Asphalt yog xim av-xim av sib xyaw ua ke ntawm hydrocarbons ntawm qhov sib txawv molecular hnyav thiab lawv cov derivatives uas tsis yog xim hlau. Nws yog ib hom high-viscosity organic kua. Nws yog kua, muaj xim dub, thiab soluble hauv carbon disulfide. Kev siv asphalt: Kev siv tseem ceeb yog cov khoom siv hauv tsev, cov khoom siv raw thiab roj. Nws daim ntawv thov thaj chaw muaj xws li kev thauj mus los (txoj kev, railways, aviation, thiab lwm yam), kev tsim kho, kev ua liaj ua teb, kev txuag dej, kev lag luam (kev lag luam, kev tsim khoom), kev siv pej xeem, thiab lwm yam.

Hom asphalt:
1. Coal tar pitch, thee tar pitch is a by-product of coking, uas yog, cov khoom dub uas tseem tshuav nyob rau hauv lub distillation kettle tom qab tar distillation. Nws tsuas yog txawv ntawm refined tar nyob rau hauv lub cev muaj zog, thiab tsis muaj ib tug meej ciam teb. Txoj kev faib tawm dav dav yog los qhia tias cov uas muaj qhov muag muag qis dua 26.7 ° C (tus qauv cubic) yog tar, thiab cov siab tshaj 26.7 ° C yog asphalt. Coal tar pitch mas muaj refractory anthracene, phenanthrene, pyrene, thiab lwm yam. Cov tshuaj no yog tshuaj lom, thiab vim muaj cov ntsiab lus sib txawv ntawm cov khoom, cov khoom ntawm coal tar pitch kuj txawv. Cov kev hloov hauv qhov kub thiab txias muaj qhov cuam tshuam zoo rau cov coal tar pitch. Nws yog nquag mus brittleness nyob rau hauv lub caij ntuj no thiab softening nyob rau hauv lub caij ntuj sov. Nws muaj ntxhiab tsw tshwj xeeb thaum cua sov; Tom qab 5 teev ntawm cua sov mus rau 260 ° C, anthracene, phenanthrene, pyrene thiab lwm yam khoom uas muaj nyob rau hauv nws yuav volatilize.

2. Petroleum asphalt. Petroleum asphalt yog qhov seem tom qab distillation ntawm cov roj crude. Nyob ntawm qhov degree ntawm refining, nws yuav ua kua, semi-kua los yog khoom nyob rau hauv chav tsev kub. Petroleum asphalt yog xim dub thiab ci thiab muaj qhov kub thiab txias. Txij li thaum nws tau raug distilled rau qhov kub siab tshaj 400 ° C thaum lub sij hawm tsim khoom, nws muaj tsawg heev volatile Cheebtsam, tab sis tej zaum tseem yuav muaj siab molecular hydrocarbons uas tsis tau volatilized, thiab cov tshuaj no muaj ntau los yog tsawg teeb meem rau tib neeg noj qab haus huv.

3. Ntuj asphalt. Ntuj asphalt yog khaws cia hauv av, thiab qee qhov tsim cov pob zeb hauv av los yog sib sau rau saum npoo ntawm lub ntiaj teb crust. Feem ntau ntawm cov asphalt no tau dhau los ntawm ntuj evaporation thiab oxidation, thiab feem ntau tsis muaj co toxins. Asphalt cov ntaub ntawv muab faib ua ob pawg: av asphalt thiab tar asphalt. Hauv av asphalt muab faib ua ntuj asphalt thiab roj av asphalt. Ntuj asphalt yog cov residue tom qab lub sij hawm ntev raug thiab evaporation ntawm cov roj seeping tawm hauv av; roj av asphalt yog cov khoom uas tau txais los ntawm kev kho cov roj seem uas tseem tshuav los ntawm cov roj av refined thiab ua tiav los ntawm cov txheej txheem tsim nyog. . Tar pitch yog cov khoom siv rov ua dua tshiab ntawm tar tau los ntawm carbonization ntawm cov thee, ntoo thiab lwm yam organic teeb meem.

Feem ntau ntawm asphalt siv nyob rau hauv engineering yog roj av asphalt, uas yog ib tug sib tov ntawm complex hydrocarbons thiab lawv cov non-metallic derivatives. Feem ntau lub teeb nyem ntawm asphalt yog nyob nruab nrab ntawm 240 ℃ ~ 330 ℃, thiab qhov hluav taws kub yog li ntawm 3 ℃ ~ 6 ℃ siab tshaj qhov chaw taws teeb, yog li kev tsim kho kub yuav tsum tau tswj hauv qab lub teeb nyem.