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500t/h污水处理场开车总结及几点建议 总被引:2,自引:0,他引:2
介绍了胜利石化总厂500t/h污水处理场的流程,总结了开车后遇到的问题、采取的措施及取得的效果,并结合本厂实际提出了改进意见。 相似文献
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Fed-batch cultures of recombinantEscherichia coli strains were carried out for the production of poly(3-hydroxybutyric acid) (PHB) in a chemically defined medium. TheE. coli strains used were XL1-Blue, harboring pSYL105, a stable high-copy number plasmid containing theAlcaligenes eutrophus polyhydroxyalkanoate (PHA) genes, and XL1-Blue, harboring pSYL107, which is pSYL105 containing theE. coli ftsZ gene to suppress filamentation. With XL1-Blue(pSYL105) the final cell mass and PHB concentration obtained in 62 h were 102 and 22.5 g/L, respectively. Fed-batch culture of XL1-Blue(pSYL107) under identical conditions resulted in a final cell mass and PHB concentration of 127.5 and 48.2 g/L, respectively. The PHB contents obtained with XL1-Blue(pSYL105) and XL1-Blue(pSYL107) were 22.1 and 37.8%, respectively. Therefore, PHB was more efficiently produced in a defined medium by employing filamentation-suppressed recombinantE. coli. 相似文献
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催化湿式氧化法处理吡虫啉农药废水 总被引:2,自引:0,他引:2
自制了Cu/Mn,Cu/Ce,Cu/Ni,Ce/Mn,Ce/Ag等催化剂,经过性能比较,选择催化活性较高且金属溶出量较小的Cu/Ni作催化剂。用催化湿式氧化法处理吡虫啉农药废水,考察了各种因素对处理效果的影响。实验结果表明:在进水pH为6.93、Cu/Ni加入量为4.0g、反应温度为190oC、氧分压为1.6MPa、反应时间为120min的条件下,COD去除率为95%;处理后废水的BOD5/COD从0.093增至0.590,可生化性明显改善。 相似文献
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When a recombinantEscherichia coli XL1-Blue harboring pSYL105 was cultured in a complex medium, a poly(3-hydroxybutyric acid) (PHB) concentration of 7.16 g/L was obtained in 48 h. However, a PHB concentration of only 0.91 g/L was obtained in 60 h by culturing in a defined medium. Also, fed-batch culture in a defined medium resulted in considerably lower PHB accumulation than in a complex medium. With the aim to produce a high concentration of PHB at a reduced medium cost, we examined 10 complex nitrogen sources for their ability to promote PHB synthesis in a defined medium. Tryptone, casamino acids, and casein hydrolysate promoted PHB synthesis to a higher extent than the others tested. PHB synthesis was also enhanced during fedbatch cultures when a defined medium was supplemented with various complex nitrogen sources. With tryptone supplementation a PHB concentration of 66.7 g/L could be obtained in 44 h. Yeast extract was less effective for promoting PHB synthesis than tryptone. Corn steep liquor, which did not enhance PHB synthesis significantly, could promote PHB synthesis considerably when supplemented together with yeast extract in both flask and fed-batch cultures. 相似文献
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采用缺氧—好氧—催化臭氧氧化工艺处理某石化厂的含盐废水。实验结果表明:在进水COD为200~350 mg/L的条件下,经生化处理后的出水COD稳定在50~60 mg/L,COD去除率稳定在75%左右;在臭氧投加量为4.5 g/L、V(催化剂Ⅱ)∶V(废水)=1.5∶1的条件下,进行连续催化臭氧氧化后出水COD稳定在20 mg/L以下,COD去除率大于70%,满足DB 61/224—2011《黄河流域(陕西段)污水综合排放标准》。表征结果显示,催化剂表面含有铜元素,比表面积为250.815 m2/g,吸水率为60.9%,经过滤可去除废水中残留的催化剂。 相似文献
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树脂吸附法处理硝基苯和硝基氯苯生产废水的研究 总被引:34,自引:3,他引:34
研究了用CHA-111树脂吸附处理硝基本和硝基氯苯生产废水的最佳工艺条件,当废水中硝基苯类化合物含量为639mg/L时,CHA-111树脂的工作吸附容量为126mg/mL,处理水量为190BV,处理后硝苯类化合物的浓度〈5mg/L,去除率〉99%;采用异丙醇作脱附剂;表明该树脂的吸附与脱附性能良好。 相似文献
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The purpose of this study was to investigate NOx and SO2-inducednitrogen and sulfur levels accumulated over vegetation and soil in the surrounds of the fertilizer plant in Kütahya, Turkey. Therefore, leaf samples collected from the seven locations adjacent to the plant were morphologically observed (pollution-related injuries and color deformation) and chemically analyzed. Besides, nitrogen and sulfur contents were determined in the soil samples collected from each location. A significant correlation was achieved between locations and different vegetation samples and soil samples. The highest nitrogen level present in the trees was 3.07 ± 0.105% (3rd location, Robinia pseudoacacia), with the highest sulfur level being 5.79 ± 0.085% (3rd location, Salix alba). The highest nitrogen and sulfur levels in soils were 0.31 ± 0.045 and 0.57 ± 0.052% (3rd location), respectively. Furthermore, the highest nitrogen and sulfur levels were 4.69 and 2.20%, respectively,in agricultural plants in the surrounds of the fertilizer plant. A higher level of pollutants was observed in the samples collectedfrom the locations in the direction of the prevailing wind. Also, differences between locations as well as between plant specimens were statistically evaluated. 相似文献
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针对江苏省某化工园区集中式污水处理厂出水COD和TP高于DB32/939—2006《江苏省化学工业主要水污染物排放标准》规定的排放限值的情况,采用Fenton氧化工艺对该污水处理厂装置进行升级改造。小试最佳工艺条件为:初始污水pH 3.0~3.5,H_2O_2(质量分数30%)加入量0.8 m L/L,FeSO_4·H_2O加入量0.8 g/L,反应时间120min,Fenton氧化反应结束后中和反应的适宜pH约为7.0。升级改造工程包括2套并联运行的处理能力各为10 km~3/d的Fenton氧化系统,装置稳定运行后最终控制H_2O_2加入量为150 L/h,FeSO_4·7H_2O溶液加入量为700 L/h,相应的处理后出水COD和TP分别稳定在60 mg/L和0.4 mg/L以下,可达标排放。每吨污水的处理药剂成本约为0.9元。 相似文献
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泥法A/O生物脱氮工艺处理腈纶废水和炼油废水 总被引:2,自引:0,他引:2
采用泥法A/O生物脱氮工艺处理腈纶废水和炼油废水,出水中COD〈100mg/L,NH3-N〈15mg/L。但进水中油〉20mg/L,NH3-N〉700mg/L或SCN^-〉70mg/L时,将对系统产生不良影响。本文介绍了1年来的运行情况,探讨了系统受影响的原因,并提出了改进建议。 相似文献
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Armelle Braud Karine Jézéquel Emilie Vieille Adrien Tritter Thierry Lebeau 《Water, Air, & Soil Pollution: Focus》2006,6(3-4):261-279
Partly because of the low bioavailability of metals, the soil cleaning-up using phytoremediation is usually time-consuming.
In order to enhance the amount of metals at the plant's disposal, the soil bioaugmentation coupled together with phytoextraction
is an emerging technology. In this preliminary work, two agricultural soils which mainly differed in their Cr, Hg and Pb contents
(LC, low-contaminated soil; HC, high-contaminated soil) were bioaugmented in laboratory conditions by either bacterial (Bacillus subtilis, Pseudomonas aeruginosa, Pseudomonas fluorescens or Ralstonia metallidurans) or fungal inocula (Aspergillus niger or Penicillium simplicissimum) and incubated during three weeks. The LC soil pots bioaugmented with A. niger and P. aeruginosa contained higher concentrations of Cr (0.08 and 0.25 mg.kg−1 dw soil) and Pb (0.25 and 0.3 mg.kg−1 dw soil) in the exchangeable fraction F1 (extraction with MgCl2) by comparison with the non-bioaugmented soil where neither Cr nor Pb was detected. Conversely, immobilization of Cr and
Pb in the soil were observed with the other microorganisms. The soil bioaugmentation not only modified the metal speciation
for the most easily extractable fractions but also modified the distribution of metals in the other fractions, to a lesser
extent nevertheless. The difference in microbial concentrations between the bioaugmented or not HC soils reached up to 1.8
log units. Thus the microorganisms that we chose for the soil bioaugmentation were competitive towards the indigenous microflora.
The PCA analysis showed close positive relationships between the microorganisms which potentially produced siderophores in
the soil and the amount of Cr and Pb in the fraction F1. 相似文献
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Xiaoping Hu Satoshi Osaki Miki Hayashi Mureo Kaku Susumu Katuen Hiroshi Kobayashi Fusako Kawai 《Journal of Polymers and the Environment》2008,16(2):103-108
We intended to find thermophilic degraders of terephthalate-containing Biomax® films. Films in mesh bags were buried in composts (inside temperature: approximately 55–60 °C), resulting in the degradation of them in 2 weeks. Fluorescent microscopy of films recovered from composts showed that microorganisms gradually covered the surface of a film during composting. DGGE analysis of microorganisms on the composted film indicated the presence of Bacillus species as main species (approximately 80% of microbial flora) and actinomycetes (approximately 10–20%) as the second major flora. Isolation of Biomax®-utilizing bacteria was focused on these two genera: two actinomycetes and one Bacillus species were isolated as pure best degraders from the composted polymer films, which were fragmented into small pieces. All the strains were thermophilic and identified, based on their 16S rDNA analyses. Degradation of polymer films was confirmed by (1) accelerated fragmentation of films in composts, compared with a control (no inoculum) and resultant decrease in molecular weights, (2) growth in a powdered Biomax® medium, compared with a control without powdered Biomax®, and (3) production of terephthalate in a powdered Biomax® medium. In this way, we concluded that these bacteria were useful for degradation of thermostable Biomax® products. 相似文献
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Hans Preusting Jaap Kingma Gjalt Huisman Alexander Steinbüchel Bernard Witholt 《Journal of Polymers and the Environment》1993,1(1):11-21
WhenPseudomonas oleovorans (GPo1) is grown on sodium octanoate under ammonium limiting conditions, it is able to accumulate a copolyester consisting of medium chain length 3-hydroxyalkanoic acids (PHAm). 3-Hydroxybutyrate is only incorporated in trace amounts. WhenP. oleovorans is equipped with the PHB biosynthetic genes ofAlcaligenes eutrophus (GPo1[pVK101::PP1]), it forms a polyester containing major amounts of 3-hydroxybutyrate. The resulting polymer however is a blend of PHAm and PHB, rather than a copolymer of 3-hydroxybutyrate and medium chain length 3-hydroxyalkanoic acids [11]. To establish whether PHAm and PHB molecules are stored in the same or separate granules by this recombinantP. oleovorans strain, we studied polymer forming cells by freeze-fracture electron microscopy. This approach is possible because previous freeze-fracture electron microscopy studies on PHAm and PHB accumulating strains have shown that PHAm and PHB granules can be distinguished from each other: PHAm granules from mushroom-like structures, whereas PHB granules from needle structures during freeze-fracturing. In this paper we show that stationary phase cells of GPo1[pVK101::PP1] contained both mushroom and needle-like structures, indicating that PHAm and PHB chains were stored in separate granules. To be able to determine whether the separation of PHAm and PHB is complete, the respective granules were separated on sucrose gradients. A total cell extract of GPo1[pVK101::PP1] which was subjected to sucrose gradient centrifugation revealed two white bands of different densities: the upper band with a density of 1.05 g/mL consisted exclusively of PHAm granules, while the lower band with a density of 1.19 g/mL consisted of PHB granules only. Thus, when bacteria synthesize both PHAm and PHB, the resulting polymer chains are segregated completely and stored in separate granules. 相似文献
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A. Chiumenti F. da Borso R. Chiumenti F. Teri P. Segantin 《Waste management (New York, N.Y.)》2013,33(6):1339-1344
Vacuum evaporation consists in the boiling of a liquid substrate at negative pressure, at a temperature lower than typical boiling temperature at atmospheric conditions. Condensed vapor represents the so called condensate, while the remaining substrate represents the concentrate.This technology is derived from other sectors and is mainly dedicated to the recovery of chemicals from industrial by-products, while it has not been widely implemented yet in the field of agricultural digestate treatment. The present paper relates on experimental tests performed in pilot-scale vacuum evaporation plants (0.100 and 0.025 m3), treating filtered digestate (liquid fraction of digestate filtered by a screw-press separator). Digestate was produced by a 1 MWe anaerobic digestion plant fed with swine manure, corn silage and other biomasses. Different system and process configurations were tested (single-stage and two-stage, with and without acidification) with the main objectives of assessing the technical feasibility and of optimizing process parameters for an eventual technology transfer to full scale systems.The inputs and outputs of the process were subject to characterization and mass and nutrients balances were determined.The vacuum evaporation process determined a relevant mass reduction of digestate.The single stage configuration determined the production of a concentrate, still in liquid phase, with a total solid (TS) mean concentration of 15.0%, representing, in terms of mass, 20.2% of the input; the remaining 79.8% was represented by condensate. The introduction of the second stage allowed to obtain a solid concentrate, characterized by a content of TS of 59.0% and representing 5.6% of initial mass.Nitrogen balance was influenced by digestate pH: in order to limit the stripping of ammonia and its transfer to condensate it was necessary to reduce the pH. At pH 5, 97.5% of total nitrogen remained in the concentrate. This product was characterized by very high concentrations of total Kjeldhal nitrogen (TKN), 55,000 mg/kg as average.Condensate, instead, represented 94.4% of input mass, containing 2.5% of TKN. This fraction could be discharged into surface water, after purification to meet the criteria imposed by Italian regulation. Most likely, condensate could be used as dilution water for digestion input, for cleaning floor and surfaces of animal housings or for crop irrigation.The research showed the great effectiveness of the vacuum evaporation process, especially in the two stage configuration with acidification. In fact, the concentration of nutrients in a small volume determines easier transportation and reduction of related management costs. In full scale plants energy consumption is estimated to be 5–8 kWhe/m3 of digestate and 350 kWht/m3 of evaporated water. 相似文献
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Dieter Jendrossek Ingrid Knoke Rahim Bahodjb Habibian Alexander Steinbüchel Hans Günter Schlegel 《Journal of Polymers and the Environment》1993,1(1):53-63
Bacteria capable of growing on poly(3-hydroxybutyrate), PHB, as the sole source of carbon and energy were isolated from various soils, lake water, activated sludge, and air. Although all bacteria utilized a wide variety of monomeric substrates for growth, most of the strains were restricted to degrade PHB and copolymers of 3-hydroxybutyrate and 3-hydroxyvalerate, P(3HB-co-3HV). Five strains were also able to decompose a homopolymer of 3-hydroxyvalerate, PHV. Poly(3-hydroxyoctanoate), PHO, was not degraded by any of the isolates. One strain, which was identified asComamonas sp., was selected, and the extracellular depolymerase of this strain was purified from the medium by ammonium sulfate precipitation and by chromatography on DEAE-Sephacel and Butyl-Sepharose 4B. The purified PHB depolymerase was not a glycoprotein. The relative molecular masses of the native enzyme and of the subunits were 45,000 or 44,000, respectively. The purified enzyme hydrolyzed PHB, P(3HB-co-3HV), and—at a very low rate—also PHV. Polyhydroxyalkanoates, PHA, with six or more carbon atoms per monomer or characteristic substrates for lipases were not hydrolyzed. In contrast to the PHB depolymerases ofPseudomonas lemoignei andAlcaligenes faecalis T1, which are sensitive toward phenylmethylsulfonyl fluoride (PMSF) and which hydrolyze PHB mainly to the dimeric and trimeric esters of 3-hydroxybutyrate, the depolymerase ofComamonas sp. was insensitive toward PMSF and hydrolyzed PHB to monomeric 3-hydroxybutyrate indicating a different mechanism of PHB hydrolysis. Furthermore, the pH optimum of the reaction catalyzed by the depolymerase ofComamonas sp. was in the alkaline range at 9.4. 相似文献