The Study Of Recovery Methods Of Pollutants In Industry Wastewater As Ammonia-nitrogen, Acetic Acid And Correlative Problems

In this paper, it has been studied that recovery methods of pollutants in industry wastewater as ammonia-nitrogen, acetic acid and correlative problems.(1) The effects of processing conditions on NH₄⁺-N (ammonia-nitrogen) removal to form struvite (magnesium ammonium phosphate, MAP) were studied in a laboratory scale. MAP precipitation was carried out by adding phosphoric acid and MgO. The effect of pH was significant and the highest removal was obtained at pH 9. 0. A PO₄^3-: Mg²⁺ : NH₄⁺ molar ratio of 1 : 1. 5 : 1 was found to be beneficial for the higher removal of NH₄⁺-N and the higher recovery of ammonia to form struvite. In addition, the feed-in sequence of material significantly affects NH₄⁺-N removal. It was shown that a highest NH₄⁺-N removal of 99.1% and an ammonia recovery of 80.1% could be obtained by a two-step precipitation process.(2) The process of producing industrial pure acetic acid by extraction rectification after of furfural wastewater is investigated in this essay, and the author hopes to provide basic application in industry.(3) Electrochemical generation of active chlorine in diluted and concentrated NaCl solutions was investigated at Ti/PbO₂ anode. The active chlorine yielded by the electrolysis was significantly affected by the concentration of chloride ions, temperature, current density, pH, electrode material, diaphragm. The effects of above mentioned factors are comparatively different in diluted and concentrated NaCl solutions. It was found that the active chlorine produced in the solution was consistently higher at Ti/Ru-Ti-Sn oxide coated titanium anodes than that at Ti/PbO₂ anodes. The results may provide as much information as possible for the practical use of electrochemical treatment of industry wastewaters.(4) Under the atmospheric pressure, by taking palmitic acid, ethylene diamine, and chloro-acetic acid as the main raw materials, a kind of carbonic acid anionic gemini surfactant was synthesized. Its structure was identified by spectral means, and its surface activity was measured in the water. The result shows that its surface activity was higher than that of the ordinary surfactant. This synthetic method is easy for the industrial production.