Lixiviates of such plants are usually polluted with organic or inorganic compounds such as NH3, CO2 or VOC's. These waters must be stripped before disposing them.
It is often necessary in the treatment of any liquid effluent, remove certain compounds that can interfere with subsequent processing.
In general the removal of NH3, CO2 or Volatile Organic Compounds (VOC's) can be performed by different methods.
One of them consists in the stripping, in which the volatile component is separated from the liquid effluent, through the action of an inductor element which can be air, steam, nitrogen, etc..
The process is done in countercurrent scrubbers, where is essential to achieve an optimal relation liquid/gas, as well as a packing with very high specific surface but that simultaneously prevents its flood.
The simplicity of the stripping process regarding installation and operating costs, makes it suitable for many applications.
TECNIUM accounts with numerous references for this type of treatment.
Removal of NH3
It is common to find the presence of ammonia in lixiviates from landfills and MBT plants, after evaporation processes where it is necessary to remove ammonia, before chemical-physical treatment.
Similarly, we may find the need to remove ammonia in effluents from the fertilizer or glass industry.
Another area of application is the treatment of lixiviates from manure treatment plants.
After removal of the ammonia, if the concentration in the air / vapor is high, it may require a further acidic absorption step (sulfuric acid, phosphoric, ...).
Sometimes when using a reverse osmosis water and we need to correct the pH, we can eliminate the CO2 present in this water, using an air stripping process.
It is normal to find water with 100ppm of CO2 and achieve efficiencies of 99% removal.
Our algorithms allow us to optimize the relacción L/G with high performance packings.
Removal of VOC's
Stripping technology can not be generalized for all volatile organic compounds present in a possible effluent.
From the study of their chemical nature, vapor pressure, etc., can be decided whether this technology is applicable.
We have applications and references removing aliphatic chains chlorinated compounds such as trichlorethylene, trichloroethane, etc.
Although this application is described in the treatment of biogas, we highlight this application when the biogas is enriched with methane removing the CO2 and H2S by compression at 9/10bar.
Lixiviate produce has a high concentration on H2S which is removed by stripping, to be subsequently deodorized.