【作者】 曹贵华；

【导师】 黄勇；

【作者基本信息】 苏州科技学院 ， 环境工程， 2009， 硕士

【摘要】 目前应用较多的常规生物脱氮除磷工艺由于污泥混合培养使得系统存在碳源、泥龄、硝酸盐等矛盾,导致氮、磷不能同时高效稳定去除;尤其利用常规工艺处理低浓度废水时,系统会长期在低有机负荷状态下运行,无法为微生物提供足够的养分,降低微生物活性,从而影响污染物达标排放。本实验在工程实验条件下,采用新型废水生物脱氮除磷工艺对低浓度城市生活污水的处理进行了研究,旨在提高处理效率,简化运行操作,实现有机物、氮、磷等污染物同时达标排放。本研究在总容积为165m3的BICT装置上,对实际条件下BICT工艺处理低浓度城市污水的特性进行了初步研究,并在运行过程中发现,污泥的混合培养可能并非是制约低浓度生活污水中氮磷处理达标的主要因素,因此利用BICT工艺设备,进行了具有污泥转移的SBR工艺(强化SBR)处理低浓度废水的研究。主要得到以下结论:(1)BICT工艺能够在处理能力由190m3/d提高到260m3/d,水力停留时间为13.67h,进水有机负荷为0.35kgCOD/m3.d条件下可以达到较好的出水效果。泥龄为15天,周期为4.5h,充水比为1/2,污泥回流比为30%,系统COD、氨氮、TN、TP出水浓度分别为45mg/l、4.1mg/l、8.6mg/l、0.1mg/l,去除率分别为65%、60%、18%、88%,出水可达GB18918-2002一级A标准。(2)采用具有污泥转移功能SBR工艺在不影响处理达标前提下能够有效提高处理能力。采用30%的污泥回流比可将处理能力由240吨/天提高到310吨/天;此时系统水力停留时间为8.52h,进水有机负荷为0.5kgCOD/m3.d,系统运行模式为:进水+进水曝气+曝气+沉淀+出水,相应的时间为30min、30min、30min、30min、60min,运行周期为3h。此条件下出水COD、氨氮、TN、TP浓度分别为45mg/l、0.3mg/l、7.9mg/l、0.17mg/l,去除率分别为70%、98%、48%、87%,出水可达GB18918-2002一级A标准。(3)污泥转移可提高系统反应阶段的污泥浓度,30%污泥回流比下进水结束后SBR反应器中的污泥总量比无污泥转移的情况提高10%;出水阶段可降低反应器中的污泥总量,有利于增加充水比。这是提高系统处理能力的重要原因。(4)污泥转移可改善污泥沉降性能,30%的污泥回流比下系统污泥SVI值由无污泥转移时的140降低为93左右;还可改善系统除磷性能,实现聚磷菌强化除磷。这表明在系统中设置厌氧生物选择区能强化释磷条件、筛选絮凝性强的微生物,是十分必要的。更多还原

【Abstract】 As conventional biological nitrogen and phosphorus removal processes with carbon、sludge age、nitrate and other issues which makes the N, P highly efficient and stable remove poorly at the same time,due to the same mixed-culture microorganism in the system;In particular, when using conventional process to treat the low concertaion urban sewage, the system will be in the low load state, which can not provide sufficient nutrients for micro-organisms, so that more of these conflicts intensified. In the works conditions, This experiment will use new biological process for the low-concentration wastewater treatment, in order to improve the efficiency、simplify the operation and to ensure that pollutants can be discharged standard.Utilize the BICT device, the total volume is 165 m3 , which carried out the preliminary study about dealing with the low concentrations sewage. At the same time, we found that sludge mixed culture may not be the main constraints factors to deal with low concentration sewage,so use of BICT equipment to treat low concentration wastewater with enhanced SBR process. The experimental results as follows:(1) The BICT process has good effect at handling capacity from 190 m3/d to 260 m3/d、HRT 13.67h and influent organic load 0.35kgCOD/m3.d. Under the controlled conditions: SRT is 15d, cycle is 4.5h,filling rate is 1/2,recycling rate of sludge is 30%;The average removal rate of COD、NH3、TN、TP are 65%、60%、18%、88%, and the Effluent concentration up to GB18918-2002 grade A standards.(2) the SBR process with sludge transfer (enhance SBR process) can effectively increase its handling capacity without affecting the processing. Using 30% of the sludge reflux ratio can raise handling capacity from 240 T/d to 310 T/d, when the HRT is 8.52h, the organic load is 0.5kgCOD/m3.d,and Under the controlled conditions: filling(30min), filling/aeration(30min), aeration(30min), sedimentation(30min), decanting(60min); The effluent COD、ammonia nitrogen、TN、TP concentrations are 45mg/l、0.3mg/l、7.9mg/l、0.17mg/l,The average removal rate of COD、NH3、TN、TP are 70%、98%、48%、87%, and the Effluent concentration up to GB18918-2002 grade A standards.(3) Sludge transfer in the system can improve the response phase of the sludge concentration, and can reduce the decanting phase of the sludge concentration, which is one of the main reasons to improve the handling capacity.(4) Sludge transfer could improve the performance of sludge settlement;Using 30% of the sludge reflux ratio, Sludge settlement index can reduce from 140 to 93. Sludge transfer can also improve Phosphorus Removal Performance,to achieve PAOs’enhanced phosphorus removal. The above two points just show that the enhanced SBR’s anaerobic biological selector not only provide places for PAOs to achieve enhanced phosphorus release, but also filter out the strong flocculation microbial.更多还原