Study On Treatment Of Wastewater Reuse Using The Biological Aerated Filter

Water reuse is a first choice to settle the problem existing in the word which is the shortrage of water resource.The biological aerated filter(BAF) has great donminaces in the water reuse,especially suitable for the existing condition in our water treatment.In this subject,the advanced treatment of the effluent of Gao Beidian wastewater treatment plants using one-stage aerobic BAF and anoxic-aerobic two-stage BAF was studied.The height of media,the ratio of gas to liquid,hydraulic loading,the organic and ammonia loading of influent are the key factors influence the performance of one-stage aerobic BAF.The conclusions of the experiment are as following:the best height to remove the organic matter and ammonia is at 60cm,120cm from the influent side respectively.The best ratio of gas to liquid is 3:1～4:1;The organic and ammonia loading of influent have litlle influence on the performance of one-stage aerobic BAF when the concentration are low; Whe the ratio of gas to liquid is 3:1,the ammonia loading is blow 0.87kgNH₄⁺-N/m³.d,the enfluent concentration of ammonia is blow 5mg/L which satisfies the water reuse standard;At different organic loadings,the removal of organic matter keeps 35%～45%.Hypothermia is unfavourable to nitrification for one-stage aerobic BAF to removel ammonia, the influent concentration of ammonia can't satisfy the water reuse standard. Putting the potassium permanganate into the filter can improve its effect ,the removal of organics and ammonia is increased, the influent concentration can satisfy the water reuse standard.But the turbidity of influent is unsatisfactory.The C/N ratio is the key factor to influence the nitrogen-removal of the anoxic/aerobic two-stage BAF when the reflux ratio,hydraulic loading and the ratio of gas to liquid in aerobic filter are fixed. The anoxic/aerobic two-stage BAF has a good removal of organics at different C/N ratio when the reflux ratio is 2, hydraulic loading is 2.55m³/m²Â·h and the ratio of gas to liquid in aerobic filter is 3:1.The influent concentration of organics is blow 7mg/L.From the beginning to 30cm of the anoxic filter ,the removal of the organics is significant;As the C/N ratio increasing ,the influent concentration of ammonia is decreasing.When the C/N ratio is 3.60,the enfluent concentration of ammonia is 3.05mg/L which satisfies the water reuse standard.When the C/N ration is less than 3.60,because of the imperfection...