Lub tshuab ua cov roj av demulsifiers yog lub hauv paus ntawm txoj cai hloov pauv theem-hloov pauv-rov qab-deformation. Thaum ntxiv cov demulsifier, kev hloov pauv theem tshwm sim: surfactants uas muaj peev xwm tsim cov emulsion hom sib txawv rau qhov uas tsim los ntawm emulsifier (hu ua rov qab-theem demulsifiers) los ua. Cov demulsifiers no cuam tshuam nrog hydrophobic emulsifiers los tsim cov complexes, yog li ntawd tshem tawm cov emulsifier ntawm nws lub peev xwm emulsifying.
Lwm txoj kev yog qhov kev sib tsoo ua rau daim zaj duab xis interfacial tawg. Nyob rau hauv cov xwm txheej ntawm cua sov lossis kev co, lub demulsifier muaj ntau lub sijhawm los sib tsoo nrog daim zaj duab xis interfacial ntawm cov emulsion, los yog adsorbing rau ntawm nws lossis displacement thiab hloov cov feem ntawm cov surfactants-active, yog li rupturing daim zaj duab xis. Qhov no txo qhov ruaj khov, ua rau flocculation thiab coalescence uas ua rau demulsification.
Cov roj av emulsion feem ntau tshwm sim hauv kev tsim khoom thiab kev ua kom cov khoom siv roj av. Feem ntau ntawm cov roj av nyoos hauv ntiaj teb tau txais hauv lub xeev emulsified. Ib qho emulsion muaj tsawg kawg yog ob lub kua uas tsis sib xyaw, ib qho yog dispersed zoo - droplets kwv yees li 1 μm hauv txoj kab uas hla - hauv lwm qhov.
Ib qho ntawm cov kua no feem ntau yog dej, lwm qhov feem ntau yog roj. Cov roj yuav tawg me me hauv dej uas cov emulsion dhau los ua roj-hauv-dej (O/W), qhov twg dej yog theem txuas ntxiv thiab roj yog theem tawg. Ntawm qhov tod tes, yog tias roj tsim theem txuas ntxiv thiab dej yog theem tawg, cov emulsion yog dej-hauv-roj (W/O) - feem ntau cov roj nyoos emulsion yog pawg kawg no.
Cov dej molecule nyiam ib leeg, ib yam li cov roj molecule; tsis tas li ntawd, ntawm cov dej thiab cov roj molecule muaj lub zog repulsive uas ua haujlwm ntawm lawv qhov interface. Kev nruj ntawm qhov chaw ua rau thaj chaw interfacial tsawg dua, yog li cov tee dej hauv W/O emulsion nyiam mus rau qhov sphericity. Ntxiv mus, cov tee dej ib leeg nyiam kev sib sau ua ke, uas tag nrho thaj chaw yog me dua qhov sib sau ua ke ntawm cov cheeb tsam tee dej sib cais. Yog li, cov emulsion ntawm dej ntshiab thiab roj ntshiab yog qhov tsis ruaj khov: cov theem dispersed gravitates mus rau coalescence, tsim ob txheej sib cais thaum interfacial repulsion raug counteracted - piv txwv li, los ntawm kev sib sau ua ke ntawm cov tshuaj tshwj xeeb ntawm qhov interface, uas txo qhov nro ntawm qhov chaw. Technologically, ntau daim ntawv thov siv cov nyhuv no los ntawm kev ntxiv cov emulsifiers paub zoo los tsim cov emulsions ruaj khov. Txhua yam tshuaj uas ruaj khov emulsion hauv txoj kev no yuav tsum muaj cov qauv tshuaj uas ua rau muaj kev sib cuam tshuam nrog ob qho tib si dej thiab roj molecules - uas yog, nws yuav tsum muaj ib pawg hydrophilic thiab ib pawg hydrophobic.
Cov roj emulsions uas yog crude oil emulsions muaj lawv qhov ruaj khov vim yog cov khoom ntuj tsim hauv cov roj, feem ntau muaj cov pawg polar xws li carboxyl lossis phenolic. Cov no yuav muaj nyob ua cov kua lossis colloidal dispersions, uas muaj feem cuam tshuam tshwj xeeb thaum txuas rau cov interfaces. Hauv cov xwm txheej zoo li no, feem ntau cov khoom me me tawg hauv cov roj theem thiab sib sau ua ke ntawm cov roj-dej interface, sib phim ua ke nrog lawv cov pawg polar uas taw rau dej. Yog li ntawd, ib txheej interfacial ruaj khov, zoo li ib lub plhaub khov kho zoo li ib txheej particulate lossis paraffin crystal lattice. Rau qhov muag liab qab, qhov no qhia tau tias yog ib txheej txheej uas qhwv cov txheej interface. Cov txheej txheem no piav qhia txog kev laus ntawm cov roj emulsions thiab qhov nyuaj ntawm kev tawg lawv.
Nyob rau xyoo tas los no, kev tshawb fawb txog cov txheej txheem demulsification ntawm cov roj av nyoos tau tsom mus rau kev tshawb nrhiav zoo ntawm cov txheej txheem coalescence ntawm cov dej thiab qhov cuam tshuam ntawm demulsifiers rau cov khoom rheological interfacial. Txawm li cas los xij vim tias qhov kev ua ntawm demulsifiers rau emulsions yog qhov nyuaj heev, thiab txawm tias muaj kev tshawb fawb ntau hauv daim teb no, tsis muaj kev tshawb fawb txog cov txheej txheem demulsification tau tshwm sim.
Muaj ntau txoj kev uas tau lees paub tam sim no:
③ Txoj kev yaj - Ib lub molecule lossis ob peb lub molecule ntawm lub demulsifier tuaj yeem tsim cov micelles; cov kauj macromolecular lossis micelles no yaj cov emulsifier molecules, ua rau cov roj emulsified tawg.
④ Txoj kev hloov pauv uas quav tau - Kev soj ntsuam me me qhia tau tias cov emulsions W/O muaj ob lossis ntau lub plhaub dej, nrog rau cov plhaub roj nyob nruab nrab ntawm lawv. Nyob rau hauv cov teebmeem ua ke ntawm kev ua kom sov, kev sib xyaw, thiab kev ua haujlwm demulsifier, cov txheej sab hauv ntawm cov tee dej sib txuas ua ke, ua rau cov tee dej sib koom ua ke thiab demulsification.
Tsis tas li ntawd xwb, kev tshawb fawb hauv tsev txog cov txheej txheem demulsification rau O / W emulsified roj av qhia tias lub demulsifier zoo tagnrho yuav tsum ua tau raws li cov qauv hauv qab no: kev ua haujlwm ntawm qhov chaw muaj zog; kev ua haujlwm zoo; lub zog flocculating txaus; thiab muaj peev xwm coalescing zoo.
Cov demulsifiers muaj ntau yam; faib ua pawg raws li hom surfactant, lawv suav nrog cationic, anionic, nonionic, thiab zwitterionic ntau yam.
Cov tshuaj anionic demulsifiers: carboxylates, sulfonates, polyoxyethylene fatty acid sulfate esters, thiab lwm yam - qhov tsis zoo suav nrog kev siv tshuaj ntau, kev ua haujlwm tsis zoo, thiab kev ua haujlwm tsis zoo hauv qhov muaj electrolytes.
Cov tshuaj cationic demulsifiers: feem ntau yog cov ntsev quaternary ammonium - zoo rau cov roj sib dua tab sis tsis haum rau cov roj hnyav lossis cov roj laus.
Cov tshuaj demulsifiers uas tsis yog ionic: cov tshuaj copolymers uas pib los ntawm cov amines; cov tshuaj copolymers uas pib los ntawm cov cawv; cov tshuaj alkylphenol-formaldehyde resin block copolymers; cov tshuaj phenol-amine-formaldehyde resin block copolymers; cov tshuaj demulsifiers uas ua los ntawm silicone; cov tshuaj demulsifiers uas hnyav heev; polyphosphates; cov tshuaj modified block copolymers; thiab cov tshuaj zwitterionic demulsifiers uas sawv cev los ntawm cov roj av imidazoline-based crude oil demulsifiers.
Lub sijhawm tshaj tawm: Lub Kaum Ob Hlis-04-2025