CAJ | 학술논문

【目的】沼液含有丰富养分元素和生理活性物质，沼液灌溉不仅能消纳沼液，同时也可促进植物生长。但是在经济利益的驱使下，某些重金属元素由于人为的添加，不可避免地通过饲料—畜禽—粪便途径进入沼气发酵池，导致用沼液灌溉后土壤中重金属含量的超标。本文通过对不同沼气发酵规模和不同地区的沼液中重金属元素含量的分析，并对其污染风险进行评估，探索沼液灌溉的风险等级，以期为选择灌溉前对沼液的处理方法提供依据。【方法】采用文献调研与样品分析，对比分析全国部分地区户用沼气池沼液和沼气工程沼液中的重金属元素含量，收集和监测了全国部分地区户用沼气池和沼气工程近100个沼液样品的重金属含量数据，其中镉（ Cd）、铬（ Cr）和铅（ Pb）采用原子吸收分光光度法，砷（ As）采用二乙基二硫代氨基甲酸银分光光度法，汞（ Hg）采用冷原子吸收光谱法测定。采用不同风险表征指数（算术均值指数、几何均值指数、Nemerrow指数、单位向量指数）评估重金属的风险等级。【结果】1）搜集的户用沼液和沼气工程沼液中重金属数据均不符合正态分布，户用沼液中As、Cd、Cr、Hg和Pb含量的中位值分别为0.312、0.0195、0.183、0.025和0.330 mg/L，沼气工程沼液分别为0.110、0.009、0.218、0.004和0.131 mg/L。除As外，后者平均含量明显高于前者。户用沼液中Cd、Hg属高强度变异，As、Cr和Pb属中度变异，而工程沼液中各重金属变异系数均属高强度变异。2）不同原料沼液重金属含量差异较大，其中猪场沼液重金属含量均高于牛场，风险相对较大。3）采用综合风险指数评价，户用沼液中Pb、As的单位向量指数评价，属于低风险，其余重金属的各指标均小于0.2，无风险。工程沼液中Hg的算术均值指数、几何均值指数、Nemerrow指数、单位向量指数均最高，按Nemerrow指数计算，工程沼液中Hg属较高风险，按均值指数和单位向量指数计算，Hg属于低风险等级。Cd的Nemerrow指数评价，属低风险，其余重金属的综合风险指数虽然随计算方法不同而变化，但其风险等级一致，均属于无风险。4）调查地区中，河南、安徽的工程沼液中重金属的Nemerrow风险指数最大，属于较高风险，因此其沼液除了必要的物理处理外，还需利用化学方法进行处理，降低风险后才可进行灌溉；其次湖南、浙江，属于低风险，这些地区沼液只需物理处理和简单化学处理后便可灌溉；其余地区Nemerrow风险指数评价，属于无风险等级。此外，内蒙古、辽宁、福建、四川和重庆5个地区的户用沼液中重金属的Nemerrow风险指数均低于0.2，属于无风险状态，只需经过简单的物理处理便可直接进行灌溉。【结论】统计分析表明，沼液灌溉存在一定风险，主要发酵原料对沼液中重金属含量的影响较大，地域对沼液灌溉风险虽有一定影响，但南方片区与北方片区工程沼液重金属风险等级并没有显著性差异。户用沼气池沼液和沼气工程沼液中，含量相对较低的Hg、Cd风险反而较大，建议在灌溉前通过化学方法予以去除。【目的】沼液含有豐富養分元素和生理活性物質，沼液灌溉不僅能消納沼液，同時也可促進植物生長。但是在經濟利益的驅使下，某些重金屬元素由于人為的添加，不可避免地通過飼料—畜禽—糞便途徑進入沼氣髮酵池，導緻用沼液灌溉後土壤中重金屬含量的超標。本文通過對不同沼氣髮酵規模和不同地區的沼液中重金屬元素含量的分析，併對其汙染風險進行評估，探索沼液灌溉的風險等級，以期為選擇灌溉前對沼液的處理方法提供依據。【方法】採用文獻調研與樣品分析，對比分析全國部分地區戶用沼氣池沼液和沼氣工程沼液中的重金屬元素含量，收集和鑑測瞭全國部分地區戶用沼氣池和沼氣工程近100箇沼液樣品的重金屬含量數據，其中鎘（ Cd）、鉻（ Cr）和鉛（ Pb）採用原子吸收分光光度法，砷（ As）採用二乙基二硫代氨基甲痠銀分光光度法，汞（ Hg）採用冷原子吸收光譜法測定。採用不同風險錶徵指數（算術均值指數、幾何均值指數、Nemerrow指數、單位嚮量指數）評估重金屬的風險等級。【結果】1）搜集的戶用沼液和沼氣工程沼液中重金屬數據均不符閤正態分佈，戶用沼液中As、Cd、Cr、Hg和Pb含量的中位值分彆為0.312、0.0195、0.183、0.025和0.330 mg/L，沼氣工程沼液分彆為0.110、0.009、0.218、0.004和0.131 mg/L。除As外，後者平均含量明顯高于前者。戶用沼液中Cd、Hg屬高彊度變異，As、Cr和Pb屬中度變異，而工程沼液中各重金屬變異繫數均屬高彊度變異。2）不同原料沼液重金屬含量差異較大，其中豬場沼液重金屬含量均高于牛場，風險相對較大。3）採用綜閤風險指數評價，戶用沼液中Pb、As的單位嚮量指數評價，屬于低風險，其餘重金屬的各指標均小于0.2，無風險。工程沼液中Hg的算術均值指數、幾何均值指數、Nemerrow指數、單位嚮量指數均最高，按Nemerrow指數計算，工程沼液中Hg屬較高風險，按均值指數和單位嚮量指數計算，Hg屬于低風險等級。Cd的Nemerrow指數評價，屬低風險，其餘重金屬的綜閤風險指數雖然隨計算方法不同而變化，但其風險等級一緻，均屬于無風險。4）調查地區中，河南、安徽的工程沼液中重金屬的Nemerrow風險指數最大，屬于較高風險，因此其沼液除瞭必要的物理處理外，還需利用化學方法進行處理，降低風險後纔可進行灌溉；其次湖南、浙江，屬于低風險，這些地區沼液隻需物理處理和簡單化學處理後便可灌溉；其餘地區Nemerrow風險指數評價，屬于無風險等級。此外，內矇古、遼寧、福建、四川和重慶5箇地區的戶用沼液中重金屬的Nemerrow風險指數均低于0.2，屬于無風險狀態，隻需經過簡單的物理處理便可直接進行灌溉。【結論】統計分析錶明，沼液灌溉存在一定風險，主要髮酵原料對沼液中重金屬含量的影響較大，地域對沼液灌溉風險雖有一定影響，但南方片區與北方片區工程沼液重金屬風險等級併沒有顯著性差異。戶用沼氣池沼液和沼氣工程沼液中，含量相對較低的Hg、Cd風險反而較大，建議在灌溉前通過化學方法予以去除。
【목적】소액함유봉부양분원소화생리활성물질，소액관개불부능소납소액，동시야가촉진식물생장。단시재경제이익적구사하，모사중금속원소유우인위적첨가，불가피면지통과사료—축금—분편도경진입소기발효지，도치용소액관개후토양중중금속함량적초표。본문통과대불동소기발효규모화불동지구적소액중중금속원소함량적분석，병대기오염풍험진행평고，탐색소액관개적풍험등급，이기위선택관개전대소액적처리방법제공의거。【방법】채용문헌조연여양품분석，대비분석전국부분지구호용소기지소액화소기공정소액중적중금속원소함량，수집화감측료전국부분지구호용소기지화소기공정근100개소액양품적중금속함량수거，기중력（ Cd）、락（ Cr）화연（ Pb）채용원자흡수분광광도법，신（ As）채용이을기이류대안기갑산은분광광도법，홍（ Hg）채용랭원자흡수광보법측정。채용불동풍험표정지수（산술균치지수、궤하균치지수、Nemerrow지수、단위향량지수）평고중금속적풍험등급。【결과】1）수집적호용소액화소기공정소액중중금속수거균불부합정태분포，호용소액중As、Cd、Cr、Hg화Pb함량적중위치분별위0.312、0.0195、0.183、0.025화0.330 mg/L，소기공정소액분별위0.110、0.009、0.218、0.004화0.131 mg/L。제As외，후자평균함량명현고우전자。호용소액중Cd、Hg속고강도변이，As、Cr화Pb속중도변이，이공정소액중각중금속변이계수균속고강도변이。2）불동원료소액중금속함량차이교대，기중저장소액중금속함량균고우우장，풍험상대교대。3）채용종합풍험지수평개，호용소액중Pb、As적단위향량지수평개，속우저풍험，기여중금속적각지표균소우0.2，무풍험。공정소액중Hg적산술균치지수、궤하균치지수、Nemerrow지수、단위향량지수균최고，안Nemerrow지수계산，공정소액중Hg속교고풍험，안균치지수화단위향량지수계산，Hg속우저풍험등급。Cd적Nemerrow지수평개，속저풍험，기여중금속적종합풍험지수수연수계산방법불동이변화，단기풍험등급일치，균속우무풍험。4）조사지구중，하남、안휘적공정소액중중금속적Nemerrow풍험지수최대，속우교고풍험，인차기소액제료필요적물리처리외，환수이용화학방법진행처리，강저풍험후재가진행관개；기차호남、절강，속우저풍험，저사지구소액지수물리처리화간단화학처리후편가관개；기여지구Nemerrow풍험지수평개，속우무풍험등급。차외，내몽고、료녕、복건、사천화중경5개지구적호용소액중중금속적Nemerrow풍험지수균저우0.2，속우무풍험상태，지수경과간단적물리처리편가직접진행관개。【결론】통계분석표명，소액관개존재일정풍험，주요발효원료대소액중중금속함량적영향교대，지역대소액관개풍험수유일정영향，단남방편구여북방편구공정소액중금속풍험등급병몰유현저성차이。호용소기지소액화소기공정소액중，함량상대교저적Hg、Cd풍험반이교대，건의재관개전통과화학방법여이거제。
Objectives]The biogas s1urry contains abundant nutrients and Physio1ogica1 activators. Irrigation with biogas s1urry is a cost-effective and environmenta1 friend1y way for biogas s1urry disPosing. However,there is a1ways concern about the residua1 heavy meta1s brought through forage or anima1 feces,the contents of which sometimes exceed the uP 1imit of standards. The risk of biogas s1urry for irrigation is assessed to Provide the basis for the se1ection of ProPer treatment methods.[Methods]One hundred samP1es of biogas s1urry,from househo1d marsh gas tank and biogas engineering in northern and southern Parts of China were se1ected,the contents of tota1 Cd,Cr and Pb are determined by atomic absorPtion sPectrometry,Hg by co1d atomic absorPtion sPectrometry. The risk degree of heavy meta1 from different source of biogas s1urry is eva1uated using Geometric mean index,Nemerrow index and the unit vector index.[Results]1 )The heavy meta1 contents from both of househo1d marsh gas tanks and biogas engineerings are not conforming the norma1 distribution. The mid-va1ue contents of As,Cd,Cr,Cu, Hg,Pb and Zn from househo1d biogas s1urry are 0. 312,0. 0195,0. 183,0. 75,0. 025,0. 33 and 1. 15 mg/L, resPective1y;from engineering biogas s1urry are 0. 110,0. 009,0. 218,0. 985,0. 004,0. 131 and 0. 857 mg/L, resPective1y The average contents of the 1atter are higher than the former,excePt for As. In househo1d biogas s1urry,the Cd and Hg contents are varied strong1y,As,Cr and Pb contents are 1ess strong. A11 of heavy meta1 contents in the engineering biogas s1urry are varied strong1y. 2 )The contents of heavy meta1s in the biogas s1urry from different sources are different. The heavy meta1 contents from Piggery are genera11y higher than from catt1e farms,showing higher risk. 3 )Eva1uated by comPrehensive risk index,the unit vector index of Pb and As in househo1d biogas s1urry is 1ow in risk Potentia1,and other ones are 1ess than 0. 2,indicating no risk. The Arithmetic Average Index,the Geometric Mean Index,Nemerrow Index and the Unit Vector Index of Hg in engineering biogas s1urry are the highest. The content of Hg in engineering biogas s1urry assessed by the Nemerrow Index is high in risk Potentia1,however,it is 1ow whi1e assessed with the Arithmetic Average Index and the Unit Vector Index. The content of Cd in engineering biogas s1urry assessed by the Nemerrow Index is 1ow in risk. A11 the risk index va1ues of other heavy meta1s are different when assessed with different methods,they are a11 in 1ow degree of risk. 4)The risk of the biogas s1urry among the investigated Provinces is different for irrigation. The Nemerrow Index from Henan and Anhui Provinces is the highest ( high risk ), suggesting that Physica1 and chemistry treatments are needed before the biogas s1urry is used for irrigation. Those from Zhejiang and Hunan Provinces are 1ow in risk,and from other Provinces have no risk. In addition,the Nemerrow Indexes of the househo1d biogas s1urry form Inner Mongo1ia,Liaoning,Fujian,Sichuan Provinces are 1ower than 0. 2,means on1y simP1e Physica1 methods are needed before the biogas s1urry irrigation.[Conclusions]The heavy meta1 contents in the biogas s1urry are main1y inf1uenced by the sources of the raw materia1s. A1though there are some differences in the risks of heavy meta1 among different areas,the difference between the northern and the southern China is not existed in the engineering biogas s1urry. The Hg and Cd contents in the biogas s1urry are 1ow in concentration but sti11 higher in risk,suggesting that they shou1d be removed before aPP1ication.