利用淋洗劑組合去除土壤中重金屬及淋洗液回收技術(shù)研究
發(fā)布時間：2018-10-13 14:12
【摘要】：本文以湖南郴州受多種重金屬污染土壤為研究對象,通過實驗室實驗,開展了一系列振蕩淋洗實驗,確定最佳淋洗劑、最佳淋洗條件、最佳淋洗組合。同時開展淋洗劑回收的研究工作,并且對淋洗后的土壤進(jìn)行發(fā)芽實驗,以驗證其生態(tài)毒性。從而為在更大范圍內(nèi)修復(fù)重金屬污染土壤儲備技術(shù)和經(jīng)驗。主要結(jié)論如下：(1)通過對采集土壤樣品的分析,該土壤中Cu、Zn、Pb、Cd、As的含量分別為46 mg·kg~(-1)243 mg·kg~(-1),322 mg·kg~(-1),1.32 mg·kg~(-1)、32 mg ·kg~(-1)。其中Cd污染最為嚴(yán)重,超過國家限定標(biāo)準(zhǔn)4.4倍,其次還伴隨有一定程度的Zn、Pb、As污染。(2)通過比較三種不同的EDTA鹽(Na-EDTA、NH4-EDTA、Ca-EDTA)對土壤的淋洗效果,結(jié)果表明,三種EDTA鹽對土壤中Cu、Zn、Pb、Cd都具有一定的淋洗效果,對As幾乎沒有去除效果,對不同重金屬的去除率表現(xiàn)為：CdPbCuZnAs,對同一重金屬,三種鹽在淋洗能力上表現(xiàn)為NH4-EDTA Na-EDTA Ca-EDTA.(3)對Na-EDTA、NH4-EDTA、Ca-EDTA的淋洗液濁度進(jìn)行測定,其濁度分別為35NTU、33NTU、2.5NTU,Ca-EDTA淋洗液具有沉降性更好的優(yōu)勢,考慮到后續(xù)處理的方便程度,采用Ca-EDTA為所選淋洗劑。(4)Ca-EDTA的最佳淋洗條件為：濃度25 mmol·L~(-1),固液比1：5,淋洗時間2h,連續(xù)淋洗3次,在該條件下累計可以去除土壤中26.30%的Cu、12.37%的Zn、45.18%的Pb、73.28%的Cd。(5)考慮到Ca-EDTA對As幾乎沒有去除效果,我們引入Ca-EDTA+草酸、Ca-EDTA+磷酸氫二鉀的淋洗劑組合實驗,結(jié)果表明,磷酸氫二鉀對As去除效果較差,草酸對As去除效果較好,同時對Cu、Zn、Pb、Cd還有一定去除能力,經(jīng)過Ca-EDTA連續(xù)淋洗3次,草酸連續(xù)淋洗2次,可以累積去除土壤中42.49%的Cu、21.98%的Zn、44.21%的Pb、83.46%的Cd、17.74%的As,淋洗后土壤中各重金屬指標(biāo)均低于國家土壤環(huán)境質(zhì)量標(biāo)準(zhǔn)中的重金屬限定值的二級標(biāo)準(zhǔn)�？紤]到EDTA的難降解性,建議先用EDTA再用草酸的淋洗順序。(6)利用Na_2S溶液對EDTA淋洗液進(jìn)行處理,結(jié)果表明：Na_2S的投加量為3mmol時,Cu、Zn、Pb、 Cd的去除率均達(dá)到100%。EDTA淋洗液在經(jīng)過Na_2S處理后,其回收的EDTA溶液對土壤重金屬仍有一定的去除能力,但其效能下降了約30%。(7)氯型陰離子交換樹脂對淋洗液中的重金屬具有較好的吸附效果,在固液比為1：20的條件下,對淋洗液中Cu、Zn、Pb、Cd的去除率分別為：100%、74%、96%、95%。樹脂可以再生,再生后的樹脂對淋洗液中Cu、Zn、Pb、Cd的去除率分別為95.65%、74.56%、99.69%、100%。(8)通過對淋洗后的土壤進(jìn)行紫云英的發(fā)芽實驗,結(jié)果表明,經(jīng)過淋洗后,土壤對紫云英的發(fā)芽狀況有一定的抑制作用,因為土壤中的營養(yǎng)元素在淋洗過程中也發(fā)生了流失,通過添加有機(jī)肥、復(fù)合肥,能使肥力得到一定程度的恢復(fù),有利于增加紫云英發(fā)芽率。
[Abstract]:In this paper, a series of oscillatory elution experiments were carried out in Chenzhou, Hunan Province, by means of laboratory experiments. The best eluent, the best leaching conditions and the best elution combination were determined. At the same time, the study on the recovery of eluent was carried out, and the germinating experiment was carried out on the eluted soil to verify its ecological toxicity. So as to remediate the heavy metal contaminated soil storage technology and experience in a wider range. The main conclusions are as follows: (1) the contents of Cu,Zn,Pb,Cd,As in the soil were 46 mg kg~ (-1) 243 mg kg~ (-1), 322 mg kg~ (-1), 1.32 mg kg~ (-1), 32 mg kg~ (-1), respectively. Cd pollution was the most serious, 4.4 times higher than the national standard, followed by a certain degree of Zn,Pb,As pollution. (2) the leaching effect of three different EDTA salts (Na-EDTA,NH4-EDTA,Ca-EDTA) on soil was compared. The three kinds of EDTA salts had a certain leaching effect on Cu,Zn,Pb,Cd in soil, but had little effect on As removal. The removal rates of different heavy metals were as follows: CdPbCuZnAs, for the same heavy metal. The elution ability of the three salts was as follows: NH4-EDTA Na-EDTA Ca-EDTA. (3) was used to determine the turbidity of the eluent of Na-EDTA,NH4-EDTA,Ca-EDTA. The turbidity of the eluent was 35NTUU33NTU2.5NTU2.5NTU2.5NTUU2.5NTa-EDTA, which had the advantage of better sedimentation, taking into account the convenience of subsequent treatment. Ca-EDTA was used as the eluent. (4) the optimum elution conditions of Ca-EDTA were as follows: concentration 25 mmol L ~ (-1), solid / liquid ratio 1: 5, elution time 2 h, continuous elution 3 times. Under this condition, the Cd. (5) of Pb,73.28% of Zn,45.18% of 26.30% of Cu,12.37% in soil could be removed. Considering that Ca-EDTA had little effect on As removal, we introduced Ca-EDTA oxalic acid and Ca-EDTA dipotassium hydrogen phosphate into the eluent combination experiment, the results showed that, The effect of potassium hydrogen phosphate on As removal was poor, oxalic acid on As removal was better, and there was a certain removal ability on Cu,Zn,Pb,Cd. After 3 consecutive Ca-EDTA elution, oxalic acid was eluted twice. 42.49% of Cu,21.98% can be removed from soil by the As, elution of Pb,83.46% Cd,17.74% of Zn,44.21%. The indexes of heavy metals in the soil are lower than the second grade standard of the limited value of heavy metals in the national soil environmental quality standard. Considering the difficult degradability of EDTA, it is suggested that the elution sequence of EDTA and oxalic acid should be used first. (6) the eluent of EDTA is treated with Na_2S solution. The results show that when the dosage of Na_2S is 3mmol, the removal rate of Cu,Zn,Pb, Cd can reach that of 100%.EDTA eluent after Na_2S treatment. The recovered EDTA solution still has some removal ability to heavy metals in soil, but its efficiency has decreased by about 30%. (7) chlorine anion exchange resin has a better adsorption effect on heavy metals in eluent, and the ratio of solid to liquid is 1:20. The removal rates of Cu,Zn,Pb,Cd in the eluate were as follows: 100%, 96% and 95%, respectively. The resin can be regenerated. The removal rate of Cu,Zn,Pb,Cd in the eluate by the regenerated resin is 95.65 ~ 74.56 and 99.6969 / 100 respectively. (8) through the experiment on the germination of purple cloud in the eluted soil, the results show that, after leaching, The soil has a certain inhibitory effect on the germination of Astragalus sinensis, because the nutrient elements in the soil have also been lost during the leaching process. By adding organic fertilizer and compound fertilizer, the fertility can be restored to a certain extent. It is beneficial to increase the germination rate of Ziyunxin.
【學(xué)位授予單位】：湖南農(nóng)業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：X53
本文編號：2268918
[Abstract]:In this paper, a series of oscillatory elution experiments were carried out in Chenzhou, Hunan Province, by means of laboratory experiments. The best eluent, the best leaching conditions and the best elution combination were determined. At the same time, the study on the recovery of eluent was carried out, and the germinating experiment was carried out on the eluted soil to verify its ecological toxicity. So as to remediate the heavy metal contaminated soil storage technology and experience in a wider range. The main conclusions are as follows: (1) the contents of Cu,Zn,Pb,Cd,As in the soil were 46 mg kg~ (-1) 243 mg kg~ (-1), 322 mg kg~ (-1), 1.32 mg kg~ (-1), 32 mg kg~ (-1), respectively. Cd pollution was the most serious, 4.4 times higher than the national standard, followed by a certain degree of Zn,Pb,As pollution. (2) the leaching effect of three different EDTA salts (Na-EDTA,NH4-EDTA,Ca-EDTA) on soil was compared. The three kinds of EDTA salts had a certain leaching effect on Cu,Zn,Pb,Cd in soil, but had little effect on As removal. The removal rates of different heavy metals were as follows: CdPbCuZnAs, for the same heavy metal. The elution ability of the three salts was as follows: NH4-EDTA Na-EDTA Ca-EDTA. (3) was used to determine the turbidity of the eluent of Na-EDTA,NH4-EDTA,Ca-EDTA. The turbidity of the eluent was 35NTUU33NTU2.5NTU2.5NTU2.5NTUU2.5NTa-EDTA, which had the advantage of better sedimentation, taking into account the convenience of subsequent treatment. Ca-EDTA was used as the eluent. (4) the optimum elution conditions of Ca-EDTA were as follows: concentration 25 mmol L ~ (-1), solid / liquid ratio 1: 5, elution time 2 h, continuous elution 3 times. Under this condition, the Cd. (5) of Pb,73.28% of Zn,45.18% of 26.30% of Cu,12.37% in soil could be removed. Considering that Ca-EDTA had little effect on As removal, we introduced Ca-EDTA oxalic acid and Ca-EDTA dipotassium hydrogen phosphate into the eluent combination experiment, the results showed that, The effect of potassium hydrogen phosphate on As removal was poor, oxalic acid on As removal was better, and there was a certain removal ability on Cu,Zn,Pb,Cd. After 3 consecutive Ca-EDTA elution, oxalic acid was eluted twice. 42.49% of Cu,21.98% can be removed from soil by the As, elution of Pb,83.46% Cd,17.74% of Zn,44.21%. The indexes of heavy metals in the soil are lower than the second grade standard of the limited value of heavy metals in the national soil environmental quality standard. Considering the difficult degradability of EDTA, it is suggested that the elution sequence of EDTA and oxalic acid should be used first. (6) the eluent of EDTA is treated with Na_2S solution. The results show that when the dosage of Na_2S is 3mmol, the removal rate of Cu,Zn,Pb, Cd can reach that of 100%.EDTA eluent after Na_2S treatment. The recovered EDTA solution still has some removal ability to heavy metals in soil, but its efficiency has decreased by about 30%. (7) chlorine anion exchange resin has a better adsorption effect on heavy metals in eluent, and the ratio of solid to liquid is 1:20. The removal rates of Cu,Zn,Pb,Cd in the eluate were as follows: 100%, 96% and 95%, respectively. The resin can be regenerated. The removal rate of Cu,Zn,Pb,Cd in the eluate by the regenerated resin is 95.65 ~ 74.56 and 99.6969 / 100 respectively. (8) through the experiment on the germination of purple cloud in the eluted soil, the results show that, after leaching, The soil has a certain inhibitory effect on the germination of Astragalus sinensis, because the nutrient elements in the soil have also been lost during the leaching process. By adding organic fertilizer and compound fertilizer, the fertility can be restored to a certain extent. It is beneficial to increase the germination rate of Ziyunxin.
【學(xué)位授予單位】：湖南農(nóng)業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：X53
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 孫濤;陸扣萍;王海龍;;不同淋洗劑和淋洗條件下重金屬污染土壤淋洗修復(fù)研究進(jìn)展[J];浙江農(nóng)林大學(xué)學(xué)報;2015年01期
2 黃園英;王倩;劉斯文;袁欣;;納米鐵快速去除地下水中多種重金屬研究[J];生態(tài)環(huán)境學(xué)報;2014年05期
3 陳印軍;楊俊彥;方琳娜;;我國耕地土壤環(huán)境質(zhì)量狀況分析[J];中國農(nóng)業(yè)科技導(dǎo)報;2014年02期
4 王金成;周天林;井明博;劉建新;楊建霞;;隴東黃土高原地區(qū)石油污泥原位修復(fù)過程中土壤主要肥力指標(biāo)動態(tài)變化分析[J];環(huán)境科學(xué)學(xué)報;2015年01期
5 王磊;龍濤;張峰;祝欣;田猛;林玉鎖;;用于土壤及地下水修復(fù)的多相抽提技術(shù)研究進(jìn)展[J];生態(tài)與農(nóng)村環(huán)境學(xué)報;2014年02期
6 張建榮;李娟;許偉;;原位生物穩(wěn)定固化技術(shù)在鉻污染場地治理中的應(yīng)用研究[J];環(huán)境科學(xué);2013年09期
7 易龍生;王文燕;陶冶;劉陽;溫建;肖娟;;有機(jī)酸對污染土壤重金屬的淋洗效果研究[J];農(nóng)業(yè)環(huán)境科學(xué)學(xué)報;2013年04期
8 趙金艷;李瑩;李珊珊;張爽;;我國污染土壤修復(fù)技術(shù)及產(chǎn)業(yè)現(xiàn)狀[J];中國環(huán)保產(chǎn)業(yè);2013年03期
9 黃益宗;郝曉偉;雷鳴;鐵柏清;;重金屬污染土壤修復(fù)技術(shù)及其修復(fù)實踐[J];農(nóng)業(yè)環(huán)境科學(xué)學(xué)報;2013年03期
10 張艷杰;魯順保;彭桂群;;陰極pH控制對電動去除電鍍污泥重金屬的影響[J];環(huán)境化學(xué);2013年03期
相關(guān)碩士學(xué)位論文 前1條
1 房劍紅;重金屬污染濱海鹽漬土壤淋洗改良研究[D];暨南大學(xué);2007年
，本文編號：2268918
本文鏈接：http://sikaile.net/kejilunwen/huanjinggongchenglunwen/2268918.html
最近更新
教材專著
