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With the development of national economy, catering, tourism and other tertiary industries are also a number of rapid development, economic prosperity but also a large number of emissions of pollutants to the urban environment had a serious impact. Catering main factors of external environment pollution is the noise, dust and waste, including waste water in the proportion of urban wastewater in every year. Catering waste containing organic compounds, chemical detergents, suspended solids, oil and other pollutants, their impact on the water environment causing serious pollution. In this experiment, from the business of cafeteria food waste, grease content of 7600 mg / L or so, total suspended particles in the 5000mg / L or so, pH value between 6-7, CODcr of 1000-3000mg / L, SS 500 - 1500mg / L. Such is the main pollutant effluent oil, suspended solids and dissolved organic pollutants. Wastewater treatment at home and abroad such methods are activated sludge, membrane bioreactor, coagulation, ceramic film processing, electro-coagulation flotation, electrolysis - electrolysis method, etc., there are many successful examples, but most exist complex process, treatment is not thorough, high operating costs, management requirements and covers an area of ??disadvantages such as high. This article has been including chemical pre-oxidation, organic polymer-enhanced coagulation as the main content of intensive study routine tests. Pre-oxidation processes are oxidants, pH, time of pre-oxidation. Oxidation test results showed that: pre-oxidation 40 minutes, potassium permanganate dosage 6ml / L, CODcr treatment rate reached 37.6%, compared with sodium hypochlorite solution is used as an oxidizing agent, only less dosage, and CODcr removal. Coagulation process by coagulant type, coagulant dosage, coagulant dosage, pH, velocity gradient and precipitation time effects, the test results show that: for the restaurant sewage, select polyacrylamide (PAM) As the organic polymer coagulant enhanced coagulation better. Using a single chemical oxidation or coagulation treatment of the sewage can not be achieved when good treatment effect, and first with a solution of potassium permanganate oxidation, and then combined with PFS and polyacrylamide coagulation treatment for with good results, the treated effluent CODcr in 200mg / L or less. With a potassium permanganate solution as oxidizing agent water, the amount of potassium permanganate, 6.0ml / L, the reaction time was 40 minutes, and then combined with ferric sulfate and polyacrylamide water sample after oxidation treatment, PFS amount of 200mg / L, PAM dosage of 2.0mg / L, 170r/min (G = 395 S -1 ) was stirred rapidly 20s (GT = 0.59 × 10 4 ), and then to 50r/min (G = 160S -1 ) mixing 7min (GT = 6.72 × 10 4 ), settling at 20 min, CODcr removal rate up to 86% of the total .
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