Department of Energy Science and Engineering (ESE)
http://hdl.handle.net/20.500.12228/44
2024-03-29T07:15:40ZRecovery and Characterization of Fuel from Pyrolysis of Medical Wastes: An Alternative Source of Energy
http://hdl.handle.net/20.500.12228/896
Recovery and Characterization of Fuel from Pyrolysis of Medical Wastes: An Alternative Source of Energy
Abedeen, Adnan
Bangladesh is a developing country and one of the most densely populated countries in the world. Energy consumption per capita of this country is also low compared to other developing nations. At present, the energy demands are becoming acute day by day. Environmental concerns and energy insufficiency led the government of the developing countries to think about innovative and nonconventional energy sources. Renewable energy sources may be a possible solution for meeting ever increasing energy demand as well as a way out of increasing environmental pollution. Various waste materials created from different sectors such as agricultural, industrial or medical sectors may also contribute to these matters. Inorganic materials like tyre waste are already contributing as a potential source of energy by deriving liquid and solid fuels through pyrolysis.
Appropriate and safe management of medical waste is acknowledged globally. Syringe/saline bottle wastes are mainly polyethelene and polypropelene plastic which are non-biodegradable and can create environmental pollution. Various typical problems are created to our surroundings by the disposal of such medical wastes. Sustainable management of such waste is important from various considerations. Lack of proper supervision of medical waste can cause some severe problems. The dumping of medical waste (syringe/saline bottle) into the drain is one of the main environmental issues in the municipal/city areas of Bangladesh. Blockage of drain and generation of mosquitoes and other bacteria are favoured by the disposal of such wastes in unplanned manner. The unmanaged recycling of infectious syringes and saline bottles represent a big threat to public health. Such circumstances are very likely to occur when medical waste is dumped in open space. Street children are chiefly at risk to come in contact with such wastes. Besides health-risk originated from direct contact, medical waste can harmfully affect the ecosystem by polluting water-bodies during waste treatment. Also, when such wastes are discarded in open areas close to water-bodies, they may become contaminated. So, deliberately this matters to the authority and researchers to manage these nonbiodegradable waste materials. So, a way to manage waste as well as extraction of fuel may be a good solution to this problem.
Management of medical waste is the accurate constraint, storage, treatment and dumping of infectious waste produced at human and animal health-care facilities. Adequate treatment procedures of medical waste are processes or techniques specifically designed to change the biological nature and composition/structure of medical waste. If this is done effectively, the wastes will no longer be contagious or biologically hazardous. The safe discarding and treatment of medical wastes have been ignored in Bangladesh. Land filling is largely used to manage medical waste which is not an appropriate option as dumped plastic wastes can cause serious damage to environment.
It is a shocking situation that waste produced inside the health-care facilities are collected by untrained cleaners without any separation in almost every city of Bangladesh. Then the cleaners dumped them into a hole or city corporation dustbin. Waste collectors use open basket or plastic bowl. Medical wastes are discarded in some open places, whereas rest of the waste is taken at the city corporation burning area. Open burning of medical waste is causing serious air pollution. Therefore, pyrolysis process can be a promising way out of this crisis. It will indirectly help to manage such non-biodegradable wastes, also low grade liquid fuels can be obtained. When waste materials are pyrolyzed, they generate oil, char and gas, which are valuable. The oil and char has adequate calorific value and can be used to produce heat energy.
In the present research, waste syringe/saline bottle were collected from the local clinics and hospitals of Khulna city areas and were pyrolyzed in a batch type reactor. Experiments on pyrolysis of syringe/saline bottles were conducted by changing the temperature within the range of 150-250° C at an interval of 50° C. The batch type fixed-bed pyrolysis reactor was constructed and installed in the Heat Engine Laboratory of the Department of Mechanical Engineering, Khulna University of Engineering & Technology. The maximum yield of pyrolytic oil and pyrolytic char from syringe waste was 35.94% (by weight) at 250° C and 51.08% (by weight) at 150° C with the feed size of 2×2 cm with loading size of 1.5 kg. The maximum yield of pyrolytic oil and pyrolytic char from saline bottle waste was 36.14% (by weight) at 250°C and 51.15% (by weight) at 150°C with the feed size of 2×2 cm with loading size of 1.5 kg.
The properties of pyrolytic oil from waste syringe/saline bottle such as density, kinematic viscosity, pour point, boiling point and cloud point were measured and the respective values are in the range of 726 to 758kg/m3 , 3.19 to 4.75cSt, -12 to -16° C, 86 to 95° C, -2 to 5°C and the gross calorific value (GCV) is around 42-44 MJ/kg which is comparable to diesel (42 to 46 MJ/kg). The GCV of pyrolytic char is around 42-43 MJ/kg which is comparable to anthracite coal (23 to 24 MJ/kg). The Gas chromatography-mass spectrometry (GC-MS) and Fourier Transform Infra-Red (FTIR) tests suggest presence of higher amount of aromatic compounds in pyrolytic oils evolved from the pyrolysis of syringe/saline bottle waste. The Thermogravimetric Analysis (TGA) shows that the experimental curve is higher from 150 to 300°C. The oil and char obtained from pyrolysis of syringe/saline bottle waste can be used as alternative fuel or chemical feedstock after some treatment. The results show that these properties are similar to that of the low grade liquid fuels and high grade solid fuels and thus pyrolysis of such waste (syringe/saline bottle) will reduce environmental contamination to a degree as well as be a substitute source of energy.
This thesis is submitted to the Department of Energy Science and Engineering, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering, December 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 80-88).
2019-12-01T00:00:00ZProduction of Liquid Fuel from Rice Husk and Sawdust
http://hdl.handle.net/20.500.12228/544
Production of Liquid Fuel from Rice Husk and Sawdust
Islam, Md. Kamrul
Energy is the key input to economic growth of a nation and there is a close relation between
accessibility of energy and escalation in the quality of nation. As conventional energy sources
are limited and will diminish in future after complete consumption, so it is the high time to deal
with the renewable and non-conventional energy sources. The necessity of liquid fuel is not only
in the transport sector rather it is required in industrial and power sector. Production of liquid
fuel from ligno-cellulosic material is one of the sources of renewable energy. As Bangladesh is
an agricultural country, rice husk and sawdust are the common sources among all sources of
cellulosic material available in the country. In the present study, fermentation method is used to
produce liquid fuel from rice husk and sawdust. For fermentation process simultaneous
saccharification and fermentation (SSF) process being used. In the process, husk and sawdust
was pretreated to neutralize it and then saccharification was carried out with cellulase enzyme
with different proportion where temperature was maintained at around 37oC for 84 hours.
Fermentation reagents were prepared by adding yeast, peptone and dextrose for yeast inoculums.
Saccharified slurry was clutched to fermentation in a mixture of reagents and fermentation
medium. The process was carried out for one day in aerobic condition and then next three days in
anaerobic condition at a temperature of 35oC. After fermenting clear supernatant is obtained
from centrifugation and then gas chromatography (GC) was performed on the product for
estimation of ethanol. In the experimentation rice husk and enzyme mixture was added at the
ratios of 2.5:1, 3:1 and 3.5:1 respectively. The yields of ethanol are respectively 9.55% (v/w),
8.73% (v/w) and 6.74% (v/w) from respective fermented liquid broth. Sawdust and enzyme ratio
of 2.5:1 provide a very low about 1.23% (v/w) of ethanol. This shows that sawdust not
prospective but rice husk is a prospective source of extraction of liquid fuel by fermentation.
This thesis is submitted to the Department of Energy Science and Engineering, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Energy Science and Engineering, May 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 56-62).
2019-05-01T00:00:00ZPyrolysis of Organic Waste: A Way to Solid Waste Management and Extraction of Fuel
http://hdl.handle.net/20.500.12228/539
Pyrolysis of Organic Waste: A Way to Solid Waste Management and Extraction of Fuel
Nipa, Farzana Yeasmin
Bangladesh is a developing country and is one of the most densely populated countries in
the world. Her per capital energy consumption is also low compared to others. At present,
the energy demands are becoming more acute day by day. Environmental issues and
energy scarcity led the government of the developing countries to think about new and
alternative energy resources. Renewable energy resources may be one kind of alternative
energy. Various waste materials derived from agriculture or industrial sectors can
contribute to these issues. Tyre wastes, mixture of organic and inorganic materials, already
become potential source to derive liquid fuel as well as solid fuels by pyrolysis.
Shoe/sandal soles have similar compositions like tyres and also create environmental
pollution problems. Rubber containing wastes such as shoe/sandal soles are solid waste
which is non-biodegradable and with increased production of shoe/sandal, the volume of
waste soles will also be increased. Some typical problems are created to the environment
as well as to our surroundings by the disposal of such wastes. The dumping of waste
(shoe/sandal soles) in the drain is one of the main environmental issues in the
municipal/city areas of Bangladesh. Blockage of drain and generation of mosquitoes or
other bacteria are favored by the disposal of such wastes in unplanned manner. So,
deliberately this matters to the authority and researchers to manage these nonbiodegradable
waste materials (soles of shoe/sandal). So, a way to manage waste as well as
extraction of fuel may be a good solution to this problem.
Under the circumstances, extraction of fuel from shoe/sandal sole waste materials that
manages the environment, pyrolysis is the best way. It will indirectly help to manage such
non-biodegradable wastes, also low grade liquid fuels may be obtained. When waste
materials were pyrolyzed, they generate oil, char and gas, which are valuable. The oil has
sufficient calorific value and may be used to provide process energy and char may be used
as activated carbon or carbon black. So, they may be considered as a new raw material for
pyrolysis. In the present study, waste shoe/sandal soles were collected from the nearby local area of Jashore and Khulna city of Bangladesh were pyrolysed in a batch type
reactor.
Experiments on pyrolysis of shoe/sandal soles were conducted by varying the temperature
within the range of 200-250oC at every 25oC. The batch type fixed-bed pyrolysis system
was constructed and installed in the Heat Engine Laboratory of Department of Mechanical
Engineering, Khulna University of Engineering & Technology. The maximum yield of
pyrolytic oil and pyrolytic solid from waste shoe/sandal soles was 36.0 % (by weight) and
53.0 % (by weight) with the feed size of 0.75 × 0.50 cm and 1.25 × 1.0 cm respectively
with loading size of 1.7 kg.
The properties of pyrolytic oil obtained from waste soles of shoe/sandal such as density,
flash point, boiling point and pour point were measured and the respective values are in the
range of 0.877 – 0.934 g/cm3, 96 - 108oC, 153 – 158oC and -11 to -12.5oC respectively and
the gross calorific value (GCV) is around 35 - 38 MJ/kg. The gross calorific value (GCV)
of pyrolytic solid is around 11 - 16 MJ/kg which is comparable to same of peat (12 to 16
MJ/kg) and lignite coal (13 to 16 MJ/kg). The concentrations of elemental compositions of
pyrolytic liquid obtained from shoe/sandal sole pyrolysis were found to be almost 71.7%
for carbon, 10.9% for hydrogen, 1.12% for nitrogen, 0.50% for sulphur and 15.78% for
others at 200oC. The derived oil from pyrolysis of waste shoe/sandal soles were
investigated for FTIR four groups: alkane, alkenes, alkynes and aromatic compounds. The
results showed more aromatic hydrocarbons. The TGA analysis of the same shows that the
experimental curve is higher from 200 to 400ºC, when the rate of weight loss of
shoe/sandal sole pyrolysis is higher. The oil obtained from pyrolysis of shoe/sandal sole
wastes can be used as alternative fuel or chemical feedstock after some treatment. The
results show that these properties are similar to that of the low grade liquid fuels and thus
pyrolysis of such waste soles of shoe/sandal will reduce environmental pollution to some
extent as well as be an alternative source of energy.
This thesis is submitted to the Department of Energy Science and Engineering, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering in the Department of Energy Science and Engineering, June 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 89-96).
2019-06-01T00:00:00ZEffect of Various Operating Parameters on Power Generation from Mediator Less Microbial Fuel Cell
http://hdl.handle.net/20.500.12228/538
Effect of Various Operating Parameters on Power Generation from Mediator Less Microbial Fuel Cell
Halim, Md. Abdul
Microbial fuel cell (MFC) is the most adaptable renewable energy technology for its
multidimensional applications. This bioreactor converts the chemical energy stored in
decomposable organic and inorganic compound into electricity with the help of bacteria. The
whole process occurred in an air free environment. Significant amount of research works has
been carried out to improve the yield of MFC. In this research work, three MFCs were
constructed using locally available materials. Local window glass was used to construct the body
of MFC, Agar-agar solution and bandage cloth were used for salt bridge. Several experiments
were performed in batch mode to investigate the effects of various operating parameters such as
electrode material, electrolyte source, pH and concentration. To investigate the effect of
electrode materials, three anode materials (carbon felt, Zinc and carbon rod) were used and
copper was used as cathode with every cathode. Zinc-copper combinations gave 28.2% higher
power than carbon felt-copper and 57.1% than carbon rod-copper. For operating pH, pH 6, pH 8
and pH 10 were investigated, where maximum power generated from pH 8, its value was
680.625 mW. To investigate better electrolytic source municipal waste water, river water
(Bhairab) and hospital waste water was studied and maximum power (5.907mW) generated from
Bhairab river water. Additives affect the power generation of microbial fuel cell; urine mixed
waste water generates 52.13% and 9.6% higher power than raw waste water and fish waste
mixed waste water respectively. 10% urine mixed electrolyte gives maximum voltage (1146 mV)
but top power obtained from 15% urine mixed waste water. To get better yield source of
electrolyte (Bhairab river water), electrode combinations (Zinc-copper), operating pH (pH 8) and
15% urine as additive can be used.
This thesis is submitted to the Department of Energy Science and Engineering, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering in the Department of Energy Science and Engineering, May 2019.; Cataloged from PDF Version of Thesis.; Includes bibliographical references (pages 59-68).
2019-05-01T00:00:00Z