Txij thaum ub, tib neeg tau ntsib kev kub hnyiab. Thiab txij thaum ntawd los, ntoo tau siv los ua hom roj tseem ceeb, uas yog siv los ua kom sov ntau chav thiab ua zaub mov. Txawm hais tias muaj ntau yam khoom siv hluav taws xob, ntoo tseem yog cov roj siv hauv lub xyoo pua 21st vim nws cov nqi qis, muaj thiab yooj yim ntawm kev tuav. Rau nws txoj kev siv tau zoo thiab nyab xeeb hauv qhov cub thiab qhov cub, nws yuav tsum muaj qee cov ntaub ntawv hais txog nws lub cev thiab tshuaj lom neeg.
Yam cuam tshuam rau qhov kub thiab txias
Qhov siab tshaj plaws combustion ntawm ntoo nyob ntawm hom thiab tuaj yeem ncav cuag raws li hauv qab no:
- cov dej noo - tsis pub ntau tshaj 20%;
- qhov chaw kaw siv rau combustion;
- muaj pa oxygen hauv qhov xav tau.
Nws tseem tuaj yeem hlawv ntoo tshiab nrog cov dej noo ntawm 40 txog 60%, thaum:
- cov taws kub nyhiab tsuas yog hauv qhov cub zoo xwb;
- kub dissipationyuav txo los ntawm 20–40%;
- yuav muaj kev siv hluav taws ntau ntxiv, kwv yees li ob zaug;
- soot yuav nyob ntawm phab ntsa ntawm qhov cub thiab chimney.
Kev sib xyaw ua haujlwm yuav raug txo qis vim qhov xav tau ntawm qhov kub thiab txias, uas mus rau cov dej evaporation thiab hlawv cov tar los ntawm cov ntoo mos. Nyob rau hauv cov xwm txheej zoo, beech thiab tshauv muaj qhov kub thiab txias tshaj plaws, thiab poplar muaj qhov qis tshaj. Beech, larch, oak thiab hornbeam yog hom ntoo muaj txiaj ntsig thiab tsis siv los ua roj. Hauv cov xwm txheej hauv tsev, cov ntoo birch thiab coniferous yog siv los hlawv ntoo hauv qhov cub, txiav txim siab tias lawv muab qhov kub tshaj plaws thaum combustion.
Hnub twg kub kub?
Raws li twb tau hais lawm, ntoo yog ib qho ntawm cov roj siv ntau tshaj plaws rau cov tsev sov sab nraum lub nroog. Xav tias txhua qhov hluav taws kub kub ntawm qhov sib txawv, koj yuav tsum xaiv cov uas zoo dua. Qhov xwm txheej tseem ceeb rau kev hlawv ntoo yog qhov muaj cov pa oxygen, thiab qhov no feem ntau nyob ntawm qhov tsim ntawm lub qhov cub. Tsis tas li ntawd, txhua tsob ntoo muaj nws cov tshuaj muaj pes tsawg leeg thiab ntom. Qhov denser tsob ntoo, qhov kub hloov los ntawm nws. Qhov tseem ceeb tshwj xeeb rau kev hloov hluav taws xob ntau dua ntawm cov ntoo thaum combustion? Ntxiv nrog rau qhov ntom ntom thiab muaj cov pa oxygen, nws muaj cov dej noo ntawm cov ntoo.
Cov ntoo qhuav hlawv zoo dua thiab ua kom sov dua li cov ntoo ntub. Yog li ntawd, tom qab txiav lawv, lawv muab tso rau hauv woodpile thiab qhuav nyob rau hauv ib tug canopy rau ib xyoos. Txhua tus uas tau ua kom sov lub qhov cub nrog ntoo tau pom tias qee qhov ntawm lawv tau hlawv.ci, tso cua sov ntau, thaum lwm tus smolder thiab cua sov lub qhov cub me ntsis. Txhua yam, nws hloov tawm, nyob ntawm qhov hluav taws kub tawm ntawm hluav taws. Raws li qhov ntsuas no, cov hom tsim nyog tshaj plaws rau kev hlawv hauv qhov cub yog birch, ntoo thuv thiab aspen.
Yuav tso dab tsi thaum tsob ntoo hlawv?
Thaum ntoo raug hlawv, cov pa luam yeeb raug tsim tawm, muaj cov khoom siv (soot) thiab cov khoom siv hluav taws xob ntawm combustion. Lawv suav nrog cov khoom muaj nyob hauv ntoo. Cov khoom tso tawm thaum ntoo hlawv muaj nitrogen, carbon dioxide, dej vapor, sulfur dioxide thiab carbon monoxide, uas tuaj yeem hlawv ntxiv.
Nws kwv yees tias txhua phaus ntoo tawm kwv yees li 800 g ntawm cov khoom siv roj av thiab 200 g ntawm cov thee thaum combustion. Cov khoom muaj pes tsawg leeg ntawm cov khoom siv hluav taws xob kuj yog nyob ntawm cov xwm txheej hauv qhov txheej txheem no tshwm sim. Nws tuaj yeem yog:
- Incomplete - tshwm sim thaum muaj oxygen nkag tsis txaus. Raws li qhov tshwm sim ntawm combustion, cov tshuaj raug tso tawm uas muaj peev xwm hlawv dua. Cov no muaj xws li: soot, carbon monoxide thiab ntau yam hydrocarbons.
- Full - tshwm sim nrog kev nkag mus rau oxygen txaus. Raws li qhov tshwm sim ntawm combustion, cov khoom tsim - carbon dioxide thiab sulfur dioxide, dej vapor - uas tsis muaj peev xwm hlawv.
Kev piav qhia ntawm cov txheej txheem combustion
Muaj ntau theem ntawm kev hlawv ntoo:
- Cua sov - tshwm sim ntawm qhov kub ntawm qhov tsawg kawg 150 degrees Celsius thiab nyob rau ntawm qhov muaj hluav taws kub sab nraud.
- Ignition - qhov ntsuas kub yuav tsum yog ntawm 450 txog 620 degrees Celsius hauvNyob ntawm seb qhov dej noo thiab qhov ntom ntawm cov ntoo, nrog rau cov duab thiab qhov ntau ntawm cov ntoo.
- Combustion - muaj ob theem: fiery thiab smoldering. Rau qee lub sijhawm, ob hom kev ua haujlwm ib txhij. Tom qab tsim cov pa roj tso tseg, tsuas yog cov roj hlawv (smolders).
- Fading - tshwm sim thaum cov pa tawm los yog thaum cov roj ntws tawm.
Cov ntoo hnyav hlawv qeeb dua li cov ntoo tsawg dua vim nws cov thermal conductivity ntau dua. Thaum hlawv cov ntoo ntub, cov cua kub ntau yog siv rau ntawm cov evaporation ntawm cov dej noo, yog li lawv hlawv qeeb dua li cov ntoo qhuav. Kev hlawv ntoo puas yog lub cev lossis tshuaj lom neeg tshwm sim? Cov lus nug no yog qhov tseem ceeb ntawm cov tswv yim, thiab cov xwm txheej rau qhov siab tshaj plaws ntawm kev hloov mus rau qhov kub thiab txias lub sij hawm yuav nyob ntawm seb nws txhais tau li cas. Ntawm qhov tod tes, qhov no yog tshuaj lom neeg tshwm sim: thaum ntoo raug hlawv, cov tshuaj tiv thaiv tshwm sim thiab cov tshuaj tshiab raug tsim - oxides, cua sov thiab lub teeb raug tso tawm. Ntawm qhov tod tes, nws yog lub cev: thaum lub sij hawm tus txheej txheem, ib tug nce nyob rau hauv lub kinetic zog ntawm molecules tshwm sim. Yog li ntawd, nws hloov tawm hais tias cov txheej txheem ntawm hlawv ntoo yog ib tug complex lub cev thiab tshuaj phenomenon. Kev paub txog nws yuav pab koj xaiv hom ntoo zoo los muab koj tus kheej nrog lub sijhawm ntev thiab ruaj khov ntawm cov cua sov.
Ntawm cov pa taws uas tshwm sim thaum hluav taws kub
Thaum pov taws rau hauv qhov hluav taws kub, muaj pa taws thiab carbon monoxide ntau ntxiv - carbon monoxide. Ntxiv mus, cov pa taws tshwm nyob rau hauv ntau yam xim:
- Dawb yog aerosol, muaj cov tee dej me me thiab cov pa vapor, tawm losntoo txias. Cov pa luam yeeb muaj ib qho tsw ntxhiab tsw. Thaum lub cav cua sov, nws evaporates, tawg rau hauv nplaim taws thiab ploj mus.
- Grey - los ntawm liab-kub, tab sis tsis hlawv cav thiab hluav taws. Nws yog tsim los ntawm kub kub los ntawm boiling roj thiab resins thiab condenses mus rau hauv ib tug pos huab. Nws cov khoom me me dua li cov pa luam yeeb dawb, thiab nws sib dua thiab qhuav dua li nws.
- Black - burnt tar, hu ua soot. Nws yog tsim thaum lub sij hawm decomposition ntawm hydrocarbons nyob rau hauv ib tug nplaim hluav taws uas tsis txaus oxidation.
Haus luam yeeb los ntawm hluav taws nyob hauv lub cev mus ntev thiab muaj ntau yam tsis zoo. Qhov no yuav tsum nco ntsoov txhua tus uas nyiam zaum ntawm hluav taws.
khoom ntoo
Ntau hom ntoo muaj cov khoom hauv qab no:
- Xim - cuam tshuam los ntawm huab cua thiab hom ntoo.
- Shine - nyob ntawm seb lub plawv zoo li lub rays tsim.
- Texture - ntsig txog cov qauv ntoo.
- Moisture - qhov piv ntawm cov dej noo tawm mus rau qhov loj ntawm cov ntoo hauv lub xeev qhuav.
- Shrinkage thiab o - thawj yog tau los ntawm evaporation ntawm hygroscopic noo noo, o - nqus dej thiab nce ntim.
- Ntxig - txog tib yam rau txhua hom ntoo.
- Thermal conductivity - lub peev xwm ua kom sov los ntawm qhov tuab ntawm qhov chaw, nyob ntawm qhov ntom.
- Sound conductivity - tus cwj pwm los ntawm kev nrawm ntawm lub suab tawm, nyob ntawm qhov chaw ntawm cov fibers.
- Hluav taws xob conductivity - tiv thaiv kom dhauhluav taws xob tam sim no. Nws yog cuam tshuam los ntawm kev yug me nyuam, qhov kub thiab txias, av noo, kev taw qhia fiber ntau.
Ua ntej siv cov khoom siv ntoo rau qee lub hom phiaj, ua ntej ntawm tag nrho, lawv tau paub txog cov khoom ntawm ntoo, thiab tsuas yog tom qab ntawd nws nkag mus rau hauv kev tsim khoom.
Qhov zoo thiab qhov tsis zoo ntawm ntoo
Ntoo muaj qhov zoo hauv qab no:
- kev ua tau zoo heev;
- Nyob zoo ib tsoom phooj ywg;
- Zoo stained, polished, varnished;
- muaj peev xwm nqus suab;
- acid resistance;
- siab khoov muaj peev xwm.
Qhov tsis zoo ntawm cov ntoo muaj xws li:
- hloov pauv hauv cov duab thiab qhov loj me vim qhov shrinkage thiab o;
- tsis tawg tsis kam;
- rotting;
- kev puas tsuaj los ntawm kab;
- hluav taws thaum tsis ua raws li txoj cai kev nyab xeeb.
Kev siv ntoo hauv ntau yam kev lag luam
Ntoo yog siv dav hauv kev lag luam hauv qab no:
- Yplywood - veneer, plywood;
- ua haujlwm ntoo - ntoo boards, ntais ntawv, kws ntoo, rooj tog;
- logging - raw cov ntaub ntawv siv hauv kev lag luam ntoo tshuaj, khoom siv, khoom siv hluav taws xob txhua yam;
- sawmmill - ntau yam ntoo;
- tshuaj ntsuab - tar, charcoal, acetic acid;
- pulp thiab ntawv - ntawv, cardboard, pulp;
- hydrolysis - fodder poov xab, cawvethyl.
Zoo kawg
Ntoo yog ib qho khoom siv dav hauv ntiaj teb. Nws tau siv rau ntau pua xyoo hauv kev tsim kho, rooj tog tsim khoom thiab rau cov cua sov hauv tsev. Cov qauv ntoo yog siv hauv txhua tsev neeg. Ntoo yog nce siv nyob rau hauv ntau yam lag luam. Lub ntsiab zoo ntawm cov khoom no yog ib puag ncig tus phooj ywg, siab zog, ua haujlwm yooj yim, muaj peev xwm siv cov khib nyiab rau roj thiab lwm yam.
