than 2 seconds at temperatures above 850°C; in the precalciner, the                           retention times are correspondingly longer and temperatures are higher;

–        Solids temperatures of 850°C in the secondary firing system and/or the calciner;

–       Uniform burnout conditions for load fluctuations due to the high temperatures at sufficiently long retention times;

–        Destruction of organic pollutants due to the high temperatures at sufficiently long retention times;

–        Sorption of gaseous components like HF, HCl, and SO₂ on alkaline reactants;

–        High retention capacity for particle-bound heavy metals;

–        Short retention times of exhaust gases in the temperature range known to lead to formation of polychlorinated dibenzo-p-dioxins               and polychlorinated dibenzofurans (PCDDs/PCDFs);

–        Complete utilisation of fuel ashes as clinker components and hence, simultaneous material recycling and energy recovery;

–        Product specific wastes are not generated due to a complete material utilisation into the clinker matrix (although some cement plants dispose of CKD or bypass dust);

–        Chemical-mineralogical incorporation of non-volatile heavy metals into the clinker matrix.

Limiting Factors

Although using alternative fuels is desirable, occasionally they cannot be used due to processing issues, lack of permits or poor availability. While traditional fuels have the disadvantage of high cost, they are generally more uniform and more capable of providing a consistent heat profile. The cost benefits and environmental advantages associated with alternative fuels make them highly desirable for many companies. However, because of factors like limited availability, high entry costs, potential process issues and quality concerns, AF may not be a suitable choice for every plant. Though the cost savings associated with alternative fuels may be significant, there are usually a number of drawbacks that can adversely affect output and product quality to varying degrees. For example, most alternative fuels are usually associated with excess air and high moisture. Co-processing plants should be designed, equipped, built and operated to prevent air pollution, especially at ground level, due to emission. Ambient air quality should be maintained while discharging exhaust gases, so as to safeguard human health and the environment. Above all, the management of the co- processing plant should be in the hands of a skilled person, competent enough to manage the hazardous wastes in an environmentally sound manner.

Email: k.ahmmed@mail.mcgill.ca

Expecting something out of the ordinary, I attended the last lecture delivered by Dr. A.K.M.A. Quader. My expectation fulfilled, I was mesmerized and I enjoyed every bit of the lecture! Public lectures titled, “Last Lecture”, are practiced in many renowned international universities. Usually comprising of subject matters well outside the academic’s research area, the lecture is delivered to the public as if it was the last.

The tradition of last lectures is very recent in Bangladeshi universities. Bangladesh University of Engineering and Technology (BUET) is initiating to organize such opportunity for senior teachers and Dr. Quader’s one is the first to deliver one as such. So, when he was suggested to deliver a lecture commemorating his retirement, it created hype among his peers, current and ex-students. The Last Lecture of Dr. Quader’s was attended by a large number of audiences. On June 18th, 2011 the Council Building of BUET was crowded with faculty members and colleagues from different departments including his own, the Department of Chemical Engineering, students, engineering professionals and peers from the civil society.

Dr. A.K.M.A. Quader

Dr. Quader retired from the Department of Chemical Engineering, BUET on June 30, 2011. He joined the department as an Assistant Professor in 1973, and since then he has devoted himself as an academic and in many occasions as a professional chemical engineer.

Dr. Quader’s last lecture was divided into several sections. It was as if he was narrating his autobiography in front of the audience. It was interesting how Dr. Quader presented his life with an engineering perspective in his lecture. He represented his lifelong achievements and experiences on a log-log plot. He emphasized on his childhood and discussed his ambitions and goals. He shared his emotions and also the bittersweet memories with the audience.

Of the many things that Dr. Quader shared with the people at the lecture, it was interesting to learn that teaching was never an agenda in his early life. Rather, he aspired to be an engineer. After graduation, Dr. Quader joined the then Council of Scientific and Industrial Research (now Bangladesh Council of Scientific and Industrial Research (BCSIR)). After completing his PhD from University of Bradford, UK he rejoined the BCSIR in 1972, in spite of receiving an offer at the University of Bradford as lecturer. After working at BCSIR for a year, he resigned and joined the Department of Chemical Engineering, BUET. What changed his mind to join the department was unanswered in his lecture. And, though he enjoyed what he did, he still thinks that it was a wrong decision in Today’s context of Bangladesh.

It was an exciting start of Dr. Quader’s career at BCSIR, where he could not only apply his own talent but also the knowledge he gained thus far, which he always wanted. There, he worked on process development at the pilot plant scale. His PhD work was also on experimental research. For his PhD project, he built a big and complicated experimental rig which was a good learning experience for him. To gain real life engineering experiences, he often visited industries and establishments. He believed that to be a successful engineer, it is important to use one’s common sense along with the underlying principles of science and engineering.

As a BUET faculty he always assigned experimental works including designing, building and operating engineering projects to his supervisees. In his last lecture he acknowledged his students and mentioned that when it came to learning, he learned a lot from them while teaching in the classes and supervising design and thesis projects.

In my years of working with Dr. Quader as a student and later as a junior colleague I got a notion that his engineering contributions in the process industries in Bangladesh are highly appreciated. And by listening to his lecture, my notion was reconfirmed. He participated in a number of trouble-shooting events, consultancies and managerial tasks in different chemical and allied industries. One of his decision making events was with Toyo Engineering Corporation, which was the General Contractor for building a large capacity fertilizer industry in Bangladesh. His decision of changing Toyo’s proposed design saved a significant amount of foreign currency of the country and also ensured safety of the plant.

In his lecture, Dr. Quader brought up a number of thought evoking issues. He marked the challenges of chemical engineering in Bangladesh and made comments and suggestions to overcome those. He expressed his satisfaction with the young graduates, who he believes are full of new ideas and have the ability to learn from their failures.

Dr. Quader, who has achieved many successes throughout his career, is sure to have many proud moments, and in his ‘Last Lecture’, he shared them with the audience. According to him, the independence of Bangladesh is the best moment of his life. He actively participated in different organizations of Bangladesh Liberation Movement while staying in UK. At one point his scholarship was terminated by the request of the then Pakistani government for his participation in these organizations. But, the scholarship was reinstated by his active communications with British MPs.

Dr. Quader concluded his lecture with votes of thanks and acknowledgments. He remembered his parents and his family’s contribution towards his success. He thanked his mentors and friends. Finally, he thanked all of those who had worked with him- colleagues, students and staff members.

As an academician and an engineer, Dr. Quader has oared the concept of chemical engineering design for decades. He always tells students: “Fight to finish, never give up or give in”. Undoubtedly, Dr. Quader is a true fighter, who has inspired hundreds of his followers and well-wishers. Dr. A.K.M.A Quader, you will be greatly missed!

Moments from Dr. Quader’s ‘Last Lecture’.

Department of Electrical and Computer Engineering, McGill University, Montreal, Canada

Email Addresses: md.nazir@mail.mcgill.ca

Research Notes: Received 04 November 2011; received in revised form 28 February 2012; online published 16 July 2012

Abstract

Large scale integration of distributed generation (DG) sources require significant restructuring in operations and planning of electric power. While a more decentralized architecture is envisioned, operators may need to overcome several technical and economic challenges to adapt to such paradigm shift. This paper highlights some of those key challenges and discusses the importance of efficient forecasting and agent based modeling in managing DGs in a decentralized architecture.

Keywords – Distributed generation, renewable, decentralized, agent-based control, forecasting

I. Introduction

The electricity industry is going through a massive restructuring years with significant interest and technological advancements in distributed generation (DG) sources, such as small to medium scale solar photovoltaic, wind, micro-hydro, fuel cells, etc. The innovations in these technologies and industry adoption are mainly driven by environmental concerns [1, 2]. However, in an electricity system that up to now has been very centralized, the economic as well as technical challenge will be to optimally integrate the increasing number of decentralized small generation units. By understanding and properly addressing the technical and economic challenges, it will be possible for the system operators to ensure optimal planning for expansion of generation, transmission and distribution facilities, ensure secure reliable supply of electricity while securing the interest of the end user.

Due to fast growth in ‘active’ distribution networks, power systems need to adjust operating under decentralized control architecture rather than centralized control architecture [1]. In this paper, the possible roles of intelligent forecasting tools and agent-based control are highlighted to manage the future power systems.

II. Characteristics of DG Sources

Chambers [3] defines DGs as relatively small generation units of 30MW or less, while Ackermann et al. [4] define DGs in terms of connection and location rather than in terms of generation capacities. They define DG sources as electric power generation units connected directly to the distribution network or on the customer sides of the meters. Residential or industrial customers, distribution network operators or even traditional power generation companies can own DG units. Table 1 lists the different DG technologies and indicates their respective characteristics.

 Table I: Characteristics of distributed generation sources [1].

Many DG sources use cheap fuel (or ‘free’ in case of wind and solar) and some can act in co-generation mode (cogeneration of heat and electricity). Depending on the type of fuel used and its impact on the environment, many of the DG sources (wind, solar, hydro, biomass-fuelled plants, etc.) are considered as renewable sources. The growth of such distributed sources can ensure larger portion of renewable energy in the overall generation mix. However, sources such as wind and solar are highly weather driven and thus the control is more challenging.

 III. Benefits and Issues Related to Distributed Generation

A. Benefits

Environmentally friendly and lower emission of carbon-dioxide and other toxic gases, these are the main factors driving the growth of renewable distributed sources. Regulatory bodies and policymakers of many countries have put favorable policies in place to promote the growth of such clean energy. Secondly, since many DG sources (except wind farms) can be located close to the loads, thus transmission losses are greatly minimized and the need for investing in expensive transmission lines is reduced. According to International Energy Agency (IEA) [5], on-site production could lead to cost savings in transmission and distribution of about 30% of electricity cost. Thirdly, IEA [5] recognizes the importance of DG in providing reliability services for the power systems. Moreover, in countries that operate under deregulated electricity markets, DG sources can serve as a hedge against price fluctuations since customers also have a flexible mechanism to respond to market conditions rather than simply being the ‘price taker’.

B. Issues

Besides the typical high financial cost during initial installment, there are additional challenges that hinder the rapid integration of renewable DG. Since power systems traditionally operate in centralized mode, the new shift to distributed sources leads to some complications. There have been major concerns related to uncertainty in forecasting weather-driven natural sources such as wind and solar. For example, wind power outputs are highly variable and often experience large positive or negative ramps, i.e. output fluctuations [6]. Forecasting these ramps and allocating back up resources to cover such ramp events in an economic and reliable manner is a challenging task. In the case of high wind velocity, the wind farms need to curtail wind, i.e. spill wind by changing turbine blade angles, since the system operators may not be able to fully compensate for rapid ramp ups or downs of wind due to technical or economic reasons. However, since it is intuitive not to waste such ‘free’ energy, development of highly efficient forecasting tools are enforced. Similarly, solar outputs can fluctuate sharply and hence proper forecasting tools for optimal storage sizing is essential.

Moreover, large scale deployment of decentralized sources of electricity may lead to instability of the voltage profiles since bidirectional power flows and complicated reactive power flows may arise [1]. When connecting DG to grid, operators need to ensure voltage stability and reliability which requires careful and detailed studies.

IV. Overcoming Challenges

A. Forecasting Tools

Since the weather driven renewable sources of electricity introduce uncertainty in the model, these uncertainties must be characterized efficiently and the controllable part of the generation sources must be flexible enough to mitigate the risk associated with uncertainty and variability of the renewable sources [7]. Advanced probabilistic forecasting tools can contribute greatly by efficiently modeling the characteristics of such renewable sources. Large collection of data from various sources (meteorological sites, wind firms, solar plants etc) with high degree of resolution (minutes/ seconds) is required to build efficient forecasting tools.

Moreover, machine learning algorithms and Kalman filtering techniques can be very useful in learning the dynamic characteristics of variable sources and predicting the future states of the network. System operators can benefit from such tools in predicting the level of backup resources that need to be allocated to ensure power systems can operate reliably even during large ramp events in weather-driven sources.

B. Decentralized Agent-based Control

In a decentralized architecture, the role of communication systems and automation is crucial. From customer household/industrial appliances to DG sources including the traditional large power plants, everything can be thought of as agents. Efficient coordination among all these agents is the key to ensure a functional and reliable power system.

Distributed artificial intelligence concepts can be implemented to model an efficient agent-based system [8]. In the agent-based systems, various layers of information, such as the technical conditions (voltage levels in the local network, frequency, outage information etc) and the market conditions (price, spikes, etc.), need to be monitored and communicated with other agents so that agents can negotiate and coordinate. Control algorithms dictate the actions of the agents while respecting all the technical constraints of individual agents and of the network.

Agent-based models are already being used in applications in the area of electric wholesale markets, health care, transportation, etc [9]. These frameworks can be extended to model agent-based operations of power systems. The utility service area can be represented by a sample of utility customers. In the agent-based model, the customers are characterized by end-use equipment holdings, end-use electricity use and hourly loads, demographic and other variables [10], while the generating units can be characterized by their size, operations, flexibility, generation patterns etc.

In a highly flexible market platform, the actions of agents should be supported by economic justifications. The agents representing power suppliers and customers act as self interest maximizing entities, while an operator agent can act to make sure the technical constraints and the local policies are always met during negotiations. Efficient coordination among the agents is realized through a market mechanism that incentivizes the agents to reveal their policies truthfully to the market [11], thus establishing a functional agent-based reliable power system. The dynamic behavior of the agents and the overall system can be better characterized over time with availability of data.

V. Conclusions

With the trend leading towards renewable, decentralized, and highly fluctuating distributed generation sources, there is a tremendous challenge regarding the stability of future power grids. Hence, agent-based decentralized control and advanced forecasting tools can add great value in realizing large scale integration of distributed resources in electric power systems.

VI. Acknowledgements

The author likes to acknowledge Professor François Bouffard, Dept. of Electrical and Computer Engineering, McGill University.

VII. References

1. G. Pepermans et al., 2005, Distributed generation: definition, benefits and issues/ Energy Policy, 33, 787–798.
2. Renewables Global Status Report: 2009 Update. Renewable Energy Policy Network for the 21st Century (REN21), Paris, 2009.
3. Chambers, A., 2001. Distributed generation: a non-technical guide. PennWell, Tulsa, OK, p. 283.
4. Ackermann, T., Andersson, G., Soder, L., 2001. Distributed generation: a definition. Electric Power Systems Research 57, 195–204.
5. IEA, 2002. Distributed Generation in Liberalised Electricity Markets, Paris, p. 128.
6. Erik Ela and J. Kemper, 2009. Wind Plant Ramping Behavior. National Renewable Energy Laboratory, USA.
7. F. Bouffard and M. Ortega-Vazquez, 2011. The value of operational flexibility in power systems with significant wind power generation. IEEE Power and Energy Society General Meeting.
8. T. Sandholm. Distributed rational decision making. In G. Weiss, editor, Multiagent Systems: A Modern Approach to Distributed Artificial Intelligence. MIT Press, 2000.
9. Tesfatsion, L.S., Judd, K.L., 2006. Handbook of computational economics. Agent- Based Computational Economics, 2. Elsevier/North-Holland (Handbooks in Economics Series).
10. J. Jackson, “Improving energy efficiency and smart grid program analysis with agent-based end-use forecasting models,” Energy Policy, vol. 38, no. 7, pp. 3771–3780, 2010.
11. S. Lamparter, S. Becher, and J.-G. Fischer, “An agent-based market platform for Smart Grids,” in Proceedings of the 9th International Conference on Autonomous Agents and Multiagent Systems: Industry track, Richland, SC, 2010, pp. 1689–1696.

Dr. Mannan has been teaching for over 33 years, and mentoring the next generation in the quest for new knowledge has always remained his interest. In this context he shared, “Every moment of a student’s experience in the university should involve some kind of learning.” Dr. Mannan also thinks that there is a lack of integration between today’s engineering education and modern industrial practice. Engineering students must understand the social and global role of engineers and they must be able to accept and face the challenges, he added.

Apart from teaching, Dr. M. Sam Mannan is also serving as the director at Mary Kay O’Connor Process Safety Center. An internationally renowned expert on process safety and risk assessment, Dr. Mannan is a member of AIChE, American Society of Safety Engineers, the International Institute of Ammonia Refrigeration and the National Fire Protection Association (NFPA). He is also a co-author of the book “Guidelines for Safe Process Operations and Maintenance.” His research interests include abnormal situation management, aerosol research, inherently safer design, quantitative risk assessment, reactive chemicals, modeling of silane releases,LNGsafety and design and flammability research. He has served as a consultant to numerous entities in both academic and private sectors. He believes that engineers have both professional and global responsibilities to design materials, processes, products and systems to sustain safe and sound conditions for human health and environment.

In his speech at the Convocation Ceremony of University of Lodz, Dr. Manna mentioned the honor of receiving the award as one of the most significant and highest honors conferred upon him. He also added that during the influential period of his undergraduate education, Professor Dr. Iqbal Mahmud, Bangladesh University of Engineering and Technology (BUET) left an indelible impression on him, which propelled him forward in his lifelong quest.

Email: faujia_j27@hotmail.com

There was an air of eagerness, anxiousness and surely competitiveness on the morning of ‘ICChE 2011 Poster Competition’, held on 30^th December, 2011 at the Department of Chemical Engineering, BUET. One of the key attractions of 3^rd International Conference on Chemical Engineering (ICChE) 2011, this year’s student poster competition had 25 participating teams of 88 undergraduate students from different engineering departments. Jointly organized by the ChemicalBUET, BUET Chemical Engineering Forum (BCEF) and the Department of Chemical Engineering (ChE), BUET, the poster competition is a sheer reflection of the enthusiasm and interest of students in participating in multidimensional competitions. Participating teams were divided into two groups: Group A comprising of students of Levels 1 and 2, and Group B comprising of students of Levels 3 and 4. At the competition, participants exhibited and presented scientific, technical and engineering posters to the audience and the judges. Group A teams presented their posters on the cutting edge technologies of today, while Group B teams mostly exhibited posters on their thesis projects.  The panel of judges included academicians and researchers from international institutes including Texas A&M University (USA), Indian Institute of Technology (IIT, Kanpur, India), and University of Alberta (Canada). Teams were judged based on features including overall appearance and content of the posters, and the oral presentations made to the audience. There were in total six winning teams, three from each group. The names of the winning teams were announced at the end of the contest and all participants were given certificates of participation. The winning teams were awarded at the Closing Ceremony of the 3^rd International Conference on Chemical Engineering (ICChE) 2011. Dr. A.K.M.A Quader, Professor, Dept. of ChE and Chairman, ICChE 2011 gave away awards and certificates to the winners. Member of the organizing committee Munir Ahammad, Lecturer, ChE BUET and student volunteers Asif Hasan Rony and Md. Rifat Mahmud contributed in coordinating the competition. Dr. Mohidus Samad Khan (McGill University), Convener, ICChE Poster Competition 2011, was the moderator of the competition and award giving ceremony. With the joy of the elated winners and the appreciation from the conference attendees, the poster competition came to a fruitful end.

Moments from ICChE 2011 Poster Competition and Award Ceremony.

Of enthusiastic participants, a burning presentation session and a splendid award ceremony– the Chemical Engineering (ChE) Undergraduate Thesis Competition 2011 kicked off on 10^th December, 2011. Aimed to create the opportunity to exhibit their research works to a wide spectrum of audience, the competition surely builds a sense of challenge and an instinct for research in the participants. Jointly organized by the Department of Chemical Engineering (ChE), BUET, BUET Chemical Engineering Forum (BCEF) and ChemicalBUET, this year’s competition was marked by fresh project ideas and a tight contest.

Dressed in formal attires and adorned with a confident attitude, the graduate participants gathered at the Dept. of ChE on the morning of 10^th December, 2011. The program began with the inauguration speech by Dr. Dil Afroza Begum, Head, Dept. of ChE, BUET. With the participants presenting their undergraduate thesis projects, judges keenly observing the presentations, and a little refreshment for the audience to enjoy, the overall ambience of the competition was that of nervousness and of spirit. Participants were judged on two major attributes, their thesis works and the multimedia presentations. Prior to the competition, graduates submitted an extended abstract of their research projects along with their theses that were judged by a group of academicians and industrial personnel. During the presentation, participants were judged on how well they presented their work to the open audience and the like. The judges raised questions on the scientific and financial feasibility of their projects, and placed challenging scenarios in front of the participants. The judges of this year’s competition were Dr. Iqbal Mahmud, Professor Emeritus, ChE and Ex-VC, BUET, Dr. Nooruddin Ahmed, UGC Professor and Ex-VC, BUET, Dr. Khaliqur Rahman (presentation) and Eng. Md. Mohiuddin (thesis review). Dr. Mohidus Samad Khan (McGill University), Convener, ChE Thesis Competition 2011, was the moderator of the presentation session, while Munir Ahammad, Lecturer, Department of Chemical Engineering, BUET and a member of the organizing committee, contributed in coordinating the event.

The presentations made and the judges’ marks finally summed, the competition came to an end with the announcement of the winners. The third position ranker was Fauzia Sultana for the thesis on `Production of Calcium Chloride by Limestone-Hydrochloric Acid Process´, supervised by Dr. A K M A Quader.  The second position went to two teams, Aurko Ali andEmon Hasan for `Assessment of Environmental Pollution from Pharmaceutical Industries in Bangladesh´, supervised by Md. Mominur Rahman and Bayzid Kabir, and Lubna Ahmed and Farzana Quddus for `Modeling of Air Pollution in Dhaka City from Northern Brick Kilns Using AERMOD´ supervised by Dr. M A A Shoukat Choudhury. The first place winner of this year’s competition was Sujala Tajneen Sultana for the project on `Design and Performance Evaluation of an Improved Multi-pot Biomass Cooking Stove’, supervised by Md. Mominur Rahman. All participants were handed certificates of participation by Dr. Dil Afroza Begum.

The achievement of the winners of ChE Undergraduate Thesis Competition 2011 was acknowledged by awarding crests and certificates at the 3^rd International Conference on Chemical Engineering (ICChE) 2011 on 30^th December, 2011. Supervisors of the winning teams were also awarded certificates of appreciation. With the awardees posing for photographs and later attending the formal dinner of ICChE 2011, the ChE Undergraduate Thesis Competition 2011 came to a successful end.

Moments from the ChE Undergraduate Thesis Competition and Award Ceremony 2011.

Department of Electrical and Computer Engineering, McGill University. Montreal, Quebec, Canada.

Email Address: kibria.ca@gmail.com

Research Highlights: Received 12 December 2011; received in revised form 24 June 2012; online published 16 July 2012

1. Global Energy Crisis

Our planet is heading towards an energy famine. According to the U.S. Department of Energy, the worldwide primary energy consumption in 2008 was ~17 terrawatts (TW, one TW equals 10¹² watts, or 10¹² joules per second), which is expected to  double by 2050 and triple by 2100 [1]. Needless to say, this is because of the growing world population, which was 6.2 billion in 2006, 7.0 billion  in 2011 and  is projected to be 9.4 billion by 2050 [2]. Therefore, by 2050, an additional 17 TW energy supply is required for the extra 2.4 billion people, considering the current living standard of world population and with the best conservation of energy. Considering Bangladesh as an example, only 50% of Bangladeshis have access to electricity at present with a per capita generation of ~252 KWH [3]. According to the Power Sector Master Plan 2010 [3], the power demand in 2030 will be nearly 34,000 MW. With the current generation of around 5,200 MW [4], Bangladesh will require an additional ~29,000 MW power in 2030. Therefore, it is imperative to explore alternate sources of energy to cope up with this energy crisis.

2. Alternative Energy Sources

There are different types of energy sources currently available; however, not all of them can follow our current and future energy demand curve. For example, biomass offers a limited energy supply because of the low efficiency of photosynthesis [5]. Alternatively, nuclear energy plant is assumed to be a solution to this energy crisis. However, the deployment of expensive nuclear plant is difficult to build fast enough to cope up with the energy demand. Also nuclear power plant requires widespread public acceptance, since they can be a point of catastrophic disaster as seen by the world recently in Fukushima, Japan [6]. Wind energy is a poor choice because of its low energy density and intermittency [7].  While the fossil energy resources (i.e., gas, oil, coal, etc.) can satiate the global energy appetite, the atmospheric CO₂ released from burning this fossil fuel significantly increases greenhouse gas (GHG), which can perturb the ecosystem of the planet. Therefore, it is vital to find alternative carbon-neutral energy sources that can mitigate the current and future global energy appetite.

3. Solar Energy

Solar energy is the ultimate solution offering carbon-free energy. About 1.2× 10⁵ TW power from sunlight falls on the Earth’s surface in 1 hr, which is higher than the global energy consumed by all human activities in 1 year [8]. Approximately 600 TW power from sunlight strikes the Earth’s terrestrial surfaces that can be used as practical sites for solar energy harvesting [9]. Covering 0.16% of the land on Earth with 10% efficient solar conversion systems would provide 20 TW of solar power, which is nearly twice the world’s fossil fuel consumption rate [10]. Clearly, solar energy is the largest renewable carbon-free resource amongst all other renewable energy options. However, the major challenges in implementing large scale solar energy system are the low efficiency and the high manufacturing cost of solar panels. Furthermore, for penetrating the global energy market, new technologies need to be developed to store solar energy, which can be released in a form that one desires, whether it is electrical, chemical or mechanical.

4. Importance of Solar Energy Storage

Because of the diurnal nature and intermittency arising from variable atmospheric conditions, it is imperative to find a solution to store and supply solar energy for 24 hours a day, 7 days a week. Solar energy storage offers the following significant advantages: (1) an efficient storage mechanism allows synchronization between solar power supply and demand curves, (2) a cost effective solar storage system will offer highly distributed off-grid power supply system, (3) because of its highly distributed and decentralized nature, solar energy storage offers geopolitical stability [11]. Therefore, it is vital to innovate and design new materials and techniques to store solar energy in cost effective ways.

5. Current Techniques for Solar Energy Storage

The current methods of storing solar energy are too expensive and inefficient for large scale applications. There are mainly four forms of energy storage technologies [11]: (1) potential energy (pumped-hydroelectric, compressed-air, electric charge in super/ultra capacitors), (2) kinetic energy (flywheels), (3) thermal energy (concentrated solar thermal, geothermal), and (4) chemical energy (in the form of batteries or fuels). The energy storage system based on potential energy, kinetic energy and thermal energy experiences high cost of deployment, short time storage, and low energy density to be implemented for large scale applications. The electrochemical energy storage in the form of batteries or capacitors is only limited to small scale and short term applications because of their low energy density and short life time.

On the other hand, energy storage in the form of chemical fuels, such as hydrogen (H₂) gas or hydrocarbons offers sustainable energy for small/large scale, and short/long term applications.  Although H₂ has the highest energy density by mass (143 MJ Kg), it suffers from low volumetric energy densities [11]. On the other hand, hydrocarbon fuels offer the optimum volumetric energy density, and therefore can be used as a renewable energy carrier for modern society.

6. Necessity for Solar Water Splitting

At present, hydrogen is mainly produced from fossil fuels and therefore the production process emits CO₂. However, H₂ needs to be produced from abundant natural resources, such as water and sunlight. Splitting water into H₂ and O₂ using sunlight allows storing solar energy in the form of chemical energy and makes solar energy 24 hours a day, 7 days a week. This process produces hydrogen: a clean, storable and renewable source of energy. The released H₂ from water splitting can be used in fuel-cells to produce electricity or can be directly combusted in an engine, wherein the reaction byproduct is nothing but water. This process will make solar energy highly distributed, from small to large scale applications. Therefore, research on solar water splitting is an urgent need. However, the current technologies for solar water splitting in a cost effective and efficient way are still at their infancy.

7. Solar Water Splitting

Splitting water into hydrogen and oxygen with sunlight is one of the ‘holy grails’ of chemistry. Since the pioneering work by Fujishima and Honda [12], considerable researches have been focused over the last 40 years on developing a stable and efficient photocatalyst material for solar water splitting [13], with limited success. A photocatalyst material is required to absorb solar photons and subsequently use the photon energy to break the chemical bonds of water. A photocatalyst material needs to satisfy three requirements to be able to split water: (i) the band gap has to be higher than 1.23 eV (as discussed later), (ii) suitable band-edge potentials with respect to water oxidation and reduction potential (as discussed later), and (iii)  stable against photocorrosion [13]. Although a number of metal oxides satisfy all of the above mentioned requirements, they are not, however, suitable for practical applications. This is because metal oxides usually possess a large bandgap (> 3 eV), and hence can harvest only the UV portion of solar spectrum. Since, only ~4% of solar spectrum lies in the UV region, the solar to hydrogen conversion efficiency of the metal oxides remains impractical. Therefore, tremendous effort has been made in the last decade to harvest visible photons, as visible light accounts for ~46% of solar irradiation [14].

There are mainly two approaches for water splitting: photocatalytic and photoelectrochemical (PEC) water splitting. In photoelectrochemical water splitting, the photogenerated carriers (electron or holes) in the semiconductor photocatalyst (i.e., TiO₂) are channeled through a metallic conductor to an electrode, which is modified by catalysts (Pt) (Fig. 1 A). In this case, some external bias is usually required for efficient carrier separation and to overcome the resistance between the electrodes in the solution. In photocatalytic water splitting, the catalysts (Pt, in this case) are integrated onto the semiconductor (TiO₂) and the photogenerated carriers are directly captured by the catalyst (Fig. 1 B) [15].

Figure 1: (A) Photoelectrochemical water splitting on TiO₂ photoanode, (B) Photocatalytic water splitting on TiO₂ particle [15].

In both approaches the water splitting reaction converts solar energy into chemical energy with a positive change in Gibbs free energy (i.e., uphill reaction) [15].

H₂O → O₂ + H₂,                        ΔG=+237.178 KJ/mol

Therefore, water splitting reaction can store 237.178 KJ/mol at 25 °C and 1 bar. This reaction is regarded as artificial photosynthesis, as it resembles the natural process of photosynthesis by which green plants store solar energy.

8. Main Processes Involved in Solar Water Splitting

The water splitting reaction generally involves three main processes [13, 15] as shown in Figure 2 [16]. (1) The first step is band gap absorption of photons and generation of electron–hole pairs. Thermodynamically, when the energy of incident light is larger than the band gap energy, electrons and holes are generated in the conduction and valence bands, respectively. (2) The second step consists of charge separation and migration of photogenerated carriers. The physical size of the photocatalyst determines the activity of the photocatalyst. If the size is small, the photogenerated carriers will have to travel a small distance to reach the surface and hence there will be less probability of carrier recombination. Therefore, development of high quality nanoscale material is of great interest.

Figure 2: (Three main processes involved in photocatalytic water splitting. Here, the host nanowire photocatalyst is used to capture solar photons. The nanowire is decorated with some metal nanoparticles as H₂/O₂ evolution catalyst to enhance the redox reaction [16].

(3) The final step involves the reduction and oxidation (redox) of water on the photocatalyst surface via the photogenerated electrons and holes, respectively. It is a common practice to incorporate some H₂ and O₂ evolution catalyst on the host photocatalyst (nanowire in this case) to enhance the extraction of electrons/holes and reduce the activation energy barrier for gas evolution, as shown in Figure 2.

For water splitting, first, the O-H bonds of two water molecules need to be broken with the simultaneous formation of one O=O double bond as follows [11].

H₂O ↔ O₂ +4e^- + 4H⁺,      E_anodic=1.23 V – 0.059 (pH) V (NHE)             …………….(1)

Since this reaction requires a high oxidizing potential, 1.23 V vs. NHE (normal hydrogen electrode) (pH=0), the top level of valence band has to be more positive than this potential, so that the photogenerated holes have enough energy to oxidize water. This reaction releases four protons (H⁺) and four electrons (e^?), which need to be combined to form two H₂ molecules, as follows [11]:

             4H⁺ + 4e^-  ↔ 2H₂,   E_cathodic = 0 V – 0.059 (pH) V (NHE)                             ………….(2)

Therefore, the conduction band of the semiconductor has to be more negative than water reduction potential (0 V vs. NHE (pH=0)). Thus, water molecules are oxidized by the holes to form O₂ and reduced by the electrons to form H₂ for overall water splitting. Therefore, the theoretical minimum band gap for water splitting is 1.23 eV that corresponds to light wavelength of about 1000 nm. A photocatalytic water splitting reaction over a semiconductor material is schematically shown in Figure 3 [13].

Figure 3: Schematic diagram of band edge requirements for water splitting reaction [13].

For practical applications, water splitting has to be achieved under visible light (> 400 nm) using an Earth abundant, stable and efficient photocatalyst material. Researches on visible light responsive photocatalyst are limited as there are very few stable materials that satisfy the thermodynamic and kinetic potential for overall water splitting under visible light [17-18]. Therefore, different band engineering methods have been developed to transform ultraviolet (UV) light (<400 nm) active materials into visible-light active photocatalysts [19-21]. While band engineering improves the visible light activity of these photocatalyst materials to some extent, there are still very few reliable and efficient photocatalyst for overall water splitting under visible light. Therefore, it is vital to explore new visible light responsive photocatalysts that are stable and efficient for overall water splitting.

On the other hand, recent advances in nanotechnology possess immense potential for efficient harvesting of solar energy. For example, one dimensional (1D) nanostructures, such as nanowire, nanotubes or nanobelts can be made using two approaches, namely top-down and bottom-up. Because of their high crystallinity and surface-to-volume ratio, these 1D nanostructures are capable of efficient light absorption and carrier separation [22]. Hence, a boost in solar to hydrogen conversion efficiency is expected. Figure 4 shows a schematic of large scale H₂ production system via solar water splitting, as depicted by Domen et al. [23]. According to their calculations, about 10,000 solar water splitting power plant (25 km² each) would be required to supply one-third of the projected energy needs of human society in 2050.

Figure 4: Large scale H­₂ production via solar water splitting [23].

Although H₂ can be synthesized via water splitting for subsequent use in fuel cell or in an engine, it is not a convenient means to store solar energy. H₂ is highly volatile and therefore requires high pressure or cryogenic container to maintain a temperature of -253 °C. The handling of potentially explosive H₂ requires special conditions: high pressure, minimum diffusion or leakage and extensive safety precautions. Additionally, the volumetric energy density of liquid H₂ is about one-third of that of gasoline. Further, the infrastructure needed for H₂ fuel would be expensive, thus limiting its potential use. In order to overcome these issues, George A. Olah (Nobel Prize winner in Chemistry in 1994) proposed a “methanol economy”, wherein methanol can be used as a means of energy storage instead of H₂ and/or fossil fuels [24]. Methanol production for methanol economy can be synthesized by solar water splitting in the presence of CO₂, as discussed below.

9. Solar Water Splitting for CO₂ Reduction

Solar water splitting not only has the potential to mitigate the energy crisis but also has the capability to reduce CO₂ in the environment. The four electrons and the four holes released from water oxidation reaction (Eq-1) can be combined with CO₂ to produce liquid alcohol or hydrocarbon fuel (CO, CH₄ or CH₃OH) [13], as follows [25]:

CO₂ + 6e^- + 6H⁺ → CH₃OH + H₂O                ………………. (3)

Liquid fuel (i.e., CH₃OH) can also be produced by catalytic hydrogenation of CO₂ and H₂, wherein H₂ is obtained from solar water splitting, as follows [25]:

CO₂ + 3H₂ → CH₃OH + H₂O                    …….. ……….. (4)

The produced Methanol can be used directly in a “Direct Methanol Fuel Cell”. The required CO₂ for the above reactions can be captured from fossil fuel burning power plants or other industries. Considering the diminishing fossil fuel resources and therefore CO₂, the CO₂ in air can also be used for the above reactions. Since the concentration of CO₂ in air is very low (0.037%) [26], new technologies need to be developed to efficiently and economically capture CO₂ from air.

Figure 5: Schematic diagram of solar water splitting for energy production and environment purification.

Therefore, environment purification (i.e., CO₂ reduction) and energy production (i.e., liquid fuel) can be achieved simultaneously, as shown schematically in Figure 5. Because of their higher volumetric energy densities, hydrocarbon fuels can alleviate hydrogen storage issues. Further, hydrocarbon fuels can be used in existing gasoline infrastructure with limited modifications [26]. Hence, building expensive liquid H₂ infrastructure can be avoided. Therefore, there is an immense potential in solar water splitting both for carbon-free energy and environment. Research and development in this area are under advancement.

10. Current Technological Challenges

The major technological challenges for the large scale deployment of solar water splitting either for H₂ generation or for CO₂ reduction may be summarized as follows: (1) development of stable, highly efficient and visible light active photocatalyst from Earth abundant materials for water oxidation and reduction; (2) development of stable and efficient catalyst for CO₂ reduction; (3) development of a technology to separate simultaneously produced H₂ and O₂ from solar water splitting; (4) development of new materials to store large amounts of H₂ in a small volume at low pressure, near-ambient temperature, and with high efficiency during energy release cycle. Success in addressing these technological challenges will enable a carbon-free clean planet wherein there will be no energy crisis, no geopolitical instability and therefore a peaceful humanity.

11. Conclusions

Solar energy is the ultimate solution to mitigate the current and future energy crises. However, for widespread market penetration, solar energy has to be harnessed more efficiently and stored for large scale long-term applications. Solar water splitting allows producing H₂ gas, a clean, renewable and carbon-free energy carrier. Solar water splitting can also be used for CO₂ reduction from environment with simultaneous production of hydrocarbon fuel. However, many significant challenges need to be addressed for translating this technology from R&D laboratory to the commercial world. How soon this technology will reach marketplace depends on how soon breakthroughs are made in discovery research.

12. References:

[1] Energy Information Association; U.S. Department of Energy: Washington DC; Retrieved 22 June, 2012 from www.eia.doe.gov.

[2] 2009 World Population Data Sheet; Population Reference Bureau: Washington, DC, 2009; Retrieved 22 June, 2012 from www.prb.org

[3] Power Division, Ministry of Power, Energy and Mineral Resources, Bangladesh, Retrieved 22 June, 2012 from  http://www.powerdivision.gov.bd/user/welcome

[4] Bangladesh Power Development Board (BPDB), Retrieved 19 June, 2012 from http://www.bpdb.gov.bd/bpdb/

[5] J. R. Bolton, D. O. Hall, Annu. Rev. Energy, 4, 353 (1979).

[6] S. Ansolabehere et al. The Future of Nuclear Power; MIT Press: Cambridge, MA, 2003.

[7] D. Abbott, Proc. IEEE, 98, 42 (2010).

[8] K. Rajeshwar, R. McConnell, S. Licht, Solar Hydrogen Generation: Toward a Renewable Energy Future, Springer, 2008.

[9] A. J. Nozik, Inorg. Chem. 44, 6893 (2005).

[10] J. A. Turner, M. C. Williams, K. Rajeshwar, The Electrochemical Society Interface, Fall 2004.

[11] T. R. Cook et al, Chem. Rev., 110, 6474 (2010).

[12] A. Fujishima, K. Honda, Nature 238, 37 (1972).

[13] A. Kudo, Y. Miseki, Chem. Rev., 38, 253 (2009).

[14] Z. G.  Zou, J. Ye, K. Sayama, H. Arakawa, Nature 414, 625 (2001).

[15] K. Maeda, J. Photochemistry and Photobiology C: Photochemistry Reviews. 12, 237 (2011).

[16] D. Wang, Nano Lett., 11, 2353 (2011).

[17] K. Maeda, K. Domen, J. Phys. Chem. C, 111, 7851 (2007).

[18] X. Chen, S. Shen, L. Guo, S. S. Mao, Chem Rev.  110, 6503 (2010).

[19] Shahed U. M. Khan, Mofareh Al-Shahry, William B. Ingler Jr. Science 297, 2243 (2002).

[20] R. Asahi, T. Morikawa, T. Ohwaki, K. Aoki, Y. Taga, Science 293, 269 (2001).

[21] K. Maeda, et al. Nature, 440, 295 (2006).

[22] Y. Xia et al. Adv. Mater. 15, 353 (2003).

[23] K. Maeda, K. Domen, J. Phys. Chem. Lett. 1 2655 (2010).

[24] Beyond Oil and Gas: The Methanol Economy, George A. Olah, Alain Goeppert, G. K. Surya Prakash, Wiley-VCH, 2006.

[25] Maria Jitaru, J. University of Chemical Technology and Metallurgy, 42, 4 (2007).

[26] Retrieved on June 21, 2012 from http://en.wikipedia.org/wiki/Methanol_economy

AMEC Oil and Gas, Houston, USA

Email: samad.buet@gmail.com

Back to Basics–Technical Review : Received 28 April 2012; received in revised form 11 June 2012; online published 16 July 2012

The use of petroleum products play important role in modern civilization. Petroleum products are directly used for producing electric power, running vehicles, planes, ships etc., running engines for agricultural use and many other areas related to human benefits. In addition, petroleum products are used as raw materials to create products such as plastics, polyurethane, solvents, asphalt, and hundreds of other intermediate and end-user goods.

The word ‘petroleum’ is made up of the Latin words ‘petr’ and ‘oleum’. ‘Petr’ means rock and ‘oleum’ means oil. Petroleum means “rock oil” or “oil from the earth”. The oil is called so  because it is extracted from the rocks beneath the Earth, where it is formed from the evolution of accumulated fossils, over thousands of years.. The oil reserve is explored in the Earth and extracted from the economically recoverable reserves. The extraction process varies according to its location and formation in the Earth.

This article provides a brief overview of various resources of petroleum oil including the types of crude oil, and current worldwide reserves, petroleum oil facilities and petroleum industries.

1. Crude Oil

The stabilized liquid form of the oil extracted (or converted) from the reserve is called crude oil which is a complex mixture of various hydrocarbon products. Crude oil is generally not a directly useable petroleum product. It is further refined to produce hydrocarbon products such as liquefied petroleum gas (LPG), gasoline, diesel, kerosene, jet fuel, naphtha, furnace oil etc.

Crude oil is categorized on the basis of a number of criteria including ‘sulfur contents’, ‘API gravity’, ‘trading brand’ or ‘recovery methods’.

(a) Category by Sulfur Contents

Based on the amount of sulfur contents, the crude oil is called Sweet crude or Sour crude.

(1)Sweet Crude: The crude oil having a total sulfur level less than 0.5% is called Sweet crude. Sweet crude oil contains small amount of hydrogen sulfide and carbon dioxide.

(2) Sour Crude: The sour crude contains a sulfur level greater than 0.5%. Processing sour crude is usually expensive due to the additional process of removing the sulfur.

(b) Category by API Gravity

Depending on the API gravity ⁽¹⁾, the crude oil is categorized as Heavy, Light and Medium crude.

(1) Heavy Crude: Heavy crude oil or Extra Heavy Crude oil is any type of crude oil which does not flow easily. It is called heavy because its density or specific gravity is higher than that of light crude oil. The API gravity of Heavy crude oil is lower than 22 degree.

(2) Light Crude: Light crude oil is liquid petroleum that has a low density and flows freely at room temperature. It has a low viscosity, low specific gravity and high API gravity (greater than 31 degree). It generally has low wax content. Light crude oil produces higher percentage of gasoline and diesel fuel when converted into products by an oil refinery.

(3) Medium Crude: It is the crude oil which falls in between Heavy and Light Crude oil. The API gravity of medium crude oil is less than 31 degree and greater than 22 degree.

Both of the above categories are used to characterize the Crude Oil, such as ‘Light Sweet’ crude, ‘Heavy Sour’ crude, ‘Medium Sweet’ crude etc.

(c) Category by Trading Brand

Crude oil is classified by the trading brand when traded in the oil market. Each trading brand of crude is characterized by the specific properties. Crude oil produced from reservoirs of different geographical locations has different characteristics. So, the trading brand of the crude is generally named for a specific area of its production. Some of the major benchmark trading brands of crude are:

(1) Brent Crude: Brent Crude is sourced from the North Sea. Originally Brent Crude was produced from the Brent oil field. Brent is suitable for production of gasoline and middle distillates. It is typically refined in Northwest Europe. Brent Crude has an API gravity of around 38.06 degree and a specific gravity of around 0.835.

(2) WTI (West Texas Intermediate): It is also known as Texas Light crude. WTI is used as a benchmark of oil pricing. For WTI crude, the API gravity is around 39.6 degree, specific gravity is about 0.827 and the sulfur content is about 0.24%.

(3) ORB (OPEC Reference Basket or OPEC Basket): This is the common brand name for the crude produced and used as a price reference by OPEC countries. It consists of many other brands such as Saharan Blend (Algeria), Iran Heavy, Basra Light (Iraq), Kuwait Export, Es Sider (Libya), Qatar Marine, Arab Light, Murban (UAE) and BCF 17 (Venezuela). The OPEC Basket, which is a mix of light and heavy crudes, is heavier than both Brent crude oil and West Texas Intermediate crude oil.

(4) Dubai Crude: It is a light sour crude oil extracted from Dubai. Dubai Crude is used as a price benchmark or oil marker because it is one of the few Persian Gulf crude oils available immediately. Dubai Crude is light oil. It has an API gravity of 31 degree (sp. gr. of 0.871) and a sulfur content of 2%.

However, Brent and WTI are the major benchmark trading crudes and others follow these two brands by either adding premium or discount.

(d) Category by Source and Recovery Method

Crude oil is also categorized as Conventional and Unconventional according to the recovery methods and techniques from its reservoir or from the materials containing it.

(1) Conventional crude oil: Conventional crude oil is that which is recoverable from the reservoir through production well using standard production methods and techniques which include
• Crude flows to the surface under the pressure of the reservoir,
• Crude flows to the surface with certain pressure applied to the reservoir, or
• Crude flows to the surface with artificial lift method and technique such as submersible pumps, over-ground pump-jack, etc.

Conventional crude oil exists in the liquid phase under normal surface temperature and pressure. It also has the ability to flow through the rock within the reservoir.

(2) Unconventional crude oil: Unconventional crude oil is produced or extracted using the methods and techniques other than the conventional methods. The unconventional crude is generally heavy oil, extra heavy oil or bitumen. Unconventional oil production is less efficient, more expensive and has more environmental impacts than conventional oil production. The examples of unconventional oil are oil-sands, shale oil, CTL (Coal-to-Liquid), GTL (Gas-to-Liquid) etc.

(e) Synthetic crude oil (SCO)

There is another sort of crude called synthetic crude oil (SCO). Synthetic crude oil is not the directly extracted crude from the reservoir; it is the crude which is produced by a chemical conversion process from products of the unconventional sources of oil.

2. Conventional Oil Resource

The oil of conventional reserve remains in liquid form with the mixture of water and gas within the reservoir and it is economically recoverable with relatively simple techniques.  The resources of conventional oil are broadly classified as Onshore and Offshore, based on the location of the reservoir. Onshore oil reservoirs are located in land surface, whereas offshore oil reservoirs are located in seafloor underneath the sea water.

(a) Onshore

Onshore (land based) conventional oil is the most economical type of oil reserves. Most of the world’s largest onshore oilfields are located in the Middle East (Figure 1), but there are also large oilfields located in Brazil, Mexico, Venezuela, Kazakhstan and Russia. The large onshore oil fields are Ghawar ⁽¹⁾ (Saudi Arabia), Khurais (Saudi Arabia), Shaybah (Saudi Arabia), Burgan (Kuwait), Dukhan (Qatar), Kirkuk (Iraq), Rumaila (Iraq), Ferdous (Iran), Azadegan (Iran), Esfandiar (Iran), Sugar Loaf (Brazil), Cantarell (Mexico), Bolivar Coastal (Venezuela), Tengiz (Kazakhstan), Kasaghan (Kazakhstan) etc.

 

Figure 1: Oil fields (including Ghawar, Khurais and Dukhan field) near Arabian Gulf. (Courtesy: Greg Croft Inc, website, www.gregcroft.com/area1indexmap.ivnu)

(b) Offshore

Offshore crude oil production started in the 1940s and has grown from 1 million barrels a day (mb/d) in the 1960s to nearly 25 mb/d in 2005. At this time, the offshore oil production is almost half of onshore production worldwide. It has been the main source of growth for world oil production as the onshore oil production has remained almost flat for the last few decades. Offshore oil production is more challenging than onshore due to the remote and harsher environment. However, the technology for offshore oil production facilities is improving and it is now feasible to extract oil from shallow and deep water.

Currently, there are several types of offshore production facilities (rigs) in production and they are Fixed Platform, Compliant Tower, Spar, TLP (Tension Leg Platform), Semi-Submergible, FPSO (Floating, Production, Storage and Offloading), as well as the Subsea Processing system. Most of the existing offshore oil production facilities are shown in Figure 2 (the fixed platform and compliant tower which are used for shallow water are not shown). The major offshore oil production areas are the Gulf of Mexico (GOM), West Africa, North Sea, Persian Gulf, Southeast Asia, Australia, Brazil and Canada (Newfoundland).

Figure 2: Worldwide Offshore Oil Production facilities (Courtesy: Mustang, OTC – 2010, Houston, USA).

3. Unconventional Oil Resource

The unconventional resources are those other than the conventional resources and the oil is extracted from the sources, applying relatively complex processes. The major resources of unconventional oil are oil-sands, oil shale, CTL (Coal-to-Liquid), GTL (Gas-to-Liquid), BTL (Biomass-to-Liquid) etc.

(a) Oil Sands

One of the major unconventional oil sources is ‘Oil Sands’. Oil sands are a combination of sand, bitumen, mineral rich clays and water. The exact proportions of these constituents vary from deposit to deposit. They are found in large amounts in many countries throughout the world such as Canada, Venezuela, USA and Russia. However, the largest deposits are in Canada and Venezuela. The product extracted from the oil sands is heavy and it is primarily the bitumen which is either upgraded to the synthetic crude oil (SCO) or diluted with lighter oil products to make it transferable to downstream through the pipeline.

In Canada, the bulk oil sands reserves are located in the north-east part of the province Alberta (Figure 2). The oil sands in northern Alberta constitute of the largest hydrocarbon reserves in the world. It is estimated that the total amount of bitumen is over 1.6 trillion barrels. There are three major deposits in Alberta – (1) Cold Lake, (2) Athabasca (Fort McMurray area) and (3) Peace River. Alberta oil sands are approximately 75%-80% inorganic materials (sand, clay and minerals), 3%-5% water with bitumen content ranging from 10% to about 18%. The key characteristic of Alberta oil sands is that the bitumen is encapsulated by water molecules and this makes them economically recoverable.

Figure 3: Alberta Oil Sands (Source: Wikipedia website en.wikipedia.org/wiki/Athabasca_oil_sands)

There are two primary methods used for extracting the oil from the oil sands: Surface Mining and In-Situ. In surface mining, the oil sands are collected from the earth surface and processed for extracting oil from the sands. In the In-Situ method, the oil is extracted directly from sands while the sands remain in their original location beneath the earth. There are various techniques applied for In-Situ methods such as Cold Flow, SAGD (Steam Assisted Gravity Drainage), CSS (Cyclic Steam Stimulation), VAPEX (Vapor Extraction Process), THAI (Toe to Heel Air Injection) etc.

(b) Shale Oil

‘Oil shale’ is an inorganic rock (Figure 4) that contains a solid organic bituminous compound known as ‘Kerogen’. When the oil shale is heated, petroleum-like liquids are released and it is converted into synthetic crude through chemical process of ‘Pyrolysis’. This crude is called ‘Shale oil’.

Extracting oil from oil shale is more complex and expensive than conventional oil recovery. The oil substances in oil shale are solid and cannot be pumped directly out of the ground. The oil shale is first mined and then heated to a high temperature to produce liquids. This method is called retorting. An alternative in-situ method is currently under experiment.

There are almost 600 known oil shale deposits around the world, of which many require more exploration to determine their potential reserves. However, worldwide technically recoverable reserves have recently been estimated at about 2.8 to 3.3 trillion barrels of shale oil, with the largest reserves in the United States (Colorado, Utah and Wyoming). Another major oil shale deposit in the US is the Bakken shale that starts from Saskatchewan (Canada) and ends in North Dakota (US). Other major deposits exist in Brazil, Australia, Sweden, Estonia, Jordan, France, Germany, China, and Russia.

The production of shale oil is significantly in progress in China, Estonia, Brazil, Australia, Morocco and Jordan, while few pilot projects are under experiment for the in-situ recovery technique in the US.

Figure 4: Oil Shale (Source: Programmatic EIS website: ostseis.anl.gov/guide/photos/index.cfm)

(c) CTL (Coal-to-Liquid)

Converting coal to liquid (CTL) fuel allows coal to be utilized as an alternative to fuel oil. There are two different methods of converting coal into liquid fuels:

(1) Direct Liquefaction: It works by breaking coal down in a solvent at high temperature and pressure. This process is efficient, but the liquid products require further refining to achieve high grade fuel characteristics.

(2) Indirect Liquefaction: It involves first gasifying the coal into synthesis gas or syngas, a mixture of hydrogen and carbon monoxide, and then converting the syngas to synthetic fuels (Figure 5). Using modern technology, indirect liquefaction produces environmentally compatible high quality and clean products.

Conversion ratios for CTL are generally estimated to be between 1 to 2 barrels/ton of coal. The ratio is affected by different properties of the coal feedstock.

South Africa has been producing CTL fuels commercially since 1955 and almost 30% of the country’s gasoline and diesel needs are produced from coal. CTL is being developed for industrial scale production in China and by other major industrial countries.

The world’s biggest reserves of coal are (in billion tones or giga-tones) in the United States (242.6, 29%), Russia (157, 18%), China (114.5, 13%), Australia (76.5, 9%), India (56.6, 7%), South Africa (48, 6%).

(d) GTL (Gas-to-Liquid)

Gas to liquids (GTL) is the process to convert natural gas or other gaseous hydrocarbons into liquid fuel such as gasoline or diesel using direct conversion or via syngas as an intermediate product with either the Fischer Tropsch or Mobil processes (Figure 5).

Figure 5: CTL/GTL/BTL Conversion (Source: Wikipedia website en.wikipedia.org/wiki/Synthetic_fuel)

The commercial GTL production (14,700 barrels per day) started in Bintulu GTL plant in Malaysia in 1993. The recent development for GTL is the Pearl GTL project in Qatar. The production from the first Pearl GTL train was started in June 2011. Full production from the plant is expected by the middle of 2012. The plant is designed for  a capacity of  300,000 barrels per day of synthetic fuels and other products, using natural gas as a feedstock.

(e) BTL (Biomass-to-Liquid)

BTL is not a petroleum product; it is rather an alternative source of petroleum oil. Biomass is the biological material derived from wood, waste, forest residues, yard clippings, wood chips, municipal and animal waste, crops like corn and sugar cane etc. BTL is the synthetic liquid fuels obtained from biomass through a thermo chemical process (Figure 5). It is a multi-step process to produce liquid fuels from biomass. The objective of BTL is to produce fuel components that are similar to the fossil-derived gasoline and diesel fuels.

There are primarily three types of liquid fuels produced from biomass: Biodiesel, Bioethanol and Biobutanol.

(1) Biodiesel: It is made from vegetable oils, animal fats or recycled greases. Biodiesel can be used as a fuel for vehicles in its pure form, but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles. Biodiesel is the most common biofuel in Europe.

(2) Bioethanol: Bioethanol is the alcohol made by fermenting sugar components of plant materials and it is made mostly from sugar and starch crops. Ethanol is usually used as a gasoline additive to increase octane number and improve vehicle emissions. Bioethanol is commonly used in the USA and in Brazil.

(3) Biobutanol: It is a four-carbon alcohol derived from the fermentation of biomass. It has been demonstrated to work, without modifications, for vehicles designed to run on gasoline without modification and it is used as a fuel in an internal combustion engine. Because of its certain advantages over other biofuels, it is considered to be the primary biofuel for the next generation.

The global biofuels market consists of approximately 85% bioethanol and 15% biodiesel. Bioethanol is produced and consumed mainly in Brazil and North America. On the other hand, Europe is the world leader in biodiesel production and this fuel represents about three-fourth of the European biofuels market.

4. Proven Oil Reserves and Daily Production

(a) Proven Oil Reserves

Proven reserves of oil are those reserves which are claimed to have at least 90% certainty of being recoverable using existing technology under existing economic, environmental and political conditions. It is also called P90 (because of 90% certainty of being produced) or 1P.

According to the OPEC Statistical Bulletin 2010/2011 Edition ⁽³⁾, the total worldwide proven oil reserve is 1,637 billion barrels (Bb) including Canadian oil sands of 170 Bb. The reserve of the OPEC countries is almost 80% of the worldwide reserves.

The major oil reserve countries (having larger than 5 Bb reserve in 2010) with the reserve quantities (rounded to nearest Bb) are: