Study On The Treatment Of Wastewater From Orange Can Production

China is the country with the largest orange can production in the world. It is very difficult for the traditional bio-treatment to treat the practical wastewater because of the large amount of wastewater, high SS and difficult degradation of pectin. So it is important to carry on the study on the treatment of the wastewater from the orange can production. The result could be put into wide use to treat 9,000,000 tons of wastewater from the orange can processing in our country.In this paper, the cleaner production proposal was offered though the survey of enterprises of orange can production and analysis of the wastewater properties from the processing. The technology of acidification hydrolysis combined with the contacting oxidation was offered according the practice and the shortages of the present process. The suitable operational parameters were achieved by the tests. The efficiency of treatment was compared in different processes and conditions. The results shown that it is feasible to adopt the process of acidification hydrolysis combined with the contacting oxidation to treat the wastewater from the orange can processing. When the COD was less than 1000 mg/L, BOD₅ less than 486 mg/L and SS less than 250 mg/L in influent, the water quality in effluent could reach the comprehensive discharging standard of first rank (GB8978-1996) and the best HRT for the acidification hydrolysis was 8 hours and for the contacting oxidation was 10 hours. The suitable HRT could overcome the badly effect from the difficult bio-degradation of pectin. The kinetic model was U =98.25/(16.6+S) according to the data from the experiment.According to the results and engineering practice, a set of treating process was designed in terms of the idea of cleaner production and comprehensive utilization of waste materials, the direct operational cost is 1.16 yuan(RMB) for each ton of wastewater.