非均相催化臭氧处理煤化工生化出水

煤化工生化出水属于有毒害和难以生物降解的工业废水,为此,采用非均相催化臭氧氧化技术深度处理煤化工生化出水,以负载过渡金属铜和锰的活性炭作为催化剂提高臭氧降解污染物能力．结果表明:该处理对COD和氨氮去除率达60％~72％和30％~35％,处理后出水COD和氨氮平均质量浓度低于60和15 mg／L,显著高于单独臭氧氧化,达到GB18918—2002水污染排放一级B标准;在酸性条件下,催化剂活性受到限制,碱性条件对其具有促进作用. 与单独臭氧氧化相比,催化剂的使用均提高了臭氧对污染物的降解能力;处理后出水的可生化性得到显著提高,不会对受纳水体产生二次污染．     

外循环厌氧工艺处理鲁奇煤制气废水的研究

为了提高煤制气废水的厌氧处理能力,研究了实际工程中煤制气废水的外循环厌氧处理效果,并考察进水质量浓度、水力停留时间和投加甲醇对煤制气废水处理效能的影响.结果表明:煤制气废水的厌氧处理效率很低,进水COD和总酚质量浓度分别为1100mg/L和210mg/L时去除率分别为18.5%和20.3%,当进水COD质量浓度提高至2100mg/L时去除率分别为15.2%和25.5%.水力停留时间由24h延长至48h,COD和总酚去除率略有提高.投加甲醇控制COD含量为200～500mg/L,COD和总酚去除率分别提高至40.7%和35.2%.投加甲醇基质可以明显提高废水的厌氧处理效能,稀释作用或者延长水力停留时间的效果甚微.     

多相催化氧化法处理酚氰废水的研究

以γ-Al2O3为载体，采用浸渍法制备了CuO，MnO2及MnO2/K2O等3种负载型催化剂，以臭氧为氧化剂，采用多相催化氧化法，处理煤制气厂和焦化厂的含酚氰废水，结果表明：这3种催化剂能显著地提高酚和氰的去除速率和去除率，其中MnO2/K2O催化剂对含酚300mg/L，含氰50mg/L的酚氰废水的氧化速度提高了3～5倍，酚和氰的去除率大于90%，COD去除率大于80%。     

非均相流化床式催化氧化处理脱硫废水的工艺

非均相流化床式催化氧化工艺可以充分降解脱硫废水中的有机物,对其的研究可为脱硫废水达标排放和零排放工艺的建立提供技术参考。文章采用煅烧方式制备了高效固体催化剂,建立了以臭氧为氧化剂的流化床高级氧化工艺,对三联箱处理后的脱硫废水进行深度处理以降低COD、氨氮和悬浮物。结果表明:在催化剂投加量为10 g/L、臭氧通入时间为2 h、曝气量为10 h/L的条件下,实现了脱硫废水的COD由650 mg/L降低至210 mg/L,氨氮指标由315.7 mg/L降低至35 mg/L,悬浮物指标由5 500 mg/L降低至1 400 mg/L;在反复利用过程中,催化剂可保持优异的稳定性。     

非均相催化臭氧氧化深度处理炼油废水

采用非均相催化臭氧氧化工艺(自主研制的铜锰氧化物催化剂)处理炼油废水,探索该工艺深度处理炼油废水的不同影响因素和机制,获得最适宜工艺参数,使处理出水满足炼油企业的回用水标准.考察反应前后催化剂的稳定性.废水取自广东某炼油企业.结果表明:最优值为原始pH=6.8,臭氧投加质量浓度为50mg/L,催化剂质量浓度为3.0g/L.在17℃室温条件下反应15min,出水化学需氧量(COD)满足该炼油企业的回用水标准:COD<50mg/L.氨氮有一定的去除.使用前后,催化剂的抗压性能和活性组分未发生明显变化,催化效果稳定.GC-MS分析结果表明:非均相催化氧化工艺可以减少炼油废水中的大分子有机物质,尤其是含氮的杂环物质,能将高沸点大分子有机物降解为低沸点小分子有机物质,提高炼油废水的可生化性.     

非均相催化臭氧氧化深度处理委内瑞拉超重原油废水

采用非均相催化臭氧氧化工艺(自主研制的铜锰氧化物催化剂)处理重油废水,探索该工艺深度处理重油废水的不同影响因素和机制,获得最适宜工艺参数,使处理出水满足炼油企业的回用水标准.同时考察了反应前后催化剂的稳定性.废水取自广东某炼油企业.结果表明:最优值为原始pH=6.8,臭氧投加量50mg/L,催化剂3g/L.在室温条件下(17℃)反应15min,出水化学需氧量(COD)满足该炼油企业的回用水标准:COD<50mg/L.氨氮也有一定的去除.使用前后,催化剂的抗压性能和活性组分未发生明显变化,催化效果稳定.GC-MS分析结果表明:非均相催化氧化工艺可以减少废水中的大分子有机物质,尤其是含氮的杂环物质,能将高沸点大分子有机物降解为低沸点小分子有机物质,提高废水的可生化性.     

臭氧协同催化剂处理炼油废水实验研究

利用臭氧催化氧化技术,开展降解炼油废水的实验研究。通过模拟活性污泥法验证污水生物降解性能的调控效果。结果表明:利用臭氧非均相催化技术可有效降解炼油废水中有机污染物且生物降解性能显著提高,COD平均去除率达65.0%,BOD5/COD从0.13提高至0.28;对于本实验装置,处理4 000mL炼油废水最佳反应条件为臭氧流量40L/h,催化剂为200cm3载铜活性炭,pH=11,反应时间40min。     

二氧化锰催化二氧化氯氧化处理萘酚绿模拟废水的实验研究

研究了二氧化氯直接氧化和催化氧化处理萘酚绿模拟废水.二氧化氯化学氧化处理COD为1533mg/L的萘酚绿废水,在最佳pH值为1.2,二氧化氯投加量为1500 mg/L,反应时间60 min条件下,COD去除率和脱色率分别为45.3%和92.5%.在最佳pH值1.2,经过1000 mg/L二氧化氯和5 g MnO2-SiO2催化剂催化氧化30 min后,COD去除率和脱色率分别为70.9%和96.8%.BOD5/CODcr由原废水的0.22提高至0.71,可生化性得到提高,为难降解废水的后续处理创造了条件.催化剂可循环使用9次而不失去活性.经红外光谱分析,催化剂有效成份二氧化锰与硅胶载体之间是以化学键的形式相连,不是简单的机械混合.     

二氧化锰催化二氧化氯氧化处理萘酚绿模拟废水的实验研究

研究了二氧化氯直接氧化和催化氧化处理萘酚绿模拟废水.二氧化氯化学氧化处理COD为1533mg/L的萘酚绿废水,在最佳pH值为1.2,二氧化氯投加量为1500mg/L,反应时间60min条件下,COD去除率和脱色率分别为45.3%和 92.5%.在最佳pH值1.2,经过1000mg/L二氧化氯和5g MnO2-SiO2催化剂催化氧化30min后,COD去除率和脱色率分别为70.9%和96.8%.BOD5/CODcr由原废水的0.22提高至0.71,可生化性得到提高,为难降解废水的后续处理创造了条件.催化剂可循环使用9次而不失去活性.经红外光谱分析,催化剂有效成份二氧化锰与硅胶载体之间是以化学键的形式相连,不是简单的机械混合.     

O3/Na2S2O8耦合体系处理垃圾渗滤液生化出水

为提高垃圾渗滤液生化出水的化学需氧量(chemical oxygen demand,COD)、色度以及氨氮的去除效率,在不同的臭氧通气量、过硫酸钠投加量、pH、反应时间等反应条件下,研究了臭氧过硫酸盐耦合体系对于垃圾渗滤液生化出水的氧化效果.实验结果表明:COD、色度和氨氮的去除率随着过硫酸盐、臭氧通气量、反应时间的增加而增大,并且溶液pH为10的环境更有利于用臭氧过硫酸盐体系氧化降解污染物,在臭氧通气量为0.8 g/h、过硫酸钠投加量为10 g/L、pH为10、反应时间为200 min的条件下,废水的COD、色度和氨氮的去除率分别达76.3%、92.0%和55.4%.相较于单一过硫酸盐氧化方式,在过硫酸盐氧化过程中加入臭氧,处理效果显著提高,臭氧氧化与过硫酸钠氧化产生了一定的协同效应.     

A Pilot-scale Study on Coal Gasification Wastewater Reclamation Using Pretreatment Alternatives Combined with Ultrafiltration and Reverse Osmosis

Aims to investigate the performance of the pilot-scale reclamation plant for coal gasification wastewater (CGW) using ultrafiltration and reverse osmosis with appropriate pretreatment alternatives, different pre-treatment alternatives- coagulation, adsorption, and ozonation methods were employed to treat the secondary effluent of coal gasification wastewater (SECGW) in a pilot-scale pressurized membrane system. The performance was compared to choose the most suitable pre-treatment alternative for the SECGW reclamation. Ozone reaction achieved highest COD removal efficiency (79.6%-91.0%), resulting in the stable normalized parameters of the subsequent ultrafiltration and reverse osmoses. In contrast, the coagulation and adsorption processes achieved only 32.8%-45.7% and 53.1%-64.6% decreases in COD, respectively. The residual organic pollutants in the reverse osmosis feed water led to an increase in normalized pressure drop and a decrease in normalized permeability (or membrane transference coefficient). The hydrophobic fraction was the main constituent (approx. 70% of DOC) in pretreated SECGW, and the hydrophobic-neutral fraction contributed mostly to the UV absorbance (53%). Fluorescence excitation emission matrices revealed that ozonation removed most of the hydrophobic and aromatic proteins such as tyrosine and tryptophan which dominated in raw wastewater. The recalcitrant compounds such as phenolic compounds, heterocyclic compounds, especially long-chain hydrocarbons, which were easily attached to the membrane surface and contributed to organic fouling, could be oxidized and mineralized by ozone. Among the three pretreatments, ozonation showed highest removal efficiencies of hydrophobic and aromatic proteins, therefore resulting in highest normalized permeability.     

Performance of the Full-scale Loop Hybrid Reactor Treating Coal[KH-*1] Gasification Wastewater under Different Recirculation Modes

This paper aims to investigate the simultaneous removal efficiencies of both COD and nitrogen in a single reactor treating coal gasification wastewater (CGW). A novel loop hybrid reactor was developed and operated under different recirculation modes in order to achieve simultaneous removal of refractory compounds and total nitrogen (TN) in a full-scale CGW treatment plant. Mid-ditch recirculation was superior to other operational modes in terms of the NH₃-N and TN removal, resulting in a TN removal efficiency of 52.3%. Although the system achieved equal COD removal rates under different recirculation modes, hydrophobic acid (HPO-A) fraction of effluent dissolved organic matter (DOMef) in mid-ditch recirculation mode accounted for 35.7%, compared to the proportions of 59.2%, 45.3% and 39.4% for the other modes. The ultraviolet absorbance to dissolved organic carbon ratio test revealed that effluent under mid-ditch recirculation mode contained more non-aromatic hydrophilic components. Furthermore, appropriate recirculation and anoxic/oxic (A/O) partitions were also demonstrated to remove some refractory metabolites (phenols, alkanes, aniline, etc.), which reduced the chromaticity and improved the biodegradability.     

Three controllable factors of steady operation of EGSB reactor

The bench-scale EGSB (expanded granular sludge bed) reactor was operated to study the effect of sludge loading rate, pH value and nutrient element on the operation of the EGSB reactor and the control rule of these factors. Continuous flow was used to treat synthetic wastewater containing dextrose and beer, and the temperature of reactor was controlled at mesophiles temperature (33 ℃). The experimental results demonstrated that the proper sludge loading rate was 0.9-1.42 kg COD/(kg VSS·d); the pH value in the reactor was controlled by adding sodium bicarbonate, the proper additive quantity was 1000-1200 mg/L; the additive quantity of nutrient element was as follows: 41.3 mg/(SS·d) of FeCl2·4H2O, 4.3 mg/(SS·d) of CoCl2·6H2O, 8.2 mg/(SS·d) of NiCl2·6H2O, 7.5-13 mg/(SS·d) of CaCO3,and 56.7-22.7 mg/(SS·d) of 7Na2S·9H2O, respectively. When these parameters were properly determined, the EGSB reactor could treat wastewater with 400-5000 mg/L COD concentration. The COD removal efficiency was over 85%. The operation of the EGSB reactor was steady and the EGSB reactor had strong anti-shock load ability.     

Degradation of Phenolic Compounds in Coal Gasification Wastewater by Biofilm Reactor with Isolated Klebsiella sp.

This study was conducted to evaluate the degradation of phenolic compounds by one strain isolated from coal gasification wastewater（ CGW）. 16S rRNA gene sequences homology and phylogenetic analysis showed that the isolate is belonged to the genus Klebsiella sp. The effect of different phenolic compounds on the isolate was investigated by determining OD600and phenoloxidase activity,of which the results showed that the isolate can utilize phenol,4-methyl phenol,3,5-dimethyl phenol and resorcinol as carbon resources. The biofilm reactor（ formed by the isolate） can resist the influent concentration of phenolic compounds as high as750 mg /L when fed with synthetic CGW and incubated at optimum conditions. The capacity of improving the biodegradability of CGW through degrading phenolic compounds was testified with fed the biofilm reactor with real CGW. Thus,it might be an effective strain for bioaugmentation of CGW treatment.     

Experimental study on zero excess sludge production process with ozonation unit in MBR process

In order to investigate the influence factors of zero excess activated sludge (EAS) process by ozonation, a 100 L membrane bioreactor coupled with a sludge ozonation unit (MBR-SO) was performed for 80 d without EAS wasting. Some mathematical models were developed to elucidate the relationship between process parameters and the operating effects. It is considered that the sludge lysing ratio (ξ), produced COD per unit mass lysed MLSS (η), observed sludge yield coefficient (Yobs) and intrinsic yield coefficient for COD produced by lysed sludge (Y2) significantly affect the flowrate to ozonation unit (q). When q is 0.0067 times of influent flowrate (Q) and ξ is about 0.72 for each batch ozonation, a relatively stable MLSS concentration of 8168 mg/L and zero Yobs are achieved in the MBR-SO system. The calculation of sludge disintegration number indicates that the high ξ can apparently decrease the sludge amount needed for ozonation. At the same ozone dose, the low input ozone concentration and high flowrate can enhance the sludge lysing effects and a low energy consumption of 0.041 Yuan/m3 wastewater is obtained.     

Sludge ozonation and its effect on performance of submerged membrane bio-reactor

To investigate the effects of ozonation on minimizing the excess sludge and enhancing the nitrogen removal in an effluent,batch and continuous experiments in two MBRs with and without sludge ozonation (namely combined and reference run) were carried out. Through ozonation at a dose of 0.16 mg O3/mg MLVSS,53.1% of the treated MLVSS was solubilized,and soluble SCOD/TN ratio of ozonized sludge (OS) was about 8.6 due to the release of cellular nitrogen-contained materials and SCOD loss by ozone mineralization. In addition,the results of batch nitrification and denitrification tests with OS supernatant indicated that solubilized sludge could act as a reducing power for denitrification and a nitrogen source for nitrification. 40-day operation of two MBR systems demonstrated that the recirculation of OS into a bioreactor enabled the combined system have two advantages over the control one. The observed sludge yield (Yobs) was decreased from 0.13 to 0.06g MLSS/g COD,while the nitrogen removal was increased from 64.6% to 72.3%. And sludge ozonation elevated the inorganic fraction of MLSS,but did not impact sludge activities.     

SBBR法处理高盐废水

通过逐步提高盐度的方法驯化出耐高盐的活性污泥,采用序批式生物膜法(SBBR)进行模拟高盐废水的处理试验,对盐度为0和2%,COD为300 mg/L的高盐废水进行研究。结果表明,在每周期12 h、曝气量0.6 L/min、平均污泥质量浓度2 000~3 500 mg/L、污泥龄为18 d条件下,出水COD去除率变化不大,分别为97%和93%,而相应的出水NH4+-N去除率从93%降低到72%,表明废水盐度增大,对系统的硝化能力有较大影响。改变进水有机负荷对出水COD去除影响不大,该系统耐有机负荷冲击能力较强。     

Performance of the Full-scale Loop Hybrid Reactor Treating Coal Gasification Wastewater under Different Recirculation Modes

This paper aims to investigate the simultaneous removal efficiencies of both COD and nitrogen in a single reactor treating coal gasification wastewater( CGW). A novel loop hybrid reactor was developed and operated under different recirculation modes in order to achieve simultaneous removal of refractory compounds and total nitrogen( TN) in a full-scale CGW treatment plant. Mid-ditch recirculation was superior to other operational modes in terms of the NH3-N and TN removal,resulting in a TN removal efficiency of 52. 3%.Although the system achieved equal COD removal rates under different recirculation modes,hydrophobic acid( HPO-A) fraction of effluent dissolved organic matter( DOMef) in mid-ditch recirculation mode accounted for35.7%,compared to the proportions of 59. 2%,45. 3% and 39. 4% for the other modes. The ultraviolet absorbance to dissolved organic carbon ratio test revealed that effluent under mid-ditch recirculation mode contained more non-aromatic hydrophilic components. Furthermore,appropriate recirculation and anoxic / oxic( A/O) partitions were also demonstrated to remove some refractory metabolites( phenols,alkanes,aniline,etc.),which reduced the chromaticity and improved the biodegradability.     

Effects of different acclimations on high solution bacteria in coal-gas wastewater degradation

To make microbial community be applied more easily in practical biotreatment engineering,three acclimation processes were carried out in lab scale. Three kinds of mixed microorganism cultures with degradability for a gas-making plant wastewater were obtained. The degradation experiments results of coal-gas wastewater indicated that different acclimation processes had obviously impacted on degradability of microbial community,and under high sludge loading rate,mixed microorganism cultureⅠ(obtained by H.S.B as bacteria source and raw wastewater as alone carbon and energy source)presented stronger degradability for coal gasification wastewater than the others. COD removal rate of mixed cultureⅠcan reach 57.6% under very low MLSS when the influent COD is 900 mg/L. Meanwhile,the results of microscopic examination showed that Protozoa,mainly epistylis and Vorticella species,were stronger activity and larger quantities in mixed cultureⅠ.