NGHIEN CU'U-TRAO DOI \i TiM HI^U VAN OE LOT GIO TRONG BO SAY KHONG KHi H | NHIET KIEU QUAY TRONG NHA MAY NHIET DIEN T THAN CONG S U A T 300 - 600 WIW LEARN ABOUT AIR LEAKAGE IN ROTARY AIR PREHEATER FOR THE THERMAL POWER PLANT 300 - 600MW PGS,TS Nguyin Chi Sang, ThS Phan Hfiu Thing, ThS Dao Hflu Manh Viln Nghien cflu Co khi, Bd Cdng Thfldng Bdi bdo gidi thieu tdm tdt cdng dung, tinh ndng, nguyen ly hogt ddng cd bdn ciia bd say khdng hoi nhiet kieu quay, mdt cum thiit bi quan trgng nhd mdy nhiit diin chay than cd cdngsudt tU 300 din 600 MW Khd ndng lot gio bg say ndy cd y nghia Idn khdng chi din hiiu sudt cua bd say, md cdn dnh hUdng quan din hieu suat chung ciia cd nhd mdy Ndi dung tinh todn khd ndng lot gid vd cdc kit cdu thiit kitoi Uu, vgt lieu cdng dUdc nghien cUu bdi bdo ndy Cdc kit qud nghien cdu da dUdc dp dung tot thtfc tetgi Nhd mdy Nhiet dien Than Hdi Phdng Tfl khda: Tinh todn, thiit ki; Bd say khdng hoi nhiet kieu quay; Lgt gid ABSTRACT This article summary presents the use, features, basic operating principle of rotary - thermal recovery air heater - important equipment unit in coal-thermal power plants with a capacity of 300 to 600 MW The ability tofall the wind in this heater have great significance not only for the heater's performance, but also an important influence on the performance of the whole plant Calculated content of ability for the failed wind and the optimal structural design, material are also studied in this article The research results have been applied well in actual at Hai Phong coal-thermal power plant Keywords: Calculation, design; Rotary - thermal recovery air heater; Failed wind ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, Sd nam 2016 www.cokhivietnam.vn NGHIEN CU'U-TRAO l D A T VAN DE Bd siy khdng (BSKK) li thilt bi gia nhiet dUdc sfl dung d cudi dfldng khdi thoit he thong Id hdi cua nha may nhiet diln ddt than, cd cic chdc ning chinh: - Tan dung nhilt cua khdi thoit d l gia nhiet cho khdng cap v i o Id vfla giam nhilt cua khdi thoit trinh ton that, vda cii thiln hieu suit cua Id hPi v i tilt kiem nhien lieu dung Id hPi Theo tinh toan, n l u nhilt dp khdi thoit giim dflpc IS^C, thi hieu suit cua Id hdi cd the ting 1% [1]; - Cai thiln q u i trinh chiy va tang nhiet dp budng dot cua Id hPi, vi cap gid ndng vao se tao q u i trinh bit chiy nhiln lieu tot hdn, dong thdi lira giam ton that nhiet hiln tfldng chay khdng h o i n toin cua nhien lieu tfl dd l i m tang hilu suit nhilt cua Id hoi; BSKK hdi nhiet, trflde tien khdi lam ndng kim loai rdi sau dd nhilt tich tu tai day v i dflpc truyin cho khdng Nhfl viy, mdi phan tfl cua bd siy khdng se lim viec d t r ^ g thii tiep xuc lin Iflpt thi vdi khdi, thi vdi khdng Bd siy khdng hdi nhilt kilu quay dfldc md t i tren hinh 1, cd cau tao bdi rotor, dd cd chfla cic khdi phan td trao doi nhiet quay lien tuc q u i trinh trao ddi nhilt Khdi ndng tfl phia tren di vio bd siy khdng di qua cic t i m phin tfl trao doi nhiet xuong phia dfldi ngoii theo dfldng khdi Khdng (gid) di tfl dudi di len thdng qua dfldng gio dau vao di vio bd siy khdng Idii v i di qua cic ting t i m phin tfl tich nhiet cua rotor, gid lanh niy se hap thu nhilt tfl cic tam tich nhiet da cd nhilt dp cao khdi l i m ndng lln trflde do, sau dd se di qua dudng gid dau - Tilt kilm dflpc tieu hao vit lieu va giam gii thinh sin xuit; - Sfl dung gid ndng de siy than se thuan lpi va de dang hdn cho he thong nghiln than Theo nguyin tic truyin nhiet, bd siy khdng Idii dflpc chia lim loai: Loai thu nhilt v i loai hdi nhiet Bp siy khdng kilu thu nhiet li loai dfldc sfl dung rpng rai nhflng nam trflde diy, ve cau tao nd gdm cic kilu nhfl: Kilu bing t i m thep, kieu bang dng gang, kieu bang dng thep Uu dilm chu yeu cua BSKK kilu thu nhilt li cd kit ciu ddn giin de chi tao, nhflng nhupc dilm dilm chinh li kich thfldc v i khdi Iflpng kim loai chi tao rat Idn Chinh vi khic phuc dflpc cic nhupc dilm neu tren, m i BSKK hoi nhilt Idlu quay hien dang dflpc flng dung tflpng doi biln cac n h i miy nhiet dien dot than cd cdng suit Idn Hinh Cdu tgo BSKK hoi nhiet kieu quay Trong pham vi khudn Idio cua bai bao niy, se t^p trung nghiln cflu cac vin de Ipt gid v i khdi xiy BSKK hdi nhiet kieu quay Do d Viet Nam hien nay, chUa cd cic tii lieu tinh toin thilt k l BSKK hdi nhiet kieu quay mpt cich hoan chinh, kl ca cic tii lieu thilt k l chi tilt cic BSKK dang lap dat tai cic nha miy nhiet dien nfldc Tfl cic kit qua khao sit"^ ISSN 0866 - 7056 TAP CHi CO KHi VIET NAM, S6 nam 2016 www.cokhivietnam.vn NGHIEN CU'U-TRAODOI Iiy mau kit hpp vdi vile tham k h i o sfl dung cac tai lieu tinh toan cua cic tic gii di trUdc, nhdm d l tai da dfla mot nhflng dang thiet k l phu hpp d l chi tao cac sin pham khio nghiem nhfl cic khoi phan td trao doi nhilt, t i m chen kin cac loai dfla vao flng dung lap dat BSKK cua Nha may Nhiet diln Hai Phdng HIEN TUONG LOT G l VA ANH H U N G CUA LOT GlO TRONG BSKK HOI NHIET KIEU QUAY 2.1 Cac loai lot gid Mdt nhdng nhfldc diem chu ylu cua bd siy khdng kieu hdi nhiet kilu quay la Iflpng khdng (gid) lot vao dfldng khdi kha Idn, vi theo nguyin ly hoat dpng cua BSKK kilu quay, ddng gid di qua BSKK ludn cd i p suit dflpng, cdn ddng khdi di qua BSKK ludn cd ap suit am Hien tflpng Ipt gid sang khdi se lam anh hfldng den hieu suit cua BSKK ndi rilng va cua c i Id hPi ndi chung Bp say khdng ma dl tai Ifla chpn lam ddi tfldng nghiln cflu thilt k l la loai cd ba ngin bao gom: -01 ngan dudng khdi, 01 ngin dfldng gid cip va ngan dfldng gid cip 2; - La loai BSKK cd 03 ting trao doi nhiet bao gom: Ting dau ndng, tang trung gian va tang lanh; ' Gifla cac ngan: Khdi - Gid cip 1; Gid cip 1- Gid cip 2; Gid cip 2- Khdi li cac vung qua dd (vung khdng cd khdi, gid di qua) Khi bd siy Ididng Idii boat ddng, se cd hien tUpng lot gid xiy Tren hinh la so cac kilu lot gid nhu sau: - Lpt gid trflc tiep: Cic vi tri cd t h i xiy lot gid trflc tiep nhfl sau: + Tai vi tri Idie hd gifla rotor va vd rotor; + Tai vi tri cac vung q u i dp: Do cd chenh i p gifla ddng gid cd i p suit dflPng v i ddng khoi cd ap suit i m n i n cd lpt gid tfl dfldng gid sang dfldng khdi tai cac vdng niy; - Lpt gid cuon theo: La Iflpng gid lpt keo theo rotor nd di qua tfl phia gid den phia khdi va di qua tfl phia khdi din phia gid Lflpng gid lpt theo niy phu thudc vao dfldng kinh v i tdc dp rotor 2.2 Anh hfldng cua lot gid den bo say khdng Khi xuat hien hien tflpng Ipt gid bd say khdng cua Id hoi, thi inh hfldng nhat cda van de lpt gid se l i m giim hieu suit ddt chiy nhiln lilu cua Id hPi, dan den lim giim cdng suit phat diln chung cua n h i may Ngoii ra, giy anh hfldng den cic thilt bi khac nhU: Tang diln ning tieu thu cua quat gid v i ting sfl an mdn cda dfldng khdi Sfl lot khdi v i lpt gid cua bd say khdng he thdng Id hPi cd the tic ddng ding k l den tinh nang nhiet cua thilt hi trao ddi nhiet Sfl lpt khdi xiy d ci diu ndng va diu dau lanh cua bd siy khdng Hau hit sfl lot gid xiy d dau lanh lam cho sfl an mdn cic be mat lim kin dan den khe hd tang len Ngoai ra, mdt vin d^ quan trpng khac la sfl lpt gid cua bd siy khong cd the lim giam nhilt dp khdi vao, ddng thdi cung tang lflu Iflpng gid cua quat gid cap cho BSKK ISSN 0866 - 7056 TAP CHi CO KHI VIET NAM, S6 nam 2016 www.cokhivietnam.vn NGHIEN c i i u - TRAO OOl i(%) = ( l - j ^ ) x l 0 (1) Trong do: L (%) - Ty 11 phin tram gii tri lot gid; - Tdng lflu Iflpng khdi vao BSKK, t/h; V/, - Tong lflu Ifldng khdi BSKK, t/h Htnh Sd lgt gio, khoi BSKK Bi giim thilu tdn thit ning Iflpng xay lot gid d vi tri giao gida ddng gid khdi thi nhat thilt phai thiet k l va lap dit mdt he thdng tam chen cd k h i ning kilm soit v i giim thieu sfl lot gid khdi cda BSKK Ylu ciu thilt kl he thdng tam chen cin dflpc xem xet din sfl dan nd tang nhiet dp cua ket cau rotor cua BSKK, vfla d i m b i o mflc dp hieu qua chen kin dong thdi he thdng chen cd pham vi dieu chinh dp lpt gid rdng v i thuan lpi q u i trinh b i o dudng, sda chda Nhfl viy, mdt van d l quan trpng thiet k l BSKK l i lim the nao b i o d i m dflpc that kin khdng cd lot gid tai cac vi tri cd the xay Day cung la mdt nhflng nhiem vu nghiln cflu thiet ke cac BSKK hdi nhiet kieu quay TINH T O A N TY LE LOT GIO VA Hl£U S U A T L A M VIEC CUA T H I ^ B I [5], [6], 17], [8] 3.1 Xic dinh ti 11 lot gid cua bo say khdng hoi nhilt kilu quay, L(%) Mdc dd lpt gid - Khdi cd the dfldc xic dinh bang nhieu each khic nhau, dd, cich phd bien nhit li xic dinh theo ty ll phan tram cua lUu lupng ddng khdi vao v i thiet bi va dfldc xic dinh theo cdng thfle (1) dfldi d i y Mpt each khac cung hay dflpc sfl dung la xic dinh ty 11 lpt gid bang phflong phip ndng dp dxy tai diu vao v i diu phia ddng khdi cua BSKK dflpc xic dinh theo cdng thfle (2) dfldi diy L(%): 0.89*(O,,-O,J ;clO0% 21-0^, (2) Trong do: O^^ li % Ifldng d xy dupc d phia diu ra; Oj^ la % lupng d xy dflpc d phia diu vio 3.2 Danh g i i hilu suit lam viec cua thilt hi De dinh gii hieu suat lam vile cfla thiet bi, can dUa tren viec xic dinh mpt sd cic chi tilu sau diy 3.2.1 Hieu sudt phia dong khoi cda BSKK Hieu suit phia ddng khdi la mdt chi sd dung de danh gia tinh trang van hinh cua bd say khong khi, dUpc xac dinh theo cdng thdc (3) Khi Idia nang say ndng khdng (gid) giam se lam giim hieu suit cua bp say Dieu ddng nghia vdi viec nhiet dp cua ddng khdi khdi bd siy se tang cao va nhilt dp khdng (gid) cap vio Id giim di Khi do: (3)^ ATI ISSN 0866-7056 TAP CHJ CO KHl VIET NAM, S6 nam 2016 www.cokhivietnam.vn NGHIEN CU'U-TRAO D | 3.2.2 Hieu sudt phia dong gio cda bo sdy khong khi, dddc xac dinh theo cong thUc (7) Trong do; GSE - Hilu suit phia dUdng khdi cua BSKK, %; AT^ - Chenh lech nhiet dp cua khdi, gid phia dau vao BSKK, "C; 7^, - Ton thit nhilt dp cua khdi vao, BSKK dflpc xic dinh theo cdng thfle (4) (4) T„ = ?i -T Trong do: T^ - Nhiet khdi diu vio cua BSKK, "C; Tg^ - Nhilt dp khdi dau cua BSKK, °C, khdng tinh den sfl lpt gid dflpc xic dinh theo cdng thfle (5) dfldi diy: T - J^-K 100 (5) +r; Trong do: 7; - Nhilt dp khdi diu BSKK, "C; - Nhiet dp gid diu vio BSKK, "C T'-f ASE = -^.—f*100 (7) Trong do: ASE - Hieu suit phia dfldng gid cua BSKK, %; 7; - Nhiet dp gid dau BSKK, °C; 3.3 Ty 11 ve hieu suit cua BSKK (X) Gia tri ty 11 X - Phu thudc vio dp am co than, mflc dp lpt gid, ty 11 lflu Iflpng gio va khdi, dflpc xac dinh theo cdng thdc (8) Ty 11X khdng xac dinh hilu suit cda bd siy khdng khi, nhflng nd cho biet dflpc tmh trang vin hinh cua bd siy khdng Khi gia tri X tang dong nghia vdi viec hilu suit BSKK dang v|n hinh tang v i ngfldc lai GSE (8) ' ASE Thay vio cdng thfle (3), co: (6) Kit q u i tinh toan: Vdi cic thdng theo thiet k l cung nhfl cac gii tri dflpc thfle tl, thay vio cic cdng thfle tren, tinh dflpc kit qua nhu trinh bay bang Bdng 1: Kit qud tinh todn lgt gio vd hieu sudt ldm viec ciia thiet bi BSKK X h o n g sd Nhiet khoi dau vao cua B S K K N h i e t d o k h o i d a u r a ciia B S K K Luu luong khoi d3u vao cua B S K K L I I U lugoig k h o i d d u r a c u a B S K K N h i f t d d gio dSu v a o cua B S K K Donvi n n °C •c 135 v^ t/h 540 K t/h 580 T, •c •c 340 N h i e t d o gio dSu cua B S K K Tl T y 16 l o t g i o L GSE Hieu suit p h i a dirdng gio ASE X ISSN 0866 - 7056 TAP CHi CO KHi V I £ T NAM, S6 nam www.cokhivietnam.vn 2016 % % Vo - •c N h i e t d p dircmg k h o i r a k h i k h o n g t i n h d & i lpt gio H i e u s u i t p h i a durong k h d i T y l e hi@u s u i t l a m v i e c c u a t h i d t b i GiA t r i 380 K y hieu 40 6,90 141,55 70,13 88,24 0,79 NGHIEN CO'U-TRAO D | Td cic kit qua thu dflpc cho thiy, ty le Ipt gid v i hilu suit l i m viec cua BSKK la dat yeu cau so vdi chi tieu thiet ke ban diu CAC VAN DE THIET KE BO PHAN CHEN KiN DE GIAM LOT GlO - K H o i TRONG BSKK [4] Rit khd cd phflpng i n cd the chen kin cic BSKK kieu quay, vi nd cd dfldng kinh Idn (cd the len d i n 18 m) va chenh lech Idn nhiet dp gifla cac phin td diu ndng va dau lanh (khoang hPn 200°C), hai ylu td kit hpp khiln rdto hi bien dang nhiet Khdng it trfldng hpp xay hien tflpng cic canh ngoii rotor cua BSKK hi xl xudng d i n hPn cm so vdi d trang thii lanh Do viy, dieu Iden hiln nay, chUa cd cdng nghe nao cd the chen kin dUpc hoan toin bp say khdng Trong khudn khd bai viet nay, nhdm t i c gii de cap den mdt nhdng bien phip Iam kin BSKK hdi nhilt kieu quay Hiln tflpng thay doi khe hd chen kin tai cic vi tri neu trin cd the dan din cp sit gifla phin ddng la cic chi tilt tam chen lap tren rotor quay v i phan tinh l i cac tam chen co dinh lip tren vd rotor v i cac khung b l dd (tim chen re quat) Day la mpt cac nguyen n h i n giy ket d bp say khdng Khi cin chinh khe hd, can thilt phai dilu chinh cic tam chen hfldng kinh dau ndng d trang thai lanh (sP hinh v i hinh 4) de d i m bao khe hd chen dat dflpc dp kin khit v i ddng phang sudt q u i trmh van hinh bd siy khdng 4.1 Sd kit c i u chen kin Di thilt ke cic bd phan chen kin bd say khdng khi, can xac dinh dUpc cac vi tri cin lim kin dfla trin cd sd phin tich hiln tflpng lpt gid xiy BSKK Tren hinh la sd dd md ta cic vi tri cin lam kin cua BSKK Nhu viy: Hinh Sd xac dinh cdc vi tri chen kin cua BSKK kieu quay Tim dita hinh re qu^t - De lam kin hiln tupng lpt gid trflc tilp, can lam kin bang cac bd p h i n chen kin chu vi va bd phan chen hudng kinh d ci hai phia diu ndng vi diu lanh cua BSKK; f zzH Tim ctitn hir/mg kinh - De lam kin hien tfldng Ipt gid cudn theo, can lam kin bang cic bd p h i n chen kin hfldng true cua BSKK 4.2 Xac dinh khe hd cac bo phan chen kin Do cd sfl chenh nhilt dp, nen cd su bien dang nhilt cua rotor va lam rotor cd the gian nd doc true v i phin tam dudi cd t h i bi xe xudng Hinh Sd xac dinh khe hd chen kin theo hUdng kinh d trgng that Ignh Nhflng gia tri bing dfldi diy la tri sd khe hd d trang thii ngupi dflpc tinh toan theo cic thdng so thiet ke dUdi dieu kien tai Id hdi li Idn nhit Trong dd, sP cac khe hd chen kin (A, B, G, H, M, N,R) dflpc md ta tren hinh v i hinh ^ ISSN 6 - 7056 TAP CHi CO KHi VIET NAM, 86 nam 2016 www.colthivietnam.vn NGHlfiN CCfU - TRAO D O I Bdng Gid tri khe hd tgi cdc vi tri chen kin cua BSKK d trgng thai Ignh: Khe lid A B c K D Gia tri (mm) 0,5 20 1,0 5,0 2,0 Khehd G H M N R Gia tri (mm) 10,0 5,0 5,0 2,0 18 4.3 Mdt so k i t qua t h i l t k l cac bd phan chen kin cua BSKK: Theo cac hinh tii d i n Hinh Kit cdu tdm chen hUdng kinh :3E~±i^"'' Hinh Ket cdu tdm chen re quat tl4J sL 129 fi JU _ Zif ^^ "^" - I B L IX - \ ia Tl _— I } ^^LlJLL IJJ Hinh Kit cdu tdm chen chu v ISSN 0866-7056 TAP CHi CO KHi VIET NAM, Sd nam 2016 www.coldiivietnam.vn NGHIEN CLfU-TRAO DOI 4.4 Vat lieu che tao bd phan chen Trin cP sd dieu kiln lam viec cda bp ph^n t i m chen, chpn thep cacbon cd cic nguyin to hpp kim phu hpp bd sung de ning cao tinh nang chiu i n mdn cua thep lam vit lieu che tao O day, chpn vit lieu la thep 09CuPCrNi-A theo tieu chuin GB/T 4171 cua Trung Quoc hoac thep Cup-ten theo tieu chuan JIS cua N h i t Bin cd p h i n hda hpc nhfl Bang va cP tinh theo Bang [2] Bdng 3: Thdnh phdn hoa hgc cua thep 09CuPCrNi-A theo tiiu chudn GB/T 4171: Thanh phan hoa hgc (%) Mac thep Thep 09CuPCrNi-A C Si < 0,250,75 0,12 Mn P S Cr Cu 0,2 - 0,5 0,07-0,15