Views: 15 Author: Site Editor Publish Time: 2018-06-20 Origin: Site
The effluent from the paper making process is treated by one level physicochemical treatment. Because the fluidized bed formed by flocculated sediment has the function of activated carbon, it contains a lot of suspended matter, COD, BOD and other organic pollutants than air floatation or submerged water. ZJDH high-efficiency sewage purifier is a kind of flocculant sediment which is produced by the paper-making sewage mixed with flocculant. It forms a stable, continuous and automatic renewable adsorption and filtration fluidized bed in the purifier. The physical and chemical treatment process of the deposit improves the removal rate by 10-20%. The processing capacity of a single device is 2500m3/d. After more than three years of operation, the results show that the removal rate of COD, BOD and SS can reach 92.5%, 78.5% and 98.9% respectively.
Papermaking wastewater has large volume, high concentration and poor biodegradability. The traditional biochemical treatment of this kind of papermaking wastewater has the advantages of large investment, high running cost and low removal rate. Recent years have shown that physicochemical method is more economical and practical. In some countries, the emphasis of treatment technology has been shifted to the research and development of physicochemical coagulation method. ZJDH high-efficiency sewage purifier is a kind of equipment system with only one stage physicochemical treatment process. It can treat the sewage from paper making with waste paper regenerated paddle material, and the removal rate of COD is above 90%; BOD is below 70%; SS is above 95%; the treated sewage can be reused to production.
1. Experimental research
1.1 principle of equipment
Papermaking wastewater by flocculation reaction can isolate a large number of sludge, activated carbon has similar good adsorption ability of these fiber containing flocculent mud, sedimentation or flotation process in the past, only the solids separation, not only give full play to the role of the filtration of sludge. Then the ZJDH high-efficiency sewage purifier is to use the flocculated sediment generated by these flocculation reactions to form a stable, continuously and automatically renewable fluidized bed attached only to the governor of Hong Kong, so that the pollutants play the role of activated carbon, so that the sewage into addition to the usual coagulation reaction after the solid-liquid separation effect, but also If the sewage is filtered and adsorbed, the removal rate can be increased by 10-20% compared with the conventional flotation or sedimentation process. Because ZJDH high-efficiency sewage purifier does not use any filter material or filler as filter bed, it will not clog, so it avoids the backwashing trouble and additional power consumption necessary for sand filter or other filter devices, and solves the clogging problem caused by the drying of filter material after accidental shutdown of treatment device. ZJDH high-efficiency sewage purifier is a set of sewage flocculation, sedimentation, adsorption, filtration, sludge thickening and other functions in one of the equipment.
1.2 test results
In the five months of the experiment, the test was carried out in six stages. The result of Table 1 showed that the test met the target.
2. Engineering application
2.1 scale of processing
In the treatment project of Zhujiang Paper Mill, two sets of 100 m3/h (13 m high) and two sets of 50 m3/h (11 m high) were used to treat the paddle and papermaking wastewater of yellow paper and white paper respectively. Six purifiers with a capacity of 100 (15) are used in the People's Paper Mill to treat paddle and papermaking wastewater from yellow and grey papermaking. Equipped with 2 sets of sludge thickening tank and dosing system, regulating sludge scraper, sludge dewatering machine and other equipment. The total investment of the two projects is 5.9 million yuan and 9.8 million yuan, covering an area of 1,600 and 2,800 yuan, respectively. ZJDH high-efficiency sewage purifier is used in Guangzhou No. 1 City Carton Plant. After sewage treatment, it is reused in papermaking production, which makes the plant reach the advanced level of 1 ton water paper.
2.2 process flow
Compared with the test process, the equipment such as adjusting tank scraping clay, adding medicine system after pump, sludge dewatering machine and so on were added.
2.3 operation effect
The technical characteristic of ZJDH high-efficiency sewage purifier is that no filter material or filler is used, and the flocculant sediment formed by the reaction of suspension and flocculant in the sewage of advanced production mode is used to form adsorption filtration order to purify the continuously entering sewage. The key is that the ZJDH high-efficiency sewage purifier can form a stable fluidization of the flocculated sediment in the sewage. Nowadays, the pollutants play the role of activated carbon, and the fresh flocculated sediment can promote the discharge of the old flocculated sediment, and always maintain the purifying effect of the purifier. Although it is only one level physicochemical treatment process, it can improve the efficiency of 10-20% compared with the same processes such as flotation and sedimentation.
After more than three years of operation, although the influent concentration changes greatly, the effluent is still good and stable. The monitoring results in Table 2 show that the removal rate of COD is 92.5%, BOD is 78.5%, and SS is 98.9%. The direct operating cost (0.25 yuan for pharmacy and 0.2 degrees for electricity consumption) is 0.38 yuan / ton of water.
ZJDH high-efficiency sewage purifier with primary physicochemical treatment process is used to treat the wastewater from paper making with waste paper regenerated paddle material. It has the advantages of simple process, reliable equipment, convenient management, less investment, less land occupation, high efficiency, low operating cost, and the treated wastewater can be discharged up to the standard and reused.
