Siv tshuab tshiab, txuag zog ua silica tebchaw los ntawm cov ntaub ntawv tsis khws pes tsawg: mov hulls, thas thiab lis cawv.
Precipitated silica thiab lwm lub tebchaw silicon yog rau ntau yam khoom uas peb niaj hnub siv, thiab tsis yog rau cov me packets khij "TSIS TXHOB NOJ." Lawv nyob nraum siv los nqus ya raws uas yuav ua kom puas khoom tshiab, thiab feem ntau peb tsis txhob xav txog lawv.
Pua pua txhiab tus tons precipitated silica thiab lwm lub tebchaw silica no ua tau txhua txhua xyoo. Lawv nyob nraum siv los txhuam cov silicon wafers uas tso rau hauv electronics, los pab kom cov log tsheb, thiab ua xim tsev thiab daim ntawv dawb, raws li tus abrasive hauv tshuaj txhuam hniav, thiab muaj, countless ib packets ntawm silica gel hlaws dai.
Uas ua cov tebchaw-purity silicon hnub no ib qho kim heev thiab cov-muab txoj kev uas yuav tsum tau cua kub puas lawm silicon hlau thiab anthracite thee kom 3,500 degrees Celsius (6,332 degree Fahrenheit) nyob hauv ib lub cub tawg electric arc.
Cai Richard Laine, ib tug xibfwb kev kawm ntaub ntawv thiab engineering hauv Michigan lub tsev kawm ntawv uas tsim txoj kev tshiab, hais tias nws yuav cawm cov emissions ib tuj ntawm silica tebchaw uas ua li rau (6) tons. Nws estimates tus nqi uas tus txheej txheem yuav tsum muaj 90% tsawg tshaj li tus txheej txheem tam sim no, muaj zoo tsis muaj cov hneev.
Tus txheej txheem tshiab ntseeg tau tias yog thawj yooj yim, pheej yig tshuaj nug rau cov uas ua silica High School-purity tebchaw ntawm agricultural pov tseg.
Hulls nplej
Silica muaj ntau ntawm neeg ntiaj teb agricultural pov tseg, thiab tus nrhiav ib txoj kev uas ua tau rau nws extract stretches rov qab xyoo 80. Thaum txoj kev tshiab yuav siv mus tsim silica thiab cov silicon uas muaj tshuaj los ntawm ntau hom agricultural khib, Laine teem rau koj siv cov hulls uas tshuav ntawm ntxuav cov nplej.
Tus hull yog txheej qhov deb tshaj plaws ntawm cov nplej lis. Nws yuav tawm thaum mov tiav. 175,000 lab tus tons ntawm tus hulls yuav ua thoob qab ntuj txhua txhua xyoo. Ntau cov kub tuag los ua hluav taws xob, thiab cov hmoov tshauv uas tseem tshuav nyob muaj cov roj carbon silica. Tej co ntoo tshauv no yuav muab siv rau siv los ua rwb thaiv tsev, tab sis npaum nws yog dumped hauv landfills.
Tab sis thaum lub ntiaj teb no awash nyob hull silica-nplua nuj nplej ntoo tshauv, tau ntawd silica tau proven yog ib qho loj sib tw. Cov teeb meem stems feem ntau ntawm cov incredibly muaj zog tshuaj nyiaj ntawm silicon thiab pa, yog ib qhov haum siab uas tshwm sim tsuag.
Whyantifreeze thiab ethanol?
Laine pom ob yooj yim thiab pheej yig txoj kev siv rau cov nyiaj ntawd: ethylene glycol, los sis thas, thiab ethanol, los yog haus cawv lis. Lub chav nrog mentsis sodium hydroxide tsis muaj zog txog cov tshuaj bonds ntawm cov silica thiab cov txhuv hull tshauv pib ntawm qhov txheej txheem, dissolving tus silica hauv cov kua tov.
Ces cov tshuaj yuav ncu rhaub kom tus 390 degrees Celsius (734 degree Fahrenheit), txoj kev ua tus polymer silica thiab thas. Thaum no tsi tas zog, nws tus ntau tshaj offset yog lub zog uas ua thaum cov txhuv hulls yog kub tau pib ntawm txoj kev tuag. Thiab vim cov pa roj carbon tawm thaum lub hulls no kub tuag ntawd twb absorbed ntawm tsob zaub mov, cov txheej txheem qhov yog cov nruab nrab. Cov cua kub ua tus polymer silica-chav uas ces tau filtered kom tshem tau cov hmoov tshauv.
Lis cawv mam li teev kawg ntawm tus txheej txheem. Nws tseem zoo sib xws rau chav, kom nws yooj yim swaps nyob rau hauv los hloov cov chav, uas yog tus ces siv. Lub kua silica tau ces distilled tawm hauv qhov thib ob hais haum thiab muab ib yam khoom-purity precipitated silica muaj siv.
Laine tau ua lub tuam txhab, Mayasil, mus rau commercialize lub tshuab, yog in the process of ib tsob nroj "tos pilot" uas yuav muab tsim ib tug scaled tuaj manufacturing txheej txheem lub tsev. Yog cov teev tu zoo, Laine predicts tias nws yuav fundamentally hloov txoj kev silica khoom uas yuav tsim thiab siv.
"Kuv xav tias nws thiaj li, peb yuav tau yuav ua tau silica High School-purity thiab lwm tebchaw silicon ze tom teb nplej," Laine hais. "Nws yuav raug taus tus txheej txheem txhuv thiab zaub high-grade silica ib zaug xwb qhov chaw nrog me ntsis los yog tsis muaj cov hneev. Yog heev heev exciting."