What are the most effective ways to capture and use landfill gas?

1 LFG capture systems

To capture LFG, a network of wells, pipes, and blowers is installed in the landfill. The wells are drilled into the waste layer and connected to a header pipe that collects the gas. The blowers create a vacuum that pulls the gas out of the landfill and sends it to a treatment plant. The treatment plant removes water, dust, and other impurities from the gas and prepares it for use or flaring. Flaring is the process of burning LFG to reduce its environmental impact when there is no end use available.

2 LFG electricity generation

One of the most common and effective ways to use LFG is to convert it into electricity. This can be done by using internal combustion engines, gas turbines, microturbines, or fuel cells. These devices burn LFG to produce mechanical or electrical power that can be fed into the grid or used on-site. LFG electricity generation can reduce the dependence on fossil fuels, lower energy costs, and provide a reliable and flexible source of power.

3 LFG direct use

Another way to use LFG is to deliver it directly to end users, such as industries, buildings, or vehicles. This requires compressing and purifying LFG to meet the quality standards of natural gas or propane. LFG can then be used as a substitute or supplement for these fuels in boilers, furnaces, dryers, kilns, greenhouses, or vehicles. LFG direct use can reduce fuel consumption, lower emissions, and diversify the energy supply.

4 LFG conversion to biogas

A more advanced way to use LFG is to convert it into biogas, which is a high-quality gas that can be injected into the natural gas pipeline or used as a vehicle fuel. This requires upgrading LFG by removing carbon dioxide, hydrogen sulfide, and other contaminants and increasing the methane content. LFG conversion to biogas can be done by using various technologies, such as pressure swing adsorption, membrane separation, water scrubbing, or chemical absorption. LFG conversion to biogas can increase the value and marketability of LFG and reduce the need for flaring.

6 LFG benefits and challenges

Capturing and using LFG can provide multiple benefits for the environment, the economy, and the society, including reducing methane emissions, improving local air quality, creating jobs and income for landfill owners and operators, saving money and energy for end users and the grid, and enhancing public health and safety. However, there are also some challenges and barriers that need to be overcome to make LFG recovery more widespread and effective. These include high upfront capital costs, technical and operational issues, regulatory and policy uncertainties, as well as market and social factors. To address these challenges, various stakeholders must work together to create a supportive environment for LFG recovery and use.