【摘要】：垃圾填埋場產(chǎn)生的有毒性滲濾液和填埋氣對填埋場底部、填埋場周邊土壤和大氣環(huán)境造成了很大的威脅。國內(nèi)外研究成果表明即使填埋場建造了標(biāo)準(zhǔn)的防滲系統(tǒng),仍有相當(dāng)多的場地對地下水、周圍土體和大氣環(huán)境造成了污染。 本文在國家自然科學(xué)基金面上項(xiàng)目“垃圾填埋場覆蓋屏障氣體運(yùn)移特性與長期服役性能評價(jià)方法”和國家自然科學(xué)基金青年基金項(xiàng)目“垃圾填埋場復(fù)合襯墊在高應(yīng)力和高水頭作用下的防污性能研究”、973計(jì)劃“填埋場服役性能模擬、災(zāi)害評價(jià)及可持續(xù)防控”、國家自然科學(xué)基金重大國際合作項(xiàng)目“城市垃圾填埋場水氣產(chǎn)生、運(yùn)移及系統(tǒng)化工程控制”和浙江省公益性技術(shù)應(yīng)用研究計(jì)劃項(xiàng)目“垃圾填埋場復(fù)合襯墊長期性能的離心模型試驗(yàn)與污染防控技術(shù)”的基礎(chǔ)上研究了填埋場屏障系統(tǒng)服役性能的評價(jià)方法。本文首先對國內(nèi)外填埋場滲濾液和填埋氣污染物遷移機(jī)理及影響因素進(jìn)行了匯總和分析。在此基礎(chǔ)上通過提出的解析方法和數(shù)值方法分析了填埋場飽和與非飽和襯墊系統(tǒng)和覆蓋層系統(tǒng)中滲濾液及填埋氣的運(yùn)移問題。探討了不同類型襯墊系統(tǒng)和覆蓋層系統(tǒng)的有效性。最后在國內(nèi)外對填埋場現(xiàn)場試驗(yàn)研究的成果上,針對淮南填埋場進(jìn)行了現(xiàn)場試驗(yàn)研究并給出填埋場現(xiàn)場分析的定量方法。本文所做工作及相應(yīng)的研究成果如下： (1)分別比較了國內(nèi)外對填埋場底部襯墊系統(tǒng)及頂部覆蓋層系統(tǒng)的組成差別及設(shè)計(jì)標(biāo)準(zhǔn)。對國內(nèi)外填埋場滲濾液和填埋氣的性質(zhì)及國內(nèi)外文獻(xiàn)報(bào)道的滲濾液和填埋氣主要污染物在填埋場土層中的環(huán)境土工參數(shù)進(jìn)行了匯總和統(tǒng)計(jì)分析,給出了這些參數(shù)的設(shè)計(jì)取值范圍; (2)由于固體垃圾中很大部分都是有機(jī)污染物,有機(jī)污染物的降解作用很重要。結(jié)合一階降解理論,并在此基礎(chǔ)上針對國內(nèi)襯墊系統(tǒng)中土工聚合粘土墊(GCL)+衰減層(AL)復(fù)合襯墊系統(tǒng),首次給出了考慮降解作用下污染物在GCL+AL復(fù)合襯墊系統(tǒng)的一維解析解。研究結(jié)果表明,如果GCL半衰期小于1年,在預(yù)測GCL+AL系統(tǒng)中有機(jī)污染物遷移時(shí)可以忽略GCL中有機(jī)物的降解作用； (3)結(jié)合非飽和單層土中含水量線性分布,得到了污染物在非飽和襯墊土層中的一維擴(kuò)散解析解。該解析解簡單方便,并能考慮含水量線性變化時(shí)污染物的擴(kuò)散問題,同時(shí)指出非飽和問題對污染物濃度變化的影響； (4)分析了國內(nèi)外填埋場設(shè)計(jì)中用于控制填埋氣釋放的覆蓋層系統(tǒng)組成。建立了飽和覆蓋層中填埋氣的一維擴(kuò)散模型,模型考慮了隨時(shí)間變化的氣體濃度邊界�；诜瓶硕杉熬�性方程的疊加原理,得到了氣體污染物通過飽和復(fù)合覆蓋層的一維擴(kuò)散解析解,在此基礎(chǔ)上比較了國內(nèi)不同類型覆蓋層系統(tǒng)對填埋氣控制性能的有效性,可以有效地應(yīng)用于基于性能的填埋場復(fù)合覆蓋層系統(tǒng)的初步設(shè)計(jì)； (5)對于國內(nèi)覆蓋層系統(tǒng)類型,飽和情況下GM+GCL、CCL、GM+CCL對氣體擴(kuò)散的控制性能依次減弱。對于GM/GCL,GCL含水飽和度從0.85增加到1時(shí),覆蓋層頂部通量減小了82.5%。飽和時(shí)GM/GCL系統(tǒng)頂部氣體達(dá)到穩(wěn)態(tài)的時(shí)間是非飽和情況下的約100倍。對于GM/CCL, CCL含水飽和度從0.1增加到0.85時(shí),覆蓋層頂部通量減小了近1個(gè)數(shù)量級； (6)針對垃圾填埋場內(nèi)部生物降解產(chǎn)生的氣體(以甲烷為主)和氧氣等在非飽和覆蓋層中的運(yùn)移問題,建立了氣體在成層非飽和覆蓋層中的一維擴(kuò)散模型。模型考慮了覆蓋層含水量瞬態(tài)變化和氣體擴(kuò)散的耦合作用。對于lm厚的覆蓋層,氣體運(yùn)移20d到100d時(shí),禍合含水量瞬態(tài)變化時(shí)得到的氣體相對濃度較含水量穩(wěn)態(tài)變化時(shí)得到的濃度小近8倍。并總結(jié)了非飽和土中氣體擴(kuò)散系數(shù)變化的經(jīng)驗(yàn)公式,比較得到不同氣體擴(kuò)散系數(shù)形式對禍合結(jié)果有較大影響; (7)根據(jù)國外對覆蓋層頂部大氣壓強(qiáng)實(shí)測數(shù)據(jù)的基礎(chǔ)上,擬合得到壓強(qiáng)的變化規(guī)律,并提出了大氣壓強(qiáng)對填埋氣運(yùn)移作用明顯時(shí)壓強(qiáng)波動幅度的取值范圍,對實(shí)際填埋場區(qū)域壓強(qiáng)波動對氣體控制的研究有很好的參考作用； (8)最后借助于對填埋場污染物的研究理論和分析方法研究了國內(nèi)淮南某垃圾填埋場污染物的現(xiàn)場運(yùn)移特性,給出了在成層粘土層中污染物運(yùn)移及預(yù)測的分析方法。現(xiàn)場試驗(yàn)表明17年后,Cl-在填埋場底土中的運(yùn)移深度已經(jīng)達(dá)到了底土下部的老粘土層;COD的運(yùn)移深度則在3m左右。將一維對流擴(kuò)散理論與實(shí)測結(jié)果的比較可知對流彌散作用對于污染物的運(yùn)移較為重要；以地表面為接觸面得到擬合結(jié)果不能很好地表示實(shí)際污染物的運(yùn)移,參考前人研究成果研究了有效接觸面問題。最佳的擬合結(jié)果得到的有效接觸面為地表面之上50cm。將一維對流-彌散解析解與實(shí)測數(shù)據(jù)的擬合比較則可得到粘土層相關(guān)運(yùn)移參數(shù)的取值范圍,可為污染物進(jìn)一步運(yùn)移提供依據(jù)。
[Abstract]:Toxic leachate and landfill gas produced by landfills pose a great threat to the bottom of landfills, the soil and atmospheric environment around landfills.
In this paper, the National Natural Science Foundation of China (NSFC) project "Evaluation Method of Gas Transport Characteristics and Long-term Service Performance of Landfill Cover Barrier" and the National Natural Science Foundation of China (NSFC) Youth Foundation of China (NSFC) project "Study on the Antifouling Performance of Composite Liner of Landfill under High Stress and High Water Head" are presented. Planning, Disaster Assessment and Sustainable Prevention and Control, Major International Cooperation Project of National Natural Science Foundation of China, Water and Gas Generation, Transportation and Systematic Engineering Control of Municipal Waste Landfills, and Research Program of Zhejiang Provincial Public Welfare Technology Application, Centrifugal Model Test of Long-term Performance and Pollution Prevention and Control Technology of Composite Liner of Waste Landfills Based on this, the evaluation method of landfill barrier system service performance is studied. In this paper, the migration mechanism and influencing factors of landfill leachate and landfill gas pollutants at home and abroad are summarized and analyzed. The migration of leachate and landfill gas in the system is discussed. The effectiveness of different types of liner systems and overlay systems is discussed. Finally, on the basis of the results of field tests at home and abroad, the field tests of Huainan landfill are carried out and the quantitative methods of field analysis are given. The results are as follows:
(1) Comparing the composition differences and design standards of landfill bottom liner system and top cover system at home and abroad, the characteristics of landfill leachate and landfill gas at home and abroad, and the environmental geotechnical parameters of major pollutants in landfill soil were summarized and statistically analyzed. The design range of these parameters is given.
(2) Because most of the solid waste is organic pollutants, the degradation of organic pollutants is very important. Based on the first-order degradation theory, the GCL+AL composite liner system considering the degradation of pollutants in the domestic liner system is proposed for the first time. The results show that if the half-life of GCL is less than one year, the degradation of organic compounds in GCL can be neglected in predicting the migration of organic pollutants in GCL + AL system.
(3) Combined with the linear distribution of water content in unsaturated monolayer soil, the analytical solution of one-dimensional diffusion of pollutants in unsaturated liner soil is obtained.
(4) The composition of landfill cover system used to control landfill gas release in landfill design at home and abroad is analyzed. A one-dimensional diffusion model of landfill gas in saturated cover is established, which takes into account the time-varying gas concentration boundary. On the basis of the analytical solution of one-dimensional diffusion of layers, the effectiveness of different types of landfill systems on the control performance of landfill gas is compared, which can be effectively applied to the preliminary design of performance-based landfill composite cover system.
(5) For the types of domestic overburden systems, the control performance of GM+GCL, CCL and GM+CCL on gas diffusion decreases in turn under saturation. For GM/GCL, when the water saturation of GCL increases from 0.85 to 1, the flux at the top of the overburden decreases by 82.5%. The time when the gas at the top of the GM/GCL system reaches steady state at saturation is about 100 times that under unsaturation. When L and CCL water saturation increased from 0.1 to 0.85, the flux at the top of the overburden decreased by almost 1 orders of magnitude.
(6) A one-dimensional gas diffusion model in layered unsaturated overburden was established for the transport of gases (mainly methane) and oxygen produced by biodegradation in landfill. The coupling effect of transient change of water content and gas diffusion in the overburden was considered. For lm-thick overburden, the gas diffusion was considered. The relative concentration of gases in the transient change of the combined water content is about 8 times less than that in the steady state change of the water content at 20 to 100 days of migration.
(7) Based on the measured data of atmospheric pressure at the top of the overburden abroad, the variation law of pressure is fitted and the range of pressure fluctuation amplitude when atmospheric pressure has obvious effect on landfill gas migration is put forward, which has a good reference for the study of pressure fluctuation in the actual landfill area on gas control.
(8) Finally, with the help of the theory and analysis method of pollutants in landfill site, the characteristics of pollutants migration in a landfill site in Huainan were studied, and the analysis method of pollutants migration and prediction in layered clay layer was given. Comparing the one-dimensional convection-diffusion theory with the measured results, it can be seen that the convection-dispersion effect is more important for the transport of pollutants; the fitting result with the surface as the contact surface can not well represent the actual transport of pollutants, and the effective contact is studied by referring to the previous research results. The best fitting results show that the effective contact surface is 50 cm above the surface. Comparing the one-dimensional analytical solution of convection-dispersion with the measured data, the range of the relevant transport parameters of clay layer can be obtained, which can provide a basis for further transport of pollutants.
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2013
【分類號】：X705;TU993.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 郭永龍,王焰新,蔡鶴生,劉紅濤,蔡志杰;垃圾填埋場滲濾液對地下水環(huán)境影響的評價(jià)[J];地質(zhì)科技情報(bào);2002年01期

2 李紅霞;何少華;袁華山;高偉;鳳迎春;;膨潤土對廢水中有機(jī)污染物的吸附[J];礦業(yè)工程;2006年04期

3 錢學(xué)德,施建勇,郭志平,呂進(jìn);粘土襯墊系統(tǒng)污染物遷移規(guī)律研究[J];河海大學(xué)學(xué)報(bào)(自然科學(xué)版);2004年04期

4 王超，阮曉紅，朱亮;污染物在非飽和土壤中遷移規(guī)律的試驗(yàn)研究[J];河海大學(xué)學(xué)報(bào);1996年02期

5 劉可卿;陳澤智;劉鵬;許雪松;唐秋萍;;南京市某垃圾填埋場重金屬污染現(xiàn)狀調(diào)查[J];環(huán)境監(jiān)測管理與技術(shù);2008年04期

6 馬志飛;安達(dá);姜永海;席北斗;李定龍;張進(jìn)保;楊昱;;某危險(xiǎn)廢物填埋場地下水污染預(yù)測及控制模擬[J];環(huán)境科學(xué);2012年01期

7 田揚(yáng)捷,黃仁華,楊虹,周海燕,李道棠;海濱垃圾填埋場滲瀝液對地下水系統(tǒng)的污染[J];環(huán)境衛(wèi)生工程;2005年01期

8 陳家軍,王紅旗,王金生,聶永豐,李國鼎;填埋場釋放氣體運(yùn)移數(shù)值模型及應(yīng)用[J];環(huán)境科學(xué)學(xué)報(bào);2000年03期

9 彭緒亞,余毅;填埋垃圾體氣體滲透特性的實(shí)驗(yàn)研究[J];環(huán)境科學(xué)學(xué)報(bào);2003年04期

10 謝海建;柯瀚;陳云敏;;濃度變化時(shí)復(fù)合襯層中有機(jī)污染物的一維擴(kuò)散分析[J];環(huán)境科學(xué)學(xué)報(bào);2006年06期

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