Ukusetshenziswa kwe-urea ku-diesel injini

Imithetho yesimanje yezemvelo ibeka imingcele eqinile emazingeni okukhishwa kwezinto ezingcolisa amagesi enjini kadizili. Lokhu kuphoqa onjiniyela ukuthi babheke izixazululo ezintsha ukuze bahlangabezane namazinga. Okunye kwalokhu bekuwukusetshenziswa kwe-urea kuphethiloli kadizili ohlelweni lwe-SCR (Selective Catalytic Reduction) exhaust aftertreatment system. Izinjini zakwaDaimler ezisebenzisa lobu buchwepheshe zibizwa ngeBluetec.

Luyini uhlelo lwe-SCR

I-Euro 6 protocol protocol ibilokhu isebenza emazweni angama-28 e-EU kusukela ngo-2015. Ngaphansi kwaleli zinga elisha, abakhiqizi bezimoto zikadizili bangaphansi kwezidingo eziqinile ngoba izinjini zikadizili zidala umonakalo omkhulu emvelweni nempilo yabantu ngokukhiphela umule nenitrogen oxide emkhathini.

Nakuba ukusetshenziswa kwe-converter ye-catalytic yezindlela ezintathu kwanele ukuhlanza amagesi e-exhaust enjini kaphethiloli, idivayisi eyinkimbinkimbi kakhulu yokuqeda amakhompiyutha anobuthi kumagesi aphumayo kuyadingeka enjini ye-diesel. Ukusebenza kahle kokuhlanza i-CO (i-carbon monoxide), i-CH (ama-hydrocarbons) nezinhlayiya ze-soot ezivela kumagesi e-diesel exhaust gas zikhuphuka emazingeni okushisa aphezulu, kuyilapho i-NOx, ngokuphambene nalokho, iyancipha. Isixazululo sale nkinga kwaba ukwethulwa kwe-SCR catalyst ohlelweni lwe-exhaust, esebenzisa i-diesel urea njengesisekelo sokubola kwezinhlanganisela ezinobuthi ze-nitrogen oxide (NOx).

Ukuze kuncishiswe ukungcola okuyingozi, onjiniyela basungule uhlelo olukhethekile lokuhlanza udizili - iBluetec. Inkimbinkimbi iqukethe amasistimu amathathu aphelele, ngalinye lawo lihlunga izinhlanganisela ezinobuthi futhi liphule izinhlanganisela zamakhemikhali eziyingozi:

• I-Catalyst - yenza i-CO ne-CH ingathathi hlangothi.
• Isihlungi se-particle - sicupha izinhlayiya ze-soot.
• I-SCR catalytic converter - Yehlisa ukukhishwa kwe-NOx nge-urea.

Uhlelo lokuqala lokuhlanza lwasetshenziswa emalolini nasezimotweni zakwaMercedes-Benz. Namuhla, abakhiqizi abaningi baguqulela izimoto zabo ohlelweni olusha lokuhlanza futhi basebenzisa i-urea ezinjinini zikadizili ukuze bahlangabezane nezidingo eziqinile zokulawula imvelo.

I-Technical urea AdBlue

Umkhiqizo wokugcina we-metabolism yezilwane ezincelisayo, i-urea, yaziwa kusukela ngekhulu le-XNUMX. I-Carbonic acid diomide ihlanganiswa nezinhlanganisela ezingaphili futhi isetshenziswa kakhulu kwezolimo. Embonini yezimoto, isixazululo se-Adblue technical fluid njenge-ejenti esebenzayo ekuhlanzweni kwamagesi anobuthi aphuma ku-nitrogen oxide.

I-Adblue ingu-40% we-urea kanye nama-60% amanzi acwecwe. Ukwakheka kufakwa ohlelweni lwe-SCR ku-nozzle lapho kudlula khona amagesi e-exhaust. Ukusabela kokubola kwenzeka, lapho i-nitric oxide ihlukana ibe ama-molecule e-nitrogen namanzi angenabungozi.

I-urea yobuchwepheshe yedizili - I-Adblue ayihlangene ne-urea urea, esetshenziswa emkhakheni wezimboni zezolimo kanye nasekhemisi.

I-Edblue injini ye-diesel

I-liquid exhaust aftertreatment system, noma isiguquli se-SCR, iyisistimu evaliwe lapho kugeleza okokukhipha udizili okungenasoot. Uketshezi lwe-Adblue luthelwa ethangini eliziqukathe ngokwalo bese lujova epayipini lokukhipha umoya ngesilinganiso esilinganisiwe ngaphambi kokungena kusiguquli.

Igesi exutshiwe ingena kuyunithi ye-SCR neutralization, lapho ukusabela kwamakhemikhali kwenzeka khona ukubola i-nitric oxide ngezindleko ze-ammonia ku-urea. Ngokuhambisana ne-nitric oxide, ama-athomu e-ammonia ayihlukanisa ibe izingxenye ezingenabungozi kubantu nasendaweni ezungezile.

Ngemuva komjikelezo ophelele wokuhlanza, inani elincane lokungcola likhishwa emkhathini, ipharamitha yokukhipha ihambisana nezivumelwano ze-Euro-5 ne-Euro-6.

Umgomo wokusebenza kwesistimu yokuhlanza i-diesel exhaust

Uhlelo oluphelele lokwelashwa kwenjini kadizili luqukethe isiguquli se-catalytic, isihlungi sezinhlayiya kanye nesistimu ye-SCR. Umgomo wokusebenza kokuhlanza ngezigaba:

1. Amagesi e-exhaust afaka isiguquli se-catalytic kanye nesihlungi sezinhlayiya. Umsizi uyahlungwa, izinhlayiya zikaphethiloli ziyashiswa, bese kukhishwa i-carbon monoxide nama-hydrocarbon.
2. Umjovo usetshenziselwa ukujova inani elithile le-AdBlue ekuxhumaneni phakathi kwesihlungi sezinhlayiya nesiguquli se-SCR catalytic. Ama-molecule e-Urea abola abe yi-ammonia ne-isocyanic acid.
3. I-ammonia ihlangana ne-nitrogen oxide, ingxenye eyingozi kakhulu yamafutha edizili asetshenzisiwe. Ama-molecule ahlukaniswa, okuholela ekwakhekeni kwamanzi ne-nitrogen. Amagesi akhipha umoya angenabungozi akhishelwa emkhathini.

Ukwakhiwa kwe-urea yedizili

Naphezu kokulula okubonakalayo koketshezi lwenjini ye-diesel, akunakwenzeka ukuzilungiselela i-urea ngokwakho usebenzisa umanyolo we-organic. Ifomula ye-molecule ye-urea (NH2) 2CO, ngokoqobo iyikristalu elimhlophe elingenaphunga, elincibilika emanzini nasezincibilikisini ezipholile (i-liquid ammonia, methanol, chloroform, njll.).

Emakethe yaseYurophu, uketshezi lukhiqizwa ngaphansi kokulawulwa yi-VDA (German Automobile Industry Association), ekhipha amalayisense ezinkampanini ezikhiqizayo, ezinye zazo ezihlinzeka ngoketshezi emakethe yasekhaya.

E-Russia, umgunyathi ngaphansi komkhiqizo we-AdBlue ungaphezu kwama-50%. Ngakho-ke, lapho uthenga i-urea yenjini ye-diesel eyenziwe eRussia, kufanele uqondiswe ngokumaka "Ukuhambisana ne-ISO 22241-2-2009".

Izinzuzo nezingozi nebubi

Izinzuzo zokusebenzisa i-urea zisobala - kuphela ngale reagent uhlelo lokwelapha igesi ephumayo yenjini yedizili ye-SCR ingasebenza ngokugcwele futhi ihlangabezane nezidingo ze-Euro 6 Standard.

Ngaphezu kokuvikela imvelo, izinzuzo zokuhlanzwa kwe-urea zifaka amaphuzu alandelayo:

• ukusetshenziswa kwayo ezimotweni kungu-100 g kuphela nge-1000 km ngayinye;
• uhlelo lwe-SCR luhlanganiswe ezimotweni zikadizili zesimanje;
• kwamanye amazwe intela yokusetshenziswa kwemoto iyancishiswa uma kufakwa uhlelo lokuhlanza i-urea, futhi ayikho ingozi yenhlawulo.

Ngeshwa, uhlelo luphinde lube nokubi:

• izinga lokubanda le-urea lingaba ngu-11 °C;
• isidingo sokugcwalisa amafutha njalo;
• izindleko zemoto ziyanda;
• inani elikhulu loketshezi lwe-Adblue mbumbulu;
• izidingo ezikhulayo zekhwalithi yamafutha;
• ukulungiswa okumba eqolo ezingxenyeni zesistimu.

Uhlelo oludidiyelwe lokukhuhla i-urea olwakhelwe ezimotweni zikadizili luhlala luwukuphela kwendlela yokunciphisa ukungcola okunobuthi. Ubunzima ekusebenzeni, izindleko eziphezulu zama-reagents amaloli, uketshezi olusezingeni eliphansi kanye nophethiloli wedizili kusho ukuthi abashayeli abaningi bakhetha ukuvala uhlelo nokufaka ama-emulators.

Kodwa-ke, kubalulekile ukuqonda ukuthi i-urea ihlala iwukuphela kwekhemikhali ye-diesel evimbela ukukhululwa kwe-nitric oxide endaweni ezungezile, okungaholela kumdlavuza.