Common units ntawm gas detectors
1. Molar ntim ntawm cov pa roj: qhov ntim ntawm cov roj nyob hauv ib chav tsev ntawm cov khoom, lub cim yog Vm, thiab chav tsev feem ntau yog L / mol lossis m3 / mol. Nyob rau hauv cov xwm txheej txheem (0 degree , 101KP xeev), lub ntim nyob ntawm 1 mol ntawm ib qho roj av yog li 22.4L.
2. Vol feem pua : hais txog qhov concentration ntim piv ntawm cov roj sib xyaw.
3. feem pua LEL: Hais txog qhov feem pua ntawm cov khoom tawg qis ntawm cov pa hluav taws xob. LEL qhov tseem ceeb ntawm ntau yam roj hluav taws xob tuaj yeem tau txais hauv cov khoom siv.
4. ppm (parts permillion)/(1 × 10-6)/(μ): Qhia qhov chaw ib lab (qhov ib lab), los yog ib feem ntawm ib lab.
5. ppb: seem ib billion (ob peb), txheeb ze rau ug/L, ng/g.
6. ppt: seem ib trillion (ob peb), txheeb ze rau ng/L, pg/g.
7. Hloov cov roj ntsuas ntsuas
(1). Kev hloov pauv ntawm Vol% thiab feem pua LEL
Formula: feem pua LEL=(V÷LV) × 100 / Vol% =(L × LV) ÷100
V: paub ntim piv ntawm combustible gas concentration, Vol feem pua;
LV: qhov sib npaug ntawm qhov sib piv ntawm 100 feem pua LEL combustible gas, Vol feem pua;
L: Qhov feem pua ntawm cov kev txwv qis qis ntawm cov pa hluav taws xob, feem pua LEL.
(2). Převod LEL na LWD
Formula: ppm =(L × LV) × 100 / ％LEL=PM÷(LV × 100)
PM: paub roj, ppm;
L: qhov feem pua ntawm cov neeg tawg rog tsawg tsawg ntawm cov pa hluav taws xob, feem pua LEL;
LV: Qhov sib npaug ntawm qhov sib piv ntawm 100 feem pua LEL combustible gas, Vol feem pua.
(3). Kev hloov pauv ntawm mg / m3 rau ppm
Cov roj concentration ntsuas los ntawm cov cuab yeej ntsuas roj feem ntau yog qhov ntim concentration (ppm). Raws li cov kev cai ntawm peb lub teb chaws, tshwj xeeb tshaj yog lub tuam tsev tiv thaiv ib puag ncig, cov roj concentration yuav tsum tau qhia nyob rau hauv loj concentration units (xws li mg / m3), thiab peb lub teb chaws cov qauv thiab cov kev cai kuj qhia nyob rau hauv loj concentration units (xws li. mg/m3).
Siv qhov loj concentration unit (mg / m3) raws li txoj kev qhia ntawm cov concentration ntawm cov pa phem tuaj yeem yooj yim xam qhov tseeb ntawm cov pa phem. Txawm li cas los xij, qhov concentration ntawm huab hwm coj muaj feem xyuam rau qhov kub thiab txias ib puag ncig ntawm cov pa uas tau pom, thiab nws cov nqi yuav txawv nrog cov kev hloov hauv ib puag ncig xws li kub thiab cua siab; qhov tseeb ntsuas yuav tsum ntsuas qhov kub thiab txias atmospheric siab ntawm cov pa roj tib lub sij hawm. Txawm li cas los xij, thaum ppm yog siv los piav qhia txog qhov concentration ntawm cov pa phem, txij li qhov ntim piv tau siv, qhov teeb meem no yuav tsis tshwm sim.
Kev hloov pauv ntawm chav ntsuas ppm rau mg / m3 yog xam raws li cov qauv hauv qab no:
mg/m3=M/22.4*ppm*[273/(273 plus T)]*(Ba/101325)
Nyob rau hauv cov mis saum toj no: M - yog cov roj molecular hnyav, ppm - ntsuas qhov ntim concentration tus nqi, T - kub, Ba - siab, qhov no yog ib tug txheej txheem algorithm, tab sis nyob rau hauv peb qhov tseeb xam ua hauj lwm, kub thiab siab yuav ignored, rau Kev suav thiab nco Kev yooj yim tuaj yeem sau tseg raws li:
Thov xa mus rau lub rooj sib tham ntawm cov ntsiab lus rau kev suav ntawm qhov hnyav molecular ntawm M.
Piv txwv li, kev hloov pauv ntawm 100ppm H2S rau mg / m3 yog dab tsi?
M tus nqi ntawm H2S=1*2 ntxiv rau 16=18 yog 18/22.4*100=80 mg/m3. rov qab.
