环境工程专业 外文翻译啤酒废水处理.docx

1、环境工程专业 外文翻译啤酒废水处理英文原文Sludge reduction during brewery wastewater treatment by hydrolyzation-food chain reactor systemAbstract: During brewery wastewater treatment by a hydrolyzation-food chain reactor (FCR) system, sludge was recycled to the anaerobic segment. With the function of hydrolyzation acidi

2、fication in the anaerobic segment and the processes of aerobic oxidation and antagonism, predation,interaction and symbiosis among microbes in multilevel oxidation segment, residual sludge could be reduced effectively. The 6-month dynamic experiments show that the average chemical oxygen demand (COD

3、) removal ratio was 92.6% and average sludge production of the aerobic segment was 8.14%, with the COD of the influent at 9601720 mg/L and hydraulic retention time (HRT) of 12 h.Since the produced sludge could be recycled and hydrolyzed in the anaerobic segment, no excess sludge was produced during

4、the steady running for this system.Keywords hydrolyzation, multilevel oxidation, excesssludge, reduction1. IntroductionDuring the 1980s, the main brewery wastewater treatment locally and abroad was the aerobic technique, then the hydrolytic-aerobic techniques showed up in the late 1980s. Currently,

5、the main technology for brewery wastewater treatment are the activated sludge process, contact oxidation process, and hydrolytic-aerobic techniques. Although these techniques have some advantages of their own, they all have a problem with sludge disposal 1. The sludge production is about 60% of the

6、chemical oxygendemand (COD) removal amount for conventional activated sludge technology, and about 30% for conventional biofilm method 2. The cost of sludge disposal had become an economic burden of the sewage plant. The sludge produced may bring about secondary pollution.Therefore, the study on wat

7、er treatment processes that can lead to sludge reduction is becoming one of the important issues in sewage treatment. This study adopted principles of cleaner production. With the hydrolyzation-acidification in anaerobic segments, residual sludge could be translated into soluble organicmatter and sm

8、all organic molecules, then enter the aerobic segment as organic load. A series contact oxidation system for food chain reactor (FCR) was applied in the aerobic segment to form amanual biogeocenose and food chain. Based on biological theory, the longer the food chain is, the more energy lost, and th

9、us less energy that can be used for growth of the organisms, and less biomass left in the ecosystem as a result. Therefore, prolonging the food chain and strengthening the predation of microzoans in the food chain are both effective in sludge reduction. Zero Discharge of residual sludge was achieved

10、 during the brewery wastewater treatment by a hydrolyzation-FCR system. This study explored the mechanism of sludge reduction during the hydrolyzation process and multilevel oxidation process。2 Material and methods2.1 Characteristics of wastewaterThe experimental water is a man-made simulant brewery

11、 wastewater, which contains bottled beer, NH4Cl, KH2PO4,MgSO4, and CaCl2. The biodegradability index, the ratio of concentrations of biochemical oxygen demand for 5 days (BOD5) and COD, is about 0.40.5. Table 1 shows the main water quality properties.2.2 Experimental apparatus and experimental flow

12、The experimental apparatus was a hybrid biological reactor (Shanghai Best Environmental Technology Corporation, Shanghai, China) as shown in Fig. 1. The aerobic sect of FCR was divided into four parts along the treatment process and their efficient volumes were w 0.12, 0.09, 0.09, and 0.06 m3, respe

13、ctively (the ater is 0.97 mdeep). Sewage was poured into the reactor, then flowed into each tank, with the function of gravitational action and a rotameter adjusting the flow. Volumetric ratio of the hydrolyzation segment and multilevel oxidation segment was 0.8:1. Sewage was treated during the hydr

14、olyzation segment and all tanks of the multilevel oxidation segment, then flowed into a sedimentation tank where sludge and water were separated. The excessive sludge was discharged regularly, and recycled into the hydrolyzation-acidification segment. At the bottom of the multilevel oxidation segmen

15、t was an aeration device. Fig. 1 Diagram of the experimental device1. high-positioned flume, 2. volume-constant flume, 3. hydrolyzation tank, 4. multilevel oxidation FCR system, 5. fillers, 6. baffle, 7.entering-water pipe for sedimentation tank, 8. sedimentation tank, 9. outlet pipe, 10. discharge

16、pipe, 11. aeration device, 12. rotameter,13. ride, 14. aeration diffuse2.3 Operation parametersDuring the two-month experimental duration, the room temperature was in the range of 1427uC. The total hydraulic retention time (HRT) of this system was 12 h,and the HRT of the hydrolyzation segment was 5.

17、5 h.Concentrations of dissolved oxygen were 26 mg/L.2.4 Analysis methodsThe indicators of source water were measured according to monitoring and analytical methods of water and wastewater3.3 Experimental results and discussion3.1 Removal effect of CODFigure 2 shows the COD removal effect of the hydr

18、olyzation-FCR system during the steady running time period When the concentrations of COD in the influent were 9601720 mg/L, and HRT was 12 h, the removal ratioof COD was above 90%, and the concentration of COD in the effluent was 4595 mg/L. The water quality of the effluent met the first class of t

19、he Integrated Wastewater Discharge Standard 4.Fig. 2 COD removal efficiency during the continuous running time period3.2 Sludge removal effectSludge produced by this system was recycled to the hydrolyzation segment where it was hydrolyzed and translated into organic load and poured into the multilev

20、el oxidation segment. This part of the organic matter was mostly released as energy except for a relatively small portiontranslated into organism. In a real operation, there might be negative growth of sludge in the hydrolyzation segment since the microbe of which needs lots of energy as well. As a

21、result, the recycled sludge could be a supply for the hydrolyzation segment. Theoretically, Zero Dischargeof residual sludge could be achieved and the experimental results have verified this point. The sludge production of the FCR system was continuously investigated during the two-month steady runn

22、ing period, and the relationship between total sludge production and total COD removal amount was analyzed. Figure 3 shows that the ratio of sludge production was 6%10%, and the average sludge production was 8.15%, which is about 15% of conventional activated sludge technology and 25% of conventiona

23、l biofilm method. The results show that the FCR system has great effect on sludge reduction.Fig. 3 Sludge production of the multilevel oxidation segment during the steady running time period4 Mechanism analysisThe biological function of the carrier and the running mode of multilevel oxidation FCR ma

24、de the concentration of the sewage gradient alone with current, which formed three different zones in the tank: polysaprobic, mesosaprobic, and oligosaprobic zones. Each zone has a different microorganism community (from the basic to advanced), which formed a relatively integrated ecological structu

25、re and a food chain as bacteria-protozoa-metazoa-daphnia. By the analysis of the FCR system, much more microbes in different kinds and quality were found than the conventional aerobic process. As a result, the food chain in this system was more complicated than other processes. Figure 4 shows the co

26、mpositions of the food chain of the FCR system. Based on biological theory, the food chain is getting longer and more complex, the relationship between microbes in the food chain is more complex. Through the process of antagonist, predation, interaction and symbiosisamong microbes, the microbe syste

27、m is balanced, and none of the specific population could over-develop 8,9. Higher trophic degree of the predator,more energy consumed, and less energy that can be used for the growth of organisms 1012. With the effect of all these factors, the ecosystem could maintain a relatively stable term. As a

28、result, less sludge would be produced in practice.Fig. 4 Compositions of the food chain of the FCR system5 Conclusions(1) When the concentrations of COD in the influent were 12001800 mg/L, HRT was 12 h, and average COD removal ratio was 92.6%. Zero Discharge of residual sludge was achieved during th

29、e steady time running for this system, since the produced sludge could be recycled and hydrolyzed to the anaerobic segment. Without sludge disposal equipment added, this method could have both economic and environmental profit in practice.(2) The process of multilevel oxidation FCR could form a micr

30、obe ecosystem just like the natural microbe ecosystem, and a fully developed food chain. Through the processes of antagonism, predation, interaction, and symbiosis among microbes, sludge was effectively reduced. During the steady running of multilevel oxidation FCR, the average sludge production of

31、the FCR system was 8.15%.1 Department of Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China2 Department of Environmental Science & Engineering, Harbin Institute of Technology, Harbin 150090, ChinaReferences1. Chen Y P, Fu Y S, Li X M, et al. Characters and

32、 treatment of brewery wastewater. Pollution Control Technology, 2003,16(4): 148151 (in Chinese)2. Andreottola G, Foladori P, et al. A review and assessment of emerging technologies for the minimization of excess sludge production in wastewater treatment plants. Environmental Science & Health, 2006, 41(9): 185318723. State Environmental Protection of China. Analysis Water and Wastewater. 4th ed.Beijing: Chinese Environmental Science Press, 2002, 88223 (in Chinese)4. State Quality and Technique Supervision Bureau. Integrated Wastewater Discharge Standard (G