3
6月, 2020
从实验室到中试工厂规模的有色废水处理用单宁基混凝剂
摘要：
在实验室和试验工厂的规模内，通过使用甲醛和盐酸二甲胺的曼尼希缩合反应对相思树的树皮单宁提取物进行了改性。在改性过程中改变了一些条件（加热速率、甲醛用量和Mannich溶液活化时间），以评估它们对所得到的产品的剪切粘度和保质期的影响。可以根据反应条件对这些特性进行调整。选择了五种不同剪切粘度（30 cP至430 cP）的改性缩合单宁来测试阴离子（Duasyn直接红和酸性黑2）和阳离子（亚甲基蓝和水晶紫）染料的脱色性能。通过紫外光谱法对其性能进行监测。在不同的pH值（1至14）下，研究了脱色效果。在该工艺中同时加入其他添加剂，即膨润土和阳离子或阴离子聚丙烯酰胺，以最小的剂量加入后一种添加剂，可获得良好的脱色效果（85%至96%的还原率）。一般来说，随着生物混凝剂粘度的增加，脱色性能得到了改善。然而，在实际应用中，粘度较低的改性缩合单宁可能是首选，因为它们的保质期较长，去除效率合理。
关键词：生物 凝聚剂； 凝聚/絮凝剂；脱色剂；单宁 生物 凝聚剂； 凝聚/絮凝；脱色；单宁；结垢剂
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阅读更多Tannin-based Coagulants from Laboratory to Pilot Plant Scales for Coloured Wastewater Treatment
Abstract:
Bark tannin extract from Acacia mearnsii (Mimosa ME单宁酸混凝剂) was modified at laboratory and pilot plant scales via the Mannich condensation reaction using formaldehyde and dimethylamine hydrochloride. Several conditions were varied during the modification procedure (heating rate, formaldehyde dosage, and Mannich solution activation time) to evaluate their influence on the shear viscosity and shelf life of the resulting products. It was possible to tune these properties with the reaction conditions. Modified condensed tannins with five distinct shear viscosities (30 cP to 430 cP) were selected to test the colour removal of anionic (Duasyn Direct Red and Acid Black 2) and cationic (Methylene Blue and Crystal Violet) dyes. The performance was monitored by ultraviolet spectroscopy. Colour removal was studied over different pH levels (1 to 14). Good decolouration results (85% to 96% reduction) were obtained with the simultaneous introduction of other additives to the process, which were bentonite and a cationic or anionic polyacrylamide, with minimal dosages of the latter additives. An improvement to decolouration performance with an increase in the biocoagulant viscosity was typically observed. However, for practical applications, modified condensed tannins with a lower viscosity may be preferred because they exhibited a longer shelf life and presented reasonable removal efficiencies.
Keywords: Biocoagulant; Coagulation/flocculation; Decolouration; Tannin; Scale-up
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单宁基混凝剂在污水处理中的放大应用：在水处理厂的表现
摘要
涂料生产废水（PMW）中含有剧毒和有机的生物还原性化合物，对人体健康有不利影响。为了评估天然和合成混凝剂对PMW的处理效率，进行了罐装实验。为此，使用了单宁基聚合物（TBP）（单宁混凝剂 单宁凝结剂 单宁絮凝剂 单宁助凝剂）、氯化铁（FeCl3）和硫酸铝（Al2（SO4）3）。结果表明，TBP比凝固剂盐类更有效。涉及TBP的混凝-絮凝剂对原废水或处理后的废水都不需要调整pH值。与金属盐相比，TBP可实现87%以上的COD和99%以上的色度去除率，并且产生的脱泥量也比金属盐少。混凝剂的效率排名如下。TBP > FeCl3 > Al2(SO4)3。TBP作为一种天然的混凝剂，在涂料生产废水处理上可作为合成产品的替代品。
21
5月, 2020
Up-scaling of tannin-based coagulants for wastewater treatment: performance in a water treatment plant
Abstract
Tannin extracts from the bark of Acacia mearnsii and wood of Schinopsis balansae, commonly known as Quebracho, were employed. These were modified at laboratory sale via the Mannich aminomethylation with formaldehyde and dimethylamine hydrochloride. Some reaction conditions were varied, namely the formaldehyde dosage and reaction time, while keeping the Mannich solution activation time constant, and their influence on the shear viscosity of the created bio-coagulants was evaluated. The effect of the final pH of the products on their shear viscosity was also analyzed. Up-scaling of the Mannich reaction for tannin from South Africa was performed and the procedure developed at 1-L scale was reproducible in upscaled conditions. One example of a modified South Africa tannin and the modified Quebracho tannin was subsequently selected for the treatment of an industrial wastewater and tested for color and turbidity reduction in jar tests. The effluent treatment was carried out in a single and dual system with cationic synthetic flocculation agents of different charge degree. Good turbidity and decoloration results (93 and 89% reduction, respectively) were obtained with the simultaneous introduction of a cationic, 40% charged polyacrylamide, with minimal dosage (5 ppm) of the latter additive. The tannin-based coagulant from Acacia mearnsii was successfully applied in dual system with cationic polyacrylamide flocculant for industrial wastewater treatment at pilot plant scale. It was shown to satisfactorily treat the water and generate less sludge.
单宁基天然混凝剂在水处理中的应用：无机化学药剂的替代品
摘要
在这项研究中，建议用一种天然的本土凝固剂来替代明矾。单宁酸存在于树木的叶子、果实、树皮、树根和木材中。研究了从金合欢中获得的单宁的凝固特性,确定了单宁是否可以作为主要凝固剂。以金合欢树树皮中的粉末状物质提取物为研究对象,对其凝固率和剂量进行了测试。采用便携式仪器对地表水样品的浊度和其他物理化学成分进行了测定。浊度计用于测定浊度，数字式pH计用于测定pH值。总悬浮物采用比重法进行分析。实验采用混凝剂用量分别为1.0、2.0、3.0、3.0、4.0和5.0 mL，每份原水样品的间隔为1 mL。结果表明，在3.0 mL/L的最佳投加量下，刺槐粉的去除浊度可达91%。另一方面，刺槐儿茶粉可去除总溶解性固体的57.3%，而其他参数的去除率不高
关键词: 凝固剂，单宁酸，相思茶，浊度，总溶解度，总溶解度
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Use of Tannin based natural coagulants for water treatment:An alternative to inorganic chemicals
Abstract:
In this study, a natural indigenous coagulant is suggested as a substitute for alum. Tannins are foundin the leaves, fruits, barks, roots and wood of trees. The coagulant characteristics of the tannins obtained fromAcacia catechu were examined and whether or not tannins could be used as a primary coagulant wasdetermined. The powdered material extract obtained from bark of acacia catechu was used to test coagulant rateand dose. The turbidity and other physico-chemicals of surface water sample were measured before and afterthe jar-test by using portable instruments. Turbidity meter was used to measure turbidity, while digital pH meterwas used to measure pH. Total suspended solids were analyzed using gravimetric method. The experimentswere carried out with coagulant dosage of 1.0, 2.0, 3.0, 4.0 and 5.0 mL with the intervals of 1 mL in each rawwater sample. The results have shown that acacia catechu powder can remove turbidity up to 91% at the optimaldosage of 3.0 mL/L. On the other hand, the powder of acacia catechu can remove total dissolve solids by 57.3%but not other parameters.
Keywords: Coagulant, Tannins, Acacia catechu, Turbidity, Total dissolve solids
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一种单宁类混凝剂与金属盐类混凝剂在涂料生产废水处理中的凝固效果比较
摘要
涂料生产废水（PMW）中含有剧毒和有机的生物还原性化合物，对人体健康有不利影响。为了评估天然和合成混凝剂对PMW的处理效率，进行了罐装实验。为此，使用了单宁基聚合物（TBP）、氯化铁（FeCl3）和硫酸铝（Al2（SO4）3）。结果表明，TBP比凝固剂盐类更有效。涉及TBP的混凝-絮凝剂对原废水或处理后的废水都不需要调整pH值。与金属盐相比，TBP可实现87%以上的COD和99%以上的色度去除率，并且产生的脱泥量也比金属盐少。混凝剂的效率排名如下。TBP > FeCl3 > Al2(SO4)3。TBP作为一种天然的混凝剂，在涂料生产废水处理上可作为合成产品的替代品。
关键词： 混凝-絮凝；单宁基聚合物 混凝-絮凝；涂料生产废水；单宁基高分子聚合物
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Coagulation efficacy of a tannin coagulant agent compared to metal salts for paint manufacturing wastewater treatment
Abstract
Paint manufacturing wastewaters (PMW) contain highly toxic and organic biorefractory compounds and have adverse effects on human health. Jar-test experiments are conducted in order to assess the efficiency of natural and synthetic coagulants on the treatment of PMW. For this purpose a tannin-based polymer (TBP), iron chloride (FeCl3), and aluminum sulfate (Al2(SO4)3) have been used. The results indicate that TBP is more effective than coagulant salts. Coagulation–flocculation involving TBP does not require any pH adjustment either on raw or on treated wastewater. TBP achieves more than 87% of COD and 99% of color removal and produces less volume of decanted sludge than metal salts. The ranking of the efficiency of coagulant agents is as follows: TBP > FeCl3 > Al2(SO4)3. TBP as a natural coagulant can be a potential substitute for synthetic products on paint manufacturing wastewater treatment.
Keywords: Coagulation–flocculation, Paint manufacturing wastewater, Tannin-based polymer
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用单宁混凝剂处理地表水，用栲栳栳草的单宁类混凝剂处理地表水
摘要
对名为Silvafloc的单宁类混凝剂进行了地表河水澄清试验。这种新型的混凝剂可用于饮用水处理，它是由一种化学改性的栲胶（Schinopsis balansae，俗称Quebracho colorado）组成。小剂量的混凝剂达到了较高的浊度去除率，在中性pH值和室温下的操作条件下，用20mg L-1的混凝剂可达到90%的浊度去除率。在Jar试验中的快速和缓慢混合时间以及搅拌强度进行了评估，发现它们比混凝剂剂量的流入量少。Silvafloc能达到明显的消毒效果（粪链球菌和粪大肠菌群约99.9%，总大肠菌群高达70%）。处理后的水也呈现出很低的多酚含量（约0.4 mg L-1），有机物含量没有增加，但去除率约为30%。如果与其他天然或无机混凝剂相比，Silvafloc比硫酸铝（一种传统的金属盐）在水体澄清方面的效率更高。
Keywords
单宁酸 地表水 浊度去除 混凝-絮凝剂 天然混凝剂