Cov chav nyob PPM, VOL thiab LEL li cas hauv cov khoom siv roj ntsha txhais tau li cas?
Hauv cov khoom siv roj av, cov khoom siv feem ntau yog VOL, PPM thiab LEL, yog li hnub no peb yuav kawm cov ntsiab lus thiab kev sib raug zoo ntawm peb chav nyob.
Ua ntej tshaj plaws, cia peb tham txog VOL, uas yog hais txog qhov ntim feem pua ntawm cov pa hauv huab cua, feem ntau yog qhia hauv%, xws li laser methane detector thiab oxygen detector; Piv txwv li, qhov ntsuas qhov ntsuas ntawm lub ntsuas pa oxygen yog 1 ~ 25% vol, uas txhais tau hais tias lub ntsuas pa oxygen no tuaj yeem siv los txheeb xyuas qhov chaw uas cov pa oxygen hauv huab cua nyob nruab nrab ntawm 0 ~ 25%.
ppm yog dab tsi? ppm yog hais txog qhov concentration txwv ntawm cov pa hauv huab cua, hu ua kev tso cai concentration. Raws li tau hais los saum no, qhov ntsuas qhov ntsuas ntawm hydrogen sulfide thiab sulfur hexafluoride feem ntau yog qhia hauv ppm. Vim hais tias cov pa paug ntawm cov pa roj carbon monoxide no yuav txawv ntawm qhov chaw sib txawv, cov tshuaj sulfur hexafluoride detector txhawb ntau qhov kev xaiv ntawm 0 ~ 100, 500, 1000, 2000 thiab 5000ppm.
LEL yog hais txog tus nqi siab ntawm lub tswb nrov, nrog rau feem pua ntawm chav ntsuas. Nws lub npe tag nrho yog Lower Disclosure Limited, uas yog hu ua LEL. Kev ntsuas ntau ntawm methane ntes yog 0 ~ 100% LEL. Qhov kev txwv qis ntawm methane tawg yog 5% thiab qhov txwv sab saud yog 15%, yog li thaum qhov concentration ntawm methane hauv huab cua nyob nruab nrab ntawm 5% thiab 15%, nws yuav tawg thaum nws ntsib qhov qhib nplaim taws, thiab thaum lub concentration ntawm methane. hauv huab cua qis dua 5% lossis siab dua 15%, nws yuav tsis tawg thaum nws ntsib cov nplaim taws.
Yooj yim muab tso, VOL stands rau ntim feem pua concentration, PPM stands rau concentration, thiab LEL stands rau qis tawg txwv. Qhov no puas yuav meej? Peb tau kawm, tsuas yog ua kom zoo dua rau peb cov neeg siv khoom.
ppm, VOL thiab LEL yog tag nrho cov units ntawm cov roj concentration. Puas muaj kev sib txuas ntawm lawv?
Ua ntej teb cov lus nug no, cia peb saib kev sib raug zoo ntawm ppm, VOL thiab LEL:
Vim hais tias lub ntsiab lus ntawm VOL% yog nyob rau hauv feem pua, thiab lub ntsiab lus ntawm PPM yog nyob rau hauv seem ib lab, yog li 10000 PPM=1 VOL. Yog li ntawd, kev sib raug zoo ntawm VOL thiab ppm yog: 1ppm=0.00001x100VOL, thiab 1VOL=10000ppm. Txawm li cas los xij, tsis muaj kev hloov pauv ncaj qha ntawm ppm thiab LEL, yog li LEL yuav tsum tau hloov mus rau VOL ua ntej, thiab tom qab ntawd hloov los ntawm vol thiab ppm.
