Teeb meem nyob rau hauv kev xaiv cov tshuaj lom thiab phom sij rau cov pa
Tseem muaj ntau yam teeb meem thaum xaiv ntau hom kev ntes, uas tau qhia tshwj xeeb hauv cov ntsiab lus hauv qab no:
(1) Kev tshawb nrhiav cov pa roj carbon monoxide tseem ceeb dua li kev tshawb nrhiav cov pa phem.
(2) Kev tshawb nrhiav cov pa roj uas tuaj yeem ua rau mob hnyav yog qhov tseem ceeb tshaj qhov kev tshawb nrhiav cov pa roj uas yuav ua rau muaj kev phom sij ntev.
Raws li cov lus qhia uas tau kawm los ntawm ntau qhov kev sib tsoo tawg tshwm sim los ntawm cov pa roj combustible, tib neeg tseem ceeb heev rau kev tshawb nrhiav roj combustible. Nws tuaj yeem hais tau tias nyob rau hauv ib qho chaw petrochemical lossis tshuaj lom neeg, feem ntau ntawm cov khoom siv phom sij yog LEL detectors. Txawm li cas los xij, tsuas yog siv cov cuab yeej LEL tseem nyob deb txaus los tiv thaiv kev nyab xeeb thiab kev noj qab haus huv ntawm cov neeg ua haujlwm tiag tiag.
Nws tsis tuaj yeem tsis lees paub tias feem ntau cov pa hluav taws xob tsis zoo yog cov roj hluav taws xob, tab sis catalytic combustion combustible gas detectors (LELs) tsis yog qhov kev xaiv zoo tshaj plaws rau kev kuaj xyuas tag nrho cov roj hluav taws xob. Nws yog tsim tshwj xeeb rau kev soj ntsuam methane, tab sis nws qhov kev tshawb nrhiav kev ua tau zoo rau lwm yam tshuaj tsis zoo. Yog li, qhov kev txwv qis qis ntawm cov roj hluav taws xob uas tsis yog methane uas lawv tuaj yeem ntes tau ntau dua li lawv qhov kev tso cai. Piv txwv li, rau cov pa phom sij thiab tshuaj lom xws li benzene thiab ammonia, tsuas yog siv lub ntsuas roj hluav taws xob yog ib txoj hauv kev txaus ntshai heev. Piv txwv li, qhov kev txwv qis qis ntawm benzene yog 1.2%, thiab nws qhov kho qhov tseem ceeb ntawm LEL ntes yog 2.51. Qhov no txhais tau hais tias qhov tso tawm concentration ntawm benzene ntawm lub LEL detector calibrated nrog methane tsuas yog 40% ntawm nws qhov tseeb concentration !! Nyob rau hauv no txoj kev, qhov tsawg kawg nkaus tswb concentration ntawm benzene uas yuav ntes tau los ntawm LEL yog 10% LEL=10% * 1.2% * 2.51=3.0 * 10-3, uas yog ze li ntawm 600 lub sij hawm siab tshaj qhov tso cai concentration ntawm benzene ntawm 5 * 10-6 !!. Ib yam li ntawd, lub tswb ceeb toom ntawm 1.5 * 10-2 rau ammonia tau txais ntawm LEL detector yog kwv yees li 600 lub sij hawm siab tshaj nws qhov tso cai concentration ntawm 2.5 * 10-5. Yog li ntawd, raws li cov roj sib txawv tau raug kuaj pom, xaiv ib qho tshuaj lom neeg kuaj pom muaj kev nyab xeeb dua thiab txhim khu kev ntseeg ntau dua li tsuas yog xaiv lub ntsuas LEL.
Tsis tas li ntawd, tam sim no peb muab qhov tseem ceeb heev rau kev tshawb nrhiav cov pa roj uas tuaj yeem ua rau mob hnyav, xws li hydrogen sulfide thiab hydrogen cyanide. Txawm li cas los xij, peb tsis them nyiaj txaus rau kev tshawb nrhiav cov pa roj uas tuaj yeem ua rau muaj kev phom sij ntev, xws li cov tshuaj tsw qab hydrocarbons thiab cawv. Qhov tseeb, qhov kawg ua rau muaj kev phom sij tsawg dua rau kev noj qab haus huv thiab kev nyab xeeb ntawm cov neeg ua haujlwm dua li cov pa roj uas tuaj yeem ua rau mob hnyav! Lawv tuaj yeem ua rau mob qog noj ntshav thiab lwm yam kab mob zais, cuam tshuam rau lub neej thiab kev noj qab haus huv ntawm cov neeg ua haujlwm. Qhov tshwm sim ntawm qhov tshwm sim no tsis yog vim kev txawj ntse xwb, tab sis kuj yog vim tsis muaj cov khoom siv hluav taws xob tsim hluav taws xob uas tuaj yeem kuaj xyuas qhov qis dua hauv kev ua lag luam yav dhau los.
