贠丹丹,王陸軍,郝同,梁碩,王聚燦,趙喬華
(北京沃爾德斯水務(wù)科技有限公司,北京 102300)
摘 要:目前水體環(huán)境污染嚴(yán)重,國家環(huán)保力度加大,新的標(biāo)準(zhǔn)愈加嚴(yán)格,城市污水處理廠必須進(jìn)行提標(biāo)改造。針對內(nèi)蒙古某污水處理廠存在的現(xiàn)實(shí)問題,提出改造難點(diǎn),并根據(jù)水質(zhì)指標(biāo)分析探索出提標(biāo)改造路線為原處理工藝出水+磁混凝沉淀池--深床反硝化濾池--臭氧氧化池--消毒—中水回用,使污水廠達(dá)到地表IV類水標(biāo)準(zhǔn)。污水深度處理效果明顯,適用于對出水水質(zhì)要求高,出水回用工程。選擇深度處理工藝時(shí),要根據(jù)處理水質(zhì)、工程規(guī)模和出水水質(zhì)要求進(jìn)行分析實(shí)驗(yàn)確定。
關(guān)鍵詞:城市污水處理廠;提標(biāo)改造;IV類水標(biāo)準(zhǔn)。
Analysis of Technical Route for Upgrading the Current Effluent Standard of Urban Sewage Treatment Plants to Environmental Quality Standard for Surface Water Class IV
Abstract: At present, due to severe water pollution, Our country is investing more efforts and taking new and more strict standards to protect environment. Under such circumstances, urban sewage treatment plants have to be upgraded. As for the issues in a Inner Mongolia sewage treatment plant, We pointed out the difficulties in the current plant transformation, analyzed data of water quality and discovered a new transforming route(original process+magnetic coagulation tank+Deep-bed denitrification filter tank+ozone oxidation+sterilization→reclaimed water), by applying which, the quality of effluent can meet the standard of surface water class IV. This process is perfectly suitable for reclaimed water projects or projects demanding high water quality of effluent because of its outstanding efficiency in sewage advanced treatment. When we have to choose a process for advanced sewage treating, we should always take the quality of influent water quality, scale of the project and the quality of effluent water into account, analyse the data and find the best solution.
Key words: Urban sewage treatment plant; upgrading; Surface water quality Class IV standard.
1 背景
目前水體環(huán)境污染嚴(yán)重,我國環(huán)保力度不斷加強(qiáng),制定了節(jié)能減排目標(biāo),同時(shí)將城鎮(zhèn)污水處理廠的污染物排放指標(biāo)不斷提高[1-3]。從2003年7月1日起《城鎮(zhèn)污水處理廠污染物排放標(biāo)準(zhǔn)》(GB18918-2002)開始實(shí)施,該標(biāo)準(zhǔn)對污水處理廠的出水COD、BOD5、SS、TN、NH3-N、TP及大腸桿菌有了更嚴(yán)格的規(guī)定。2006年提出修改單公告[4],明確指出“城鎮(zhèn)污水處理廠出水排入國家和省確定的重點(diǎn)流域及湖泊、水庫等封閉、半封閉水域時(shí),必須執(zhí)行一級A標(biāo)準(zhǔn)”。
各地區(qū)根據(jù)地方情況制定了當(dāng)?shù)厮h(huán)境污染物排放限值,如天津標(biāo)準(zhǔn)把TN定為10mg/L,氨氮為1.5(3.0)mg/L。此外,還有環(huán)渤海流域標(biāo)準(zhǔn)、環(huán)太湖流域標(biāo)準(zhǔn)、巢湖流域標(biāo)準(zhǔn)、廣州的類五類標(biāo)準(zhǔn)等都是在國家地表水四類和三類水的標(biāo)準(zhǔn)下適當(dāng)放寬TN和氨氮的標(biāo)準(zhǔn)下形成各自的標(biāo)準(zhǔn)。之后《地表水環(huán)境質(zhì)量標(biāo)準(zhǔn)》(GB3838-2002)IV類、III類水的提出,進(jìn)一步對各污染物指標(biāo)更嚴(yán)格的限定(相關(guān)排放標(biāo)準(zhǔn)表1列出)。