【作者】 陈磊；

【导师】 王宗平； 郭刚；

【作者基本信息】 华中科技大学 ， 市政工程， 2022， 硕士

【摘要】 我国沿海城市污水中有机碳源普遍不足,含硫物质较高,增加了污水处理厂稳定运行的难度。硫循环协同反硝化除磷工艺利用硫还原菌和硫氧化菌的协同,能适应低碳源含硫环境,实现碳、氮、磷污染物的同时去除,但受聚糖菌影响处理效果会发生波动甚至恶化,而单质硫具有提高硫细菌竞争优势的潜在能力。因此本研究对硫细菌和聚糖菌进行了共同富集,并研究了不同浓度碳源条件下单质硫对硫细菌与聚糖菌竞争关系的短期、长期影响。首先,在序批式反应器中对硫细菌与聚糖菌进行了580 d的富集培养,结果表明:通过投加过量硝酸盐(>100 mg N/L),以及多次增加-恢复进水碳源投量,能够实现硫细菌和聚糖菌的共同富集,且硫还原菌、硫氧化菌和聚糖菌的相对丰度在稳定运行阶段分别达到了3.1%、13.5%和13.2%。其次,进行了不同浓度碳源条件下(400、200、100和0 mg COD/L),单质硫(0.53 g)对硫细菌与聚糖菌竞争关系的短期(10 h)影响研究,结果表明:在单个周期内(10 h),单质硫对硫细菌与聚糖菌体内储存的内碳源转化量、氮磷去除效果、碳源吸收速率等影响不大;碳源充足时(400 mg COD/L),单质硫的投加短期内可促进更多的聚硫合成(21.8 mg S/g VSS),有利于硫细菌的生长;碳源较低或严重不足时(200、100和0 mg COD/L),单质硫对硫细菌与聚糖菌的竞争短期内影响不显著。最后,参照短期实验条件,进行了硫细菌与聚糖菌长期竞争实验(100 d),发现碳源充足时(400 mg COD/L),单质硫投加可强化硫代谢转化,抑制内碳源的代谢转化,硫细菌在与聚糖菌长期竞争中处于优势地位;碳源较低时(200 mg COD/L),有限的碳源限制了硫还原菌的生长,但单质硫能够维持硫氧化菌的繁殖,无法抑制聚糖菌在系统中的富集;碳源严重不足时(100和0 mg COD/L),硫还原菌和聚糖菌均不能获得充足碳源,生长受到抑制,但单质硫可强化硫氧化菌的竞争优势。综上,在低碳源含硫污水中投加单质硫,能够诱导多硫化物的生成,促进硫细菌对单质硫的利用,提高其竞争优势,为低碳源含硫污水的处理提供新的理论支撑。更多还原

【Abstract】 In China,the organic carbon source is generally insufficient and sulfur-containing substances is high in coastal urban sewage in China.It increases the difficulty of WWTPs operation.The denitrifying sulfur conversion-associated enhanced biological phosphorous removal process(DS-EBPR)that adapts to the sulfur-containing wastewater of insufficient carbon source,can employ sulfur-reducing bacteria(SRB)and sulfur-oxidizing bacteria(SOB)to realize the simultaneous removal of carbon,nitrogen and phosphorus pollutants.Nevertheless,glycogen-accumulating organisms(GAOs)compete with sulfur bacteria(SRB and SOB),always causing fluctuations and deterioration in treatment efficiency of DS-EBPR.Besides,elemental sulfur can provide the potential to improve the competitive advantage of sulfur bacteria.Hence,in this study,sulfur bacteria and GAOs were enriched together in a sequence batch reactor.Then,the short-term and long-term effects of elemental sulfur addition on the competition between sulfur bacteria and GAOs under different concentrations of carbon sources were studied.Firstly,sulfur bacteria and GAOs were enriched for 580 days in a sequence batch reactor.The results showed that the co-enrichment of SRB,SOB and GAOs could be realized by adding excessive nitrate(> 100 mg N/L)and increasing/restoring influent carbon source for several times.Besides,after entering the stable operation stage,the relative abundances of SRB,SOB and GAOs reached 3.1%,13.5% and 13.2%,respectively.Secondly,the short-term(10 h)effects of elemental sulfur(0.53g)on the competition between sulfur bacteria and GAOs were explored under different carbon sources(400,200,100 and 0 mg COD/L).The results illustrated that the existence of elemental sulfur had little effect on the conversion of internal carbon sources,the removal efficiency of nitrogen and phosphorus,and the absorption rate of carbon source.When the carbon source was sufficient(400 mg COD/L),the addition of elemental sulfur promoted polysulfide synthesis(21.8 mg S/g VSS)in the short term,which was beneficial to the growth of sulfur bacteria.Meanwhile,when the carbon source was low or seriously insufficient(200,100 and 0 mg COD/L),the elemental sulfur had no significant influence on the competition between sulfur bacteria and GAOs in short term.Finally,according to the operating conditions of short-term experiment,the long-term competition experiment between sulfur bacteria and GAOs(100 days)was carried out.It was found that when the carbon source was sufficient(400 mg COD/L),the addition of elemental sulfur enhanced sulfur metabolism and reduced the transformation of internal carbon source.Sulfur bacteria had a dominant position in long-term competition with GAOs.When the carbon source was low(200 mg COD/L),the limited carbon source restricts the growth of SRB.The elemental sulfur could maintain the growth of SOB,but could not inhibit the enrichment of GAOs in the system.As the carbon source was seriously insufficient(100 mg COD/L and 0 mg COD/L),SRB and GAOs could not obtain sufficient carbon source for biochemical reaction,and the growth of them was both restricted.Whereas,elemental sulfur promoted the growth of SOB,making it occupied an advantage in the competition.Overall,adding elemental sulfur that can induce the generation of polysulfide promotes the utilization of elemental sulfur by SRB and SOB,improving their competitive advantages,which provides a new technical option and theoretical support for the treatment of sulfurcontaining wastewater with insufficient carbon source.更多还原