Harmless Food Additives and Cosmetics Are Destroying Million Dollar Turbines
After you enjoy that quick microwave meal or fix your makeup, what you throw in the trash could end up costing you in higher electric bills. First your waste makes it to the landfill. Then someone converts that into biogas to burn at a nearby electric power plant. During this process, siloxane gas found in landfill garbage damages the stainless steel turbine running the electric generators. Believe it or not, something as simple as food or cosmetics has the potential to destroy equipment worth millions of dollars.
While this may seem far-fetched, the engineers at Sorensen Systems are all too familiar with these problems. Power plant operators are struggling with contaminated biogas in some of our more innovative electric plants. In the face of rising costs for petroleum-based fossil fuels, such as coal, oil and gas, the idea of “cheap” biogas has gained popularity as an alternative.
Siloxane Contamination
So what exactly is happening here? Unlike natural gas, gases from landfills are saturated with moisture. They also carry varying quantities of compounds that contain sulfur, chlorine, and silicon. You can see siloxane in biogas in the form of a white powder in gas turbine hot section components. The white powder is primarily silicon dioxide, a product of siloxane combustion. This by-product has been identified as responsible for turbine failures, which has caught the attention of power plant operators. Fortunately, there are efficient and cost-effective ways to remove contaminants such as siloxane.
Siloxane removal systems are the best way for combustion turbine plant operators to reduce the consequences of siloxane contamination in the biogas fuel. The biogas generated in landfills and wastewater digesters contain siloxane – a man-made chemical that changes into silicon dioxide (sand) when combusted. Imagine throwing sand into your car engine! That’s what’s happening here.
Siloxane Removal Systems
When landfill and digester gas are used to fuel turbines, silicon dioxide builds up. This build-up significantly increases maintenance costs, reducing the feasibility of these important green energy projects. A siloxane removal system offers a way to reduce the harmful affects. One tower adsorbs siloxane using a specialized blended media and the other tower regenerates. This exhaustes the collected siloxane to a flare or thermal oxidizer. In combination with advanced chilling systems and improved filtration, power plant operators have reason to believe that a solution exists for combating siloxane contamination.