Presence of H2S in biogas must be removed before send it to cogeneration engines, in order to avoid corrosion problems.
Landfills and Digestors Biogas Desulphuration
The energetic valorization in cogeneration engines of biogas produced in landfills, waste water treatment plants and methanation processes, has brought the need for elimination of certain harmful compounds for such engines. Mainly:
- Cause degradation of the oils, shortening its meantime life with the consequent cost of maintenance
- Produces corrosion in the engine
- They are silicone derivatives which are subsequently decomposed into silica and silicates
- Cause abrasion on the heads of the valves and precipitates in the chamber
TECNIUM has developed diferent technologies that can be applied, based on criteria of:
- Limits required by engine manufacturers
- Accepted operating costs
- Services available in the plant
Based on the above parameters the different technologies are:
The biogas is treated in a bioscrubber, on a special inorganic packing, where a biofilm is generated that will cause the oxidation of H2S in the presence of oxygen and an adequate supply of nutrients.
Installations suitable for concentrations up to 4000ppm.
Involve high investment but low exploitation costs.
In cases where the presence of H2S is high, a chemical process of oxidation / reduction in countercurrent scrubbers is required.
Are applications for up 10.000ppm tipically on waste landfills with highly variable compositions depending on the area.
If the concentration is lower, alkaline chemical treatment may be sufficient.
The investment costs are low, but the exploitation is important due to reagent consumption and generation.
By using appropriate activated carbon medias, H2S removal is achieved at low concentrations.
Making a "mix" of carbons, siloxanes can also be removed. The saturation of carbon used, autonomy and subsequent regeneration, are determining factors when selecting this solution.
TECNIUM makes complete installations, even in classified areas ATEX, selecting the best technology.