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排序方式: 共有658条查询结果,搜索用时 15 毫秒
641.
膜生物反应器在废水处理中的应用及研究 总被引:1,自引:0,他引:1
膜生物反应器是将生物反应器与膜分离技术相结合的一种高效废水处理新技术。介绍了膜生物反应器的类型、特点以及其在处理生活污水、工业废水、垃圾渗透液、粪便污水和中水回用中的研究和应用现状,提出了膜生物反应器所存在的问题及其研究进展。 相似文献
642.
钻井污水处理的实验研究 总被引:1,自引:0,他引:1
钻井污水是油田开发中的主要环境污染物之一。其成分复杂,使得CODCr值高而处理难度大。以渤深6井为研究对象,采用混凝与微电解相结合处理废水。试验结果表明,原水的CODCr从35 155 mg/L降到186 mg/L,达到二级排放标准。 相似文献
643.
644.
强力霉素废水的吸附-混凝预处理研究 总被引:1,自引:0,他引:1
根据强力霉素废水的特点,采用吸附-混凝联合处理工艺对其进行预处理研究。筛选出最佳吸附剂、混凝剂、助凝剂,考察了其投加量、pH、反应时间、搅拌强度等因素对处理效果的影响。实验表明,选用粉煤灰作为吸附剂、聚合氯化铝(PAC)作为混凝剂、羟乙基田菁胶(ESG)作为助凝剂,F-去除率达到99.9%,氟浓度降至10mg/L以下;化学需氧量(CODCr)去除率达到37.5%,生化需氧量/化学需氧量(BOD5/CODCr)由原来的小于0.1提高至0.16,提高了原废水的可生化性。而且处理后的灰渣烧制成砖块,不会对环境造成二次污染,达到了以废治废的目的。 相似文献
645.
羧甲基壳聚糖对染料废水的脱色研究 总被引:6,自引:0,他引:6
纺织工业是我国重要的经济部门,也是我国工业废水的排放大户,其中印染废水排放量又占纺织工业废水排放量的80%,已成为我国各大水域的重要污染源。印染废水的两大污染指标是色度和COD,污染的特点和处理的难点是色度高,脱色困难[1-2]。作为一种天然生物高分子,壳聚糖(chitosan,简称CTS)以其独有的絮凝、成膜、吸附、螯合等性能在印染废水脱色研究领域得到广泛应用[3-8]。作为絮凝剂处理废水时,壳聚糖由于水溶性差而需先溶于稀酸,应用受到一定限制,故人们纷纷将其改性制成水溶性的羧甲基壳聚糖(carboxy-methyt chitosan,简称NOCC)。张秋华[… 相似文献
646.
Afaq Ullah KHAN Faheem SHAH Rafaqat Ali KHAN Bushra ISMAIL Asad Mohammad KHAN Haji MUHAMMAD 《Turkish Journal of Chemistry》2021,45(4):1201
Every year, tuberculosis affects the lungs of millions of people and rifampicin is the commonly used medicine for its treatment due to its antibiotic nature. The frequent use of rifampicin may lead to its increased concentration in the water resources. This research work is focused on the cloud point extraction (CPE) procedure for the preconcentration of rifampicin prior to its determination in water. The UV/vis spectrophotometric method was adapted for the measurement of rifampicin content after the phase separation. Triton-X 100 was used as the nonionic surfactant which contains hydrophilic polyethylene chain feasible for the extraction of analyte. Various analytical parameters that can affect the extraction efficacy were optimized to achieve linearity of the proposed method in the concentration range of 3.54–81.41 mgL–1. The Limit of detection and quantification were 1.261 and 4.212 mgL–1, respectively. The Preconcentration factor was 40 with relative standard deviation (%RSD) of 2.504%. The standard addition methodology was adopted for the validation of this procedure and effectively applied for the determination of rifampicin in real wastewater samples. 相似文献
647.
648.
Mahdi Shahriarinour Faten Divsar Fereshteh Kamalpour Dahka Sharareh Nezamivand Chegini Mohamad Mahani Arash Moeini Pierfrancesco Cerruti 《Molecules (Basel, Switzerland)》2022,27(1)
The release of pharmaceutical wastewaters in the environment is of great concern due to the presence of persistent organic pollutants with toxic effects on environment and human health. Treatment of these wastewaters with microorganisms has gained increasing attention, as they can efficiently biodegrade and remove contaminants from the aqueous environments. In this respect, bacterial immobilization with inorganic nanoparticles provides a number of advantages, in terms of ease of processing, increased concentration of the pollutant in proximity of the cell surface, and long-term reusability. In the present study, MCM-41 mesoporous silica nanoparticles (MSN) were immobilized on a selected bacterial strain to remove alprazolam, a persistent pharmaceutical compound, from contaminated water. First, biodegrading microorganisms were collected from pharmaceutical wastewater, and Pseudomonas stutzeri was isolated as a bacterial strain showing high ability to tolerate and consume alprazolam as the only source for carbon and energy. Then, the ability of MSN-adhered Pseudomonas stutzeri bacteria was assessed to biodegrade alprazolam using quantitative HPLC analysis. The results indicated that after 20 days in optimum conditions, MSN-adhered bacterial cells achieved 96% biodegradation efficiency in comparison to the 87% biodegradation ability of Pseudomonas stutzeri freely suspended cells. Kinetic study showed that the degradation process obeys a first order reaction. In addition, the kinetic constants for the MSN-adhered bacteria were higher than those of the bacteria alone. 相似文献
649.
This study investigated acid splitting wastewater (ASW) and interphase (IF) from soapstock splitting, as well as matter organic non glycerol (MONG) from glycerol processing, as potential substrates for biogas production. Batch and semicontinuous thermophilic anaerobic digestion experiments were conducted, and the substrates were preliminary treated using commercial enzymes kindly delivered by Novozymes A/C. The greatest enhancement in the batch digestion efficiency was achieved when three preparations; EversaTransform, NovoShape, and Lecitase were applied in the hydrolysis stage, which resulted in the maximum methane yields of 937 NL/kg VS and 915 NL/kg VS obtained from IF and MONG, respectively. The co-digestion of 68% ASW, 16% IF, and 16% MONG (wet weight basis) performed at an organic loading rate (OLR) of 1.5 kg VS/m3/day provided an average methane yield of 515 NLCH4/kg VSadded and a volatile solid reduction of nearly 95%. A relatively high concentration of sulfates in the feed did not significantly affect the digestion performance but resulted in an increased hydrogen sulfide concentration in the biogas with the peak of 4000 ppm. 相似文献
650.
Lead pollution is a severe health concern for humankind. Utilizing water contaminated with lead can cause musculoskeletal, renal, neurological, and fertility impairments. Therefore, to remove lead ions, proficient, and cost-effective methods are imperative. In this study, the Odaracha soil which is traditionally used by the local community of the Saketa District was used as a novel low-cost technology to adsorb lead ions. Odaracha adsorbent was characterized by scanning electron microscopy and Fourier transform infrared spectroscopy. The adsorption process followed the batch adsorption experiment. The response surface method was implemented to derive the operating variables’ binary interaction effect and optimize the process. According to the study’s experimental result, at optimum experimental conditions Odaracha adsorbent removes 98.17% of lead ions. Based on the result of the central composite design model, the Pb2+ ion removal efficiency of Odaracha was 97.193%, indicating an insignificant dissimilarity of the actual and predicted results. The coefficient of determination (R2) for Pb2+ was 0.9454. According to the factors’ influence indicated in the results of the central composite design model, all individual factors and the interaction effect between contact time and pH has a significant positive effect on lead adsorption. However, other interaction effects (contact time with dose and pH with dose) did not significantly influence the removal efficiency of lead ions. The adsorption kinetics were perfectly fitted with a pseudo-second-order model, and the adsorption isotherm was well fitted with the Freundlich isotherm model. In general, this study suggested that Odaracha adsorbent can be considered a potential adsorbent to remove Pb2+ ions and it is conceivable to raise its effectiveness by extracting its constituents at the industrial level. 相似文献