周談龍,尚 斌,董紅敏,朱志平,陶秀萍,張萬欽
(中國農(nóng)業(yè)科學院農(nóng)業(yè)環(huán)境與可持續(xù)發(fā)展研究所/農(nóng)業(yè)部設(shè)施農(nóng)業(yè)節(jié)能與廢棄物處理重點實驗室,北京 100081)
低碳氮比條件下豬糞堆肥氨氣和溫室氣體排放1*
周談龍,尚 斌,董紅敏**,朱志平,陶秀萍,張萬欽
(中國農(nóng)業(yè)科學院農(nóng)業(yè)環(huán)境與可持續(xù)發(fā)展研究所/農(nóng)業(yè)部設(shè)施農(nóng)業(yè)節(jié)能與廢棄物處理重點實驗室,北京 100081)
針對養(yǎng)殖場糞便產(chǎn)生量大、外加碳源物質(zhì)成本高,堆肥需要添加大量的碳源物質(zhì),并且豬糞堆肥實際生產(chǎn)過程中氨氣(NH3)和溫室氣體(GHG)排放數(shù)據(jù)缺乏的問題,開展了低碳氮比(C/N)條件下的豬糞堆肥試驗。試驗采用箱式堆肥法,使用Innova 1312對氨氣(NH3)、氧化亞氮(N2O)、甲烷(CH4)和二氧化碳(CO2)氣體進行24h在線連續(xù)監(jiān)測。結(jié)果表明:堆肥箱體內(nèi)日平均溫度超過50℃的持續(xù)天數(shù)均超過10d,滿足國家相關(guān)標準的無害化要求;經(jīng)過31d的好氧發(fā)酵,每千克初始原料鮮重的NH3、N2O、CH4和CO2的累計排放分別為2.27、0.07、0.24、135.72g,NH3的排放主要集中在堆肥第1周和翻堆后10d,分別占總排放的31.09%和36.15%,GHG排放主要集中在第4周,占總排放的30.9%;在不考慮CO2時,N2O是GHG的主要貢獻氣體,貢獻率為72.02%。堆肥過程中物料氣體(NH3、N2O、CH4和CO2)累計排放量均與pH值呈現(xiàn)良好的正相關(guān)(P<0.01)、與含水率和C/N呈現(xiàn)良好的負相關(guān)(P<0.01)。建議對豬糞堆肥過程中NH3的控制應(yīng)集中在堆肥第1周和翻堆后,GHG減排應(yīng)重點關(guān)注堆肥后期N2O的排放。
糞便;堆肥;氨氣;溫室氣體;碳氮比
堆肥作為畜禽糞便資源化利用的關(guān)鍵技術(shù)已經(jīng)得到廣泛應(yīng)用[1-3],但糞便堆肥過程中排放的 NH3、N2O、CH4等氣體,不僅會造成氮等營養(yǎng)元素的流失,還會產(chǎn)生二次污染,并直接影響堆肥技術(shù)的推廣與應(yīng)用[4]。
目前,國內(nèi)外針對畜禽糞便[5-9]、城市固體廢棄物[10-12]等堆肥過程中NH3和GHG排放開展了一定研究,且物料特性[13-14]、堆肥參數(shù)[15-17]及堆肥規(guī)模[18]對氨氣和溫室氣體排放都具有較大影響。但關(guān)于豬糞堆肥過程中NH3和GHG的排放研究大多集中在實驗室條件下,且以往研究推薦的最佳碳氮比(C/N)為25~30[19]。本研究以豬糞和秸稈為原料,通過減少秸稈等碳源添加物,達到低 C/N水平,在相同條件下處理更多的豬糞,以減少養(yǎng)殖場對秸稈等外加碳源物質(zhì)的經(jīng)濟投入,研究低 C/N條件下堆肥過程中NH3和GHG的排放規(guī)律,為豬糞堆肥中氣體減排提供數(shù)據(jù)支持。
堆肥試驗于2015年10月18日-11月21日在北京市大興區(qū)某豬場進行,原料包括豬糞和玉米秸稈,豬糞為豬場內(nèi)產(chǎn)生的鮮豬糞;玉米秸稈來自養(yǎng)殖場附近的村莊,秸稈經(jīng)過粉碎機切割成2~5cm長。玉米秸稈與豬糞混合體積比為 2∶1,混合物容重約為630kg·m-3,C/N為13.2,秸稈和豬糞具體特性如表1所示。
試驗采用密閉式強制通風好氧箱式發(fā)酵,共設(shè)置 3個堆肥箱,堆肥箱體有效體積為0.95m3,尺寸為 1m×1m×1m,主體結(jié)構(gòu)采用 1cm 厚聚氯乙烯(PVC)板,采用5cm聚乙烯作為保溫層(圖1),間歇式通風,每通風 10min停止 30min,通風率為60L·min-1·m-3[20-22],進氣通過篩板進入箱體并實現(xiàn)均勻布氣,發(fā)酵周期為31d,僅在第21天進行了翻堆,在試驗第18天出現(xiàn)連續(xù)26h停電,造成風機和檢測裝置Innova1312停止運行。
使用Innova1312實時監(jiān)測3個箱體排放的混合氣體中NH3、N2O、CH4和CO2的濃度。Innova1312使用前采用標準氣體 NH3、N2O、CH4、CO2(中國計量科學研究院提供)進行標定,每個采樣點每隔2min采1次樣,重復(fù)測定5次,取最后1次讀數(shù)進行計算,24h連續(xù)測定。
根據(jù)進氣口和出氣口濃度、通風量和堆體的初始質(zhì)量,計算單位初始物料的氣體排放通量,計算式為
式中,ERj表示單位質(zhì)量(濕重)初始物料排放第 j種氣體的排放速率(mg·kg-1·h-1),j=1、2、3、4,分別表示 NH3、N2O、CH4、CO2,Co,j和 Ci,j分別表示堆肥箱排氣口和進氣口處所測第 j種氣體的濃度(mg·m-3),Qair表示堆肥箱的通風率(m3·h-1),m 表示堆體原料的質(zhì)量(kg)。
表1 堆肥原料特性(平均值±標準差)Table 1 Characteristics of composting raw materials (mean±SD)
圖1 堆肥箱示意圖(mm)Fig. 1 Sketch diagram of composting bin(mm)
堆肥箱內(nèi)和環(huán)境溫度采用溫度自動采集器(HOBO Pro V2 U23-003)進行測定,溫度探頭放在堆肥箱體中軸處50cm左右的深度,記錄間隔為1h,日平均溫度為24h的平均值。
分別在堆肥第 1、5、9、12、15、20、22、26、31天時,從堆肥箱體上、中、下3層取等量樣品,均勻混合后送農(nóng)業(yè)部畜禽環(huán)境設(shè)施設(shè)備質(zhì)檢中心進行檢測,測定含水率、pH、總碳和總氮等指標。含水率采用烘箱干燥法測定;pH采用便攜式pH計法;總氮采用杜馬斯燃燒法。
式中,碳損失(μC,i)為不同形式碳損失相對于物料初始總碳質(zhì)量分數(shù)所占的比例,μC,i表示堆肥過程中第i種氣體排放的C損失率,i=1和2,分別表示CH4和CO2;mC,i表示每千克初始原料第i種氣體累計排放的C量(g·kg-1);MTC表示每千克初始原料中總 C 含量(g·kg-1)。
式中,氮損失(μN,i)為不同形式氮損失相對于物料初始總氮質(zhì)量分數(shù)所占的比例,μN,i表示堆肥過程中第i種氣體排放的N損失率,i=1和2,分別表示NH3和N2O;mN,i表示每千克初始原料第i種氣體累計排放的 N 含量(g·kg-1);MTN表示每千克初始原料中總N含量(g·kg-1)。
數(shù)據(jù)統(tǒng)計和分析利用SPSS statistics 20和Excel 2016,繪圖利用Sigma Plot 12.5軟件完成。
由圖2可見,試驗期間(2015年10月18日-11月 21日)堆肥箱外環(huán)境氣溫在 10℃上下,最高13.76℃,最低3.74℃。箱體內(nèi)日平均溫度從第1天開始就遠高于箱外,達30.93℃;隨后大幅升高,至第4天已超過50℃,并保持高溫較長時間;第21天翻堆時溫度略有下降,隨后繼續(xù)升高,最高時達到70℃。在整個堆肥31d過程中,溫度持續(xù)超過50℃的天數(shù)達 18d,符合糞便無害化衛(wèi)生要求(GB 7959-2012)中人工堆肥≥50℃至少持續(xù) 10d[23]和畜禽糞便無害化處理技術(shù)規(guī)范(NY/T1168-2006)中密閉式堆肥保持發(fā)酵溫度≥50℃不少于7d[24]的要求。
圖2 試驗期間箱外環(huán)境空氣溫度和堆體溫度逐日變化過程(平均值±均方差)Fig. 2 Variation of daily air temperature outside and daily temperature inside materials of composting bins(mean±SD)
由圖3a可見,試驗過程中堆體pH整體呈現(xiàn)增長的趨勢,從堆肥開始的7.1左右,經(jīng)過31d的好氧發(fā)酵達到8.0左右,滿足《有機肥料》(NY 525-2012)標準中 pH應(yīng)在 5.5~8.5的要求。堆肥物料 pH在6.7~9.0范圍內(nèi),堆肥過程中的微生物具有較高的活性[25],但相關(guān)研究表明,pH不是影響堆肥微生物活性的主要因素,幾乎所有物料的pH都在這個范圍內(nèi)[25]。堆體含水率變化如圖3b所示,水分是堆肥內(nèi)微生物生長繁殖的環(huán)境條件,又是物質(zhì)交換的媒介[26],在堆肥過程中具有重要的作用,在整個堆肥過程中呈現(xiàn)下降趨勢,但在未補充水分的條件下,試驗結(jié)束時堆肥物料的含水率仍在 52%左右,在微生物生長適宜的含水率(50%~60%)范圍內(nèi)。
圖3 堆肥pH值、含水率、TC和TN動態(tài)變化曲線Fig. 3 Change curves of pH value, water content, TC and TN during composting
TC在整個堆肥過程中呈現(xiàn)下降趨勢,試驗結(jié)束時堆肥物料的TC比初始值下降了10.9%,有機物的降解產(chǎn)生的揮發(fā)性含碳氣體是造成碳損失的主要原因。堆肥過程中雖然NH3和N2O等氣體的揮發(fā)造成氮含量的損失,但TN量出現(xiàn)了升高的趨勢,堆肥結(jié)束時,TN含量達3.1%,與尚斌等的研究[22,26-27]具有相似的結(jié)論,主要是由于干物質(zhì)下降的幅度超過TN下降的幅度,造成TN相對含量出現(xiàn)增加(如圖3c、d)。
NH3是好氧發(fā)酵過程中主要揮發(fā)性物質(zhì)之一,NH3排放不僅造成環(huán)境污染,還會造成氮流失。由圖 4可見,試驗期間NH3的日均排放量在16.8~164.1mg·kg-1(排放濃度在116.5~1137mg·m-3),排放主要集中在堆肥第1周和翻堆后。在堆肥第2天NH3排放迅速升高,隨后緩慢下降;在翻堆前,NH3濃度出現(xiàn)緩慢下降,是由于底部堆肥產(chǎn)生的NH3受到抑制,直到在翻堆作用下物料的重新分配[28]。NH3排放峰值出現(xiàn)在第21天翻堆后,達到 1137mg·m-3,遠遠超過《惡臭污染物排放標準》(GB 14554-93)[20]三級排放標準中 5.0mg·m-3的要求,高達其227倍。在整個堆肥過程中,每千克初始堆肥混合料的NH3排放為2265.48mg。
圖4 堆體NH3日排放量與累計排放量的變化Fig. 4 Change of NH3 daily emission and cumulative emission
堆肥過程中銨態(tài)氮的硝化與硝態(tài)氮的反硝化過程均有可能產(chǎn)生N2O,圖5為N2O日均排放量和累計排放量,由圖可見,堆肥前期N2O的排放相對較穩(wěn)定,后期出現(xiàn)較大的波動。N2O日均排放濃度范圍在 8.7~33.3.7mg·m-3,并且排放峰值出現(xiàn)在翻堆后,達 33.37mg·m-3,隨后迅速下降,翻堆后 N2O達到峰值可能是由于有氧條件下產(chǎn)生的硝酸鹽,進入?yún)捬鯀^(qū)域或微氧環(huán)境后,通過反硝化作用產(chǎn)生N2O,翻堆能夠顯著增加N2O的釋放,本試驗N2O排放在第18天時出現(xiàn)了短暫的上升,并保持2d較高的排放濃度,隨后恢復(fù)到之前水平,可能與堆肥第18天時出現(xiàn)的連續(xù)26h停電有關(guān),但其出現(xiàn)短暫上升的機理需要進一步深入研究。N2O的累計排放量如圖 5所示,在整個堆肥過程中,每千克初始堆肥混合料的N2O排放為66.83mg。
堆肥過程中CH4排放變化規(guī)律如圖6所示,由圖可見,堆肥初期 CH4排放濃度較高,中后期較低。CH4排放的高濃度出現(xiàn)在堆肥后的前 2d,隨后迅速下降,CH4濃度保持 40mg·m-3左右持續(xù)10d,但在堆肥的第 18天時,主要是由于出現(xiàn)超過26h的停電,氧氣供應(yīng)不足,造成CH4排放增加,濃度達到110mg·m-3。第21天翻堆后CH4濃度出現(xiàn)了小幅增長,主要是由于翻堆作用下,堆體內(nèi)的CH4得以釋放。堆肥后期幾乎不產(chǎn)生CH4,主要是由于有機物的大量減少,且隨著堆肥物料含水量的下降,厭氧區(qū)域減少。圖 6表明,在整個堆肥過程中,每千克初始堆肥混合料的 CH4累計排放量為237.36mg。
CO2排放主要集中在堆肥的開始階段和翻堆后,CO2的釋放速度表征了有機物的降解率和微生物活性[14],CO2排放規(guī)律與溫度具有相似的變化規(guī)律。在試驗過程中,CO2的排放濃度為15.58~46.83mg·m-3。CO2排放峰值在堆肥翻堆后,濃度高達 46.83g·m-3,隨后迅速下降,翻堆能夠顯著促進 CO2的排放,與Zhu等[28,30-31]具有相似的結(jié)論。CO2的累計排放量如圖7所示,在整個堆肥過程中,每千克初始堆肥混合料的CO2的累計排放量為135.72g。
圖5 N2O日排放量與累計排放量的變化Fig. 5 Change of N2O daily emission and cumulative emission
圖6 CH4日排放量與累計排放量的變化Fig. 6 Change of CH4 daily emission and cumulative emission
圖7 CO2日排放量與累計排放量的變化Fig. 7 Change of CO2 daily emission and cumulative emission
根據(jù)IPCC第五次評估報告[32],按100a尺度計算,CH4和N2O的全球增溫潛勢(GWP)分別是28和 256,將 CH4和 N2O轉(zhuǎn)化成二氧化碳當量(CO2-eq),計算出堆肥過程中溫室氣體排放如表 2和表3所示,考慮和不考慮CO2排放時的每千克初始原料的溫室氣體(CO2-eq)排放總量分別為159.48和 23.75g??紤] CO2時,CO2、CH4和 N2O累計排放分別占溫室氣體(CO2-eq)排放的85.10%、4.17%和10.73%。如果不考慮CO2,溫室氣體的排放以N2O為主,N2O和CH4的貢獻率分別為72.02%和27.98%。NH3的排放主要集中在第1周和翻堆后,分別占總排放的31.09%和36.15%,NH3揮發(fā)的氮素損失分別占初始TN的7.40%和8.61%;堆肥后期N2O排放占總排放的39.14%,以N2O形式揮發(fā)的氮素占初始總氮的0.21%;CH4排放各個階段差異性不大,第3周排放最高,占總排放的30.32%,占初始總碳的0.05%。可見,在本試驗中NH3-N是主要的氮損失來源,占初始TN的23.81%,CO2-C是主要的碳損失來源,占初始TC的35.83%。
氣體累計排放量變化規(guī)律與物料特性相關(guān)性分析如表4所示。由表可見,物料pH值與氣體累計排放呈現(xiàn)良好的正相關(guān)(P<0.01),相關(guān)系數(shù)都在 0.9以上;含水率與氣體累計排放量呈現(xiàn)良好的負相關(guān)(P<0.01),除了對 NH3的相關(guān)系數(shù)小于 0.9,其余均在0.9以上;C/N與氣體排放呈現(xiàn)良好的負相關(guān)(P<0.01),相關(guān)系數(shù)均在0.9以上。
表2 堆肥過程中碳氮損失和溫室效應(yīng)分析Table 2 Loss of carbon and nitrogen and total greenhouse gas emissions
表3 豬糞堆肥過程中GHG和NH3排放Table 3 GHG and NH3 emissions from manure composting bins
表4 堆肥過程中溫室氣體(GHG)累計排放量與pH、含水率和C/N的相關(guān)性分析Table 4 Correlation coefficient between the greenhouse gas emissions and pH value, water content and C/N ratio during composting period
本試驗以豬糞和秸稈為發(fā)酵原料,經(jīng)過 31d好氧發(fā)酵,堆肥發(fā)酵溫度超過50℃的持續(xù)天數(shù)均在10d以上,滿足現(xiàn)行相關(guān)標準的無害化衛(wèi)生要求;NH3排放濃度與溫度變化規(guī)律具有一定的相似性,NH3排放主要集中在堆肥高溫期(堆肥第1周和翻堆后),這與 Zhu等[28,32]研究具有相似的結(jié)論;N2O排放主要集中在堆肥后期,翻堆后N2O達到峰值可能是由于有氧條件下產(chǎn)生的硝酸鹽,進入?yún)捬鯀^(qū)域或微氧環(huán)境后,通過反硝化作用產(chǎn)生 N2O,翻堆能夠顯著增加N2O的釋放,與Ahn等[30,33]具有相似的結(jié)論。Ahn等[30]認為牛糞堆肥翻堆N2O排放是不翻堆處理的3.5倍,但是Zhu等[28]認為N2O排放在堆肥早期,翻堆不會對 N2O濃度造成影響,江滔等[17]也認為N2O排放與溫度變化趨勢相同,在堆肥的初期達到高峰,翻堆對N2O排放影響出現(xiàn)不同的研究結(jié)論,可能是由于試驗原料、運行控制條件和堆肥方式等對氣體的產(chǎn)生和排放的影響。本研究 CH4的排放主要集中在第3周,可能是由于第18天出現(xiàn)了超過26h的停電造成的,由于氧氣不足造成 CH4排放增加,但后期幾乎不產(chǎn)生CH4,主要是由于有機物的大量減少,且隨著堆肥物料含水量的下降,厭氧區(qū)域減少。CH4產(chǎn)生于厭氧條件下,在厭氧區(qū)域減至消失時,標志著堆肥的成熟[34]。
在整個堆肥過程中,每千克初始原料的 NH3、N2O、CO2和 CH4的累計排放分別為 2.27、0.07、135.72、0.24g,并且堆肥過程中氣體累計排放量與物料pH呈現(xiàn)良好的正相關(guān)(P<0.01),與含水率和C/N呈負相關(guān)(P<0.01)。其中NH3和N2O損失的氮占初始原料TN的23.81%和0.54%,CH4和CO2形式損失的碳占初始原料TC的0.17%和35.83%。整個堆肥過程中以NH3形式損失與Osada等[35]在豬糞堆肥過程中初始原料中 10%~25%的氮是以 NH3的排放而損失具有相似的結(jié)論;Beck-Friis等[36]認為,生活垃圾和麥稈堆肥過程中大于 98%的氮損失是以NH3的形式釋放,可以通過調(diào)節(jié) C/N,以減少 NH3的排放,或減少翻堆的頻率和添加覆蓋材料均可較好地實現(xiàn)減少 NH3的釋放[19];Boucher等[37]通過添加FeCl3降低污泥堆肥過程中NH3的排放。本研究以CH4形式損失的碳占原料總碳低于 Hao等[31]牛糞堆肥過程中的 CH4形式損失的 2%~3%,主要是由于原料的 C/N不同和堆肥工藝的差異性。相關(guān)研究表明,增加孔隙率和曝氣量可以減少 CH4的排放[13],對于CH4的控制應(yīng)集中在堆肥前期[16,38]。
綜上所述,在本研究工藝條件下,經(jīng)過 31d好氧發(fā)酵,滿足現(xiàn)行相關(guān)標準的無害化衛(wèi)生要求,在整個堆肥過程中,每千克初始原料的 NH3、考慮和不考慮 CO2的溫室氣體(CO2-eq)的累計排放分別為 2.27、159.48和 23.75g。建議對豬糞堆肥過程中NH3排放的控制集中在堆肥第 1周和翻堆后,GHG減排應(yīng)重點關(guān)注堆肥后期N2O的排放。
References
[1]Dong H M,Zhu Z P,Zhou Z K,et al.Greenhouse gas emissions from swine manure stored at different stack heights[J].Animal Feed Science and Technology,2011,166:557-561.
[2]Lim S L,Lee L H,Wu T Y.Sustainability of using composting and vermicomposting technologies for organic solid waste biotransformation:recent overview,greenhouse gases emissions and economic analysis[J].Journal of Cleaner Production,2016,111:262-278.
[3]Zhong J,Wei Y S,Wan H F,et al.Greenhouse gas emission from the total process of swine manure composting and land application of compost[J].Atmospheric Environment,2013,81:348-355.
[4]江滔,李國學,唐瓊,等.腐熟堆肥篩上粗顆粒對堆肥化過程中溫室氣體排放的影響[J].農(nóng)業(yè)環(huán)境科學學報,2015,34(7):1363-1370.Jiang T,Li G X,Tang Q,et al.Effect of adding coarse materials from matured compost on greenhouse gas emissions from organic wastes during composting[J].Journal of Agro-Environment Science,2015,34(7):1363-1370.(in Chinese)
[5]趙晨陽,李洪枚,魏源送,等.翻堆頻率對豬糞條垛堆肥過程溫室氣體和氨氣排放的影響[J].環(huán)境科學,2014,35(2):533-540.Zhao C Y,Li H M,Wei Y S,et al.Effects of turning frequency on emission of greenhouse gas and ammonia during swine manure windrow composting[J].Environmental Science,2014,35(2):533-540.(in Chinese)
[6]Hao X Y,Larney F J,Chang C,et al.The effect of phosphogypsum on greenhouse gas emissions during cattle manure composting[J].Journal of Environmental Quality,2005,34(3):774-781.
[7]Hao X,Chang C,Larney F J,et al.Greenhouse gas emissions during cattle feedlot manure composting[J].Journal of Environmental Quality,2001,30(2):376-386.
[8]謝軍飛,李玉娥.不同堆肥處理豬糞溫室氣體排放與影響因子初步研究[J].農(nóng)業(yè)環(huán)境科學學報,2003,22(1):56-59.Xie J F,Li Y E.Release of greenhouse gases from composting treatments on piggery excreta[J].Journal of Agro-Environment Science,2003,22(1):56-59.(in Chinese)
[9]Ge J Y,Huang G Q,Huang J,et al.Particle-Scale modeling of methane emission during pig manure/wheat straw aerobic composting[J].Environmental Science & Technology,2016,50(8):4374-4383.
[10]Ngnikam E,Tanawa E,Rousseaux P,et al.Evaluation of the potentialities to reduce greenhouse gases (GHG) emissions resulting from various treatments of municipal solid wastes(MSW) in moist tropical climates:application to Yaoundé[J].Waste Management & Research,2002,20(6): 501-513.
[11]Friedrich E,Trois C.GHG emission factors developed for the recycling and composting of municipal waste in South African municipalities[J].Waste Management,2013,33(11):2520-2531.
[12]楊帆,歐陽喜輝,李國學,等.膨松劑對廚余垃圾堆肥CH4、N2O和NH3排放的影響[J].農(nóng)業(yè)工程學報,2013,29(18): 226-233.Yang F,Ouyang X H,Li G X,et al.Effect of bulking agent on CH4,N2O and NH3emissions in kitchen waste composting [J].Transactions of the CSAE,2013,29(18):226-233.(in Chinese)
[13]Wang J Z,Hu Z Y,Xu X K,et al.Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure[J].Waste Management,2014,34(8):1546-1552.
[14]Awasthi M K,Wang Q,Huang H,et al.Influence of zeolite and lime as additives on greenhouse gas emissions and maturity evolution during sewage sludge composting[J].Bioresource Technology,2016,216:172-181.
[15]陳是吏,李國學,袁京,等.過磷酸鈣和雙氰胺聯(lián)用減少污泥堆肥溫室氣體及 NH3排放[J].農(nóng)業(yè)工程學報,2017,33(6):199-206.Chen S L,Li G X,Yuan J,et al.Combination of superphosphate and dicyandiamide decreasing greenhouse gas and NH3emissions during sludge composting[J]. Transactions of the CSAE,2017,33(6):199-206.(in Chinese)
[16]鐘佳,魏源送,趙振鳳,等.污泥堆肥及其土地利用全過程的溫室氣體與氨氣排放特征[J].環(huán)境科學,2013,34(11):4186-4194.Zhong J,Wei Y S,Zhao Z F,et al.Emission of greenhouse gas and ammonia from the full process of sewage sludge composting and land application of compost[J]. Environmental Science,2013,34(11):4186-4194. (in Chinese)
[17]江滔,Frank Schuchardt,李國學.冬季堆肥中翻堆和覆蓋對溫室氣體和氨氣排放的影響[J].農(nóng)業(yè)工程學報,2011,27(10):212-217.Jiang T,Frank S,Li G X.Effect of turning and covering on greenhouse gas and ammonia emissions during the winter composting[J].Transactions of the CSAE,2011,27(10):212-217.(in Chinese)
[18]Yasuyuki F,Takashi O,Dai H,et al.Patterns and quantities of NH3,N2O and CH4emissions during swine manure composting without forced aeration-effect of compost pile scale[J].Bioresource Technology,2003,89(2):109-114.
[19]Huang G F,Wong J W,Wu Q T,et al.Effect of C/N on composting of pig manure with sawdust[J].Waste Management,2004,24(8):805-813.
[20]郭東坡,陶秀萍,尚斌,等.死豬堆肥處理的通風率選擇探討[J].農(nóng)業(yè)工程學報,2013,29(5):187-193.Guo D P,Tao X P,Shang B,et al.Selection of ventilation rates on dead pig composting[J].Transactions of the CSAE,2013,29(5):187-193.(in Chinese)
[21]陶秀萍,郭東坡,董紅敏,等.冬季死豬與豬糞同步堆肥運行效果[J].農(nóng)業(yè)工程學報,2014,30(22):218-224.Tao X P,Guo D P,Dong H M,et al.Operation effects of dead pigs composted with swine manure in winter[J].Transactions of the CSAE,2014,30(22):218-224.(in Chinese)
[22]尚斌,陶秀萍,董紅敏,等.死豬堆肥處理通風率的優(yōu)化試驗[J].農(nóng)業(yè)環(huán)境科學學報,2014,33(10):2047-2052.Shang B,Tao X P,Dong H M,et al.Optimum ventilation rates for pig carcass composting[J].Journal of Agro-Environment Science,2014,33(10):2047-2052.(in Chinese)
[23]中華人民共和國衛(wèi)生部.GB7959-2012 糞便無害化衛(wèi)生要求[S].北京:中國標準出版社,2012.Ministry of Health of the PRC.GB7959-2012 Hygienic requirements for harmless disposal of night soil[S].Beijing:China Standards Press,2012.(in Chinese)
[24]中華人民共和國農(nóng)業(yè)部.NY/T1168-2006 畜禽糞便無害化處理技術(shù)規(guī)范[S].北京:中國標準出版社,2006.Ministry of Agriculture of the PRC.NY/T1168-2006 Technical requirement for non-hazardous treatment of animal manure[S].Beijing:China Standards Press,2006.(in Chinese)
[25]Bernal M P,Alburquerque J A,Moral R.Composting of animal manures and chemical criteria for compost maturity assessment:a review[J].Bioresource Technology,2009,100(22):5444-5453.
[26]徐衛(wèi)平.染疫動物生物安全靜態(tài)堆肥法的建立與評價[D].大連:大連理工大學,2010.Xu W P.Development and evaluation of bioresecure static composting systems for disposal of infeetious livestock mortalities[D].Dalian:Dalian University of Technology,2010.(in Chinese)
[27]高凌飛.墊料、菌渣聯(lián)合堆肥過程中碳氮轉(zhuǎn)化與溫室氣體排放研究[D].福州:福建農(nóng)林大學,2015.Gao L F.Study on transformation of carbon and nitrogen as well as greenhouse gas emission during pig breeding litter combine with mushroom residue composting [D].Fuzhou:Fujian Agriculture and Forestry University,2015.(in Chinese)
[28]Zhu Z P,Dong H M,Xi J L,et al.Ammonia and greenhouse gas emissions from co-composting of dead hens with manure as affected by forced aeration rate[J].Transactions of the ASABE,2014,57(1): 211-217.
[29]國家環(huán)境保護局,國家技術(shù)監(jiān)督局.GB 14554-93惡臭污染物排放標準[S].北京:中國標準出版社,1993.State Bureau of Environmental Protection,State Bureau of Technical Supervision.GB 14554-93 Emission standards for odor pollutants[S].Beijing:China Standards Press,1993.(in Chinese)
[30]Ahn H K,Mulbry W,White J W,et al.Pile mixing increases greenhouse gas emissions during composting of dairy manure[J].Bioresource Technology,2011,102(3):2904-2909.
[31]Hao X Y,Stanford K,Mc Allister T A,et al.Greenhouse gas emissions and final compost properties from co-composting bovine specified risk material and mortalities with manure[J].Nutrient Cycling in Agroecosystems,2009,83(3):289-299.
[32]IPCC.Climate change 2013:the physical science basis.Contribution of working group I to the fifth assessment report of the intergovernmental panel on climate change[R]. New York,NY,USA:Cambridge University Press,2013.
[33]Fukumoto Y,Osada T,Hanajima D,et al.Patterns and quantities of NH3,N2O and CH4emissions during swine manure composting without forced aeration-effect of compost pile scale[J].Bioresource Technology,2003,89(2): 109-114.
[34]Haga K.Animal waste problems and their solution from the technological point of view in Japan[J].Japan Agricultural Research Quarterly,1998,32(3):203-210.
[35]Osada T,Kuroda K,Yonaga M.Determination of nitrous oxide,methane,and ammonia emissions from a swine waste composting process[J].Journal of Material Cycles and Waste Management,2000,2(1):51-56.
[36]Beck-Friis B,Smars S,J?nsson H,et al.Gaseous emissions of carbon dioxide,ammonia and nitrous oxide from organic household waste in a compost reactor under different temperature regimes[J].Journal of Agricultural Engineering Research,2001,78(4):423-430.
[37]Boucher V D,Revel J C,Guiresse M,et al.Reducing ammonia losses by adding FeCl3during composting of sewage sludge[J].Water,Air,and Soil Pollution,1999,112(3-4):229- 239.
[38]Kuroda K,Osada T,Yonaga M,et al.Emissions of malodorous compounds and greenhouse gases from composting swine feces[J].Bioresource Technology,1996, 56(2): 265-271.
Emission Characteristics of Ammonia and Greenhouse Gas during the Low C/N Ratio Swine Manure Composting
ZHOU Tan-long, SHANG Bin, DONG Hong-min, ZHU Zhi-ping, TAO Xiu-ping, ZHANG Wan-qin
(Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences/Key Laboratory of Energy Conservation and Waste Management of Agricultural Structures, MOA, Beijing 100081, China)
The animal farms produce large amount of manure, and the composting process of animal manure needs to supply external carbon source material, which adds the treatment cost. In addition, the available data about the gas emission during low C/N composting of pig manure are lack. Hence, the emission of NH3(ammonia), N2O (nitrous oxide), CO2(carbon dioxide) and CH4(methane) during the composting of pig manure was monitored continuously using an Innova 1312 monitor. The results showed that the daily average temperature inside composing bin over 50℃ was more than 10 days, which could secure pathogen inactivation and meet the non-hazardous requirement of national standards. After 31d composting, cumulative emissions of NH3, N2O, CO2and CH4per kg initial matter were 2.27, 0.07, 135.72 and 0.24g, respectively. The NH3emissions occurred mainly in the first week and 10 days after turning, which account for 30.02% and 36.15% of the total NH3emission, respectively. Nevertheless, GHG(greenhouse gases) emissions focused on the fourth week, accounting for 30.9% of the total emissions. If CO2was not considered, N2O was the main contributor to GHG, with a contribution rate of 72.02%. There was a positive correlation (P<0.01) between the accumulated amount of gas emission (NH3, N2O, CH4and CO2) and the pH value during composting, and a good negative correlation with water content and C/N ratio (P<0.01). Therefore, the control of NH3during the composting of pig manure should be focused on the first week and after turning of the composting process, while GHG emission reduction should focus on the N2O emission during the later period of composting (the fifth week).
Manure; Composting; Ammonia; Greenhouse gas; C/N ratio
10.3969/j.issn.1000-6362.2017.11.001
周談龍,尚斌,董紅敏,等.低碳氮比條件下豬糞堆肥氨氣和溫室氣體排放[J].中國農(nóng)業(yè)氣象,2017,38(11):689-698
2017-02-17**
。E-mail:donghongmin@caas.cn
現(xiàn)代農(nóng)業(yè)產(chǎn)業(yè)技術(shù)體系建設(shè)專項資金(CARS-36-10B);公益性行業(yè)(農(nóng)業(yè))科研專項項目(201303091)
周談龍(1991-),碩士生,從事農(nóng)業(yè)廢棄物處理和資源化利用研究。E-mail:zhoutanlong@163.com