Study of the Role of Enzyme in Reduction of Ammonia and Hydrogen Sulphide Gases from Biodegradable Municipal Solid Waste.

Population growth and rapid industrialization has increased the quantities of solid waste and one of the solutions for their disposal is dumping the waste in landfills. The landfill sites and transfer stations are major sources of harmful odour in its vicinity. Most common odour producing compounds are hydrogen sulphide gas and ammonia gas which is generated near transfer stations, landfill sites or dumping grounds. Skin, eye and nose irritation, allergies, psychological disorders, headache, fatigue, and gastrointestinal problems are some of the health problems caused by inhalation of this harmful odour. Several techniques are adopted to reduce the odor nuisance from the landfill site such as application of compost bio-filter, addition of nitrates, and better design of landfills. At some solid waste disposal sites enzyme technology has been used and has been proved effective which is based on suppression of anaerobic decomposition of solid waste. In the present study the effectiveness of enzyme-based technology was studied. An effort was made to reduce the odour nuisance caused by anaerobic decomposition of municipal solid waste at transfer stations by applying solution of enzyme of varying strength. The reduction in concentrations of the ammonia and hydrogen sulphide gas was measured in the ambient environment at specified locations by Multi Gas Detector. Different concentrations of enzyme solution were sprayed on the municipal solid waste. It was found that the ammonia and hydrogen sulphide gas produced by anaerobic decomposition of biodegradable organic matter reduced significantly. Results indicate that the application of enzyme technology efficiently suppressed the development of anaerobic condition in the municipal solid waste stored at dumping sites or at transfer stations. Hence this technology can be used at large scale to reduce the odor problem due to storage of biodegradable municipal solid waste.