Naphtha yog dab tsi thiab nws siv qhov twg?
Ligroin (tsawg dua hu ua naphtha) yog ib yam khoom uas muaj hluav taws kub thiab kub nyhiab ntawm distillation ntawm cov roj crude. Nws pom daim ntawv thov hauv ntau qhov kev lag luam - ob qho tib si ua kuab tshuaj thiab roj. Naphtha muaj nyob rau hauv peb hom - thee tar, shale, los yog roj. Txhua daim ntawv no yog tsim nyob rau hauv cov xwm txheej sib txawv thiab siv raws li nws cov khoom siv tshuaj.
Kev sib xyaw thiab cov yam ntxwv
Nyob ntawm lub sijhawm ntawm kev tsim cov tshuaj hydrocarbon, muaj pes tsawg leeg naphtha txawv. Piv txwv li, "laus" ligroin, uas yog raws li cov roj, muaj ib tug ntau dua flash point, yog tsawg volatile thiab muaj ib tug kuj siab ceev. "Young" ligroin txawv nyob rau hauv opposite zog, thiab nws lub hauv paus yog aromatic hydrocarbons.
Lub ntsiab lub cev ntawm cov khoom, yog li ntawd, yog txiav txim los ntawm lub sij hawm ntawm nws thawj tsim. Qhov tseem ceeb tshaj plaws yog:
- Kub kub: 90…140º C - rau roj av naphthas, thiab 60…80ºС - rau cov tshuaj tsw qab naphthas (tom kawg, los ntawm txoj kev, ua rau nws nyuaj rau kev txiav txim siab rau lawv, txij li cov txiaj ntsig zoo ib yam yog cov roj av ethers). Vim qis cov ntsiab lus kub naphthas feem ntau hu ua roj av ntsuj plig.
- Qhov ceev: 750-860 kg / m3.
- Kinematic viscosity: 1,05 ~ 1,2 hli2/ s.
- Qhov kub ntawm qhov pib ntawm gelation tsis siab dua: -60ºС.
Naphtha tsis yaj hauv dej thiab tsis sib tov nrog nws. Cov txheej txheem muaj pes tsawg leeg ntawm naphthas suav nrog hydrocarbons ntawm paraffinic thiab olefinic series, nrog rau naphthenic acids, thiab sulfur yog tam sim no nyob rau hauv ib qho me me ntawm inorganic ntsiab.
Nws siv nyob qhov twg?
Kev siv naphtha yog ib txwm siv rau cov laj thawj hauv qab no:
- Roj rau diesel xyaw.
- Solvent.
- Intermediate hauv kev lag luam petrochemical.
Naphtha yog siv los ua cov roj vim tias cov khoom yog flammable thiab yog tus cwj pwm los ntawm kev tso tawm ntau ntawm thermal zog thaum ignition. Tus nqi calorific ntawm naphtha nce mus txog 3,14 MJ / l. Vim lub fact tias naphtha burns yuav luag tsis muaj soot, cov khoom yog feem ntau siv nyob rau hauv domestic thiab neeg mus ncig tebchaws heaters, teeb pom kev zoo fixtures thiab lighters. Ncaj nraim li roj, naphtha tsis tshua siv, vim nws cov toxicity siab; ntau zaus muaj qhov qhia txog qhov ua tau ntawm nws txoj kev siv los ua ib qho ntxiv.
Kev lag luam rau kev tsim cov yas xws li polypropylene thiab polyethylene siv naphtha ua raw khoom. Nws cov derivatives kuj tau siv dav hauv kev tsim khoom ntawm butane thiab roj av. Naphtha hauv cov thev naus laus zis no tau koom nrog hauv cov txheej txheem ntawm chav tawg.
Naphtha ua cov kuab tshuaj tuaj yeem pom muaj nyob rau hauv ntau yam khoom siv tu, qhov twg nws cov ntsiab lus qis evaporation yog qhov tseem ceeb ua ib qho thinner rau cov xim, varnishes thiab asphalt. Cov tshuaj zoo tshaj plaws los ntawm cov koob no yog cov kuab tshuaj thiab naphthalene. Vim nws toxicity, naphtha feem ntau yog siv tsis yog rau lub hom phiaj hauv tsev, tab sis hauv kev lag luam (piv txwv li, cov khaub ncaws qhuav huv).
Naphtha toxicity
Kev nyab xeeb hauv kev siv dav ntawm cov khoom siv roj yog txwv los ntawm cov xwm txheej hauv qab no:
- High aggressiveness thaum raug rau ntawm daim tawv nqaij thiab cornea ntawm tib neeg lub qhov muag. Thaum sib cuag nrog naphtha, thaj tsam ntawm daim tawv nqaij swells mob. Nws raug nquahu kom ntxuav qhov chaw cuam tshuam nrog dej sov kom sai li sai tau.
- Kev xeev siab thiab kev puas tsuaj rau lub ntsws thaum nqos txawm tias me me ntawm cov tshuaj. Qhov no yuav tsum tau mus pw hauv tsev kho mob sai, txwv tsis pub ua pa tsis ua haujlwm, uas tuaj yeem ua rau tuag taus.
- Muaj zog tshwj xeeb tsw (tshwj xeeb tshaj yog rau "cov tub ntxhais hluas" aromatic naphthas). Kev nqus pa ntev ntev tuaj yeem ua rau ua pa thiab mob hlwb. Tseem muaj cov ntaub ntawv hais txog cov carcinogenicity ntawm cov tshuaj.
Txij li cov tshuaj muaj tshuaj lom, nws yog nruj me ntsis txwv tsis pub tso nws cov khoom seem rau hauv cov thawv uas tsis muaj kev tswj hwm (thiab, ntau dua li, rau hauv qhov qhib). Nws tseem yuav tsum tau nco ntsoov tias ligroin yog cov nplaim taws thiab tuaj yeem ua rau hluav taws.
