从小麦淀粉废水中分离回收戊聚糖的方法研究

发布时间：2018-02-12 10:49

  本文关键词： 小麦废水 膜分离 戊聚糖 纤维素柱柱层析 分离方法　出处：《华南理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：小麦加工的废水中含有大量可回收、利用价值高的戊聚糖、蛋白质等有机物,但当前小麦淀粉加工厂很少会对其重视,大部分都是排放到污水处理站处理,有的甚至直接排放。这不仅造成资源的浪费,还会对环境造成严重污染。传统的废水处理方法如蒸发浓缩、生物处理、化学处理等耗能大、流程长、处理成本高,对企业造成较为沉重的经济负担。小麦废水的低成本处理和资源的高价值回收利用是全行业的共性难题。本文提出利用直接膜分离法、层析交换分离法、沉淀蛋白/膜分离组合法、酶解蛋白/膜分离组合法等四种途径从小麦淀粉废水中分离回收高价值的戊聚糖,分别展开试验研究。根据实验结果对四种方法做出横向比选,为小麦淀粉废水中戊聚糖的回收利用工程化提供参考依据。此外,本文还对戊聚糖的单糖组成进行了光谱辨识,检测了聚合物的分支程度。直接膜分离法实验研究表明,当透过液为100m L,截留液700m L时,10000Dalton(以下简称Da)超滤膜对戊聚糖的截留率达到97.81%,对蛋白质的截留率达到97.75%,这两种物质的截留液和透过液的浓度比值分别为15.29和10.48,表明10000Da的超滤膜对这两种物质有很好的截留能力。而还原糖和氨基酸的截留液和透过液浓度比值都接近1,表明10000Da超滤膜对还原糖和氨基酸没有截留能力。实验用20000Da和50000Da膜片进行超滤实验,数据显示蛋白质和戊聚糖的截留液和透过液浓度比值都接近1,表明这两种膜片对蛋白质和戊聚糖都没有截留功能。本实验分别用蛋白酶酶解、热凝聚法、生物絮凝剂、等电点沉淀法、三氯乙酸絮凝法,五种方法预先去除小麦淀粉加工废水中的蛋白质,为膜分离回收戊聚糖提供前提条件。实验结果显示,蛋白质的去除效果有很大差异。蛋白质去除率分别是蛋白酶法(87.11%)三氯乙酸法(68.50%)天然高分子絮凝法(20.29%)热凝聚法(17.51%)等电点法(8.56%)。同时,五种处理方法戊聚糖的损失率分别为:三氯乙酸法(22.89%)蛋白酶法(12.93%)有机高分子絮凝法(11.21%)热凝聚法(9.16%)等电点法(8.24%)。以蛋白质去除率和戊聚糖保留率为考核指标,最终确定蛋白酶解方法为适宜的去蛋白方法。废水经蛋白酶预处理后蛋白去除率为87.11%,戊聚糖只损失12.93%。后续再采用直接膜分离法,使用10000Da的膜,戊聚糖基本上能够被截留回收。在上述实验的基础上,本实验设计了酶解和膜分离组合的方法:先将蛋白质分解为氨基酸,然后再用10000Da超滤膜将氨基酸、还原糖和戊聚糖分开。酶解/超滤实验结果表明,当透过液达到待分离液体积的1.5倍时(循环过程补水),全过程蛋白质总的去除率为92.27%,对还原糖和氨基酸(蛋白质酶解产物)的保留率仅24.16%和28.10%,戊聚糖总的保留率为77.36%。10000Da的超滤膜对还原糖和蛋白质降解后的产物氨基酸无截留功能。因此,增加循环次数、延长超滤时间能达到去除废水中蛋白质水解产物(氨基酸)和还原糖、截留戊聚糖的效果。本文尝试了层析交换分离法回收戊聚糖。采用DEAE-52纤维素作为层析介质,以水为洗脱剂,加入适量Na Cl增强洗脱效果。分段收集洗脱液,用冻融分析法定性判断分离效果,采用紫外分光光度法分析蛋白质含量,选择离子色谱定量分析戊聚糖(包含还原糖)。同时,用红外光谱辅助分析判断洗脱液中固体成分的化学物质结构。实验结果表明,整个戊聚糖洗脱分布曲线完全符合典型的层析分离规律,分离操作条件选择是成功的,DEAE-52纤维素树脂适合分离戊聚糖,分离效果良好。冻融法和紫外分光光度法检测结果证明了层析洗脱液中绝大部分是可溶性戊聚糖,基本不含蛋白质和氨基酸等杂质。红外光谱图中917.12 cm—1处显现β—D—半乳吡喃糖的特征峰,841.12 cm—1处出现α—D—葡萄吡喃糖的特征峰,表明该多糖有α-糖苷键和β-糖苷键。将回收得到的戊聚糖采用酸水解法转化为单糖,用糖离子色谱仪检测单糖种类归属。检测结果表明小麦淀粉废水中分离出来的戊聚糖主要由阿拉伯糖、木糖、半乳糖和葡萄糖四种单糖组成。N(Ara)/n(Xyl)比值为0.92,反映出戊聚糖聚合物的分支程度比较大。总体评价,在上述四种分离方法比选中,以蛋白酶解/膜分离组合法为佳。操作流程相对简单,分离率比较高,在分离回收戊聚糖的同时还可以进一步得到氨基酸和还原糖。如果最终能够实现工业化,经济效益应该比较高,所以应用前景预期比较好。
[Abstract]:Wheat processing wastewater contains a large number of Recyclable, with high value of pentosan, protein and other organic matter, but the wheat starch processing plant will rarely pay attention to it, most of them are discharged into the sewage treatment station, and some even direct emissions. This is not only a waste of resources, but also cause serious pollution to the environment of wastewater treatment. The traditional methods such as evaporation, biological treatment, chemical treatment such as high energy consumption, long process, high processing cost, causing relatively heavy economic burden to the enterprise. The high recovery value of wheat wastewater treatment and resource utilization of low cost is a common problem of the whole industry. In this paper, by using the method of direct separation membrane separation exchange chromatography protein precipitation, membrane separation / enzyme combination method, four ways of protein / membrane separation combined method for separation and recovery of high value of pentosan from wheat starch wastewater, respectively. Experimental study on the root. According to the experimental results of the four methods to make transverse comparison, engineering for the recovery of Pentosans in wheat starch wastewater using reference. In addition, the monosaccharide composition of pentosans on spectral identification, detection of the degree of branching of the polymer. Direct membrane separation experiments show that when the liquid through 100m L interception 700m L, 10000Dalton (hereinafter referred to as Da) ultrafiltration membrane on Pentosan retention rate reached 97.81%, the protein retention rate reached 97.75%, the retention of these two substances and through the liquid concentration ratio were 15.29 and 10.48, showed that 10000Da membrane has good retention capacity of these two substances. Retentate while reducing sugar and amino acids and the permeate concentration ratio close to 1 indicates that the 10000Da ultrafiltration membrane without interception ability of reducing sugar and amino acids. The ultrafiltration experiments were performed with 20000Da and 50000Da membrane experiment, the number of According to the retentate protein and pentosan and the permeate concentration ratio is close to 1, indicated that the two kinds of membrane protein and pentosan are no interception function. The experiments with protease hydrolysis, thermal coagulation, bio flocculant, isoelectric point precipitation method, three chloroacetic acid flocculation method, five methods of pre removal the protein in Wheat starch processing, to provide a prerequisite for membrane separation and recovery of pentosan. The experimental results show that the removal of proteins are different. The removal rate of protein is enzymatic (87.11%) three trichloroacetic acid method (68.50%) natural polymer flocculation (20.29%) thermal coagulation (17.51%) isoelectric point method (8.56%). At the same time, pentosan five processing methods of the loss rates were: three trichloroacetic acid method (22.89%) protein (12.93%) organic polymer flocculation (11.21%) thermal coagulation (9.16%) isoelectric point method (8.24%). The protein removal The rate and pentosan retention rate as evaluation index, and ultimately determine the solution method for protein protease. The protease method suitable for wastewater pretreatment after protein removal rate was 87.11%, only subsequent loss of 12.93%. pentosan by direct membrane separation method, using 10000Da membrane, basically can be pentosan interception and recovery. On the basis of above experiments the experimental design method, enzymolysis and membrane separation combined: first for the decomposition of protein amino acids and then 10000Da ultrafiltration membrane amino acid, reducing sugar and pentosan enzyme / ultrafiltration separately. Experimental results show that when the liquid reaches to be separated through 1.5 times the volume of fluid (replenishment cycle), the whole process of protein the total removal rate is 92.27%, the reducing sugar and amino acids (protein digests) the retention rate of only 24.16% and 28.10%, the total pentosan retention rate of 77.36%.10000Da ultrafiltration membrane on reducing sugar and eggs White matter after degradation products of amino acids without interception function. Therefore, the cycle number increases, prolong the time of ultrafiltration can achieve the removal of protein hydrolysate in wastewater (amino acids) and reducing sugar, interception effect. This paper tries to pentosan exchange chromatography separation recovery of pentosan. Using DEAE-52 cellulose chromatography as medium, using water as eluent to join the amount of Na Cl enhanced segment elution effect. The eluate was analyzed by using the freeze-thaw judgment separation effect, analysis of protein content by UV spectrophotometry, ion chromatography quantitative analysis of pentosan (including reducing sugar). At the same time, auxiliary analysis to determine the chemical structure of solid component eluting liquid using infrared spectroscopy experiments. The results show that the distribution curve of pentosan in full compliance with the elution separation law of typical operation conditions of chromatography, separation is successful, DEAE-52 cellulose resin suitable for The separation of pentosan, good separation effect. Freeze detection results proved the most liquid chromatography elution in soluble pentosan and thawing method and ultraviolet spectrophotometry, impurities substantially free of protein and amino acid. The infrared spectra of 917.12 cm - 1 - D - galactose appear beta pyranose characteristic peak, 841.12 cm 1 alpha - D - Grape pyranose peaks, showed that the polysaccharide has a glycosidic bond and beta glycosidic bond. The recovered pentosan into monosaccharide by acid hydrolysis by ion chromatography detection of monosaccharide sugar belonging. Test results show that the wheat starch waste water separated from the main pentosan by the Arabia sugar, xylose, galactose and glucose,.N composed of four monosaccharides (Ara) /n (Xyl) ratio was 0.92, reflecting the degree of branching polymer pentosan is relatively large. The overall evaluation, the separation of the four methods is selected, by enzymatic hydrolysis Membrane separation / combination method is better. The operation process is relatively simple, the separation rate is relatively high, the separation and recovery of pentosan can also further amino acids and reducing sugar. If the final can achieve industrialization, economic benefits should be relatively high, so the application prospect is expected better.

【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X792;TQ281

【参考文献】

中国期刊全文数据库 前10条

1 陈慧光,贺立敏,田颖,杨建伟;壳聚糖制备及其在渔业废水处理中的应用[J];大连铁道学院学报;1998年02期

2 周阳;刘芳;吕大鹏;;小麦淀粉废水处理综述[J];发酵科技通讯;2003年01期

3 黄慧,陈理;壳聚糖絮凝剂对粉丝废水的絮凝效果研究[J];广西轻工业;2003年03期

4 张振家,王太平,张虹,张扬;UASB反应器处理淀粉废水试验研究[J];工业水处理;2002年01期

5 刘秉涛,张焱,王海荣;壳聚糖对含蛋白废水的絮凝与回收[J];华北水利水电学院学报;2005年04期

6 张佩芳;倪哲明;;脱乙酰甲壳质处理含淀粉废水的试验[J];环境污染与防治;1990年03期

7 李为群,刘健,赵宇华;高分子絮凝剂开发应用新动向[J];环境污染与防治;1997年03期

8 贺晓红，杨志华，，祝万鹏;许昌淀粉厂废水处理站设计[J];给水排水;1997年03期

9 雷晓燕;利用淀粉厂废水生产单细胞蛋白的研究[J];辽宁化工;2005年04期

10 郑芸岭,徐玉佩;天然絮凝剂壳聚糖回收大豆蛋白的研究[J];粮食与油脂;1997年01期

中国硕士学位论文全文数据库 前1条

1 张梅红;小麦麸皮阿拉伯木聚糖的制备及益生活性研究[D];中国农业科学院;2013年

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