The main pollutants in fertilizer plant wastewater are: cyanide, sulfide, ammonia nitrogen and other toxic and harmful substances, which have great environmental pollution.
So how to deal with the fertilizer plant ammonia nitrogen wastewater? When dealing with this type of wastewater, the choice of wastewater treatment process has a variety of, including: biochemical, flocculation precipitation, adsorption, ion exchange, ozone oxidation, membrane separation technology , The actual application, are a variety of processing methods cooperate with each other in order to achieve the best processing results, while saving the maximum processing costs.
First, the source of fertilizer plant ammonia nitrogen wastewater
Ammonia nitrogen fertilizer plant fertilizer mainly from ammonia, urea plant ammonia concentration of high concentrations of waste water, ammonia nitrogen in this part of the main form of inorganic ammonia. The quality of wastewater from fertilizer plants has the characteristics of high ammonia nitrogen content and toxic total cyanide and sulfide. And the biodegradability of such sewage is poor (mainly low chemical oxygen demand and high ammonia content).
Second, fertilizer plant ammonia nitrogen hazards
Ammonia-nitrogen, the main pollutant in the fertilizer plant effluent, is an important pollutant that causes eutrophication and environmental pollution. Currently, ammonia-nitrogen is one of the major pollutants in almost all contaminated waters in China.
1. Water body eutrophication has endangered agriculture, fisheries, tourism;
2. pose a tremendous threat to drinking water sanitation and food safety.
Water pollution, especially water eutrophication, has become an important factor in China's economic development. Fertilizer industry wastewater often contain high concentrations of ammonia nitrogen, ammonia is one of the main sources of wastewater. Therefore, how to remove ammonia nitrogen from fertilizer industrial wastewater has become an important issue in wastewater treatment.
Third, fertilizer plant ammonia nitrogen wastewater treatment
Ammonia nitrogen fertilizer plant wastewater treatment, no matter what kind of technology and methods used, the general process can be divided into three steps.
The first step: pretreatment. The wastewater from the fertilizer plant can be preliminarily purified by such methods as grid filtration, water quality and water quantity adjustment, chemical precipitation, floating, grease isolation and the like. The purpose is to separate suspended solids, colloids, oil slicks, heavy oils and other impurities in the water. After pretreatment, large particles of suspended solids in the wastewater, oil and other substances basically clean.
The second step: biological purification. Biological treatment of fertilizer plant ammonia nitrogen wastewater purification is the use of microbial degradation, the wastewater can be dissolved in organic matter and colloidal substances biodegradable, can effectively reduce the water content of ammonia nitrogen and COD and other content. The wastewater quality after the biochemical treatment can basically reach the standard discharge. The sludge at the bottom of the reaction tank can be added to the Xi-Jie ammonia-removing agent. If the water quality is rather complicated and COD, chroma and other indicators are not up to standard, deep purification is needed.
The third step: deep purification. Mostly used activated carbon adsorption, ozone oxidation, ion exchange, membrane separation and other technologies, the purpose is to reduce the COD content of wastewater and color, adsorption of water smell, odor, and some difficult to degrade organic matter Pollutants and dissolved inorganic pollutants, the water purification standards.
Tips
requires attention
(1) Since the wastewater quality, quantity of water and treatment standards vary from fertilizer plant to plant, there are also significant differences in treatment options.
(2) In the entire fertilizer plant wastewater treatment process, the ammonia nitrogen wastewater treatment agent used is Xi Jie ammonia nitrogen removal agent.
(3) Among them, the flocculation sedimentation process, the use of more Xi Jie ammonia nitrogen removal agent; and sludge dewatering should be based on water quality selection.