Gas Treatment Systems / Energy Recovery
After LFG has been collected, and before it can be used in a conversion process, it must be treated to remove any condensate that is not captured in knockout tanks, as well as particulates and other impurities. Treatment requirements will vary depending on end use application. Minimal treatment is required for direct use of gas in boilers or internal combustion engine, while extensive treatment is necessary to remove CO2 for injection into a natural gas pipeline. Power production applications typically include a series of filters to remove impurities that could damage engine components and reduce system efficiency. The cost of gas treatment depends on the gas purity requirements of the end user's application. The cost to filter the gas and remove condensate for power production is considerably less than the cost to remove carbon dioxide and other constituents for injection into a natural gas pipeline or for conversion to vehicle fuel.
The goal of a LFG-to-energy project such as those operated by BES is to convert LFG into a useful energy form such as electricity, steam, boiler fuel, vehicle fuel or pipeline quality gas. This is done by way of several technologies to maximize the value of LFG the most prevalent of which are:
- Power production/cogeneration
- Direct medium Btu gas use
- Sale of upgraded pipeline quality natural gas
Attempts to convert LFG into Liquefied Natural Gas ("LNG") have been successful from an engineering perspective however have yet to be proven economical.