Ukuze uthole isimo somoya ezikhungweni zedatha, amasistimu aphakathi nendawo amaningi anemishini yokupholisa amanzi (ama-chiller) avame ukufakwa. Zisebenza kahle kakhulu kuneziphephetha-moya ze-freon, ngoba isipholile esizungeza phakathi kwamayunithi angaphandle nangaphakathi asingeni esimweni segesi, futhi iyunithi ye-compressor-condenser ye-chiller iqala ukusebenza kuphela lapho izinga lokushisa likhuphuka lifinyelela ezingeni elithile. Omunye wemibuzo ebaluleke kakhulu lapho uklama isistimu yokupholisa uwukuthi: yikuphi ukupholisa okungcono kakhulu ongakusebenzisa? Lokhu kungaba amanzi noma isisombululo samanzi se-polyhydric alcohols - i-propylene glycol noma i-ethylene glycol. Ake sizame ukuqonda izinzuzo nezingozi zenketho ngayinye.
I-Physics kanye ne-chemistry
Ngokombono wezakhiwo zomzimba (umthamo wokushisa, ukuminyana, i-kinematic viscosity), amanzi athathwa njengokupholisa okuphelele. Ngaphezu kwalokho, ingathululwa ngokuphepha emhlabathini noma ku-sewer. Ngeshwa, ezindaweni zethu, amanzi asetshenziswa endlini kuphela, njengoba eba yiqhwa ku-0 Β°C. Ngasikhathi sinye, ukuminyana kwe-coolant kuncipha, futhi umthamo owuthathayo uyanda. Inqubo ayilingani futhi akunakwenzeka ukuyinxephezela ngokusebenzisa ithangi lokunweba. Izindawo zokuqandisa zihlukanisiwe, ukucindezela okumile ezindongeni zamapayipi kwanda, futhi ekugcineni kwenzeka ukuphuka. Izisombululo ezinamanzi zotshwala obuyi-polyhydric azinayo le mibi. Ziba yiqhwa emazingeni okushisa aphansi kakhulu, ngaphandle kokwenza i-foci yendawo. Ukuminyana kwabo ngesikhathi se-crystallization kuncipha kakhulu kunangesikhathi sokuguqulwa kwamanzi abe yiqhwa, okusho ukuthi ivolumu ayikhuli kakhulu - ngisho nezixazululo ezinamanzi eziqandisiwe zama-glycols azibhubhisi amapayipi.
Ngokuvamile, amakhasimende akhetha i-propylene glycol ngoba ayinabo ubuthi. Eqinisweni, iyisengezo sokudla esivunyelwe i-E1520, esisetshenziswa ezimpahleni ezibhakiwe nokunye ukudla njenge-ejenti egcina umswakama. Isetshenziselwa izimonyo nezinye izinto eziningi. Uma uhlelo lugcwele isixazululo esinamanzi se-propylene glycol, akukho zinyathelo zokuphepha ezikhethekile ezidingekayo; ikhasimende lizodinga kuphela indawo yokugcina amanzi ukuze kunxephezele ukuvuza. Kunzima kakhulu ukusebenza nge-ethylene glycol - le nto ihlukaniswa njengobuthi obuphakathi (isigaba sesithathu sengozi). Ukugxila kwayo okuphezulu okuvunyelwe emoyeni kungu-5 mg/m3, kodwa ngenxa yokungaguquguquki kwayo okuphansi emazingeni okushisa avamile, umhwamuko walolu tshwala oluyi-polyhydric ungabangela ubuthi kuphela uma uphefumula isikhathi eside.
Isimo esibi kakhulu ngamanzi angcolile: amanzi kanye ne-propylene glycol akudingi ukulahlwa, kodwa ukugxila kwe-ethylene glycol ezindaweni zokusetshenziswa kwamanzi zomphakathi akufanele kudlule i-1 mg / l. Ngenxa yalokhu, abanikazi bezikhungo zedatha kuzodingeka bafake esilinganisweni samasistimu okudonsa amanzi akhethekile, iziqukathi ezivalekile kanye/noma uhlelo lokuhlambulula isipholisi esikhanyisiwe ngamanzi: awukwazi ukuvele usikhiphele phansi kumsele. Izithako zamanzi okuhlanjululwa zikhulu ngokuphindwe kayikhulu kunomthamo wesipholisi, futhi ukuwachithela phansi noma phansi akuthandeki kakhulu - utshwala obuyi-polyhydric obunobuthi kufanele bugezwe ngamanzi amaningi. Kodwa-ke, ukusetshenziswa kwe-ethylene glycol ezinhlelweni zesimanje zokupholisa umoya ezikhungweni zedatha nakho kuphephe kakhulu uma kuthathwa zonke izinyathelo zokuphepha.
Umnotho
Amanzi angabhekwa njengamahhala uma eqhathaniswa nezindleko zokupholisa okusekelwe kutshwala obuyi-polyhydric. Isixazululo esinamanzi se-propylene glycol sesistimu yekhoyili ye-chiller-fan siyabiza kakhulu - kubiza cishe ama-ruble angama-80 ilitha. Uma kucatshangelwa isidingo sokushintshwa kwesipholisi ngezikhathi ezithile, lokhu kuzoholela emananini amangalisayo. Intengo yesisombululo se-aqueous se-ethylene glycol cishe isigamu esiningi, kodwa kuzodingeka futhi ifakwe esilinganisweni sezindleko zokulahla, okuyinto, noma kunjalo, nayo incane kakhulu. Kunama-nuances ahlobene ne-viscosity namandla okushisa: i-coolant esekelwe ku-propylene glycol idinga ukucindezela okuphezulu okukhiqizwa yiphampu yokujikeleza. Ngokuvamile, izindleko zokusebenza kwesistimu nge-ethylene glycol ziphansi kakhulu, ngakho-ke le nketho ivame ukukhethwa, naphezu kobuthi obuthile bokupholisa. Enye indlela yokunciphisa izindleko ukusetshenziswa kwesistimu ye-double-circuit ene-heat exchanger, lapho amanzi ajwayelekile ejikeleza emakamelweni angaphakathi anezinga lokushisa elihle, futhi isisombululo se-glycol esingashisi sidlulisela ukushisa ngaphandle. Ukusebenza kahle kwesistimu enjalo kuphansi ngandlela thize, kodwa amanani okupholisa abizayo ancipha kakhulu.
Imiphumela
Eqinisweni, zonke izinketho ezisohlwini zezinhlelo zokupholisa (ngaphandle kwalezo zamanzi, okungenakwenzeka kuma-latitudes ethu) zinelungelo lokuba khona. Ukuzikhethela kuncike ezindlekweni eziphelele zobunikazi, okumele zibalwe esimweni ngasinye esivele sisesiteji sokuklama. Okuwukuphela kwento okungafanele uyenze ukushintsha umqondo lapho iphrojekthi isizolunga. Ngaphezu kwalokho, akunakwenzeka ukushintsha into epholile uma ukufakwa kwezinhlelo zobunjiniyela besikhungo sedatha esizayo sekuqhubeka. Ukujikijela nokuhlushwa kuzoholela ezindlekweni ezinkulu, ngakho-ke kufanele unqume ngokukhetha kanye unomphela.
Source: www.habr.com