Cov pawg tseem ceeb ntawm cov dej txo cov neeg ua haujlwm

Daim ntawv pom tau muab faib ua tus neeg sawv cev dej thiab hmoov. Cov ntsiab lus ntawm cov kua dej feem ntau yog 20%, 40% (tseem hu ua niam cawv), thiab 60%, thiab cov ntsiab lus ntawm cov hmoov feem ntau yog 98%.
Raws li cov dej-txo thiab txhim kho lub peev xwm ntawm cov dej-txo cov neeg ua haujlwm, lawv tau muab faib ua cov dej-txo cov neeg ua haujlwm zoo tib yam (tseem hu ua plasticizers, tus nqi txo dej tsis tsawg dua 8%, sawv cev los ntawm lignosulfonates [2]), High-efficiency dej-txo cov neeg ua haujlwm (tseem hu ua superplasticizer, tus nqi txo cov dej tsis tsawg dua 14%, suav nrog naphthalene series, melamine series, sulfamate series, aliphatic series, thiab lwm yam. [2]) thiab cov dej ua haujlwm siab (dej txo tus nqi tsis pub tsawg tshaj 25 %, sawv cev los ntawm polycarboxylic acid-raws li dej txo cov neeg ua haujlwm [2]), thiab muab faib ua hom muaj zog thaum ntxov, hom qauv thiab hom retardant.
Raws li cov ntaub ntawv muaj pes tsawg leeg, nws muab faib ua: (1) lignosulfonates; (2) polycyclic aromatic ntsev; (3) dej-soluble resin sulfonates.
Naphthalene series superplasticizer, aliphatic superplasticizer, amino superplasticizer, polycarboxylic acid superplasticizer, thiab lwm yam.
Raws li cov tshuaj muaj pes tsawg leeg, lawv feem ntau muab faib ua: lignosulfonate-raws li dej-txo cov neeg ua haujlwm, naphthalene-based high-efficiency dej-txo cov neeg ua haujlwm, melamine-based high-efficiency dej-txo cov neeg ua haujlwm, sulfamate-based high-efficiency dej- txo cov neeg ua haujlwm, thiab fatty acid-based high-efficiency dej-txo cov neeg ua haujlwm. Aqueous agents, polycarboxylate-based high-efficiency dej-txo cov neeg ua haujlwm.
Lignosulfonate
Lignosulfonate yog ib qho khoom los ntawm sulfite pulping. [4] Qhov hnyav molecular ntawm lignosulfonate yog 2000 ~ 5000, thiab pawg sulfonate yog 1.25 ~ 2.5mcq / g. Nws yog soluble hauv aqueous daws nrog ntau yam pH qhov tseem ceeb thiab insoluble hauv cov kuab tshuaj organic. Cov pab pawg ua haujlwm yog phenolic hydroxyl pawg. [5] Nws cov khoom siv raw yog lignin, uas feem ntau muab rho tawm los ntawm cov ntoo coniferous. Lignin yog polymerized los ntawm peb lignin monomers: p-peranyl cawv, coniferyl cawv, thiab sinapyl cawv, xws li: calcium lignosulfonate, Sodium lignosulfonate, magnesium lignosulfonate, thiab lignosulfonate dej-txo cov neeg ua haujlwm feem ntau siv cov dej txo qis. Lawv yog cov anionic surfactants thiab tuaj yeem siv ncaj qha lossis ua cov ntaub ntawv raw rau cov khoom sib xyaw. Ua ntej, vim nws pheej yig, nws tseem siv dav. Thaum siv hauv mortar, nws tuaj yeem txhim kho kev ua haujlwm, fluidity, lub zog, thiab dej txo tus nqi ntawm 8%-10%.
Txoj kev npaj: Feem ntau, muaj ob txoj hauv kev tseem ceeb rau kev rho tawm lignin los ua tus neeg sawv cev txo dej.
(1) Neutralize cov sulfite pov tseg kua nrog alkaline tov, tshem tawm cov suab thaj los ntawm lom fermentation, thiab evaporate thiab qhuav nws mus rau hauv hmoov-txo tus neeg sawv cev.
Piv txwv li, cov khoom ntawm Jilin Kaishantun Chemical Fiber Pulp Mill txais yuav txoj kev no. Nws siv cov kua khib nyiab los ntawm cov txheej txheem tsim cov tshuaj fiber ntau ua los ntawm cov nroj tsuag sulfite-siav ntoo (ntau dua 75% ntawm cov ntoo thuv dawb). Nws thawj zaug undergoes lom fermentation kom tshem tawm cov suab thaj thiab rho tawm cawv, thiab cov dej cawv seem uas muaj cov concentration ntawm 10% yog siv los ua raw khoom. Cov kua yog concentrated txog li 50% los ntawm ib tug evaporator, ces thauj mus rau ib tug sprayer kom qhuav, thiab ces tsuag-dryed nrog cua kub ntawm 200 degree. Nws pH =4 5-5.5. Cov khoom sib txawv thiab cov txheej txheem ua noj sib txawv muaj kev cuam tshuam ntau dua rau cov tshuaj muaj pes tsawg leeg ntawm sulfite pulp khib nyiab kua thiab cov txiaj ntsig lignosulfonate, yog li cuam tshuam rau kev ua haujlwm ntawm tus neeg saib xyuas dej.
(2) For alkali lignin or sulfate lignin, use acidification and precipitation to separate the lignin, and then perform sulfonation to generate lignin sulfonate in an alkaline medium. The lignin in the alkaline pulping black liquor exists in the form of alkali lignin. When the effective alkali content in the black liquor is >1.14%, alkali lignin yog yaj tag rau hauv cov cawv dub thiab dhau los ua hydrophilic gel yam tsis muaj nag lossis daus. Thaum cov ntsiab lus alkali zoo<0.71%, the alkali lignin colloid is partially destroyed. Precipitation occurs. Due to the presence of alkali lignin hydrophilic groups, the black liquor has a certain activity, but the effect is unstable. Therefore, to produce water-reducing agent from alkaline pulp waste liquid, it is necessary to introduce anionic surface active groups such as sulfonic acid group, amine group, and carboxyl group for modification. Lignin easily reacts with sulfonating agents such as sulfurous acid and sulfite to form lignosulfonate. The principle of the reaction is: the addition of sulfurous acid to the enol group in the molecule molecule introduces a sulfonic acid group. The reagent for introducing the sulfonic acid group is Na2S03. Since Na2S03 is hydrolyzed to generate H2SO3, the addition reaction can proceed in an alkaline medium. Produces lignosulfonate.
Daim ntawv thov txheej xwm: Cov tshuaj tua kab mob hauv tsev lignosulfonate feem ntau muaj peb txoj kev xaiv: 1) Siv ib leeg los ua tus neeg saib xyuas dej los npaj coagulation; 2) Siv nyob rau hauv ntau yam thaum ntxov-lub zog cov neeg ua hauj, thaum ntxov-lub zog dej-txo cov neeg ua hauj, retarder-txo cov neeg ua hauj lwm, thiab lwm yam. Kev npaj cov khoom ntawm composite admixtures xws li dej neeg sawv cev, retarding superplasticizer, twj tso kua mis, waterproofing agent; 3) Rau export. Raws li kev tshawb fawb, rau cov pob zeb hauv qab C30, 30% ntawm cov ntsiab lus ntawm sulfonate raug xa tawm.
Txawv teb chaws, lignosulfonate yog suav tias yog ib qho khoom noj khoom haus zoo. Kaus Lim Qab Teb tau xa 160,{1}} tons ntawm cov kua lignosulfonate los ntawm Tuam Tshoj txhua xyoo. Lub tebchaws United Kingdom, Tebchaws Meskas, Nyij Pooj, thiab lwm yam kuj tseem tuaj yeem nqa lignosulfonate los ntawm Tuam Tshoj. Nws yog tsuas yog siv los ua tus neeg saib xyuas dej-txo ib leeg lossis ua raw khoom rau cov khoom siv dej-txo cov khoom.