一 油品的閃點、燃點與自燃點概念解釋:
1.閃點
油品的閃點是預示出現火災和爆炸危險程度的指標,采用標準的開口閃點測定儀或閉口閃點測定儀laijinxingceding,shipingjiashiyouchanpinanquanxingdezhibiao。shandianshikeranxingyetidezhengqitongkongqidehunheqizailinjinhuoyanshi,fashengduanzanshanhuodezuidiwendu。shanhuoshiweixiaodebaozha,yiweizhezaiciwenduxiayoupinhuifachanshengdeyouzhengqiyizaikongqizhongdadaobaozhasuoxudenongdu。zhiyouhunheqizhongkeranxingqitidetijifenshudadaoyidingshuzhishi,yuhuocainengbaozha。nongduguoxiaohuoguodadoubuhuifashengbaozha,zhegenongdufanweichengweibaozhajiexian。zaibaozhajiexiannei,keranqizaihunheqizhongdezuiditijifenshuchengweibaozhaxiaxian;最zui高gao體ti積ji分fen數shu稱cheng為wei爆bao炸zha上shang限xian。油you品pin的de閃shan點dian就jiu是shi指zhi常chang壓ya下xia,油you品pin蒸zheng氣qi與yu空kong氣qi混hun合he達da到dao爆bao炸zha下xia限xian或huo爆bao炸zha上shang限xian的de油you溫wen。通tong常chang情qing況kuang下xia,高gao沸fei點dian油you品pin的de閃shan點dian為wei其qi爆bao炸zha下xia限xian時shi的de油you品pin溫wen度du。因yin為wei該gai溫wen度du下xia液ye體ti油you品pin已yi有you足zu夠gou的de飽bao和he蒸zheng氣qi壓ya,使shi其qi在zai空kong氣qi中zhong的de含han量liang恰qia好hao達da到dao油you品pin的de爆bao炸zha下xia限xian.因(yin)此(ci)一(yi)遇(yu)明(ming)火(huo)立(li)即(ji)發(fa)生(sheng)爆(bao)炸(zha)燃(ran)燒(shao)。由(you)於(yu)在(zai)試(shi)驗(yan)條(tiao)件(jian)下(xia)油(you)品(pin)用(yong)量(liang)很(hen)少(shao),著(zhe)火(huo)後(hou)瞬(shun)間(jian)可(ke)燃(ran)混(hun)合(he)氣(qi)即(ji)已(yi)燒(shao)盡(jin),所(suo)以(yi)人(ren)們(men)看(kan)到(dao)的(de)隻(zhi)是(shi)短(duan)暫(zan)的(de)火(huo)苗(miao)一(yi)閃(shan)。而(er)低(di)沸(fei)點(dian)油(you)品(pin),如(ru)汽(qi)油(you)及(ji)易(yi)揮(hui)發(fa)的(de)液(ye)態(tai)石(shi)油(you)產(chan)品(pin),在(zai)室(shi)溫(wen)下(xia)的(de)油(you)氣(qi)濃(nong)度(du)已(yi)經(jing)大(da)大(da)超(chao)過(guo)其(qi)爆(bao)炸(zha)下(xia)限(xian),其(qi)閃(shan)點(dian)實(shi)際(ji)上(shang)是(shi)它(ta)的(de)爆(bao)炸(zha)上(shang)限(xian)的(de)油(you)品(pin)溫(wen)度(du)。若(ruo)冷(leng)卻(que)以(yi)降(jiang)低(di)汽(qi)油(you)的(de)蒸(zheng)氣(qi)壓(ya),也(ye)可(ke)以(yi)測(ce)得(de)爆(bao)炸(zha)下(xia)限(xian)所(suo)對(dui)應(ying)的(de)閃(shan)火(huo)溫(wen)度(du)。由(you)於(yu)閃(shan)點(dian)是(shi)衡(heng)量(liang)油(you)品(pin)在(zai)貯(zhu)存(cun)、運輸和使用過程中安全程度的指標,所以測定低沸點油品爆炸下限的溫度沒有實際意義。
2.燃點
在測定油品開口杯閃點後繼續升高溫度,在規定條件下可燃混合氣能被外部火焰點燃,並連續燃燒不少子5s時的最低溫度,稱為燃點,通常稱為開口杯法燃點,是采用標準開口閃點和燃點測定儀進行測定,原則與測定開口閃點一致。閃點低子45℃液體的稱為易燃液體,閃點大於45℃的液體稱為可燃液體。
3.自燃點
jiangyoupinjiaredaohengaodewenduhou,zaishizhiyukongqijiechu,wuxuyinhuodianran,youpinjiyinjulieyanghuaerchanshenghuoyanzixingranshao,zhejiushiyoupindeziranxianxiang,nengfashengzirandezuidiyouwen,chengweizirandian。,yongbiaozhunde自燃點測定儀進行測定。
二 油品的閃點、燃點與自燃點與油品的組成關係:
1.與化學組成有關:通(tong)常(chang)情(qing)況(kuang)下(xia),烷(wan)烴(ting)比(bi)芳(fang)烴(ting)容(rong)易(yi)氧(yang)化(hua),故(gu)含(han)烷(wan)烴(ting)多(duo)的(de)油(you)品(pin)自(zi)燃(ran)點(dian)比(bi)較(jiao)低(di),但(dan)其(qi)閃(shan)點(dian)卻(que)比(bi)粘(zhan)度(du)相(xiang)同(tong)而(er)含(han)環(huan)烷(wan)烴(ting)和(he)芳(fang)烴(ting)較(jiao)多(duo)的(de)油(you)品(pin)高(gao)。在(zai)同(tong)類(lei)烴(ting)中(zhong),隨(sui)相(xiang)對(dui)分(fen)子(zi)質(zhi)量(liang)增(zeng)大(da),自(zi)燃(ran)點(dian)降(jiang)低(di),而(er)閃(shan)點(dian)和(he)燃(ran)點(dian)增(zeng)高(gao)。對(dui)碳(tan)原(yuan)子(zi)數(shu)相(xiang)同(tong)的(de)烴(ting)類(lei),自(zi)燃(ran)點(dian)的(de)順(shun)序(xu)為(wei):烷烴<環烷烴,烯烴<芳烴;嫩點的順序正好相反:烷烴>環烷烴,烯烴>芳烴。
2.與餾分組成有關:油品的閃點與其蒸氣壓有關,亦與其餾分組成有關,油品的沸點越高、餾分越重、相(xiang)對(dui)分(fen)子(zi)質(zhi)量(liang)越(yue)大(da),其(qi)閃(shan)點(dian)越(yue)高(gao)。反(fan)之(zhi),油(you)品(pin)的(de)沸(fei)點(dian)越(yue)低(di),餾(liu)分(fen)越(yue)輕(qing),相(xiang)對(dui)分(fen)子(zi)質(zhi)量(liang)越(yue)小(xiao),越(yue)易(yi)揮(hui)發(fa),其(qi)閃(shan)點(dian)和(he)燃(ran)點(dian)越(yue)低(di)。油(you)品(pin)閃(shan)點(dian)和(he)燃(ran)點(dian)的(de)高(gao)低(di)取(qu)決(jue)於(yu)低(di)沸(fei)點(dian)烴(ting)類(lei)含(han)量(liang),烷(wan)烴(ting)的(de)閃(shan)點(dian)比(bi)對(dui)應(ying)的(de)烯(xi)烴(ting)要(yao)高(gao)。油(you)品(pin)閃(shan)點(dian)的(de)高(gao)低(di)取(qu)決(jue)於(yu)油(you)品(pin)中(zhong)沸(fei)點(dian)最(zui)低(di)的(de)那(na)部(bu)分(fen)烴(ting)類(lei)的(de)含(han)量(liang)。當(dang)有(you)極(ji)少(shao)量(liang)輕(qing)油(you)混(hun)人(ren)到(dao)高(gao)沸(fei)點(dian)油(you)品(pin)中(zhong)時(shi),就(jiu)能(neng)引(yin)起(qi)閃(shan)點(dian)顯(xian)著(zhu)降(jiang)低(di)。例(li)如(ru),某(mou)潤(run)滑(hua)油(you)中(zhong)摻(chan)人(ren)1%的汽油,閃點可從200℃降至170℃。zhengshiyouyuzheyiyuanyin,yuanyoudeshandianshihendide,tahedishandianyoupinyiqibeilierenyiranwupinzhizhong。yurandianxiangfan,youpindefeidianyuedi,yuebuyiziran,qizirandianjiuyuegao;反之,自燃點越低。對同一烴類:沸點越高其燃點越高;沸點越高其自燃點反而較低。
1.閃點
油品的閃點是預示出現火災和爆炸危險程度的指標,采用標準的開口閃點測定儀或閉口閃點測定儀laijinxingceding,shipingjiashiyouchanpinanquanxingdezhibiao。shandianshikeranxingyetidezhengqitongkongqidehunheqizailinjinhuoyanshi,fashengduanzanshanhuodezuidiwendu。shanhuoshiweixiaodebaozha,yiweizhezaiciwenduxiayoupinhuifachanshengdeyouzhengqiyizaikongqizhongdadaobaozhasuoxudenongdu。zhiyouhunheqizhongkeranxingqitidetijifenshudadaoyidingshuzhishi,yuhuocainengbaozha。nongduguoxiaohuoguodadoubuhuifashengbaozha,zhegenongdufanweichengweibaozhajiexian。zaibaozhajiexiannei,keranqizaihunheqizhongdezuiditijifenshuchengweibaozhaxiaxian;最zui高gao體ti積ji分fen數shu稱cheng為wei爆bao炸zha上shang限xian。油you品pin的de閃shan點dian就jiu是shi指zhi常chang壓ya下xia,油you品pin蒸zheng氣qi與yu空kong氣qi混hun合he達da到dao爆bao炸zha下xia限xian或huo爆bao炸zha上shang限xian的de油you溫wen。通tong常chang情qing況kuang下xia,高gao沸fei點dian油you品pin的de閃shan點dian為wei其qi爆bao炸zha下xia限xian時shi的de油you品pin溫wen度du。因yin為wei該gai溫wen度du下xia液ye體ti油you品pin已yi有you足zu夠gou的de飽bao和he蒸zheng氣qi壓ya,使shi其qi在zai空kong氣qi中zhong的de含han量liang恰qia好hao達da到dao油you品pin的de爆bao炸zha下xia限xian.因(yin)此(ci)一(yi)遇(yu)明(ming)火(huo)立(li)即(ji)發(fa)生(sheng)爆(bao)炸(zha)燃(ran)燒(shao)。由(you)於(yu)在(zai)試(shi)驗(yan)條(tiao)件(jian)下(xia)油(you)品(pin)用(yong)量(liang)很(hen)少(shao),著(zhe)火(huo)後(hou)瞬(shun)間(jian)可(ke)燃(ran)混(hun)合(he)氣(qi)即(ji)已(yi)燒(shao)盡(jin),所(suo)以(yi)人(ren)們(men)看(kan)到(dao)的(de)隻(zhi)是(shi)短(duan)暫(zan)的(de)火(huo)苗(miao)一(yi)閃(shan)。而(er)低(di)沸(fei)點(dian)油(you)品(pin),如(ru)汽(qi)油(you)及(ji)易(yi)揮(hui)發(fa)的(de)液(ye)態(tai)石(shi)油(you)產(chan)品(pin),在(zai)室(shi)溫(wen)下(xia)的(de)油(you)氣(qi)濃(nong)度(du)已(yi)經(jing)大(da)大(da)超(chao)過(guo)其(qi)爆(bao)炸(zha)下(xia)限(xian),其(qi)閃(shan)點(dian)實(shi)際(ji)上(shang)是(shi)它(ta)的(de)爆(bao)炸(zha)上(shang)限(xian)的(de)油(you)品(pin)溫(wen)度(du)。若(ruo)冷(leng)卻(que)以(yi)降(jiang)低(di)汽(qi)油(you)的(de)蒸(zheng)氣(qi)壓(ya),也(ye)可(ke)以(yi)測(ce)得(de)爆(bao)炸(zha)下(xia)限(xian)所(suo)對(dui)應(ying)的(de)閃(shan)火(huo)溫(wen)度(du)。由(you)於(yu)閃(shan)點(dian)是(shi)衡(heng)量(liang)油(you)品(pin)在(zai)貯(zhu)存(cun)、運輸和使用過程中安全程度的指標,所以測定低沸點油品爆炸下限的溫度沒有實際意義。
2.燃點
在測定油品開口杯閃點後繼續升高溫度,在規定條件下可燃混合氣能被外部火焰點燃,並連續燃燒不少子5s時的最低溫度,稱為燃點,通常稱為開口杯法燃點,是采用標準開口閃點和燃點測定儀進行測定,原則與測定開口閃點一致。閃點低子45℃液體的稱為易燃液體,閃點大於45℃的液體稱為可燃液體。
3.自燃點
jiangyoupinjiaredaohengaodewenduhou,zaishizhiyukongqijiechu,wuxuyinhuodianran,youpinjiyinjulieyanghuaerchanshenghuoyanzixingranshao,zhejiushiyoupindeziranxianxiang,nengfashengzirandezuidiyouwen,chengweizirandian。,yongbiaozhunde自燃點測定儀進行測定。
二 油品的閃點、燃點與自燃點與油品的組成關係:
1.與化學組成有關:通(tong)常(chang)情(qing)況(kuang)下(xia),烷(wan)烴(ting)比(bi)芳(fang)烴(ting)容(rong)易(yi)氧(yang)化(hua),故(gu)含(han)烷(wan)烴(ting)多(duo)的(de)油(you)品(pin)自(zi)燃(ran)點(dian)比(bi)較(jiao)低(di),但(dan)其(qi)閃(shan)點(dian)卻(que)比(bi)粘(zhan)度(du)相(xiang)同(tong)而(er)含(han)環(huan)烷(wan)烴(ting)和(he)芳(fang)烴(ting)較(jiao)多(duo)的(de)油(you)品(pin)高(gao)。在(zai)同(tong)類(lei)烴(ting)中(zhong),隨(sui)相(xiang)對(dui)分(fen)子(zi)質(zhi)量(liang)增(zeng)大(da),自(zi)燃(ran)點(dian)降(jiang)低(di),而(er)閃(shan)點(dian)和(he)燃(ran)點(dian)增(zeng)高(gao)。對(dui)碳(tan)原(yuan)子(zi)數(shu)相(xiang)同(tong)的(de)烴(ting)類(lei),自(zi)燃(ran)點(dian)的(de)順(shun)序(xu)為(wei):烷烴<環烷烴,烯烴<芳烴;嫩點的順序正好相反:烷烴>環烷烴,烯烴>芳烴。
2.與餾分組成有關:油品的閃點與其蒸氣壓有關,亦與其餾分組成有關,油品的沸點越高、餾分越重、相(xiang)對(dui)分(fen)子(zi)質(zhi)量(liang)越(yue)大(da),其(qi)閃(shan)點(dian)越(yue)高(gao)。反(fan)之(zhi),油(you)品(pin)的(de)沸(fei)點(dian)越(yue)低(di),餾(liu)分(fen)越(yue)輕(qing),相(xiang)對(dui)分(fen)子(zi)質(zhi)量(liang)越(yue)小(xiao),越(yue)易(yi)揮(hui)發(fa),其(qi)閃(shan)點(dian)和(he)燃(ran)點(dian)越(yue)低(di)。油(you)品(pin)閃(shan)點(dian)和(he)燃(ran)點(dian)的(de)高(gao)低(di)取(qu)決(jue)於(yu)低(di)沸(fei)點(dian)烴(ting)類(lei)含(han)量(liang),烷(wan)烴(ting)的(de)閃(shan)點(dian)比(bi)對(dui)應(ying)的(de)烯(xi)烴(ting)要(yao)高(gao)。油(you)品(pin)閃(shan)點(dian)的(de)高(gao)低(di)取(qu)決(jue)於(yu)油(you)品(pin)中(zhong)沸(fei)點(dian)最(zui)低(di)的(de)那(na)部(bu)分(fen)烴(ting)類(lei)的(de)含(han)量(liang)。當(dang)有(you)極(ji)少(shao)量(liang)輕(qing)油(you)混(hun)人(ren)到(dao)高(gao)沸(fei)點(dian)油(you)品(pin)中(zhong)時(shi),就(jiu)能(neng)引(yin)起(qi)閃(shan)點(dian)顯(xian)著(zhu)降(jiang)低(di)。例(li)如(ru),某(mou)潤(run)滑(hua)油(you)中(zhong)摻(chan)人(ren)1%的汽油,閃點可從200℃降至170℃。zhengshiyouyuzheyiyuanyin,yuanyoudeshandianshihendide,tahedishandianyoupinyiqibeilierenyiranwupinzhizhong。yurandianxiangfan,youpindefeidianyuedi,yuebuyiziran,qizirandianjiuyuegao;反之,自燃點越低。對同一烴類:沸點越高其燃點越高;沸點越高其自燃點反而較低。
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