Description
ABSTRACT
Renewable and clean forms of energy are one of society’s greatest needs. At the same time, 2 billion people in the world lack adequate sanitation and the economic means to afford it. Abundant energy, stored primarily in the carbohydrates can be found in waste biomass, agricultural, municipal and industrial sources as well as in dedicated energy crops. A microbial fuel cell is a device that directly converts the metabolic and enzyme catalytic energy to electricity by using conventional electrochemical technology. Chemical energy can be converted into electricity by coupling of biocatalytic oxidation of organic or inorganic compounds to the chemical reduction of an oxidant at the interface between cathode and anode.
TABLE OF CONTENTS
COVER PAGE
TITLE PAGE
APPROVAL PAGE
DEDICATION
ACKNOWELDGEMENT
ABSTRACT
CHAPTER ONE
- INTRODUCTION
- BACKGROUND OF THE PROJECT
- PROBLEM STATEMENT
- OBJECTIVE OF THE STUDY
- SIGNIFICANCE OF THE STUDY
- SCOPE OF THE STUDY
- APPLICATION OF THE STUDY
- THE FUTURE OF MFC RESEARCH
- RESEARCH ORGANISATION
CHAPTER TWO
LITERATURE REVIEW
- REVIEW OF MICROBIAL (BATERIA) FUEL CELL
- HISTORICAL BACKGROUND OF THE STUDY
- DEFINITION MICROBIAL FUEL CELL
- REVIEW OF DIFFERENT TYPES MICROBIAL CELLS
CHAPTER THREE
METHODOLOGY
- GENERATION PROCESS
- SYSTEM CONPONENTS
- SYSTEM SETUP DIAGRAM
- WORKING PRINCIPLE
CHAPTER FOUR
- RESULT ANALYSIS
- SUBSTRATES AND THEIR PERFORMANCE VALUES
- BACTERIA POWERED FUEL CONFIGURATION
- TYPES OF BACTERIA POWERED FUEL
- WASTEWATER TREATMENT
CHAPTER FIVE
- CONCLUSION
- SUMMARY
- REFERENCES
CHAPTER ONE
1.0 INTRODUCTION
1.1 BACKGROUND OF THE PROJECT
In the recent decades, consumption of energy within the world has had a prosperous trend Energy sources are classified into three batches: fossil fuels, renewable sources and nuclear sources, in which non-renewable sources of energy, which include an enormous portion of energy consumption, could be categorized into two major classifications: nuclear and fossil energy Fossil fuels negatively influence the nature owing to the emission of carbon dioxide. It follows logically from what has been said that the consumption of fossil fuels has severely imperiled human life through its drastic aftermaths, such as global warming and atmospheric pollution
However, miscellaneous countries around the world have made remarkable efforts to find a piece of cogent solution for energy crisis by turning the eyes into renewable energy sources such as solar energy, energy produced from wind and water. As an upshot of these efforts, one of the latterly proposed alternative energy sources is fuel cell (FC) which generates energy using high value metal catalysts (in the traditional version). In actual fact, FC is of plethora advantages over other kinds of energy generators, e.g. no emissions of environmental polluting gases (such as SOx, NOx, CO2 and CO), higher efficiency, no existence of mobile parts, as a result, lack of sonic pollution, and so forth. In contrast, high cost and high mass generation are the only disadvantages of these new energy sources and.
One type of FCs is microbial fuel cell (MFC) that uses an active microorganism as a biocatalyst in an anaerobic anode compartment for production of bioelectricity and.. Although electrical current produced by bacteria was observed by Potter in 1911, limited feasible results were acquired in this area by the next 50 years. However, in the early 1990s, FCs became far more appealing devices; consequently, MFCs were considered as promising technology.
This work is based on bacteria powered fuel or microbial fuel cell (MFC) which is a bio-electrochemical device that harnesses the power of respiring microbes to convert organic substrates directly into electrical energy. At its core, the MFC is a fuel cell, which transforms chemical energy into electricity using oxidation reduction reactions. The key difference of course is in the name, microbial fuel cells rely on living biocatalysts to facilitate the movement of electrons throughout their systems instead of the traditional chemically catalyzed oxidation of a fuel at the anode and reduction at the cathode.
1.2 PROBLEM STATEMENT
The disposal of municipal solid wastes is one of the most serious problems facing the 21st century. Waste generation is on the increasing trend due to exponentially increasing population growth, which renders waste management as a significant problem. The solid waste generation (lb/capita/day) has been on increasing trend since 1980, with the current value reaching as high as 1 lb. per capita/day. New York State alone generates 8.4 million tons of municipal solid waste per year and are rapidly approaching their limit for the built and permitted capacity of new landfills. On the Campus, food waste has become an increasingly large issue. In the Our dining hall on campus alone, an estimated 4 to 10% of food prepared ends up in the trash. While Our dining hall is making efforts on select campuses across the country to reduce this waste, we remain unaffected.
With Our dining hall serving over 3300 students, food waste generated on campus is around 3300 pounds per day. Over the course of a school year, this means we are throwing away over 330 tons of food. As such, it is essential that this food waste be reduced. To bring the campus waste treatment up to modern standards, we propose an investigation into a series of biological treatment processes. These processes which, when combined; could drastically contribute to our waste disposal problem. First, the biological treatment processes of bio- hydrogen fermentation, in dark and acidic conditions, can process complex organic substrates into a simpler, more homogenous mixture of short-chain fatty acids, such as acetic acid and butyric acid. This can be followed by a digestion in a microbial fuel cell, which further coverts the remaining chemical energy into usable electrical current while simultaneously treating water.
1.3 OBJECTIVE OF THE STUDY
This work discuses a means generating electricity using bacteria and mimicking bacterial interactions found in nature.
1.4 SIGNIFICANCE OF THE STUDY
The new device relies on natural biological processes of so-called electric bacteria, essentially living cells that eat and breathe electricity.
“These electric bacteria are a fascinating type of bacteria that are capable of transferring electrons generated by the breaking down of organic compounds extra-cellularly,”
This work is a means of generating electricity at low cost, which could help with combatting dependence on fossil fuels.
The device is also carbon-neutral, according to the researchers, which means no additional carbon dioxide is released into the atmosphere when it operates. The cost-effectiveness of the materials used, the zero emission of harmful gasses, and the use of waste as fuel with the additional advantage of treating waste while generating electricity all contribute to how the device can support secure, affordable and environmentally friendly energy,
1.5 SCOPE OF THE STUDY
Bacteria have evolved to utilize almost any chemical as a food source. In the microbial fuel cell, bacteria form a biofilm, a living community that is attached to the electrode by a sticky sugar and protein coated biofilm matrix. When grown without oxygen, the byproducts of bacterial metabolism of waste include carbon dioxide, electrons and hydrogen ions. Electrons produced by the bacteria are shuttled onto the electrode by the biofilm matrix, creating a thriving ecosystem called the biofilm anode and generating electricity.
1.6 APPLICATION OF THE STUDY
Power generation
MFCs are attractive for power generation applications that require only low power, but where replacing batteries may be impractical, such as wireless sensor networks.
Virtually any organic material could be used to feed the fuel cell, including coupling cells to wastewater treatment plants. MFCs are a clean and efficient method of energy production. Chemical process wastewater and synthetic wastewater have been used to produce bioelectricity in dual- and single-chamber mediatorless MFCs (uncoated graphite electrodes).
Higher power production was observed with a biofilm-covered graphite anode. Fuel cell emissions are well under regulatory limits. MFCs use energy more efficiently than standard internal combustion engines, which are limited by the Carnot Cycle. In theory, an MFC is capable of energy efficiency far beyond 50%. Rozendal obtained energy conversion to hydrogen 8 times that of conventional hydrogen production technologies.
However; MFCs can also work at a smaller scale. Electrodes in some cases need only be 7 μm thick by 2 cm long. Such an MFC can replace a battery. It provides a renewable form of energy and does not need to be recharged.
MFCs operate well in mild conditions, 20 °C to 40 °C and also at pH of around 7. They lack the stability required for long-term medical applications such as in pacemakers.
Power stations can be based on aquatic plants such as algae. If sited adjacent to an existing power system, the MFC system can share its electricity lines.
Education
Soil-based microbial fuel cells serve as educational tools, as they encompass multiple scientific disciplines (microbiology, geochemistry, electrical engineering, etc.) and can be made using commonly available materials, such as soils and items from the refrigerator. Kits for classrooms and hobbyists and research-grade kits for scientific laboratories and corporations are available.
Biosensor
The current generated from a microbial fuel cell is directly proportional to the energy content of wastewater used as the fuel. MFCs can measure the solute concentration of wastewater (i.e., as a biosensor).
Wastewater is commonly assessed for its biochemical oxygen demand (BOD) values. BOD values are determined by incubating samples for 5 days with proper source of microbes, usually activated sludge collected from wastewater plants.
An MFC-type BOD sensor can provide real-time BOD values. Oxygen and nitrate are preferred electron acceptors over the electrode, reducing current generation from an MFC. MFC BOD sensors underestimate BOD values in the presence of these electron acceptors. This can be avoided by inhibiting aerobic and nitrate respiration in the MFC using terminal oxidase inhibitors such as cyanide and azide. Such BOD sensors are commercially available.
Biorecovery
In 2010, A. ter Heijne et al. constructed a device capable of producing electricity and reducing Cu (II) (ion) to copper metal.
Microbial electrolysis cells have been demonstrated to produce hydrogen.
Wastewater treatment
MFCs are used in water treatment to harvest energy utilizing anaerobic digestion. The process can also reduce pathogens. However, it requires temperatures upwards of 30 degrees C and requires an extra step in order to convert biogas to electricity. Spiral spacers may be used to increase electricity generation by creating a helical flow in the MFC. Scaling MFCs is a challenge because of the power output challenges of a larger surface area.
1.7 THE FUTURE OF MFC RESEARCH
Humanity has only touched the surface of MFC capability. As our understanding of microbial metabolisms, genomics, and genetic modification deepens, better exoelectrogens are produced and new applications are discovered. Currently, the size of MFCs is limited by the fact that electron transport only occurs in a bacteria layer immediately in contact with the electrodes. So while MFCs have seen success in large scale batch processing of waste water streams, their true potential lies in small scale devices where the surface to volume ratio is high. There exists an optimal flow rate of reactants for increasing the voltage output of an MFC. Advances in microfluidics will allow engineers to make increasingly smaller MFC devices that can take advantage of this high surface to volume ratio. Research into advanced microfluidics, bacterial strains, more robust separator membranes, and efficient electrodes are the key to unlocking the potential of MFCs.
1.8 PROJECT ORGANISATION
The work is organized as follows: chapter one discuses the introductory part of the work, chapter two presents the literature review of the study, chapter three describes the methods applied, chapter four discusses the results of the work, chapter five summarizes the research outcomes and the recommendations.
Reviews
There are no reviews yet.