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CO-COMPOSTING OF OLIVE MILL SOLID WASTE AND CHICKEN MANURE
Bassim Eid Abbassi, Ph.D. ABSTRACT
The massive amount of solid residues from the agroindustries causes serious
environmental problems due to their high organic content. Chicken manure and olive mill solid residues (pomace) are usually applied in
agriculture or disposed of without any further treatment causing serious environmental problems especially in hot weather. Co-composting
of these solid residues has been studied as a new innovative method. Composting was carried out at different C/N ratios ranging from 20
to 35 and started by addition of water to reach a moisture content of 60%. A brief thermophilic period was observed 3 days after
starting composting with a maximum developed temperature at the centre of the material of 65 ºC. Subsequently, the temperature maxima
declined and did not exceed 35 ºC after the first four weeks of composting. The experiments showed clearly that the optimum C/N ratio of
the composting material was between 25 and 30. This conclusion was also based on the proposed weighing indicator equation for composting
maturation.
CONTAMINATION OF SOLID WASTE FROM TOXIC MATERIALS IN ELECTRONIC WASTE (E-WASTE)
Sunil Herat, Ph.D. ABSTRACT
Electronic waste or e-waste is the fastest growing and the latest waste stream in global
waste sector. Ever increasing demand for electrical and electronic equipment (EEE) such as computers, mobile phones, televisions,
washing machines, refrigerators in our modern society coupled with wide availability of latest designs in the electronics industry lead
to rapid obsolescence of EEE well before their end-of-life use. Apart from the significant number of EEEs entering the global stream,
the toxicity of certain materials contained in them is major concern to waste managers. E-waste contains more than 1000 different
substances out of elements such as lead, mercury, cadmium, hexavalent chromium and brominated flame retardants are of major threat to
human health and the environment. Regulations are being developed or implemented in many countries around the world to ban or restrict
above materials from EEE. This paper investigates the use and toxicity of materials used in the manufacture of EEE that could
contaminate the solid waste streams.
MANAGING E-WASTE—A REUSE STRATEGY FOR UK COMPUTERS TO FACILITATE DEVELOPMENTS IN THIRD SECTOR
ORGANIZATION COMPOSTING IN CAMEROON
Margaret Bates, Lawrence O. Mbeng, Paul S. Phillips ABSTRACT
While there has been much debate in the past as to the banning of e-waste being exported
to Africa, the new paradigm today is with the reuse of this e-waste to enhance Africa’s economic and social development. This paper
highlights some of the setbacks underpinning the importation of e-waste into Africa from existing legislation, which has incessantly
widened the gap between the haves and have-nots of information technology. Based on these, the paper presents a snapshot of a 5 year
pilot project for the reuse of second computers from the UK to Cameroon with the aim of driving sustainable practices in the composting
of household organic waste and hence create new markets in Limbe and Douala -Cameroon through education and capacity building.
STUDY OF SOME PERFORMANCE PARAMETERS OF AN ATMOSPHERIC BUBBLING FLUIDIZED BED BOILER BASED ON COAL WASHERY REJECTS CONSIDERING BUBBLE GROWTH ALONG BED HEIGHT
S. K. Mohapatra
Ravi Inder Singh ABSTRACT
The increasing problem of the disposal of solid wastes has presented many cities with a
dilemma while choosing suitable disposal methods. The traditional means of disposal of solid wastes like coal washery rejects and
middling, municipality waste, rice husk, saw dust etc. have been open dumping, land filling or dumping in the sea. These practices have
been discouraged due to non availability of land and new environmental legislation. Incineration, has, therefore been identified in
several studies to play an important role in future as disposal for solid waste. In India, fluidized bed combustion technology is
gradually emerging as a potential technology for the incineration of solid wastes like washery rejects and middling, rice husk, saw
dust, and municipality wastes etc. A number of small scale fluidized bed combustion power plants have been commissioned in the recent
past as a result a large amount of data is available for modeling and simulation. A mathematical model has been developed for the
exit-gas composition in a 10 MW atmospheric fluidized bed boiler in which coal washery rejects are being incinerated at Jamadoba, India.
The model allows for bubble size variation with height and predicts the composition of outlet gas composition. Model predictions are
compared with plant data and reasonable agreement is obtained.
FUZZY LOGIC MODELING OF BIODEGRADATION OF MUNICIPAL SOLID WASTE UNDER AEROBIC AND ANAEROBIC SIMULATED BIOREACTORS LANDFILL
Septa Rendra and Leta Fernandes
Mostafa A. Warith ABSTRACT
A fuzzy logic model was developed to simulate biodegradation of municipal solid waste
(MSW) in simulated bioreactors landfill under aerobic and anaerobic conditions. The bioreactors were operated to determine the amount of
leachate recirculation and municipal wastewater sludge addition required to optimize waste biodegradation. The leachate generated was
recycled over 47 and 63 weeks, leachate samples were collected on a weekly basis and analyzed for chemical oxygen demand (COD). The
temperature of the MSW in the bioreactors was measured on a daily basis. Leachate and sludge were added at the rates of 5 L/wk to 15
L/wk and 0.5 L/wk to 1.5 L/wk, respectively. Within 27 and 41 weeks for aerobic and anaerobic bioreactors, enhanced MSW degradation was
observed at a leachate recirculation rate of 15 L/wk (855 mL/kg of MSW/d) and sludge addition rate of 1.5 L/wk (85 mL/kg of MSW/d).
During this period, the COD concentration in the leachate dropped from 38,000 and 45,000 mg/L to approximately 1000 mg/L for aerobic and
anaerobic bioreactors, respectively. Reduction in the leachate recirculation and sludge addition rate to 285 and 28 mL/kg of MWS/d
respectively, increased the waste stabilization period up to 45 and 63 weeks for aerobic and anaerobic bioreactors. Within 10 and 25
weeks in aerobic and anaerobic bioreactors, temperatures reached the peak at 56 and 38 0C at a leachate recirculation rate of 855 mL/kg
of MSW/d and sludge addition rate of 85.5 mL/kg of MSW/d). Based on the two parameters, COD and temperatures, fuzzy logic approach was
employed to develop a MSW biodegradation model. The results obtained from the fuzzy logic simulation demonstrated reasonable agreement
with the experimental observations. Although there were deviations between the model simulation and measured data, the simulation
results can closely predict the trend of the MSW biodegradation process. The overall evaluation of the simulation also confirmed the
efficiency and reliability of the model to reproduce pertinent characteristics and important features of MSW biodegradation under
leachate recirculation and sludge addition with or without air addition. Accordingly the MSW biodegradation process can be accurately
simulated using the fuzzy logic control approach.
USE OF PRECIPITATION DATA TO DEVELOP AND MODIFY THE LEACHATE MODEL FROM SMALL-SCALE LANDFILL OF MSW COMBINED WITH INCINERATION ASHES
Jing-Dong Chow
Wan-Lan Chai ABSTRACT
The principal purpose of this study is to explore the influences that adsorption,
desorption, and biological reactions may have on leachate quality from landfill. The disposal site of MSW combined with incineration
ashes is simulated by two outdoor pilot-scale lysimeters, assuming that an incinerator had treated 60% and 90% of MSW respectively. The
incineration ashes would be disposed with MSW surplus. The characteristics of incineration ashes disposal can be determined by comparing
the experimental results. Since these parameters were obtained in a laboratory rather than under actual conditions, the relationship
between these parameters and precipitation should be considered. These parameters must be modified by natural conditions such as
precipitation in order to obtain the characteristics under actual environment. Based on the model established by the authors
(2000,2001)[1,2], the modification and exact model of leachate from the landfill of MSW combined with incineration ashes is thus
established. The leachate quality is approximately similar to the experimental data and the simulation results.
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