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141.
142.
化学絮凝预处理对膜生物反应器膜污染的影响 总被引:5,自引:0,他引:5
以生活污水为原水,对复合式膜生物反应器(HMBR)与传统膜生物反应器(CMBR)进行了对比研究,探讨化学絮凝预处理对膜污染和除污效果的影响。结果表明,相对于CMBR系统,HMBR系统的膜污染速率很低,在近50d的运行中,HMBR的跨膜压差几乎维持在同一水平,而在同等条件下运行的CMBR则从4.59kPa上升到26.18kPa。EPS分析结果表明,HMBR系统中SMP和LB各组分的浓度相对于CMBR系统大大减小,膜污染的速率得到了大幅降低。化学絮凝预处理可有效减缓后续MBR的膜污染,可以作为膜生物反应器的有效预处理方法。此外,HM-BR的出水水质也优于CMBR系统的。 相似文献
143.
电化学氧化耦合絮凝技术深度处理焦化废水影响因素分析 总被引:1,自引:1,他引:0
采用了电化学氧化耦合絮凝技术处理焦化废水,研究了电流密度、pH值、水力停留时间(HRT)和絮凝剂投加量对CODCr去除效果的影响。研究结果表明,电化学氧化耦合絮凝技术处理焦化废水有较好的协同效应。当进水中CODCr的质量浓度为99 mg/L,在电流密度为30 mA/cm2,HRT为30 min,pH值为6.5,PAM投加量为600 mg/L时,CODCr去除率达到80%以上,出水水质指标稳定,并能达到GB 8978—1996《污水综合排放标准》一级排放标准。 相似文献
144.
The effect that yeast research and development on yeasts has had on the brewing industry is traced from the time of Pasteur to the present time. 相似文献
145.
Flocculation,cell surface hydrophobicity and 3‐OH oxylipins in the SMA strain of Saccharomyces pastorianus 下载免费PDF全文
Three‐hydroxy‐oxylipins (3‐OH oxylipins) have been previously detected in brewing yeast production strains at flocculation onset. In this work, the SMA strain of Saccharomyces pastorianus was characterized during growth in a miniature fermentation assay by measuring flocculation and cell surface hydrophobicity (CSH). Proportions of 3‐OH oxylipin were also measured concurrently during growth in the miniature fermentation assay and a defined 3‐OH oxylipin extraction protocol using ethyl acetate is presented along with a novel derivatization and gas chromatography–mass spectrometry (GC‐MS) detection approach. When the SMA strain was grown in the assay, near maximal CSH and flocculation levels were achieved by a 36 h fermentation time. Under the same culture conditions, the oxylipin 3‐OH decanoic acid (3‐OH 10:0) was identified. This oxylipin could not be detected early in the fermentation, but elevated relative levels of 3‐OH 10:0 were reached by 36 h, coinciding with increased CSH levels. It was previously presumed that the formation of 3‐OH oxylipins at flocculation onset might increase the CSH. However, results from this study suggest that 3‐OH 10:0 may not contribute to cell wall hydrophobicity. The flocculation behaviour of the SMA strain was also monitored in the presence of 3‐OH 10:0, but exposure to this oxylipin did not impact the sedimentation of this yeast, suggesting that 3‐OH oxylipins may not act as mediators of quorum sensing in this strain. Copyright © 2015 The Institute of Brewing & Distilling 相似文献
146.
ABSTRACT: Proteins/polysaccharides complexes could improve emulsifying properties of proteins by thickening the layer at the interface of the oil droplets. Emulsifying properties of whey protein-carboxymethylcellulose complexes (WPI/CMC) were compared with those of a whey protein isolate (WPI). Ingredients were incorporated into oilinwater emulsions with various protein and oil contents. Visual observations, protein load, protein distribution and rheological measurements were used to evaluate emulsion stability. Protein load up to 26.1 and 48.9 mg protein/g oil were obtained for WPI and WPI/CMC emulsions, respectively. The higher protein load of WPI/CMC emulsions and visual observations indicated that WPI/CMC complexes had greater emulsifying properties against coalescence than whey proteins. However, complexes enhanced flocculation of oil droplets. 相似文献
147.
为了提高黄浆水的附加值和利用率,缓解排放黄浆水带来的环境污染,本文对黄浆水中的可溶性固形物进行絮凝处理。在单因素实验基础上结合响应面法对黄浆水中可溶性固形物的絮凝工艺进行优化,并且对絮凝前后黄浆水进行了蛋白质和总糖含量测定、生化需氧量和化学需氧量测定以及代谢组学测定。实验结果表明,絮凝沉降黄浆水可溶性固形物最佳工艺参数为:壳聚糖添加量为0.54 mg/mL,海藻酸钠添加量为0.24 mg/mL,pH为4.4,温度为47 ℃,此时黄浆水可溶性固形物沉降率为(46.26%±0.38%);蛋白质含量下降40.68%、总糖含量下降8.41%;生化需氧量和化学需氧量去除率分别为43%、40.95%。代谢组学实验结果表明:黄浆水絮凝前后有66种化合物含量存在显著变化。本研究结果表明絮凝能有效的降低黄浆水中可溶性固形物的含量,为黄浆水的进一步开发利用提供一定的参考。 相似文献
148.
对某细粒铁矿石开展了磁选-选择性絮凝脱泥试验研究。结果表明, 矿石中磁铁矿为中细粒嵌布, 赤铁矿为微细粒嵌布, 二者嵌连关系紧密; 采用磨矿-强磁选, 可脱除TFe品位7.57%、产率49.40%的尾矿; 将磁选精矿细磨至-0.037 mm粒级含量98.64%, 在矿浆pH值11.6、矿浆浓度34.6%、腐殖酸钠用量0.5 g/L条件下进行四段选择性絮凝脱泥, 可脱除TFe品位12.20%、作业产率31.20%的矿泥。通过磁选-选择性絮凝脱泥大幅提高了反浮选的入选品位、降低了矿石处理量。 相似文献
149.
《分离科学与技术》2012,47(8):1195-1212
ABSTRACT It is shown that hydrophobic flocculation flotation (HFF) is an effective process to treat finely ground ores and slimes so as to concentrate coal and mineral values at a fine size range. The process is based on first dispersing the fine particles suspension, followed by flocculation of fine mineral values or coal in the form of hydrophobic surfaces either induced by specifically adsorbed surfactants or from nature at the conditioning of the slurry with the shear field of sufficient magnitude. The flocculation is intensified by the addition of a small amount of nonpolar oil. Finely ground coals, ilmenite slimes, and gold finely disseminated in a slag have been treated by this process. Results are presented indicating that cleaned coal with low ash and sulfur remaining and high Btu recovery can be obtained, and the refractory ores of ilmenite slimes and fine gold-bearing slag can be reasonably concentrated, leading to better beneficiation results than other separation techniques. In addition, the main operating parameters affecting the HFF process are discussed. 相似文献
150.
《分离科学与技术》2012,47(9):1420-1424
In this study the modified procedure of the oil agglomeration process was carried out, where the emulsion of dodecylammonium hydrochloride (DDAHCl) solution and kerosene was added to the mineral suspension. The aim of this work was to research the oil agglomeration of dolomite mineral by the contact angle, zeta potential and surface free energy measurements. The relationship between the investigated parameters and the oil agglomeration as well as shear flocculation was revealed. The mechanism of oil agglomeration of hydrophilic particles in cationic-anionic surfactant system has been proposed. It was concluded that oil droplets interact rather with aggregates of particles modified by anionic surfactant than the single mineral particles as was explained for naturally hydrophobic particles. 相似文献