交替式厌/缺氧-好氧双膜反硝化除磷工艺

采用某污水处理厂A²/O工艺中的活性污泥为种泥,以模拟生活污水为对象,考察了交替式厌/缺氧-好氧双膜反硝化除磷工艺的启动与运行特性,并采用高通量测试技术分析系统除磷污泥的菌群结构。通过60天的启动试验,系统内反硝化聚磷菌占聚磷菌总数的比例由21.3%提高到94.4%,出水磷在0.6mg/L左右。通过逐步增加进水氨氮的方法运行2个月,系统的脱氮除磷效果稳定。在进水P浓度为6.4mg/L,保持进水N/P比为8.8,交替厌/缺氧-好氧双膜反硝化除磷工艺效能最优,可达0.12kgN/(m³?d)和0.018kgP/(m³?d),出水总磷(TP)0.8mg/L,总氮(TN)12mg/L,出水COD、NH₃-N和TN达到国家综合排放标准GB18918-2002一级A排放标准。周期试验中,pH值、氧化还原电位(oxidation-reduction potential,ORP值)均可作为厌氧释磷的控制参数,ORP也可指示缺氧吸磷的终点。典型周期内硝酸盐、亚硝酸盐的消耗量与磷的吸收量基本呈线性关系。系统内污泥多样性约为种泥的0.5倍,在“门”、“属”分类级别上分别以Proteobacteria、Xanthomonadales-nobank为主。     

有机进样-电感耦合等离子体发射光谱法测定汽油中的磷含量

采用有机进样-电感耦合等离子体发射光谱法测定汽油中的磷含量。以异辛烷为稀释剂,按照m(汽油)∶m(异辛烷)=1∶3加以稀释后直接进入ICP-AES(电感耦合等离子体发射光谱)仪测定。结果表明,该方法工作标准曲线在0~10 mg/kg(即稀释前磷含量在0~40 mg/kg)范围内线性关系良好,r=0.999 2,方法检出限为0.156 mg/kg,相对标准偏差5.0%,回收率在96.3%~105.8%之间。     

Denitrification and Dephosphatation by Anaerobic/Anoxic Sequencing Batch Reactor

Removal of denitrifying phosphorus was verified in a laboratory anaerobic/anoxic sequencing batch reactor (A/A SBR). The results obtained demonstrated that the anaerobic/anoxic strategy can enrich the growth of denitrifying phosphorus removing bacteria (DPB) and take up phosphate under anoxic condition by using nitrate as the electron acceptor. The phosphorus removal efficiency was higher than 90% and the effluent phosphate concentration was lower than lmg·L-1 after the A/A SBR was operated in a steady-state. When the chemical oxygen demand(COD) of influent was lower than 180mg·L-1, the more COD in the influent was, the higher efficiency of phosphorus removal could be attained under anoxic condition. However, simultaneous presence of carbon and nitrate would be detrimental to denitrifying phosphorus removal. Result of influence of sludge retention time (SRT) on denitrifying phosphorus removal suggested that the decrease of SRT caused a washout of DPB and consequently the enhanced biological phosphorus     

Strategies of valorization of sludge from wastewater treatment

Sludge is regarded as a potential source to achieve valorization via strategies such as resource recovery, sludge based adsorbents preparation, bioflucculants production, sludge manufacturing construction materials preparation, sludge composting and thermal valorization, which are currently common and effective strategies. Appropriate treatment strategies of sludge are of great importance worldwide for the fast growing population and rapidly increasing waste. This mini review summarized some widely used and effective strategies to achieve sludge valorization based on whether the strategy would utilize or reuse the potential of sludge to obtain valuable product and eliminate secondary pollution. Anaerobic digestion of sludge is perceived as a potentially cost‐effective method to achieve sludge reduction and resource recovery including carbon, nitrogen, phosphorus resource recovery coupled with other technologies. Utilizing sludge as raw material for preparation of valuable products including sludge based adsorbents, bioflocculants and construction materials is another aspect to achieve sludge valorization. Sludge composting and thermal valorization are also introduced in the mini review since the two strategies could also achieve sludge valorization. In addition, the strategies mentioned were discussed and analyzed in the mini review from environmental and economic aspects. © 2017 Society of Chemical Industry     

外加碳源类型对A2/O-BCO系统脱氮除磷性能的影响

反硝化除磷系统可实现氮、磷的同步去除,但在处理实际低C/N污水时,常需补充碳源以解决碳源不足的问题。采用A²/O-BCO（anaerobic anoxic oxic-biological contact oxidation）反硝化除磷系统,通过投加两种常用的外碳源控制进水C/N在4.3左右,考察碳源类型（丙酸钠、乙酸钠）对A²/O-BCO系统长期运行效果的影响,并采用批次试验进一步探究不同外加碳源条件下活性污泥的内碳源贮存和利用特性。结果表明：碳源种类的变化会改变微生物的底物贮存和利用特性,进而影响系统的脱氮除磷效果。当采用丙酸钠为外加碳源时,PO₄^3--P去除效果稳定在94%左右,实现了磷的高效去除,但TIN的去除率仅为70.82%;而以乙酸钠为外加碳源时,系统TIN的平均去除率可以达到74%,但磷的出水浓度出现波动现象,平均去除率仅为89.90%。碳源转化分析表明,厌氧条件下,进水丙酸钠含量增多,PHV的合成比例增加,相反,乙酸钠含量增多,PHB合成比例增多;缺氧条件下,DPAOs对PHB和PHV的降解效果与其含量相关,丙酸钠作为外碳源时,PHV的降解速率高且微生物产能效率高,因此PO₄^3--P吸收速率较快。此外,本文提出了不同外加碳源条件下系统的优化运行策略。     

磷酸酯中结合磷与无机磷的分析测定

将试样在硝酸、硫酸、高氯酸中分解 ,用钒钼酸铵法以 72 1型分光光度计测定阴离子表面活性剂磷酸酯中的无机磷、结合磷的质量。     

阻燃抗熔滴PET的制备与性能表征

将磷系阻燃剂2-羧乙基苯基次磷酸(CEPPA)、三聚氰胺氰尿酸盐(MCA)复配成膨胀型阻燃体系,在合成聚酯(PET)的酯化过程中加入到反应体系内,制备了一系列不同磷氮比的阻燃抗熔滴PET;对其热性能、成炭情况以及燃烧性能等进行表征。结果表明:磷系阻燃剂的加入可以显著提高PET的阻燃性能,同时加入MCA后,改性PET的成炭性能和抗熔滴性能明显得到改善,相对未添加阻燃剂的纯PET,其极限氧指数由23%提高到29%,垂直燃烧性能达到V-0级,但抑烟性能没有明显改善;随着阻燃剂的加入,改性PET的热稳定性提高;在一定的添加量下,添加少量MCA,与CEPPA协效作用最好。     

紫外光催化氧化法消解循环水中HEDP

为快速消解循环水中的羟基亚乙基二膦酸(HEDP),利用XPA系列光化学反应仪,采用紫外光催化氧化法对循环水中的HEDP进行消解。研究了氧化剂种类及用量、消解时间、p H等参数对HEDP消解率的影响,确定了最佳反应条件。实验结果表明:当氧化剂Na2S2O8质量浓度为1.0 g/L,紫外光照时间为8 min,p H为7左右时,HEDP的消解率可以达到98%以上。实验测定值的相对标准偏差﹤1%,精密度较高。该方法简单快速,重现性好,具有良好的应用前景。     

超韧无卤阻燃尼龙6防暴服专用料的研制

采用双螺杆挤出加工工艺,通过添加不同组分制得超韧无卤阻燃尼龙(PA)6材料,比较了不同黏度PA6、增韧剂、阻燃剂及加工工艺对材料性能的影响。结果表明,中黏搭配低黏PA6材料可获得最佳的冲击性能和加工性能;在添加15份马来酸酐接枝乙烯–辛烯共聚物增韧剂时增韧效果最好;小粒径、高含量(红磷)红磷母粒的阻燃效果较好且对体系的力学性能影响较小;Mg(OH)2具有很好的协效阻燃和消烟作用,在添加量为3份时效果最佳;适当的螺杆组合可提高体系的阻燃稳定性。     

优化配酸工艺,提高消防级磷酸一铵产品品质

介绍消防级磷酸一铵的生产工艺流程和产品质量要求,重点对配酸工艺的优化改造进行阐述。针对消防级磷酸一铵主含量(w(P_2O_(5水溶))/w(P_2O_(5总)))主要受配制混合磷酸中杂磷质量比(w(总杂质)/w(P_2O_(5总)))稳定性的影响,对配酸槽计量装置进行了优化改造。运用流体流量与截面积和通过该截面积流速的关系,在配酸槽增设液位计量刻度尺,可根据工艺配酸要求,利用液位与流量对照表进行准确配酸。改造后,混合磷酸的杂磷质量比波动小,消防级磷酸一铵主含量稳定,保证了消防级磷酸一铵产品的质量。