Fenton-水解酸化-接触氧化处理模拟磷霉素钠制药废水

对模拟磷霉素钠制药废水进行Fenton-水解酸化-接触氧化小试处理实验,考察了COD、有机磷的去除效果,并对处理前后的废水进行了GC-MS分析。结果显示,增加了Fenton预处理后磷霉素钠制药废水的COD和有机磷分别降低到100和2 mg/L,去除率均可达87%以上,出水COD满足化学制药行业污染物排放标准(GB 21904-2008);Fenton过程对制药厂废水中的复杂有机物去除效果明显,GC-MS结果表明,出水中基本检测不到复杂有机物。与制药厂采用的水解酸化-接触氧化处理效果相比,增加Fenton预处理可以提高废水的可生化性和系统的处理效率。     

O3氧化工艺处理黄连素制药废水研究

采用臭氧（O3）氧化法处理含高浓度黄连素和COD的制药废水,探讨了废水初始pH、O3投加量及初始黄连素浓度等因素对O3氧化过程的影响,确定了O3氧化技术处理黄连素制药废水的最佳操作条件。结果表明,O3能够有效分解废水中的黄连素,降低其COD浓度;黄连素浓度为700mg／L、COD为3500mg／L、pH为0．88的废水,进气O3浓度为14．05mg／（L·min）,处理时间为180rain（即投加量为2529mg／L）时,黄连素和COD的降解率分别可达77．46％和41．28％,BOD,／COD比（B／C比）从0．06提高到0．34,增加了4．7倍;随着废水中初始黄连素浓度的升高,废水COD降解率逐渐降低。O3氧化法是一种有效的黄连素制药废水预处理技术,可以大大提高废水的可生化性。     

利用白云石回收污泥厌氧消化液中的磷

为经济有效地从污泥厌氧消化液中回收磷,构建了以白云石提供钙镁源的磷回收方法,探讨了磷回收的工艺条件与效果。通过盐酸酸化厌氧消化液以降低其碳酸盐含量,同时利用白云石溶于冷稀盐酸的特性使其钙镁缓慢释放到酸化的厌氧消化液中形成第一步磷回收体系,考察体系酸化pH、白云石与厌氧消化液的固液比以及反应pH对白云石的钙镁释放和磷回收效果的影响;第一步磷回收后的上清液为第二步厌氧消化液磷回收提供钙镁源,研究投加钙磷摩尔比对磷回收效果的影响。实验结果表明,当固液比为5.0时,在酸化pH为4.0～4.5且酸化溶出时间为10 h以及反应pH为9.0的条件下,第一步磷回收产物以磷酸钙盐沉淀为主,厌氧消化液磷回收率及回收产物含磷率（以P2O5计）分别达到99.43%和38.49%;第一步磷回收后的上清液按一定的钙磷摩尔比投加到酸化后的厌氧消化液中进行第二步磷回收,当投加钙磷摩尔比为0.20时,在反应pH为9.0的条件下,回收产物同时含有磷酸钙盐和磷酸铵镁,厌氧消化液中氮、磷回收率分别达到13.19%和90.90%,回收产物氮、磷含量（以P2O5计）分别为0.26%和39.58%;经XRD、XRF、ICP及SEM等分析表征,2步磷回收的产物以磷酸钙盐和磷酸铵镁为主要成分,杂质少。研究表明,利用白云石为钙镁源,通过分别构建不同的磷回收体系可以分步从污泥厌氧消化液中经济有效地回收磷,且磷回收率和回收产物含磷率高。     

Nutrients removal and recovery by crystallization of magnesium ammonium phosphate from synthetic swine wastewater

With synthetic swine wastewater, lab-scale batch experiments were carried out to investigate the effects of pH value, magnesium dosage, calcium and carbonate concentrations on magnesium ammonium phosphate (MAP) crystallization. The morphology of the precipitates obtained was observed by using scanning electron microscopy with energy dispersive X-ray analysis, and the composition of the precipitates was analyzed with X-ray diffraction. The results show that the optimum pH value for MAP crystallization is in the range of 9.5-10.5; the phosphorus removal efficiency increases with the increase of Mg/P molar ratio; the optimum Mg/P molar ratio is 1.4, and excessive Mg dosage does not show significant effect on the efficiency improvement of MAP crystallization; the co-existing of Ca in solution disturbs the morphology and purity of the MAP product, and amorphous calcium phosphate will form when Ca increases to a certain concentration; CO3(2-) can affect the P removal efficiency, but does not obviously affect the morphology and purity of MAP.     

Ti（Ⅳ）催化臭氧／过氧化氢预处理酸性难降解废水

在Ti（Ⅳ）和过氧化氢存在条件下,考察了臭氧化酸性苯乙酮溶液、硝基苯溶液和垃圾渗滤液（浙江衢州某垃圾填埋场）的预处理效能。结果表明,在pH2．86条件下,单独臭氧化处理对苯乙酮、硝基苯和垃圾渗滤液的COD去除率分别为10．1％、44％和28．6％。BOD,／COD值分别从原来的0．039、0．060和0．085提高到了0．130、0．158和0．174,仍属生化难降解废水。当体系加入Ti（Ⅳ）后,臭氧化苯乙酮和硝基苯的COD去除率分别达到了75．5％和65％,BOD;／COD则提高到了0．679和0．314,可生化性提升明显。对于垃圾渗滤液,只有当体系加入Ti（Ⅳ）和H22后,臭氧化COD的去除率达到66．6％,BOD、／COD提高至0．425。上述结果对酸性难降解废水的处理实际意义非常突出。     

Combined chemical treatment of pharmaceutical effluents from medical ointment production

Three wastewater samples from a pharmaceutical plant formulating medical ointments were subjected to lab-scale treatment by a Fenton-like system in combination with lime coagulation. All samples were plant pre-treated by adsorption/flocculation/filtration processes with utilization of bentonite, but the quality of effluents did not comply with the regulations for wastewater discharged to local sewerage. The optimization of Fenton-like oxidation demonstrated the highest process efficacy at H(2)O(2)/COD weight ratio of 2:1, H(2)O(2)/Fe(2+) molar ratio of 10:1 and 2h of treatment time. The fast pH decrease to acidic values approximately 3 during first min of oxidation for all effluents suggested that pH adjustment was unnecessary. Combination of Fe(III) precipitation and lime coagulation proved feasible to improve considerably COD and residual iron concentration reduction in pharmaceutical effluents. Additionally, considerable BOD(7) reduction and BOD(7)/COD ratio improvement of pharmaceutical wastewater samples was achieved by combined treatment. The application of Fenton-like oxidation with subsequent iron (III)/lime coagulation did not only enhance the quality of pharmaceutical effluents with different chemical characteristics and help to meet the requirements for wastewater discharged to sewage, but also improve the biodegradability of pharmaceutical effluents.     

工艺条件对鸟粪石法回收磷耗碱量的影响及其理论计算

通过分析磷回收过程中存在的各种耗碱因素,推导出耗碱量的理论计算公式,计算出了不同工艺条件下的理论耗碱量,并与小型连续搅拌反应-沉淀磷回收过程的实验实测值进行比较。结果表明,耗碱量的理论计算值与实验测定值的平均相对误差为13.20%,说明计算方法可用于耗碱量的工程估算;耗碱量随出水pH值的增大而急剧增加,随废水中氨氮含量和磷初始浓度的增加都近似于线性增加,但随镁磷比的增加基本不变。因此,从节约废水处理成本的角度看,磷回收过程中pH值应控制在9.2-9.3,氮磷比控制在3.0-5.0,镁磷比控制在1.1-1.2为佳。磷回收过程的药剂消耗量与废水中磷的浓度和工艺条件有关,以磷初始浓度为124 mg/L,N/Mg/P=5∶1.2∶1,出水pH值为9.20的回收过程为例,处理毎吨废水需消耗片碱0.5313 kg,成本约为1.328元,需消耗氯化镁（含六个结晶水）0.9758 kg,成本约为0.634元。因此,处理每吨废水的药剂成本约为1.962元,其中耗碱约占67.7%。     

Phosphate recovery from greenhouse wastewater

A study was conducted to investigate the suitability of phosphate recovery from greenhouse wastewaters by using precipitation/crystallization process. More than 90% of the phosphate could be removed from the greenhouse wastewater. Various calcium phosphate salts were obtained in the process; hydroxyapatite [Ca5(PO4)3OH] could be the main product from the precipitates. Phosphate removal was affected by the presence of magnesium ion in wastewaters. An increase of magnesium concentrations in wastewaters decreased phosphate removal rates. The chemical contents of precipitates in terms of calcium, magnesium and phosphate were affected by calcium to magnesium molar ratio. Higher calcium contents were obtained at wastewaters with high calcium to magnesium molar ratio. An addition of magnesium did not affect the potassium contents in the precipitates. K-struvite, MgKPO4 x 6H2O, was not the major product in the precipitate, even with addition of a large quantity of magnesium.     

Calcite-seeded crystallization of calcium phosphate for phosphorus recovery

For phosphorus recovery from wastewater, the present paper aims at understanding the crystallization of calcium phosphate by using calcites (Juraperle and Coccolith) as seeds from hard water. Synthetic hard water with 60 mgCl(-1) carbonate and 10 mgPl(-1) phosphate was prepared and used in the batch experiments of calcite-seeded crystallization. The solution composition was measured throughout the batch crystallization process, and the corresponding saturation indices with respect to the minerals were calculated with PHREEQC Program. The surface of the calcite seeds was observed and measured with environmental scanning electron microscopy (ESEM), Fourier transform infrared (FTIR) and BET method. The studies show that both calcites are effective seeds for the crystallization of calcium phosphate from hard water; the used calcites are more efficient than the original ones because newly formed crystals with calcium phosphate have covered their surfaces. The studies show that the calcite seeds can be used for phosphorus recovery from hard waters.     

Phosphate Recovery from Greenhouse Wastewater

A study was conducted to investigate the suitability of phosphate recovery from greenhouse wastewaters by using precipitation/crystallization process. More than 90% of the phosphate could be removed from the greenhouse wastewater. Various calcium phosphate salts were obtained in the process; hydroxyapatite [Ca₅(PO₄)₃OH] could be the main product from the precipitates. Phosphate removal was affected by the presence of magnesium ion in wastewaters. An increase of magnesium concentrations in wastewaters decreased phosphate removal rates. The chemical contents of precipitates in terms of calcium, magnesium and phosphate were affected by calcium to magnesium molar ratio. Higher calcium contents were obtained at wastewaters with high calcium to magnesium molar ratio. An addition of magnesium did not affect the potassium contents in the precipitates. K‐struvite, MgKPO₄·6H₂O, was not the major product in the precipitate, even with addition of a large quantity of magnesium.     

Effects of solution conditions on the precipitation of phosphate for recovery. A thermodynamic evaluation

To understand the effects of solution conditions on the precipitation of calcium phosphates from wastewater for recovery, a computer programme PHREEQC was employed to calculate the speciation and saturation-index (SI) with respect to hydroxyapatite of a chemically defined precipitation system, which contains phosphate of 1–200 mg P/l, with Ca/P molar ratios of one to 10 times of the stoichiometric calcium to phosphorus molar ratio of hydroxyapatite, at a pH range of 7.0–11.0. The results show that the SI is respectively the logarithmic function of the phosphate concentration and the calcium concentration, increasing with the increase of either of them; the SI is a polynomial function of the solution pH value and increases with its increase, and the effect of solution pH value is due to its influence on base uptake of the precipitation reaction and the speciation of phosphate and calcium ions; the SI is also a logarithmic function of the solution ionic strength but decreases with its increase; at the temperature range of 5–30 °C the SI increases linearly with solution temperature and the effect of temperature is also due to its influence on the speciation of phosphate and calcium ions.     

改良型A2／O-MBR工艺的反硝化除磷性能研究

重点考察了-种改良型膜生物反应器（A2／O—MBR）的脱氮除磷性能。该工艺主要特点在于对膜池硝化回流液进行了固液分离,并将上清液和浓缩污泥分别回流至缺氧池和厌氧池,这种改进提高了系统对氮、磷的同步去除效率。实验结果表明,在水力停留时间（HRT）为12h,污泥龄（SRT）为30d,混合液回流比为200％的运行条件下,进水COD、NH4＋-N、TN和TP平均浓度分别为（225±38）、（24．8±3．9）、（26．7±2．9）和（2．90±0．53）mg／L时,增加膜池硝化回流液固液分离装置前后,系统对COD和NH4＋-N的去除都维持在较高水平,而系统对TN和TP的去除效果显著提高,出水TN和TP平均浓度分别由（14．9±3．3）mg／L和（1．95±0．72）mg／L下降到（9．4±1．9）mg／L和（0．91±0．38）mg／L,表明增加膜池硝化回流液固液分离装置显著改善了A2／O-MBR系统的脱氮除磷效果。反硝化除磷活性实验结果进一步表明,改进后系统中反硝化除磷活性占总除磷活性的比例由51．5％上升至61．7％,说明增加膜池硝化回流液固液分离装置强化了系统的反硝化除磷性能。     

VFAs、TOC及COD作为生物除磷能力指标的探讨

在实际生活污水的处理中,研究了通过A/O运行模式对生物除磷过程中磷的变化情况及在厌氧释磷过程中COD、TOC与VFAs变化之间的关系。结果表明,在厌氧释磷过程中VFAs的变化更能准确地反映系统内释磷进程,实际生活污水中能直接用于磷释放的有机物含量占COD的13.33%,并且释放1 mg P所需VFAs为1.401 mg,此值明显低于前期研究结果。通过对COD、TOC和VFAs 3种组分的分析,可将实际生活污水中的有机底物分为3类:易生物降解含碳有机物、难降解的含碳有机物和水中存在的无机性还原物质,含量分别占COD的13.33%、31.7%和54.97%,其中只有13.33%的含量对生物释磷有直接作用,并可对实际生活污水除磷有指导意义。     

Investigation on pretreatment of centrifugal mother liquid produced in the production of polyvinyl chloride by air-Fenton technique

Centrifugal mother liquid (CML) is one of the main sources of wastewater produced during the production of polyvinyl chloride in chlor-alkali industry. CML is a typical poorly biodegradable organic wastewater, containing many kinds of refractory pollutants. Specifically, it contains dissolved refractory polymers, especially polyvinyl alcohol (PVA), which can pass though the biotreatment processes and clog the membranes used for further treatment. In this study, to ensure the CML applicable to biotreatment and membrane treatment, a novel efficient and mild technique, air-Fenton treatment, was employed as a pretreatment technique to improve biodegradability of the CML and to break down the polymers in the CML. Firstly, the technique was optimized for the CML treatment by optimizing the main parameters, including the dosage of ferrous sulfate, initial pH of the wastewater, [H₂O₂]/[Fe²⁺], aeration rate, reaction time, and temperature, based on removal efficiency of COD and PVA from the CML. Then, the optimized technique was tested and evaluated. The results indicated that under the optimized conditions, the air-Fenton treatment could remove 66, 98, and 55 % of the COD, PVA, and TOC, respectively, from the CML. After the treatment, biodegradability of the wastewater increased significantly (BOD/COD increased from 0.31 to 0.68), and almost all of the PVA polymers were removed or broken down. Meanwhile, concentration of the remaining iron ions, which were added during the treatment, was also quite low (only 2.9 mg/L). Furthermore, most of the suspended materials and ammonia nitrogen, and some of the phosphorus in the wastewater were removed simultaneously.     

含吡啶有机废水物化预处理工艺

对含吡啶有机废水进行分类收集,分质处理,确定了蒸发脱盐-微电解-芬顿氧化预处理工艺路线。实验表明,蒸发脱盐阶段,pH值为5时,COD去除率达62.77%;微电解阶段,pH值为4、反应时间为2.5 h时,COD去除率达24.49%;Fenton试剂氧化阶段,pH值为4,30%H2O2投加量为3.5 ml/L,Fe2+与H2O2摩尔比为1∶20,反应时间为2.5 h时,COD去除率达30.41%。经预处理,废水B/C比从0.075上升至0.48,3种特征吡啶的去除率均达到95%以上。     

USSB反应器预处理聚酯生产废水

采用上流式分段污泥床（upflow staged sludge bed）反应器对聚酯废水进行了预处理试验研究.反应器内厌氧污泥经过近70 d的培养驯化后,用于处理聚酯废水.当进水COD值为800～2000 mg/L,HRT约为16～20 h时,其COD去除率基本能稳定在50%～55%之间;聚酯废水经预处理后,其BOD5/COD值由原来的0.3左右提高到约为0.6,取得了较好的预处理效果.但系统的总产气量由培养期的约13 L/d降至0.8 L/d左右,其中甲烷气体的含量也由50%下降至约6%.     

铁炭微电解深度处理焦化废水的研究

采用曝气铁炭微电解工艺对焦化废水进行了深度处理.结果表明,在活性炭、铁屑和NaCl投加量分别为10 g/L、30 g/L和200 mg/L的条件下反应240 min,出水COD去除率在30%～40%;酸性条件可以进一步提高COD去除率;微电解可以去除原生化出水中的难降解有机物,出水物质的分子量主要集中于2000 Da以下,以脂类和烃类化合物为主;出水的可生化性有了大幅度提高,BOD5/COD由0.08增加到0.53.实验结果表明,铁炭微电解是深度处理焦化废水的一种有效工艺.     

共存杂质对磷酸铵镁结晶法回收磷的影响研究

研究用磷酸铵镁（MAP）结晶法去除、回收废水中的磷,分析含磷废水中各类共存杂质对MAP法去除、回收磷的影响。结果表明,废水中无机钙离子的存在可提高磷的去除率,而大分子有机物杂质的存在会使磷的去除率显著降低,小分子有机物对磷的去除基本无影响。在反应体系中引入外来晶种烟煤、石英砂和铁屑可显著提高低浓度含磷废水磷的去除效率,其中娴煤作为晶种的效果最明显。     

臭氧氧化预处理难降解农药废水的研究

采用臭氧氧化技术预处理脲类农药生产废水,调节废水pH至弱碱,在此基础上考察废水臭氧氧化预处理的影响因素,得出最佳预处理条件：COD为200 mg/L,初始pH为11.3,臭氧投加量为14.2 mg/L。连续预处理180 min后,可生化性从0.12提高到0.58,说明该项技术可大大提高脲类农药废水的可生化性。     

水胺硫磷工业废水的酸性水解处理研究

水胺硫磷工业废水中 ,有机磷和硫化物含量均 >10 0 0 0mg/L ,COD高达 5 5 0 0 0mg/L左右 ,NH3 N在 4 0 0 0 0mg/L左右 ,BOD/COD仅为 0 .0 5 ,属典型难生物降解废水。本文采用常压酸性水解和脱氨除磷工艺处理该废水 ,有机磷、硫化物、NH3 N和总磷等去除率均 >90 % ,COD去除率达到 5 0 %以上 ,废水可生化性提高 ;同时 ,可回收得到硫氢化钠、氨水等物质 ,使废水资源得到了综合利用