硫酸铝在造纸废水处理中的应用

对硫酸铝无机絮凝剂处理造纸厂二沉池出水进行了絮凝效果评价,并与液体聚合氯化铝(PAC)无机高分子絮凝剂进行了对比实验。找到了废水达标排放前提下,硫酸铝、PAC的最佳投加量。     

硫酸铝和聚合氯化铝的比较

传统松香施胶工艺使用硫酸铝作为松香胶的沉淀剂，近年来一些造纸厂在松香施胶中使用聚合氯化铝（PAC）取代硫酸铝。本文对这两种铝化合物进行了比较，实验所用的三种PAC分别由英国三家化学品公司生产。1组成和制备硫酸铝的组成为Al2（SO4）3·nH2O，由氢氧化铝、高岭土或矾土矿石与硫酸反应而制得。施胶用硫酸铝的另一个来源是明矾，它含有硫酸钾和结晶水，可用天然明矾石经煅烧、萃取、结晶而制得。PAC的组成可以用Aln（OH）mCl3n—m来表示，其中n表示聚合度，m表示水解度。PAC可以通过用碱中和氯化铝或用盐酸与氢氧化铝反应而制…     

聚硅硫酸铝絮凝剂处理炼油废水的研究

用自制的聚硅硫酸铝(PSAS)处理炼油废水,效果优于传统使用的聚合氯化铝(PAC),采用两次投加(100mg·L-1+50mg·L-1)减少了絮凝剂用量,处理后达到国家一级排放标准,其中pH范围为7.0～8.0,沉淀时间为30min.若采用一次投加絮凝后砂滤,效果更佳,也简化了处理工艺流程.     

一种新型的复合型絮凝剂处理制革工业废水的研究

以淀粉、铝盐和钙盐为原料 ,分别制备了天然高分子絮凝剂 (SAAF)以及无机高分子絮凝剂聚硅酸氯化铝钙 (PCACS) ,然后在一定的条件下将这两种絮凝剂混合配制成无机有机复合型絮凝剂 F- 1。采用这种新型的复合型絮凝剂 F- 1进行制革工业废水处理试验 ,对其絮凝效果及影响因素进行研究 ,并初步探讨了絮凝动力学。试验结果表明 ,F- 1适用的温度和 p H值范围宽 ,而且絮凝效果好 ,明显优于 PAC、PAM、硫酸铝和 PFS四种常用的絮凝剂。     

聚合氯化铝—有机高分子复合絮凝剂处理造纸废水

用流动电流技术研究了聚合氯化铝（PAC）分别与不同类型有机高分子制备复合絮凝剂（PACP）的电荷特性,并利用透射电镜技术探讨了PACP的结构形貌。同时利用自制的复合絮凝剂对造纸综合废水的浊度,色度和COD的脱除效果进行了研究,结果表明：与PAC相比,PACP的脱除效果有明显地提高;PAC－阳离子型有机高分子复合絮凝剂的效果又优于PAC－阴离子型有机高分子复合絮凝的效果。     

聚合硅酸硫酸铝的絮凝性能

研究了聚合硅酸硫酸铝对高岭土悬浮液的絮凝性能.结果表明,聚合硅酸硫酸铝对高岭土悬浮液具有极好的絮聚作用,其絮凝效果与聚合硅酸硫酸铝的碱化度、加入量和高岭土悬浮液的pH值有关;其絮凝机理主要为吸附架桥与卷扫等作用.     

中性松香造纸施胶体系中沉淀剂的研究进展

为了适应中性松香造纸施胶的发展,聚合氯化铝（PAC）、碱式聚合硅酸硫酸铝（PASS）、聚胺和硫酸铝-阳离子聚合物体系等新沉淀剂被开发和研究,本文综述了这些新型沉淀剂的研究和应用现状。     

聚硅酸硫酸铝絮凝剂铝硅间的相互作用及其絮凝机理

从硅酸的聚合机理及铝盐性质出发,提出了铝盐与聚硅酸颗粒间的作用模型;并利用Zeta电位测定及红外技术对聚硅酸硫酸铝絮凝剂(简称PSAS)的絮凝机理加以分析探讨.结果表明在废水中絮凝剂与废水胶体颗粒间几乎不起化学反应,而主要以物理作用的形式相结合.     

聚合硅酸硫酸铝铁处理造纸中段废水

该文采用硫酸铝、硫酸铁和硅酸钠等为原料,制备聚合硅酸硫酸铝铁（polymeric aluminum ferric sulfate,PAFSS）絮凝剂,研究了n（Si）：n（Al）：n（Fe）、pH等因素对所制PAFSS在去除造纸废水的色度及COD_（Cr）时的影响,对PAFSS的物化特性进行了系统的研究。结果表明：n（Si）：n（Al）：n（Fe）、pH和反应温度对PAFSS性能有重要影响;聚硅酸与铝离子、铁离子及铝铁水解产物间存在一定的络合作用,这种作用对PAFSS聚集体的结构形貌、铝离子和铁离子的水解聚合过程及铝、铁水解产物的形态分布都有一定的影响。在n（Fe＋Al）：n（Si）=3：1、n（Al）：n（Fe）=4：1、pH=4和温度为40℃等条件下制得的PAFSS对废水色度和COD_（Cr）有很好的去除效果,并通过对PAFSS絮凝机理分析,可知PAFSS的絮凝作用主要是通过电中和和吸附架桥2方面实现的。     

木素基絮凝脱色剂的制备与应用

文章在制备木素基絮凝脱色剂时,原料采用了木质素磺酸钙,经过接枝胺甲基化完成制备。并且在最后对脱色剂的脱色效果进行验证,将木素基絮凝脱色剂与硫酸铝复配,并且对两种染料进行脱色。通过实践得出：在条件适宜时,木素基絮凝脱色剂的脱色效果良好。     

3种添加物抑制模拟体系中羟甲基糠醛(HMF)的形成

根据羟甲基糠醛(HMF)形成途径,首先在由其不同反应前体物质构成的模拟反应体系中,研究了碳酸氢钠、碳酸氢铵、食盐、硫酸铝钾和硫酸铝铵对各体系中HMF形成的影响。结果表明:当碳酸氢钠和碳酸氢铵添加量为2.00mg/m L时,美拉德、果糖反应体系中HMF的生成量均显著下降,分别为5.01、3.02 mg/L和3.30、17.52 mg/L;在美拉德、葡萄糖、果糖和蔗糖反应体系中添加0.60 mg/mL硫酸铝钾时,体系中的HMF均明显增高,分别为80.53、13.02、265.02和310.11 mg/L,最大增幅为对照组的620.26倍;而硫酸铝铵处理组HMF的增幅可高达197.00倍。而后考察了5种添加物对饼干中HMF的影响,证实碳酸氢钠、碳酸氢铵和食盐显著降低了饼干中的HMF含量,最大降幅为35.34%。然而,即使在添加了食盐、碳酸氢钠和碳酸氢铵的情况下,硫酸铝钾和硫酸铝铵(0.10 g/80.00 g面粉)仍使饼干中HMF含量增加62.41%和55.64%。综上所述,碳酸氢钠、碳酸氢铵和食盐在模拟体系和饼干中显著减少HMF形成;硫酸铝钾和硫酸铝铵则大幅增加HMF生成量。结果进一步支持了国家限制含铝膨松剂使用的合理性。     

Ecological dyeing of silk fabric with lac dye by using padding techniques

This research focuses on silk fabrics exhibiting different colour values and fastness properties. The samples were prepared by dyeing with lac as a natural colourant. Two padding techniques were used in the process, namely, the pad-batch and pad-dry techniques, under different conditions. Aluminium potassium sulphate, ferrous sulphate, copper sulphate and stannous chloride were used as mordants. The effects of differing dye concentrations added to the silk fabrics using a pre- and post-mordant method were studied and recorded. The colour fastness to washing, light, rubbing, water and perspiration of the dyed samples was performed according to the present ISO standard. Silk fabric dyed without mordant showed a pink shade, while those samples mordanted with stannous chloride and aluminium potassium sulphate displayed noticeably brighter red coloured shades. With the additional use of copper sulphate, the colour shade produced was violet, while darker grey shades were obtained by adding ferrous sulphate mordant. The test results regarding fastness properties ranged from fair to very good, while wash fastness ranged from very poor to poor.     

Ecofriendly natural dyeing of woollen yarn using mordants with enzymatic pretreatments

In this study, woollen yarn was dyed with industrial rose pulp from Isparta, a process that may pose environmental risks. The woollen yarn was processed with Savinase 16L, a protease enzyme, then dyed with biomordants such as citric acid, tannic acid and acetic acid, as well as with metal mordants such as aluminium sulphate, aluminium potassium sulphate, ferrous sulphate and potassium dichromate. The results showed that the yarn pretreated with the protease enzyme exhibited increased dyeability and pilling values without excessive loss of weight or strength. Although different shades were obtained with biomordants, different colours were obtained with metal mordants. The analysis of the waste water and metal content of the final product showed compliance with the OEKO-TEX^® Standard 100.     

絮凝沉降-炉渣过滤深度处理印染废水

经生物曝气氧化后的印染废水,采用聚合氯化铝或聚合硫酸铁作絮凝剂进行絮凝处理。处理工艺为投加量为0.01%,控制pH值为6,絮凝15min,静置4h,再经高温炉渣过滤。色度为200(稀释倍数),CODCr为220mg/L的原废水,经此处理后出水近乎无色,CODCr降低至30mg/L以下,处理出水可用于印染工艺用水。     

Aluminium and fluoride in hospital daily diets and in teas

The levels of aluminium and fluoride have been determined in hospital daily diets including breakfast, dinner and supper, as well as in black teas and herbal teas purchased from the local market. In tea, aluminium was determined directly in a sample solution by atomic absorption spectroscopy using nitrous oxide and an acetylene flame. For analysis of the hospital diet, samples containing lower levels of aluminium were analysed using a spectrophotometric method which measured aluminium in the form of a 8-hydroxyquinoline complex. Decomposition of the samples was achieved using a mixture of concentrated acids [nitric (HNO₃), perchloric (HClO₄) and sulphuric (H₂SO₄)] in platinum dishes. Fluoride was assayed by spectrophotometry using a microdiffusion procedure with a mixture of concentrated HClO₄ and silver sulphate, trace amounts of the released fluoride [as hydrogen fluoride (HF)] were trapped on the alkaline surface of a Petri dish and then determined in the form of an alizarin-fluoride complex. The mean level of aluminium found in hospital daily diets amounted to 21.3±12.3 mg and the mean level of fluoride was 1.38±1.12 mg per adult person. In the 16 samples of commercially available brands of black teas, the levels of aluminium and fluroide ranged from 445 to 1552 ppm (mean=897±264 ppm) and from 30 to 340 ppm (mean 141±85 ppm), respectively. In six herbal teas, the mean levels of aluminium and fluoride were lower, and amounted to 218.9±150.7 ppm and 6.0±6.9 ppm, respectively. This study has shown that concern about a high intake of aluminium and fluoride from these foods is unfounded.     

Sulphate contents and sorption in scottish soils

Phosphate-extractable inorganic sulphate contents of freely drained acid surface soils representing four contrasting soil series in north-east Scotland ranged from 13 to 60 mg S/kg soil. Of this an average of 59% was adsorbed under the conditions of extraction used. The soils were therefore well supplied with available sulphate and there are no known cases of deficiency in the area. Average group contents of adsorbed sulphate were closely related to the abilities of the soils to adsorb added sulpphate, and unlike phosphate retention, sulphate sorption seemed to depend more on active iron than aluminium.     

Gelatinisation Properties of Cassava Starch in the Presence of Salts,Acids and Oxidising Agents

The effect of various cations, anions, acids and oxidising agents on the gelatinisation properties of cassava starch was studied and wide variation was observed in the pasting and swelling properties. Sodium chloride and sodium thiosulphate slightly lowered the peak viscosity of cassava starch with increase in concentration, whereas with sodium sulphite, calcium chloride and sodium hypochlorite, a more significant decrease in the viscosity and breakdown was observed. Ferrous sulphate, alum, aluminium chloride and acids enhanced the peak viscosity at lower concentrations followed by a decrease at 1% and above. Sodium metabisulphite elevated the viscosity at 0.05 and 0.1%, while sodium hypochlorite lowered the viscosity and breakdown. DSC studies showed that aluminium chloride, sodium sulphite, and sodium thiosulphate brought about an increase in T_onset, T_end and ΔH values at higher concentrations. A decrease in swelling volume was observed from 0.05 to 1% concentration of sodium chloride and above that there was a gradual increase. With sodium sulphite, a significant increase in swelling volume was observed at 2.5 and 5% levels. With 0.05 and 0.1% aluminium chloride and sodium metabisulphite an increase in swelling volume was noticed, but at higher concentrations there was a drastic fall. Sodium chloride, sodium sulphite, sodium thiosulphate and calcium chloride brought about decrease in starch paste clarity with increase in salt concentration, whereas ferrous sulphate, aluminium chloride, sodium hypochlorite, hydrochloric acid and acetic acid improved the starch paste clarity.     

THE CAMBRIDGE PRIZE LECTURE 1995: INDIRECT AND DIRECT CONTRIBUTIONS OF BARLEY MALT TO BREWING

The suitability of barley malt as a raw material for brewing is determined by an amalgamation of “indirect” and “direct” contributions to the beer produced. Indirect contributions are considered as those which affect the quality of the brewing process performance whereas direct contributions are considered as those which affect the quality of the product. As a potential indirect contribution of malt to brewing quality evidence is presented that barley malt contains a flocculent which influences mash filterability. As a potential direct contribution of barley malt to beer quality evidence is presented that the mineral silicate found in beer may have a role in moderating dietary aluminium.