Electroflox® Pilot plant for primary wastewater treatment of leachate

N. Marriaga-Cabrales, F. Machuca-Martinez, D. Donneys-Victoria, C.E. Alvarez-Pugliese

Keywords: metal electrodissolution, flocculation, treatment for industrial wastewater


Landfill leachates are liquid effluents that contain a high pollutant load and represent a serious environmental challenge for the disposal sites; Even after the useful life of a landfill, leachates continue to be generated for decades. Different alternatives have been used to mitigate the environmental impact of this effluent, including biological, physicochemical and physical treatments. However, it has been found that many of the alternatives have deficiencies to reduce the content of recalcitrant pollutants, such as ammonium, or fail to reach the legal parameters in such as Chemical Oxigen Demand (COD) and Biological Oxygen Demand (BOD) that allow the discharge of the effluents into the bodies of water; They also have high operation costs and require large land extensions. The Electroflox® process consisting of a stage of metal electrodissolution and a subsequent flocculation step has been developed at the Universidad del Valle since 2007 as a primary treatment for industrial wastewater, and it has been patented in Colombia, Mexico and the United States. In 2016, it was possible to scale up the process with the design, construction and set up of a mobile pilot plant with capacity to treat up to 1200 liters / hour. The plant is installed at a sanitary landfill operated by VEOLIA® in the South West of Colombia, and is coupled with a reverse osmosis system. Preliminary results are promising, as after the Electroflox process the flux in the reverse osmosis system increases up to 133% with a reduction of up to 66.8% in the COD. The recent application of the pretreatment at a pilot scale brings this technology to the market and bring closer the technological maturity, with several companies interested in testing the technology.