【摘要】：目前,污泥處理處置過程中面臨的一個(gè)主要問題就是污泥經(jīng)過常規(guī)調(diào)理、脫水之后,污泥的含水率仍高達(dá)80%,達(dá)不到后續(xù)處理處置要求。因此,污泥需要進(jìn)一步的深度脫水。然而,常用的污泥深度脫水藥劑不易降解,在解決污泥脫水的同時(shí)易帶來一些其它問題。本課題從完整的污泥處理角度考慮,旨在利用有機(jī)酸的易降解優(yōu)點(diǎn),將其對(duì)污泥進(jìn)行預(yù)處理以達(dá)到深度脫水的目的,使污泥含水率達(dá)到后續(xù)處理的要求。本課題有四部分的研究內(nèi)容:第一部分是幾種常見有機(jī)酸預(yù)處理污泥脫水效果對(duì)比。第二部分是有機(jī)酸預(yù)處理對(duì)泥餅重金屬及上清液TOC和TN的影響。第三部分是有機(jī)酸預(yù)處理過程對(duì)污泥深度脫水的影響。第四部分是有機(jī)酸預(yù)處理對(duì)污泥深度脫水的作用機(jī)理分析。具體研究結(jié)果如下:(1)污泥經(jīng)5種有機(jī)酸預(yù)處理之后,其深度脫水性能明顯改善。原始污泥脫水泥餅含水率仍高達(dá)80.2%,而經(jīng)過濃度為0.1mol/L-0.6mol/L的冰乙酸、乳酸、檸檬酸、草酸和酒石酸預(yù)處理,泥餅含水率降低至68.1%-75.5%。在這5種有機(jī)酸中,污泥經(jīng)過0.2mol/L的草酸和酒石酸預(yù)處理后,其脫水泥餅含水率較低,分別為68.1%和68.3%。(2)有機(jī)酸預(yù)處理,在改善污泥深度脫水的同時(shí),也能夠去除污泥中部分重金屬和增加上清液中的TOC和TN含量。污泥分別經(jīng)0.6mol/L的酒石酸和草酸預(yù)處理后,脫水泥餅中鋅去除率較高,鋅的最大去除率分別達(dá)到63.1%和72.1%;上清液中的TOC含量從49.8mg/L分別增加至27280mg/L和14970mg/L,TN含量從16.5mg/L分別增加至39.5mg/L和93.1mg/L。(3)在草酸投加量為最佳投加量的條件下,改變溫度、攪拌時(shí)間、攪拌速度后,污泥混合液pH值處在1.9-2.1,脫水泥餅含水率為59.2%-61.2%,溫度、攪拌時(shí)間、攪拌速度對(duì)污泥的可脫水程度影響不大。隨著草酸投加量的提高,污泥的沉降性能,泥餅含水率、C/N比和混合液pH值,以及上清液中的蛋白質(zhì)、多糖、TOC和TN含量、C/N比變化明顯。經(jīng)投加量為0.34g/g DS的草酸預(yù)處理,污泥90min的沉降率從11.3%升高至40.4%,脫水泥餅含水率從73.8%降低至59.2%,脫水泥餅C/N比從6.4提高至6.9,混合液pH值從7.0降低至2.1。污泥濃度在1.5%-9.5%范圍內(nèi),泥餅含水率從58.9%增大到76.3%,混合液pH值從1.7升高至4.7。(4)機(jī)理分析發(fā)現(xiàn),草酸與污泥顆粒表面電荷的吸附電中和起到主要作用,改善了污泥的深度脫水性能。當(dāng)草酸投加量為0g/g DS-0.57g/g DS時(shí),混合液pH從7.0降低至1.6,而Zeta電位從-13.2mV變化為+4.1mV;d50從54.6μm降低至50.1μm。從掃描電鏡圖可知,與原始污泥相比,污泥經(jīng)投加量為0.34g/g DS的草酸預(yù)處理后,污泥顆粒結(jié)構(gòu)變得非常致密,顆粒之間距離較近,污泥表面的EPS明顯減少。在草酸預(yù)處理過程中,污泥顆粒粒徑的減小對(duì)污泥脫水效果的影響不大。
[Abstract]:At present, one of the main problems in the process of sludge treatment and disposal is that the water content of sludge is still as high as 80% after dewatering, which can not meet the requirement of subsequent treatment and disposal. Therefore, the sludge needs further deep dewatering. However, the commonly used deep dewatering agent is not easy to degrade, and it is easy to bring some other problems while sludge dewatering. From the point of view of complete sludge treatment, the purpose of this paper is to make use of the advantages of organic acid to pre-treat sludge to achieve the purpose of deep dewatering, and to make the moisture content of sludge reach the requirement of subsequent treatment. This paper has four parts of research content: the first part is several common organic acid pretreatment sludge dewatering effect contrast. The second part is the effect of organic acid pretreatment on heavy metal and supernatant TOC and TN in mud cake. The third part is the effect of organic acid pretreatment on deep dewatering of sludge. The fourth part is the mechanism of organic acid pretreatment on deep dewatering of sludge. The results are as follows: (1) after pretreatment with five organic acids, the deep dehydration performance of sludge is improved obviously. The moisture content of the original sludge dewatered cake was still as high as 80.2%, but after pretreatment with acetic acid, lactic acid, citric acid, oxalic acid and tartaric acid at the concentration of 0.1mol/L-0.6mol/L, the moisture content of the mud cake decreased to 68.1% -75.5%. Among the five organic acids, sludge treated with oxalic acid and tartaric acid from 0.2mol/L had a lower moisture content of decement cake, which was 68.1% and 68.3%, respectively. (2) Organic acid pretreatment improved the deep dewatering of sludge at the same time. It can also remove some heavy metals in sludge and increase the content of TOC and TN in supernatant. After the sludge was pretreated with tartaric acid and oxalic acid from 0.6mol/L, the removal rate of zinc was higher, and the maximum removal rate of zinc reached 63.1% and 72.1% respectively. The content of TOC in supernatant increased from 49.8mg/L to 27280mg/L and 14970 mg / L N from 16.5mg/L to 39.5mg/L and 93.1 mg / L respectively. (3) under the optimum dosage of oxalic acid, After changing the temperature, stirring time and stirring speed, the pH value of sludge mixture was 1.9-2.1, and the moisture content of decement cake was 59.2-61.2.The temperature, stirring time and stirring speed had little effect on the dewatering degree of sludge. With the increase of oxalic acid dosage, sludge settling performance, water content of mud cake, C / N ratio and pH value of mixed solution, and the contents of protein, polysaccharide, TOC and TN in supernatant, C / N ratio changed obviously. After pretreatment with oxalic acid (0.34g/g DS), the sedimentation rate of sludge 90min increased from 11.3% to 40.4%, the moisture content of the decement cake decreased from 73.8% to 59.2%, and the C / N ratio increased from 6.4% to 6.9%. The pH value of the mixture decreased from 7.0 to 2.1. In the range of 1.5 ~ 9.5% sludge concentration, the moisture content of mud cake increased from 58.9% to 76.3%, and the pH value of mixed solution increased from 1.7% to 4.7%. (4) Mechanism analysis showed that, The adsorption and electroneutralization of oxalic acid and surface charge of sludge particles play a major role in improving the deep dewatering performance of sludge. When the dosage of oxalic acid was 0g/g DS-0.57g/g DS, the pH of the mixture decreased from 7.0 to 1.6, while the Zeta potential changed from -13.2mV to 4.1mV / d _ (50) from 54.6 渭 m to 50.1 渭 m. Compared with the original sludge, after pretreatment with oxalic acid with the dosage of 0.34g/g DS, the granular structure of the sludge became very compact, the distance between the particles was close, and the EPS on the surface of the sludge decreased obviously. In the process of oxalic acid pretreatment, the reduction of sludge particle size has little effect on sludge dewatering effect.
【學(xué)位授予單位】：河南工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：X703

【共引文獻(xiàn)】

相關(guān)期刊論文 前10條

1 羅鑫;林春綿;甄萬順;;典型污泥化學(xué)調(diào)理脫水實(shí)驗(yàn)研究[J];環(huán)境科學(xué)與技術(shù);2014年S1期

2 劉吉寶;魏源送;王亞煒;才興;邵春巖;;基于預(yù)處理的強(qiáng)化污泥脫水研究進(jìn)展[J];中國給水排水;2014年14期

3 顏金培;陳立奇;楊林軍;;燃煤細(xì)顆粒在過飽和氛圍下聲波團(tuán)聚脫除的實(shí)驗(yàn)研究[J];化工學(xué)報(bào);2014年08期

4 陳曦;喻可U，

本文編號(hào)：2390047