投加新型生物流化填料的SBR反应器中试研究
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摘要
随着工农业的发展,污水的排放大大超出了水体的自净能力,因此,必须加大污水处理设施的建设和改造,从而改善水体环境。由于污水的排放标准日益严格,而好多污水厂由于设计的原因或者当时污水进出水指标都比较低的原因,导致现在大部分的污水厂排放不能达标。
北京市某污水厂采用传统的SBR工艺,由于当初的设计进水指标和实际的进水指标差距过大,因此在投产以后,出水指标一直比较高,不能达到北京市要求的《城镇污水处理厂污染物排放标准》(GB18918-2002)的一级A标准,甚至达不到二级排放标准。在这种情况下,设想可以通过投加某新型的流化填料,来强化传统的SBR工艺,以使出水达标。本试验就是为提过现场试验来证明这个设想,经过试验,得出了如下结论:
(1)在前期的对比试验中,投加新型生物填料的SBR反应器对工业废水排入造成的冲击负荷具有很强的适应能力,对BOD5、COD、NH_4-N、TN的去除率分别为:97%、92.6%、97.7%、64%,水指标为:BOD5=8mg/L,NH4-N=2.1 mg/L,TN=37 mg/L,除总氮以外全部达到了国家污水综合排放一级A的标准,而且总氮也达到了64%的高去除率。
(2)连续进水(试验过程中由于试验装置的问题,无法模拟连续进水,因此采用了分次进水)可以在一定程度上解决碳源不足的问题,可以相对地提高总氮的去除率。
(3)由于曝气完毕后,污水中的碳源已经很少,在沉降时的厌氧反硝化非常有限,去除率不到1%,为了解决碳源不足,应该采用前置反硝化,为反硝化提供充足的碳源。
(4)处理水量由模拟污水厂处理1万吨增加到3万吨,出水指标仍然能够达到略好于污水厂出水的效果,其中COD、氨氮都能达到国家要求的一级A排放标准。因此,投加填料的SBR反应器相对于传统的SBR反应器来说,可以明显的增大处理效率,而且非常明显。
(5)试验采用与污水厂相同的曝气管,而且污水厂的SBR池要比试验装置的水深大2.7倍,就水深方面的影响来说,污水厂的氧利用率应该更高一些。污水厂的运行汽水比一直在20～23:1之间,而试验过程中,汽水比在13～20:1之间。因此,可以证明投加了流化填料的SBR反应器要比传统的SBR反应器的氧利用率更高,耗能更少。
(6)从试验过程中,可以观察到,投加填料以后,由于填料的作用,污泥在15分钟以后就基本沉降完毕,要比传统SBR的污泥沉降要快很多。因此,投加填料对于污泥的沉降是有利的。在实际应用中,由于可以相应缩短沉降时间,利于周期内其它工艺时间段的调节。
Along with the development of Industry and Agriculture, The quantity of sewage has surpassed the ability of water clean itself. So, more efforts should be made to build and improve the sewage treatment factory, and improve the quality of environment .Because the exhaustion standard is Increasingly stringent, more effluent can't meet the emission standards, the reason is that the standards of influent and effluent were lower in that time.
A Sewage Treatment Plant in Beijing used traditional the SBR craft, because the initial Influent indicator and actual Influent indicators had relatively big gap, after production, the effluent indicators has been unsatisfactory and could not achieve to the oneclass A exhaustion standard of (GB18918-2002) that Beijing requested, Even can not reach the second class exhaustion standard. In this case, the tentative plan may through adding some new fluidization padding to strengthen the traditional the SBR craft to make the effluent to reach the standards. This experiment is done to prove this tentative plan through the field test , and during the process, we get some conclusions as follows:
(1) As is shown by the comparative experimental results of theprior period, SBR reactor with new style biological padding has great adaptive capacity to load pulses resulted from inflow of industrialwaste water. The removal rate of BOD_5、COD、NH_4-N、TN are 97%、92.6%、97.7%、64% respectively. The BOD_5, NH_4-N and TN in theeffluent are 8mg/L, 2.1 mg/L,37 mg/L respectively. All three indexes can meet the first class criteria A specified in the Integrated Wastewater Discharge Standard except the TN. But removal rate of TN also reaches a relatively high level of 64%.
(2) Entering the wastewater continuously (in testing, as a resultof test equipment, was unable to simulate entering water continuously, therefore entered water to be possible at different times) , relief the problem that the carbon source was insufficient to a certain extent , and promote the removal effect of total nitrogen relatively.
(3) After the aeration, there was little carbon source in thewastewater, the anaerobic denitrification in the subsidence time was extremely limited, the removal rate was less than 1%, in order to solve the shortage of carbon source, pretage denitrification is a good choice, as it could provide sufficient carbon source for the denitrification.
(4) The simulated treatment of wastewater increased from10,000 tons to 30,000 tons, the effluent still was able to achieve a satisfactory result, COD and ammonia nitrogen could achieve therequirements of the one class A exhaustion standards. the treatmenteffect that the SBR reactor adding the padding is obviously superior than the traditional SBR reactor.
(5) The aeration tube that the experiment using was same toSewage Treatment Plant, moreover, the SBR ponds of Sewage Treatment Plant were 2.7 times deeper than the test equipment, the impact on water, Sewage Treatment Plants were better than experiment that in the rate of oxygen using .moreover, the ratio of gas to water that Sewage Treatment Plants are using was between 20:1 and 23:1, but in the testing, the ratio was between 13:1 and 20:1.Therefore,it may prove that the Oxygen utilization that the SBR reactor adding the padding was higher than the traditional SBR reactor, and was more saving energy.
(6) From the testing, the sludge could sediment basically in 15minutes after adding the padding, more quickly than the traditional SBR reactor, so it was useful to increase padding. In practical, since it could shorten the settling time accordingly, and it was helpful to adjust the other process cycle time .
北京市某污水厂采用传统的SBR工艺,由于当初的设计进水指标和实际的进水指标差距过大,因此在投产以后,出水指标一直比较高,不能达到北京市要求的《城镇污水处理厂污染物排放标准》(GB18918-2002)的一级A标准,甚至达不到二级排放标准。在这种情况下,设想可以通过投加某新型的流化填料,来强化传统的SBR工艺,以使出水达标。本试验就是为提过现场试验来证明这个设想,经过试验,得出了如下结论:
(1)在前期的对比试验中,投加新型生物填料的SBR反应器对工业废水排入造成的冲击负荷具有很强的适应能力,对BOD5、COD、NH_4-N、TN的去除率分别为:97%、92.6%、97.7%、64%,水指标为:BOD5=8mg/L,NH4-N=2.1 mg/L,TN=37 mg/L,除总氮以外全部达到了国家污水综合排放一级A的标准,而且总氮也达到了64%的高去除率。
(2)连续进水(试验过程中由于试验装置的问题,无法模拟连续进水,因此采用了分次进水)可以在一定程度上解决碳源不足的问题,可以相对地提高总氮的去除率。
(3)由于曝气完毕后,污水中的碳源已经很少,在沉降时的厌氧反硝化非常有限,去除率不到1%,为了解决碳源不足,应该采用前置反硝化,为反硝化提供充足的碳源。
(4)处理水量由模拟污水厂处理1万吨增加到3万吨,出水指标仍然能够达到略好于污水厂出水的效果,其中COD、氨氮都能达到国家要求的一级A排放标准。因此,投加填料的SBR反应器相对于传统的SBR反应器来说,可以明显的增大处理效率,而且非常明显。
(5)试验采用与污水厂相同的曝气管,而且污水厂的SBR池要比试验装置的水深大2.7倍,就水深方面的影响来说,污水厂的氧利用率应该更高一些。污水厂的运行汽水比一直在20～23:1之间,而试验过程中,汽水比在13～20:1之间。因此,可以证明投加了流化填料的SBR反应器要比传统的SBR反应器的氧利用率更高,耗能更少。
(6)从试验过程中,可以观察到,投加填料以后,由于填料的作用,污泥在15分钟以后就基本沉降完毕,要比传统SBR的污泥沉降要快很多。因此,投加填料对于污泥的沉降是有利的。在实际应用中,由于可以相应缩短沉降时间,利于周期内其它工艺时间段的调节。
Along with the development of Industry and Agriculture, The quantity of sewage has surpassed the ability of water clean itself. So, more efforts should be made to build and improve the sewage treatment factory, and improve the quality of environment .Because the exhaustion standard is Increasingly stringent, more effluent can't meet the emission standards, the reason is that the standards of influent and effluent were lower in that time.
A Sewage Treatment Plant in Beijing used traditional the SBR craft, because the initial Influent indicator and actual Influent indicators had relatively big gap, after production, the effluent indicators has been unsatisfactory and could not achieve to the oneclass A exhaustion standard of
(1) As is shown by the comparative experimental results of theprior period, SBR reactor with new style biological padding has great adaptive capacity to load pulses resulted from inflow of industrialwaste water. The removal rate of BOD_5、COD、NH_4-N、TN are 97%、92.6%、97.7%、64% respectively. The BOD_5, NH_4-N and TN in theeffluent are 8mg/L, 2.1 mg/L,37 mg/L respectively. All three indexes can meet the first class criteria A specified in the Integrated Wastewater Discharge Standard except the TN. But removal rate of TN also reaches a relatively high level of 64%.
(2) Entering the wastewater continuously (in testing, as a resultof test equipment, was unable to simulate entering water continuously, therefore entered water to be possible at different times) , relief the problem that the carbon source was insufficient to a certain extent , and promote the removal effect of total nitrogen relatively.
(3) After the aeration, there was little carbon source in thewastewater, the anaerobic denitrification in the subsidence time was extremely limited, the removal rate was less than 1%, in order to solve the shortage of carbon source, pretage denitrification is a good choice, as it could provide sufficient carbon source for the denitrification.
(4) The simulated treatment of wastewater increased from10,000 tons to 30,000 tons, the effluent still was able to achieve a satisfactory result, COD and ammonia nitrogen could achieve therequirements of the one class A exhaustion standards. the treatmenteffect that the SBR reactor adding the padding is obviously superior than the traditional SBR reactor.
(5) The aeration tube that the experiment using was same toSewage Treatment Plant, moreover, the SBR ponds of Sewage Treatment Plant were 2.7 times deeper than the test equipment, the impact on water, Sewage Treatment Plants were better than experiment that in the rate of oxygen using .moreover, the ratio of gas to water that Sewage Treatment Plants are using was between 20:1 and 23:1, but in the testing, the ratio was between 13:1 and 20:1.Therefore,it may prove that the Oxygen utilization that the SBR reactor adding the padding was higher than the traditional SBR reactor, and was more saving energy.
(6) From the testing, the sludge could sediment basically in 15minutes after adding the padding, more quickly than the traditional SBR reactor, so it was useful to increase padding. In practical, since it could shorten the settling time accordingly, and it was helpful to adjust the other process cycle time .
引文
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[2]国家环保总局.水和废水监测分析方法(第4版).北京:中国环境科学出版社,2002.
[3]沈耀良,王宝贞.废水生物处理新技术理论与应用.中国环境科学出版社.1999:80-88.
[4]彭永臻.SBR法五大优点.中国给水排水.1993:29-31.
[5]沈耀良,黄勇.固定化微生物污水处理技术.化学工业出版社2002:104-105.
[6]沈耀良,王宝贞.Linpo;废水生物处理工艺及应用.环境工程.1999,1(16):7-9.
[7]H.Reimann.The LINPOR-process for Nitrification and Denitrifieation.Wat.Sci.Teeh.1990,2(7-8),297.
[8]P.S.Gollarn.etc.three years of full-scale CAPTOR process operation at Moundsville WWTP.Wat.Sei.Tech..1994,29(10-11):175-181.
[9]J.A.Heidman.Pilot-Plant Evaluation of porous Biomass Supports.J.Env.Eng..1988,114(5):207.
[10]B.Rusten,ete..Moving Bed Biofilm Reactors and Chemical Precipitation for High Efficiency Treatment of Waste water from Small Communities.Wat.Sei.Teeh..1997,35(6):71.
[11]M.Morper.tec.Improvement of existing wastewater treatment plants effieieneies without enlargement of tankage by application of the LINPOR-proeess-CASES TUDIES.Wat.Sci.Tech..1990,22(7/8):207-215.
[12]李军,杨秀山,彭永臻.微生物与水处理工程[M].北京:化学工业出版社,2002.
[13]李杰,王亚娥,王志盈,等.海绵铁生物填料对生化处理效果的影响[J].水处理技术,2006,32(12):64-66.
[14]魏瑞霞,孙剑辉,陈金龙.悬浮填料-SBR工艺处理难降解青霉素制药废水的研究[J].环境污染治理技术与设备,2003,4(4):46-49.
[15]王沂,黄少斌.SBR-BAF组合工艺好氧反硝化脱氮[J].环境工程,2006,24(5):10-11.
[16]王亚宜,李探微,韦更生.序批式生物膜技术(SBBR)的应用及其发展[J].浙江工业大学学报,2006,34(2):213-219.
[17]王霞,刘俊良,马放.强化填料SBR工艺处理高浓度制药废水的研究[J].中国农村水利水电,2006,(3):65-66.
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