Industry & Resource Management Goal 2: Reduce methane emissions from landfills
IR-2.1: Install, expand and maintain landfill gas collection systems
Landfill gas is the by-product of the decomposition of solid waste in landfills and is comprised primarily of carbon dioxide and methane. Most GHG emissions from landfills occur from landfill gas that escapes to the atmosphere through uncapped areas of the landfill.
Instead of allowing landfill gas to escape into the air, the gas can be captured, converted and used as an energy resource.
The primary action for reducing GHG emissions at landfills is to expand and improve methane collection systems. Landfill gas collection systems are typically installed in phases as landfill operations progress and areas become filled with waste. Ongoing landfill operations constrain installation of collection systems and do not allow for complete collection of gas until after the landfill is closed and capped.
All of the region’s open landfills and most of its closed landfills have methane recovery systems in place. Once captured, the methane is either destroyed through flaring or it is beneficially reused as an energy source.
IR-2.2: Beneficially reuse landfill gas
Once captured, methane-containing landfill gas (a medium-Btu gas) is either destroyed through flaring or it is beneficially reused as an energy source. The destruction option chosen by a landfill is ultimately dependent on quantity and quality of landfill gas.
Landfill gas can be used directly to offset the use of another fuel (for example, natural gas, coal or fuel oil) in a boiler, dryer, kiln, greenhouse or other thermal application. In these projects, the gas is piped directly to a nearby customer for use in combustion equipment. The Courtney Ridge Landfill pipes landfill gas directly to a cement kiln as an offset for traditional fuel.
Landfill gas also can be converted to electricity by using reciprocating internal combustion engines, turbines, microturbines and fuel cells. The Central Missouri Landfill, located in Sedalia, uses reciprocating engines to generate electricity.
Landfill gas can also be upgraded to a high-Btu gas through treatment processes that increase its methane content. The Johnson County Landfill converts landfill gas to high-Btu gas by reducing its carbon dioxide, nitrogen and oxygen content. After conversion, the high-Btu gas is injected into a natural gas pipeline.