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1.
The biodegradations of phenol and 4-chlorophenol (4-cp) were studied using the mutant strain CTM 2 obtained by the He-Ne laser irradiation on wild-type Candida tropicalis. The results showed that the capacity of the CTM 2 to biodegrade 4-cp was increased up to 400 mg•L-1 within 59.5 h. In the dual-substrate biodegradation, both velocity and capacity of the CTM 2 to degrade 4-cp increased with low-concentration phenol. A total of 400 mg•L-1 4-cp was completely degraded within 50.5 h in the presence of 300 mg•L-1 phenol. The maximum 4-cp biodegradation could reach 440 mg•L-1 with 120 mg•L-1 phenol. Low-concentration 4-cp caused great inhibition on the CTM 2 to degrade phenol. In addition, the kinetic behaviors were described using the kinetic model proposed in this lab.  相似文献   

2.
A novel bioactive foam emulsion bioreactor for benzene, toluene and xylene (BTX) contaminated air streams treatment has been developed. The gas-liquid interfacial area by biocompatible foam and driving force for mass transfer by a water immiscible organic phase were increased in this reactor. The effect of several parameters such as gas residence time, oxygen content, and organic phase concentration on bioreactor performance was studied. Experimental results showed an average elimination capacity (EC) of 220 g&;#8226;m-3&;#8226;h-1 with removal efficiency (RE) of 89.59% for BTX inlet concentration of 1 g&;#8226;m-3 at 15 s gas residence time in the bioreactor. The statistical developed model predicted that the maximum elimination capacity of the reactor for BTX could be reached to 423.45 g&;#8226;m-3&;#8226;h-1. Continues operation of the bioreactor with high EC and RE was demonstrated by optimizing the operational parameters of the bioreactor. Overall the results suggest that the bioreactor developed can be very effective systems to treat BTX vapors.  相似文献   

3.
复合生物反应器亚硝酸型同步硝化反硝化脱氮   总被引:5,自引:0,他引:5       下载免费PDF全文
Sequence hybrid biological reactor (SHBR) was proposed, and some key control parameters were investigated for nitrogen removal from wastewater by simultaneous nitrification and denitrification (SND) via nitrite. SND via nitrite was achieved in SHBR by controlling demand oxygen (DO) concentration. There was a programmed decrease of the DO from 2.50 mg·L^-1 to 0.30 mg·L^-1, and the average nitrite accumulation rate (NAR) was increased from 16.5% to 95.5% in 3 weeks. Subsequently, further increase in DO concentration to 1.50 mg·L^-1 did not destroy the partial nitrification to nitrite. The results showed that limited air flow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate. Nitrogen removal efficiency was increased with the increase in NAR, that is, NAR was increased from 60% to 90%, and total nitrogen removal efficiency was increased from 68% to 85%. The SHBR could tolerate high organic loading rate (OLR), COD and ammonia-nitrogen removal efficiency were greater than 92% and 93.5%, respectively,, and it even operated under low DO concentration (0.5 mg·L^-1) and maintained high OLR (4.0 kg COD·m^-3·d^-1). The presence of biofilm positively affected the activated sludge settling capability, and sludge volume index (SVI) of activated sludge in SHBR never hit more than 90 ml·L^-1 throughout the experiments.  相似文献   

4.
Pervaporation has attracted considerable interest owing to its potential application in recovering biobutanol from biomass acetone-butanol-ethanol (ABE) fermentation broth. In this study, butanol was recovered from its aqueous solution using a polydimethylsiloxane (PDMS)/ceramic composite pervaporation membrane. The effects of operating temperature, feed concentration, feed flow rate and operating time on the membrane pervaporation per-formance were investigated. It was found that with the increase of temperature or butanol concentration in the feed, the total flux through the membrane increased while the separation factor decreased slightly. As the feed flow rate increased, the total flux increased gradually while the separation factor changed little. At 40 C and 1% (by mass) butanol in the feed, the total flux and separation factor of the membrane reached 457.4 g•m2•h1 and 26.1, respec-tively. The membrane with high flux is suitable for recovering butanol from ABE fermentation broth.  相似文献   

5.
煤气废水酸化破乳预处理功效探讨   总被引:1,自引:0,他引:1  
General pretreatment processes of ammonia stripping and phenols solvent extraction can reduce the concentration of toxic compounds of the coal gasification wastewater for the following biological treatment. However, some emulsified coal tar still exists in the influent and many substances in coal tar are refractory and toxic to microorganisms. This study is mainly on the removal of emulsified coal tar by acidification demulsion. The experimental results show that the acidification process of the wastewater by pure hydrochloric acid can reduce the chemical oxygen demand (COD), total organic carbon (TOC), total phenolics and oil about 3.1%-11.3%, 6%-- 10.8%, 5.3%--8.6% and 25.2%--57.4% respectively with pH value in the range of 4 to 7. The analysis of molecular weight distribution indicates that compounds removed from the wastewater by this process are large molecular substances. The experiment also shows that the efficiency of COD removal in the demulsion process by different acids is different and the phosphoric acid is prominent. The preserved time of the wastewater also affects the efficiency of demulsion. Small amount low-cost solid additives including kaolin and diatomite can improve the rate of coal tar sedimentation and enhance the removal efficiency of organics in the phosphoric acidification process.  相似文献   

6.
A strain isolated from the fruiting body of a fungus parasitized on Elaphomyces was identified as Cordyceps ophioglossoides based on the morphological characteristics and the analysis of ITS-5.8s rDNA sequence. The optimal medium composition (g•L-1), containing sucrose 66.0, yeast powder 10.0, silkworm chrysalises digest 30.0, MgSO4•7H2O 0.4, and KH2PO4 0.4, was found using fractional factorial design and a central composite design, and the optimization of cultural conditions obtained a result of seed age 6 days, inoculum size 6% (by volume), initial pH 5.6, temperature 24°C, shaking speed 160 r•min-1 by one-factor-at-a-time method. The maximum biomass reached about 20.2 g•L-1 after 90 hours culture under the optimal conditions. Elementary pharmacological activities showed that mycelia of C. ophioglossoides L2 from submerged culture promoted uterus growth in estrogen- depleted mice. In the 15-litre scale-up fermentation, the mycelial biomass was around 19.1 g•L-1, indicating a promising prospect for this biotechnology and the potency to develop its medical value.  相似文献   

7.
Considering limited success in target-hitting discharge from alcohol industry, our attention was directed toward a recycling use of distillery spentwash (DS) in cassava bioethanol production by using a two-stage up-flow anaerobic sludge blanket bioremediation (TS-UASBB). With the TS-UASBB, , COD, N and P in the effluent from the DS degraded significantly and their concentrations were kept at 0.2 g•L1, 2.0 g•L1, 1.0 g•L1 and 15 mg•L1, respectively, in 13 batch processes for water-recycled ethanol fermentation. With the effluent used directly as dilution water, no heat-resistant bacteria were found alive. The thirteen-batch ethanol production individually achieved 10% after 48 h fermentation. The starch utilization ratio and total sugar consumption were 90% and 99.5%, respectively. The novel water-recycled bioethanol production process with ethanol fermentation and TS-UASBB has a considerable potential in other starchy and cellulosic ethanol production.  相似文献   

8.
A neutral metalloprotease was purified from the cultured mycelia of Laccocephalum mylittae, an effective medicinal fungus widely used in anthelmintic therapy. The protease was purified to homogeneity with 31.85-fold purification and a final yield of 21.76%. The subunit molecular weight of the protease is about 40000 estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The optimum reaction pH and temperature are 7.5 and 50ºC, respectively. The protease activity is largely enhanced by Ca2+, but highly inhibited by tetrasodium ethylenediaminetetraacetate (EDTA), a metal-chelator, suggesting that the enzyme is a metalloprotease. The Michaelis-Menten constan Km and Vmax value for casein substrate are 6.09 mg&;#8226;ml-1 and 21.32 μg&;#8226;min-1&;#8226;ml-1, respectively. In vitro anthelmintic tests of the protease exhibit distinct lethal effects on the third stage larvae (L3) of Ascaris suum. Scanning electron microscopy and SDS-PAGE analysis indicates that the proteolysis of larvae proteins caused by this protease may relate to the anthelmintic activity of L. mylittae.  相似文献   

9.
The adsorption and mechanism of Re(VII) on resin D318 were studied using chemical methods and IR spectrometry. At pH 5.2, the static and dynamic saturation adsorption capacities were 351.4 and 366.5 mg&;#8226;g&;#61485;1, respectively. The adsorption behavior obeyed the Freundlich empirical equation and the adsorption rate constant k298 was 6.37×10&;#61485;4 s&;#61485;1. The desorption percentage was up to 99.7% when 2.0 mol&;#8226;L&;#61485;1 KSCN was used for dynamic desorption.  相似文献   

10.
刺芹侧耳多功能过氧化物酶的纯化与鉴定   总被引:1,自引:1,他引:0       下载免费PDF全文
A versatile peroxidase (VP-Peco60-7) was generated and purified from the liquid culture of Pleurotus eryngii. The purification procedure included ammonium sulfate precipitation, ion exchange chromatography, and gel chromatography. The molecular weight and isoelectric point (pI) of VP-Peco60-7 were determined to be approximately 40 kDa and 4.1, respectively. By N-terminal sequence determination and peptide mapping analysis, VP-Peco60-7 was found to be similar to the versatile peroxidase isoenzyme VPL1, which was previously isolated from liquid cultures of the same species. However, the molecular weight and pI of VP-Peco60-7 were different from those of versatile peroxidases of liquid cultures, implying that the VP-Peco60-7 in this study is of a novel type. With 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) as a substrate, the maximal enzyme activity was obtained at 50 °C and pH 3.0. The catalysis of ABTS by VP-Peco60-7 was expressed by the Michaelis-Menten equation. At 50 °C and pH 3.0, the maxi-mum velocity (Vmax) was 188.68 U•mg1 and the michaelis constant (Km) was 203.09 mmol•L1.  相似文献   

11.
生物质炭吸附及其与O3耦合处理生物质废水   总被引:1,自引:0,他引:1  
针对我国生物质废水污染问题,建立生物质炭吸附、生物质炭/O3耦合处理生物质废水的工艺,并与O3氧化工艺比较。生物质炭吸附处理生物质废水的工艺中,研究了生物质炭吸附生物质废水中的有机物的吸附平衡曲线,考察了吸附时间、生物质炭投加量、不同炭种对COD脱除率的影响。生物质炭吸附生物质废水中的有机物的吸附平衡曲线符合Langmuir方程,吸附平衡常数为8.833×10-5 L/mg,饱和吸附容量为1.136×106 mg/g;20℃下,生物质炭的投加量为20g/100mL废水,吸附15min,废水相COD值可从12496mg/L降至761mg/L,有机物脱除率可达93.9%。单独O3降解及先O3降解后生物质炭吸附的两步法工艺不适合生物质废水的处理,生物质炭/O3协同的一锅法处理废水效果最佳,在生物质用量仅为1g/100mL废水,臭氧流速为150mL/min,处理时间20min时,COD脱除率高于90%。  相似文献   

12.
为解决现有SBR工艺的容积交换率低、运行稳定性不足等问题,提出了基于污泥转移的SBR工艺,介绍了基于污泥转移SBR工艺的基本概念和原理,研究了在推荐工况下的除污性能。结果表明,该工艺对COD的平均去除率>80%,出水COD稳定在45 mg.L-1左右。出水NH4+-N、TN随进质量水浓度的增加而增加,但平均去除率分别稳定在94%和64%。磷酸盐的平均去除率为96%,出水磷酸盐质量浓度稳定在0.3 mg.L-1以下。  相似文献   

13.
《分离科学与技术》2012,47(7):999-1007
The objectives are to evaluate the feasibility of treating oily wastewater using synthetic polymers (polyaluminum chloride (PAC), polyferric sulfate (PFS), and polyacrylamide (PAM)) combined with natural diatomite and to refine the operating parameters using diatomite as an adsorbent and a coagulant aid. The enhanced coagulation/flocculation by combining PAC with diatomite was investigated through mechanism analysis compared to the combination of PFS/PAM with diatomite, respectively. The effects of coagulant dose, initial pH, and settling time on chemical oxygen demand (COD) and turbidity were studied using PAC-diatomite in comparison with using PAC only. The enhanced coagulation/flocculation of diatomite with PAC was better than that with PFS/PAM in terms of COD/turbidity removal and floc settling characteristics, considering costs. The PAC-diatomite system reduced more than 70% of COD and 90% of turbidity over a wide pH range (7–10) within 20 min, with the optimum dose of PAC 50 mg/l and diatomite 1250 mg/l. The added diatomite effectively saved over 85% of PAC dose and simultaneously increased over 50% of COD removal efficiency. This study provided a novel and economical approach for diatomite utilization in the treatment of oily wastewater, satisfying the demands of reuse or reinjection into the ground.  相似文献   

14.
王淮  孙玉栋  郦豪 《广州化工》2012,40(13):133-134,150
通过对保险粉废水进行化学氧化处理研究,为解决保险粉废水处理提供了参考。研究结果表明:经浓硫酸调节pH后,先经100 g.L-1CaCl2絮凝处理1 h,后用50 mL.L-1H2O2氧化处理3 h,保险粉废水COD(Chemical Oxygen Demand)从204620 mg.L-1降到123233 mg.L-1,其去除率达到39.8%,盐度去除率达到48.3%。  相似文献   

15.
王曼  李冬  张杰 《水处理技术》2012,38(1):51-54
为研究生物接触氧化技术处理河道污水的能力,实验室采用砾石和火山岩填料作为微生物载体,并利用稀释后的生活污水模拟河道污水。通过调控反应器的运行方式和运行条件来降低出水COD和TN的质量浓度,实现同时去除有机物和TN的目的。结果表明,在温度为12.8~24℃和DO质量浓度为2.9~6.3 mg.L-1的条件下,当进水COD为80~150 mg.L-1、TN质量浓度为25~55 mg.L-1、水力负荷为5~7 m3.m-3.d-1的条件下,采用分段进水前后的COD平均去除率均维持在75%,出水COD均小于50 mg.L-1,TN的平均去除率由分段进水前的40%提高到70%,且TN质量浓度降低至15 mg.L-1,均达到污水综合排放标准(GB 8798-1996)中的一级A标准,说明接触氧化工艺能同时有效的去除COD为代表的有机物和TN。  相似文献   

16.
采用水解酸化+CASS工艺处理制革园区工业废水。调试运行结果表明,在进水COD和氨氮平均质量浓度分别为607、50.7 mg.L-1时,出水COD和氨氮平均浓度分别为70、5 mg.L-1,平均去除率分别达88.5%和90.1%。出水水质达到污水综合排放一级标准(GB8 978-1996)。  相似文献   

17.
采用厌氧折流板(ABR)-生物接触氧化(BCO)工艺处理新兴农村生活污水,试验研究了COD去除率、pH、挥发性脂肪酸(VFA)、碱度等随水力停留时间(HRT)的变化情况以及BCO中氮的转化。试验停留时间经过20、16、12、8、4、3、2 h的连续改变,最终确定最佳停留时间是4 h。试验进水COD平均为1 530 mg.L-1,经过ABR处理之后,出水COD降为119 mg.L-1,经过BCO工艺处理后,COD降为9 mg.L-1。ABR工艺COD的平均去除率为92%,总COD去除率为98%。同时,进水NH4+-N经过ABR-BCO工艺处理以后,平均质量浓度由93 mg.L-1降为0.52 mg.L-1,NH4+-N去除率为99%,总氮去除率在40%左右。  相似文献   

18.
利用剩余污泥水解酸化液作为外加碳源研究中部曝气和底部曝气曝气生物滤池(BAF)处理低碳氮比生活污水时的生物脱氮性能。结果表明,碳源与污水投配的流量比以及是否回流对BAF生物脱氮效果影响明显,气水流量比和回流流量比对BAF生物脱氮效果有一定影响;进水NH4+-N、TN质量浓度和COD分别为43.11、45.07、29.2mg.L-1时,中部曝气BAF的NH4+-N和TN去除率分别为99.04%和78.32%,出水COD为32.4 mg.L-1;底部曝气BAF的NH4+-N和TN去除率分别为98.61%和68.99%,出水COD为28.4 mg.L-1。研究表明,BAF在2种运行方式下可获得良好的硝化与反硝化性能,且不会引起二次污染。  相似文献   

19.
以贵阳市城市污水为研究对象,采用MBR脱氮除磷工艺进行了140 d的中试试验。试验结果表明,在无外加碳源的情况下,系统对COD、TN、NH4+-N、TP的去除率分别达到91.9%、78%、99.8%、89%,平均出水分别在26.41、11.8、0.27、0.49 mg.L-1;试验结束时对剩余污泥进行了序批式试验,表明系统中DPAOs/PAOs在39.7%左右,DPAOs的富集强化了系统的除磷效果。出水中的SS质量浓度、浊度及大肠杆菌数量分别小于4 mg.L-1、3 NTU、2个,达到城市杂用水的回用标准。定期采用体积分数0.5%的NaClO药洗有效地抑制了膜的污染,保证了产水的稳定性。  相似文献   

20.
为了研究铁元素对A2O工艺污泥絮凝性的影响,考察Fe3+在污泥上清液、胞外聚合物(extracellular polymeric substances,EPS)与底泥(Pellet)中的分布和迁移转化规律,结合三维荧光光谱(3D-EEM)、原子吸收和X射线衍射仪(XRD)分析Fe的存在形态和结构特征,揭示Fe3+与微生物代谢产物的作用机制,探索Fe3+对脱氮除磷效率的影响。结果表明:低浓度Fe3+(<10 mg·L-1)能够提高COD和TN去除率,促进微生物活性,增强污泥生物絮凝性;高浓度Fe3+(10~40 mg·L-1)则抑制微生物活性,使EPS总量升高,污泥絮体脱稳,LB、TB层PN/PS是影响污泥絮凝性的关键因素;Fe3+的投加强化生物除磷效率,当Fe3+浓度为40 mg·L-1时,TP去除率为93%。Fe3+在污泥混合液中的分布规律为TB>上清液>LB>SMP,Fe3+在生物体内富集累积,能够改变EPS各层的组分。  相似文献   

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