Povećan hidraulički otpor u cevima jednoprotočnog parnog kotla usled zaprljanja: studija slučaja na parnom bloku snage 650 MWe na lignit

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Vladimir D. Stevanović Sanja Milivojević Milan M. Petrović Milica Ilić

Apstrakt

Sprovedena je analiza promene pritiska u toku vode i pare duž celokupnog cevnog sistema jednoprotočnog parnog kotla na bloku snage 650 MWe na lignit, nakon skoro 30 godina rada bez hemijskog čišćenja cevnog sistema. Utvrđen je značajan porast hidrauličkog otpora u poređenju sa projektnim vrednostima u isparivačkim cevima, kako u zoni zagrevanja, tako i u zoni isparavanja sa tokom dvofazne mešavine vode i pare. Uzrok ovog neželjenog efekta je formiranje talasne površine magnetitne naslage na unutrašnjoj površini zida cevi. Značajno povećana hidraulička hrapavost je određena na osnovu izmerenih promena pritiska u pojedinim sekcijama cevnog sistema i numeričkog proračuna sprovedenog termohidrauličkim modelom jednofaznog i dvofaznog strujanja u cevima. Model je zasnovan na bilansima mase, količine kretanja i energije fluidnih struja vode i pare u dvofaznom toku i mehanističkim korelacijama za transportne procese na razdelnim površinama faza. Razvijeni model je pogodan za određivanje parametara toka u opsegu od jednofaznog do dvofaznog strujanja u podkritičnim, nadkritičnim i uslovima bliskim kritičnom pritisku. Sprovedeni proračuni daju detaljan uvid u promene pritiska, brzine i temperature u cevnom sistemu kotla. Pad pritiska u isparivačkim cevima je skoro dvostruko veći u poređenju sa projektnim vrednostima nakon dugog perioda rada. Prikazani rezultati su podrška projektovanju kotla i pogonskih procedura i održavanju.

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Kako citirati
STEVANOVIĆ, Vladimir D. et al. Povećan hidraulički otpor u cevima jednoprotočnog parnog kotla usled zaprljanja: studija slučaja na parnom bloku snage 650 MWe na lignit. Zbornik Međunarodnog kongresa o procesnoj industriji – Procesing, [S.l.], v. 35, n. 1, p. 117-130, nov. 2022. Dostupno na: <https://izdanja.smeits.rs/index.php/ptk/article/view/6757>. Datum pristupa: 30 may 2024
Sekcija
Projektovanje, izgradnja, eksploatacija, i održavanje procesnih postrojenja

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