Analytical approach for predicting biogas generation in a municipal solid waste anaerobic digester

There is an increasing worldwide interest in the effective utilisation of municipal solid wastes as an avenue of reducing its high cost of clearing. Municipal solid wastes are usefully converted into a medium grade fuel [biogas] to reduce its nuisance value to the environment. In this paper, the potential of vegetable [putriscible] component of municipal solid wastes was examined in terms of biogas production. The vegetable component of the waste was used as substrate in a batch-fed 200 dm[3] capacity anaerobic digester, which was consecutively loaded with a 10-20 kg ranged weight of vegetable. The total solid [TS] of substrate was 8-10% over a retention period of 40 days. The temperature of the substrate during bio-digestion was maintained within 29°C and 33°C. The average biogas yield varied from 5.15 dm[3]/kgTS to 5.83 dm[3]/kgTS. From the digestion experiments, a regression equation, called the municipal solid wastes energy value model, was derived. This model estimates the biogas production from municipal solid wastes. For the predictive model formulation, a relationship between retention time and the daily/total biogas yield was explored. The polynomial function significantly represents the models formulated for the different quantity of substrate loaded. This strongly suggests that the polynomial series is best suited to predict the relationship between retention time and the quantity of substrate loaded for the experiment. This tool is useful in optimising biogas production from energy materials, and requires further validation and refinement. Hopefully, this study advances this increasingly growing area of municipal solid wastes research

Utilization of poultry, cow and kitchen wastes for biogas production: a comparative analysis

The amount of solid wastes generated in developing countries such as Nigeria has steadily increased over the last two decades as a result of population explosion and continuous growth of industries and agricultural practices. In agriculture, particularly cattle rearing, large quantities of cow wastes are generated, which could be used as biogas inputs to compliment the fuel usage alternative. In addition, a large number of families generate heavy wastes in the kitchen on a daily basis, which could be converted to economic benefits. In this work, a comparative study of biogas production from poultry droppings, cattle dung, and kitchen wastes was conducted under the same operating conditions. 3kg of each waste was mixed with 9L of water and loaded into the three waste reactors. Biogas production was measured for a period of 40 days and at an average temperature of 30.5°C. Biogas production started on the 7[th] day, and attained maximum value on the 14[th] days for reactor 1. Production reached its peak on the 14[th] day with 85xl0[-3] dm[3] of gas produced in reactor 2. For reactor 3, biogas production started on the 8[th] day and production reached a peak value on the 14[th] day. The average biogas production from poultry droppings, cow dung and kitchen waste was 0.0318dm[3]/day, 0.0230dm[3]/day and 0.0143dm[3]/day, respectively. It is concluded that the wastes can be managed through conversion into biogas, which is a source of income generation for the society

factorial analysis experimentation of inappropriate waste disposal

This paper presents a statistical approach to estimating the effects of psychological factors on humans due to inappropriate waste disposal in the environment. Factorial experimental analysis is combined with the concepts of transition matrix and steady state conditions. An adequate understanding into the statistical quantification of the waste disposal concept would aid policy makers in effective decision making and the proper control of environment. The feasibility of developing statistical parameters for assessing the waste disposal concept is confirmed. The work shows the novelty of the approach