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1.
一种新型絮凝剂的合成及应用   总被引:1,自引:0,他引:1  
本文论述了聚丙烯酰胺类絮凝剂的国内外的生产状况,针对氧化铝生产工艺中赤泥快速分离确定了絮凝剂的几个主要参数,并在实验室和实际生产中进行了不同絮凝剂絮凝沉降的对比试验,证明该絮凝剂在氧化铝生产工艺中应用性能优良。  相似文献   

2.
概述无机絮凝剂、有机高分子絮凝剂和微生物絮凝剂的组成和反应机理,并分别介绍3种絮凝剂在钢铁废水处理方面的应用。最后指出絮凝剂在钢铁废水处理方面的发展趋势。  相似文献   

3.
改性聚丙烯酰胺在赤泥沉降中的应用   总被引:3,自引:1,他引:2  
钱介文  钟宏  卢红梅 《稀有金属》2001,25(4):294-296
用聚丙烯酰胺通过正交试验法改性合成了含有氧肟酸基团的水溶性高分子;将改性产品和工厂提供的絮凝剂用于赤泥沉降,发现改性产品具有上清液浓度小、絮团结实、底流固液比高的优势。  相似文献   

4.
微生物絮凝剂(Microbial flocculants,MBF)因其具有高效、无毒、无二次污染、用途广泛等特点而备受人们关注,被称为第3代絮凝剂.针对微生物絮凝剂在制备过程中由于菌体培养基成本过高而难以推广工业化生产的问题,介绍了国内外关于利用廉价有机物或有机废水作为替代碳源、氮源及直接作为替代培养基制备微生物絮凝剂的研究情况,并分析了微生物絮凝剂研制的发展前景.  相似文献   

5.
采用45120-阴离子聚丙烯酰胺(PAM)为絮凝剂,通过絮凝剂作用沉淀溶液中悬浮的细小颗粒、胶体、硫化物等杂质,考察了不同絮凝剂用量对电解金属锰产量及电耗的影响。结果表明:絮凝剂按每池18 g添加后,在24 h的1个电解周期,车间电解金属锰产量比平时高500 kg,单板由3.06 kg提高至3.15 kg,电解金属锰直流电耗下降130 k W·h/t。  相似文献   

6.
[目的]研究阳离子型聚丙烯酰胺絮凝马铃薯深加工工艺蛋白废液的最佳条件.[方法]以3%聚丙烯酰胺为絮凝剂,研究不同温度、pH、絮凝剂用量、处理时间等对马铃薯深加工的废液絮凝效果的影响.[结果]每100 ml马铃薯深加工工艺蛋白废液,在3%聚丙烯酰胺用量为8 ml、pH为5.5、处理时间为36 h、温度为30℃条件下进行絮凝,有机污染物(COD<,Cr>)的沉降率可达53.69%.[结论]有机絮凝剂阳离子型聚丙烯酰胺能有效絮凝沉淀马铃薯深加工工艺蛋白废液中的大量有机污染物,达到用微生物净化去污需要的目标要求.  相似文献   

7.
王贤纲 《湿法冶金》2011,(3):245-247
研究了以粉煤灰为主要原料制备聚硅酸铝铁无机高分子絮凝剂,考察了絮凝剂用量、水样pH、温度对洗煤废水处理效果的影响及作用机制。结果表明:该絮凝剂对洗煤废水具有较好的处理效果,其对废水的处理是电荷中和、吸附架桥和网捕卷扫等共同作用的结果。  相似文献   

8.
本文论述了微生物絮凝剂的研究进展以及生物絮凝剂的絮凝机理,对氧化铝生产当前应用絮凝剂现状作了简要概述。比较微生物絮凝剂和有机、无机高分子絮凝剂的优越性,分析了微生物絮凝剂在氧化铝生产中的应用前景。  相似文献   

9.
以硝酸铈铵为引发剂,利用二甲基二烯丙基氯化铵(DMDAAC)在羧甲基壳聚糖骨架上的接枝反应,制备了羧甲基二甲基二烯丙基氯化铵壳聚糖(CMCTS-DMDAAC).通过三因素三水平正交实验得出羧甲基壳聚糖与DMDAAC反应的优化实验条件为:反应温度为90℃,反应pH为7.0,反应时间为2 h,引发剂用量为占羧甲基壳聚糖质量的1.5%,单体用量为羧甲基壳聚糖质量的1.5倍.反应产物的结构通过红外光谱、紫外光谱、热重/差热分析、X-衍射及扫描电镜进行了表征.  相似文献   

10.
有机高分子絮凝剂与蛋白质的相互作用   总被引:2,自引:1,他引:1  
赵博欣  余江 《化工冶金》1999,20(2):162-166
以溶菌酶为模型蛋白质,系统研究了溶液化学环境(pH值、盐效应、絮凝剂用量对部分水解的聚丙烯酰胺(PHP)絮凝过程的影响。结果表明:溶液化学环境对絮凝效果及絮体的成长有很大的影响。对体系的ζ电位进行了测定,进一步揭示出在PHP对溶菌酶体系中,絮凝机理以电中和机理为主,同时架桥机理也起一定作用。  相似文献   

11.
以亚熔盐法处理拜耳赤泥所得料浆为研究对象,以沉降速度、澄清度、分层效果为评价指标,采用量筒试验法考察了Nalco-9779、BASF-HP20、Lcb8、L1bb和90HS等有机高分子絮凝剂的絮凝性能,最终筛选出最佳絮凝剂为Nalco-9779。重点考察了时间、温度、添加量和碱浓度等因素对Nalco-9779絮凝性能的影响,结果表明,Nalco-9779絮凝沉降的最佳工艺条件为:沉降时间10min、温度100℃、Na2O浓度小于540g/L、添加量每吨赤泥160g。  相似文献   

12.
经过一系列的选矿工艺处理后形成的氰化尾矿粒度较细,难以沉降,导致回水中固含量较高,直接回用会影响浮选指标,从而限制了回水利用率的提高。针对如何加速氰化尾矿沉降的问题,着重研究2个方面:(1)通过加入常用无机与有机絮凝剂GG、HPAM、PAC和PFS对氰化尾矿浆进行絮凝沉降实验,确定其最佳用量及适宜的除浊pH值范围;(2)将无机与有机絮凝剂复合探究其对氰化尾矿浆的絮凝沉降效果,从而确定二者的最佳复合用量。  相似文献   

13.
喻东  王雷  杨萍  张予伟 《中国冶金》2016,26(5):68-72
在过去的几十年中,传统的聚丙烯酸酯絮凝剂被广泛用于拜耳法赤泥沉降过程中。不断改进的工艺流程使聚合物絮凝剂的发展速度提高20%,甚至更多。利用链增长聚合技术,合成了新型刚性杆结构丙烯酸酯聚合物,通过对比试验发现,新型刚性杆结构絮凝剂的投用可以优化沉降指标,降低氧化铝生产用絮凝剂的消耗量。提出了具体试验及结论,并对新型絮凝剂的其他优异性能有所涉及。  相似文献   

14.
纳米SiO2复合材料研究进展   总被引:1,自引:0,他引:1  
利用纳米SiO2粒子本身所具备的优良性质,通过物理或化学方法使其与不同材料如金属、半导体、无机或有机材料复合,可以制得各种具有特殊性能的纳米复合材料.该文概述了纳米SiO2的优异性能;综述了纳米SiO2/金属、纳米SiO2/无机和纳米SiO2/有机复合材料的研究现状及进展,其中对纳米.SiO2/有机复合材料的综述最详,计有纳米SiO2/酯类、纳米SiO2胺类、纳米SiO2/木材、纳米SiO2/环氧树脂、纳米SiO2/聚烯烃类和纳米SiO2/橡胶等6类复合材料.此外,还指出了有待进一步探索与开发的问题,并对其发展做了展望.  相似文献   

15.
储金宇  汪松美  吴春笃 《黄金》2006,27(5):48-50
研究了一种化学耗氧量、浊度很高的废水絮凝过程。首先,对不同的絮凝剂进行筛选。以COD、浊度为指标,选出最佳絮凝剂;然后,对选定的絮凝剂,在不同的因素下进行试验,找出最佳试验条件,各种因素分别为:絮凝剂的加入量、pH、搅拌速度、沉降时间。以不同的絮凝剂采处理废水,试验结果表明,Al2(SO4),絮凝效果最好。采用单因素对Al2(SO4),絮凝废水进行优化试验,结果表明,絮凝剂加入量与料液比值为0.85g/L、pH为7、搅拌速度为130r/min、沉降时间为80min.絮凝效果最好。  相似文献   

16.
Fe2(SO4)3-壳聚糖絮凝剂的制备及絮凝性能的研究   总被引:1,自引:0,他引:1  
本文以无机絮凝剂Fe2(SO4)3与壳聚糖复配进行絮凝性能研究,并对实际食品废水进行处理。实验表明,以高岭土悬浮液为絮凝对象,当pH值为7,温度为30℃,搅拌时间为5min时,Fe1(SO4)3-壳聚糖絮凝剂的絮凝效果为最佳而且优于单独使用无机絮凝剂Fe2(SO4)3和天然高分子絮凝剂壳聚糖。以实际食品废水为絮凝对象,Fe2(SO4)3-壳聚糖的絮凝效果优于Fe2(SO4)3-壳聚丙烯酰胺复配絮凝剂的絮凝效果。  相似文献   

17.
The first list of plastics additives which may be assigned restrictions in a future amendment to Directive 90/128/ EEC is likely to contain over 200 substances. If food consumption factors are taken into account many compounds on this list could have restrictions removed but there would, without doubt, still be many additives with restrictions. Extensive migration testing of food contact plastics containing restricted additives to ensure compliance would be required. These limits would be difficult to enforce, add significant cost burdens on the packaging industry and, for these reasons, may not provide improved consumer safeguards. An alternative means of control has been proposed based upon polymer composition. However, in order to support such a scheme a reliable correlation between migration of additives to their composition in the polymer must be demonstrated. There has been strong interest in establishing this relationship and a feasibility project to investigate the specific migration of four commonly used additives has been successfully completed. The study was initially funded for 1 year, by the Ministry of Agriculture, Fisheries and Food (MAFF) and industry. Analytical methods to determine the additives in food simulants have been developed and linear correlations have been demonstrated between the concentration of all four additives and their specific migration levels for each polymer studied. Experimental migration data have been compared with those generated by mathematical models.  相似文献   

18.
The performance of two flocculants on turbidity reduction was studied. The two flocculants were: a biopolymeric flocculant which was extracted from fruit waste and a commercial industrial flocculant. The effect of the flocculants’ average molecular weight on turbidity treatment, the treatment efficiency of both flocculants and the flocculants’ degradability were investigated. Response surface methodology was carried out using Box Behnken design to find the optimal pH, cation concentration, and flocculant dosage to maximize the turbidity reduction. The results showed that the maximum turbidity reduction by industrial flocculant occurs between pH 7.5 and pH 8.2, cation concentration between 0.02 and 0.06 mM, and industrial flocculant dosage between 6.5 and 8.0 mg/L. While with biopolymeric flocculant, maximum turbidity reduction occurred between pH 4.6 and pH 7.5, cation concentration between 0.60 and 0.95 mM, and biopolymeric flocculant dosage between 4 and 6 mg/L.  相似文献   

19.
An amino acid as a cofactor for a catalytic polynucleotide   总被引:3,自引:0,他引:3  
Natural ribozymes require metal ion cofactors that aid both in structural folding and in chemical catalysis. In contrast, many protein enzymes produce dramatic rate enhancements using only the chemical groups that are supplied by their constituent amino acids. This fact is widely viewed as the most important feature that makes protein a superior polymer for the construction of biological catalysts. Herein we report the in vitro selection of a catalytic DNA that uses histidine as an active component for an RNA cleavage reaction. An optimized deoxyribozyme from this selection requires L-histidine or a closely related analog to catalyze RNA phosphoester cleavage, producing a rate enhancement of approximately 1-million-fold over the rate of substrate cleavage in the absence of enzyme. Kinetic analysis indicates that a DNA-histidine complex may perform a reaction that is analogous to the first step of the proposed catalytic mechanism of RNase A, in which the imidazole group of histidine serves as a general base catalyst. Similarly, ribozymes of the "RNA world" may have used amino acids and other small organic cofactors to expand their otherwise limited catalytic potential.  相似文献   

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