WASTE TYPES MUNICIPAL SOLID WASTE
Landfill gas production results from chemical reaction and microbes acting upon the waste as the putrescible material begins to break down in the landfill. The rate of production is affected by waste composition and landfill geometry, which in turn influence the microbial populations within it , chemical make-up of waste, thermal range of physical conditions, and the biological ecosystems co-existing simultaneously within most sites.
Landfill gas is the natural by-product of the decomposition of solid waste in landfills and is comprised primarily of carbon dioxideand methane, which is then combusted to generate electricity .
Landfill gas is composed of a mixture of hundreds of different gases. By volume, landfill gas typically contains 45% to 60%Methane and 40% to 60% carbon dioxide. Landfill gas also includes small amounts of nitrogen, oxygen, ammonia, sulfides, hydrogen, carbon monoxide, and nonmethane organic compounds (NMOCs) such as trichloroethylene, benzene, and vinyl chloride.
Methane is a primary constituent of landfill gas (LFG) and a potent greenhouse gas when released to the atmosphere. Reducing emissions by capturing LFG and using it as an energy source can yield substantial energy, economic, and environmental benefits. The implementation of landfill gas energy projects reduces greenhouse gas emission and air pollutants, leading to improved air quality and reduced possible health risks. LFG projects also improve energy independence, produce cost savings, create jobs, and help local economies. Internationally, significant opportunities exist for expanding landfill gas energy.
LFG is extracted from landfills using a series of wells and a vacuum
system,and collected the gases through pipes. Once the landfill gas is
processed, it can be combined with natural gas to fuel conventional combustion
turbines.Instead of allowing LFG to escape into the air, it can be
captured, converted, and used as an energy source. Using LFGE helps to reduce
odors and other hazards associated with LFG emissions, and it helps prevent
methane from migrating into the atmosphere and contributing to local smog and
global climate change. LFG is extracted from landfills using a series of wells
and a blower/flare
(or vacuum) system. This system directs the collected gas to a central point
where it can be processed and treated depending upon the ultimate use for the
gas. From this point, the gas can be simply flared or used to generate
electricity, replace fossil fuels in industrial and manufacturing operations,
fuel greenhouse operations, or be upgraded to pipeline quality gas.
Links for Reports and Research Paper
ENERGY RECOVERY FROM LANDFILL GAS IN DENMARK AND WORLDWIDE
Estimates of Methane Recovery in Landfill Gas Flaring and Utilisation
LANDFILL GAS RECOVERY IN SOUTH AFRICA_ STATUS ISSUES AND MARKETS
Economic evaluation of a landfill system with gas recovery for municipal solid waste management a