composed when organic waste in landfills is covered and compressed by heavy equipment. There are four stages of decomposition:
The methane gas created by the anaerobic process in a waste landfill must be vented to prevent explosions. This gas is usually flared off to be safely disposed of.
Areas are carefully prepared for new landfills with a base of clay, sand, and membrane designed to prevent leachate from reaching the groundwater. A layer of garbage is added, compacted mechanically, and topped with a layer of soil.
Another layer of garbage and more soil is added, and so on until the landfill section is deemed full. The area is then topped with special low permeability soil, an HDPE membrane, more soil, and vegetation cover. Holes are bored and piping collects the potentially hazardous methane gas. The quantity of vent pipes is determined based on many factors including the rate of decomposition, climate, thickness, the number of layers, and more. A multistage centrifugal blower/exhauster forces the gas mixture, mostly methane gas and carbon dioxide, to leave the landfill and send it to the landfill gas vent flare.
This process can use one or multiple multistage centrifugal blowers/exhausters. A single blower/exhauster could draw from twenty or fifty vent pipes; however, the vent pipes must be engineered to draw an even vacuum. Multiple blowers/exhausters can address this potential issue.
The methane gas created by the anaerobic process in a waste landfill must be vented to prevent explosions. This gas can be valuable and is often saved.
If economically feasible, the gas is cleaned to pipeline quality as “renewable natural gas” or “biomethane”. The gas can be added to the gas pipeline grid and mixed with natural gas. Additionally, the biomethane gas can be used to heat water or air or heat part of an industrial process. If compressed, biomethane can power internal combustion or fuel cell vehicles.
After the landfill gas blower/exhauster passes the methane and carbon dioxide mixture, it is diverted to a second blower/exhauster, which goes to hydrogen sulfide removal, a dyer and scrubber tower, or to clean the gas. At this time, food-grade CO2 can be separated from the methane. Siloxane trace contaminants are also removed and hinders combustion. An aftercooler may be required to cool the volatile methane gas after compression. The cleaned methane gas moves to a storage vessel where it can be used in the process or added to the natural gas grid.
Equipment is tested before reaching the customer or end-user. Thus, ensuring top quality and avoiding operational downtime. Therefore, upholding Hoffman & Lamson’s strong reputation as the global leader of engineered solutions and producing premier quality products efficiently and economically. There are over 100,000 HOFFMAN & LAMSON multistage centrifugal blowers/exhausters in operation worldwide.