Chidzidzo cheUinjiniya cheThermodynamics paMasisitimu eBoiler eIndasitiri
Pendauluan
Maboiler emaindasitiri ndeimwe yemidziyo yakakosha muzvikamu zvakasiyana-siyana—kubva kumafekitori emagetsi nemafekitori emakemikari kusvika kumapuripu nemapepa, uye kunyange indasitiri yezvikafu nezvinwiwa. Basa rayo guru nderekushandura simba remakemikari kubva kumafuta (kana simba remagetsi mumaboiler emagetsi) kuita simba rekupisa, vozoriendesa mumvura kuti ribudise utsi padanho rakati netembiricha. Utsi uhu hunoshandiswa pakupisa, kuomesa, kuuraya utachiona, kana semvura inoshanda neturbine. Kuti system yeboiler ishande zvakachengeteka, zvisina njodzi, uye zvinobudirira, chidzidzo cheinjiniya chethermodynamic chinodiwa, kusanganisira kuenzana kwesimba, kushanda zvakanaka, kurasikirwa nekupisa, uye kuongorora kusadzoreka.
Pfungwa huru dzeThermodynamics muBoilers
Mukutaura nezve thermodynamic, ma boiler anowanzo ongororwa senzira dzekuyerera dzakasimba umo huwandu hwemvura inoyerera hunopinda, hunogamuchira kupisa kubva mukutsva, uye hwobva hwabuda semhepo yakaguta kana kuti mhepo inopisa zvakanyanya. Mutemo wekutanga weThermodynamics wehurongwa hwekuyerera kwakasimba (steady-flow energy equation) unogona kutaurwa zviri nyore:
\[
\dot{Q} – \dot{W} = \dot{m}(h_{out}-h_{in})
\]
Mumaboiler, basa remugodhi (\(\dot{W}\)) rinowanzoregeredzwa nekuti boiler haibudise basa remakanika zvakananga. Masimba ekinetic neanogona kushandiswawo madiki zvichienzaniswa nekuchinja kwe enthalpy, saka equation inoshanda inova:
\[
\dot{Q} \approx \dot{m}(h_{steam}-h_{fw})
\]
Apa ndipo panowanikwa enthalpy. Data remvura nemhepo inoyerera inowanikwa kubva pamatafura emhepo inoyerera kana madhayagiramu eMollier (h–s). Mvura inoyerera padanho rakati inogona kunge iri mvura inotonhorera, nepo mvura inobuda inogona kunge iri mhepo yakaoma yakasviba, mhepo yakanyorova (ine mhando yemhepo inoyerera x), kana mhepo inopisa zvakanyanya.
Maitiro ekupisa mvura kuita utsi
Panyaya yekupisa mvura muboiler, kupisa mvura muboiler kunopfuura nematanho akati wandei:
1. Kudziisa mvura nepachikafu (kudziisa zvine musoro)
Mvura inokwidzwa mukupisa kubva pakupinda kusvika pakupisa kwakazara pakushanda. Simba rinodiwa rinoenderana nekukwanisa kupisa uye kuwedzera kwekupisa.
2. Kubuda kwemvura (kuchinja kwechikamu / kupisa kwakavanzika)
Pakusvika pakuzara kwemvura, kuwedzerwa kwekupisa kunokonzera kuchinja kwechikamu kubva pamvura kuenda kumhepo. Muchikamu chino, tembiricha inoramba yakafanana, asi enthalpy inowedzera zvakanyanya nekuda kwekupisa kwakavanzika kwekuvapo kwemvura.
3. Kupisa zvakanyanya (kana paine superheater)
Mhute yakaguta inodziiswazve kuti ikwidze tembiricha yayo pamusoro petembiricha yakaguta padanho rimwe chete. Kupisa kwakanyanya kunowedzera enthalpy uye kunoderedza hunyoro hwemhute, izvo zvinobatsira pakushandiswa kweturbine uye kushanda zvakanaka kwemaitiro.
Mumagadzirirwo emabhaira emazuva ano, kudzoreredza kupisa kunowanzo wedzerwa nezvimwe zvinhu zvakaita se economizers (feedwater heaters), air preheaters (combustion air heaters), uye superheaters. Chimwe nechimwe chine chinangwa chekuderedza kurasikirwa kwema stack uye kuwedzera kushanda zvakanaka kwekutamisa kupisa.
Kuenzanisa Kwesimba uye Kushanda Nesimba Kwebhoyira
Kushanda zvakanaka kwebhoyira kunowanzotsanangurwa sehuwandu hwesimba rinobatsira rinotorwa nemvura/utsi nesimba remakemikari remafuta anopiswa. Nzira mbiri dzakakurumbira ndeidzi:
1. Nzira yakananga (nzira yakananga / nzira yekuisa-kuburitsa)
\[
\eta_{boiler}=\frac{\dot{m}_{steam}(h_{steam}-h_{fw})}{\dot{m}_{fuel}\times LHV}\times 100\%
\]
NeLHV (Lower Heating Value) kana HHV (Higher Heating Value) zvichienderana nechiyero chinoshandiswa.
2. Nzira isina kunanga (nzira yekurasikirwa nekupisa)
Kushanda zvakanaka kunoverengerwa kubva pa100% kubvisa kurasikirwa kwekupisa kwese, semuenzaniso:
- Kurasikirwa negasi rinobuda mugomba rakaoma
- Kurasikirwa kunokonzerwa nemhepo inopfuta kubva mukupisa kwehydrogen
- Kurasikirwa nekuda kwemafuta nemhepo inonyorova
- Kurasikirwa nekuda kwekabhoni isina kupiswa
- Kurasikirwa nemwaranzi uye kudonha kwemhepo kubva pamusoro pebhoyira
- Kurasikirwa nekuputika
Nzira dzisina kunanga dzinowanzo shandiswa pakuongorora simba nekuti dzinobatsira kuona nzvimbo huru dzinokonzera kusashanda zvakanaka.
Kurasikirwa Kukuru Kwekupisa Mukushanda Kwebhoyira
Chidzidzo chakanaka chethermodynamic hachigumiri pakuverenga zvinobuda-zvinoiswa, asi chinoratidzawo kurasikirwa nesimba kukuru.
1. Kurasikirwa kwematanda (kurasikirwa nechimney)
Magasi anobuda mumhepo anopisa ane enthalpy yakakura. Kuedza kuderedza izvi kunogona kuitwa nekushandisa ma economizers nema air preheaters, asi kungwarira kunofanira kuitwa kuti asapfuure acid dew point (kunyanya mafuta ane sulfur) kudzivirira ngura.
2. Kuputika kwemvura
Kudzikisa mvura kunodiwa kudzora huwandu hwezvinhu zvakanyungudutswa (TDS) mudhiramu rebhoyira. Zvisinei, kubviswa kwemvura inopisa iyi kunoreva kurasikirwa ne enthalpy. Sisitimu yekudzoreredza kupisa inodzikisa mvura inogona kushandisa kupisa uku kudziisa mvura inoyerera kana mvura yekubika.
3. Mhepo yakawandisa uye kupisa kusina kukwana
Mhepo yakawandisa inodiwa kuti pave nekubvira kwakasimba, asi mhepo yakawandisa inowedzera huwandu hwegasi remvura inoyerera, zvichiwedzera kurasikirwa kwemurwi. Kusiyana neizvi, mhepo isina kukwana inokonzera kuwedzera kweCO2 nemafuta asina kupiswa—zvose zvinokuvadza. Kugadzirisa kunowanikwa kuburikidza nekudzora O₂/CO2 gasi remvura inoyerera uye kugadzirisa burner.
4. Kupenya uye kutenderera kwemhepo kubva pamusoro
Kusadzivirira kupisa zvakanaka kunowedzera kurasikirwa nekupisa kunharaunda. Kuvandudzwa kwekupisa kunokonzerwa nekusadzivirira kupisa uye kunodzivirira kupisa kunowanzo kanganisa kushanda zvakanaka uye kuchengetedzeka.
Kuongorora Kushanda Kwemuviri: Kuongorora Hunhu hweSimba
Pamusoro pesimba (Mutemo I), thermodynamics yemazuva ano yeinjiniya inowanzoshandisa ongororo yekusimbisa simba kuti iongorore "hunhu" hwesimba uye kusachinjika (Mutemo II). Exergy inotsanangura basa guru rinogona kuwanikwa kana sisitimu ikaunzwa mumamiriro ayo ekunze.
Mumaboilers, kusachinjika kukuru kunoitika pa:
- Maitiro ekutsva (maitiro emakemikari uye kusanganiswa pakupisa kwakanyanya)
- Kutamiswa kwekupisa kune musiyano mukuru wekupisa, semuenzaniso pakati pemurazvo nepamusoro pepombi
- Kukweshana kwemvura pamativi egasi nemvura/mhepo (kuderera kwesimba remhepo)
Nekuongorora kwesimba, vashandi vanogona kuona kuti kunyange zvazvo kumwe kupisa kuri kuendeswa mumvura, hunhu hwesimba hunoderera nekuda kwekusagadziriswa kwemaitiro acho. Izvi zvinobatsira kukoshesa kuvandudzwa: semuenzaniso, kuvandudza kugoverwa kwemafuta emhepo, kuwedzera kudzoreredzwa kwekupisa, kana kuderedza ΔT yakakwira zvakanyanya muheat exchanger.
Mhedzisiro yeMamiriro Ekushanda paKushanda Kwekupisa
Kushanda kwebhoyira kunonyanya kukonzerwa nekumanikidzwa, tembiricha uye hunhu hwemvura.
1. Kumanikidzwa kwekushanda
Kuwedzera kumanikidzwa kunowedzera tembiricha yekuzara. Kune zvimwe zvinodiwa pakuita, izvi zvinogona kuwedzera huwandu hwesimba remhepo. Zvisinei, kumanikidzwa kwakakwira kunoda zvinhu zvakasimba uye kudzora kwakasimba.
2. Tembiricha yemvura yekudyisa
Kana tembiricha yemvura yekudya yakakwira, bhaira rinoda kupisa kushoma kuti riwane mamiriro eutsi anodiwa. Saka, deaerator uye economizer zvine basa guru.
3. Hunhu hwemvura (kurapwa)
Mwero weokisijeni yakanyungudutswa, kuomarara, uye TDS zvinopesvedzera kukura uye ngura. Kukura kunowedzera kuramba kupisa, zvichikonzera kutamiswa kwekupisa kusina kunaka, tembiricha yesimbi yakawedzera, kudzikira kwekushanda zvakanaka, uye njodzi yekutadza kushanda zvakanaka kwemachubhu.
Nzira yekuvandudza kushanda zvakanaka inobva paThermodynamics
Mamwe matanho anoshanda ane chekuita zvakananga nekudzidza kwethermodynamics anosanganisira:
- Kuisa/kugadzirisa economizer kuti ishandise kupisa kwegasi rinobuda muutsi kupisa mvura yemumba.
- Chidziisa chemhepo chinowedzera tembiricha yemhepo inobvira, chinovandudza kugadzikana kwemurazvo uye kushanda zvakanaka.
- Kudzora O₂ trim kuti mhepo yakawandisa irambe yakachena.
- Kugadzirisa kupisa kwemhepo uye kugadzirisa kupisa kuti uderedze kurasikirwa ne enthalpy.
- Kugadzirisa nzvimbo yekutamisa kupisa (kuchenesa soot/scale) kuti coefficient yekutamisa kupisa irambe yakakwira.
– Kudzivirira zvakanaka papombi dzemhepo, madhiramu nemagoko.
- Kuramba uchitarisa ma parameter e thermodynamic (T, P, flow rate, O₂/CO2 flue gas) kuti uone kana paine kutsauka kuripo.
Mhedziso
Chidzidzo cheinjiniya chethermodynamics mumaindasitiri emabhaira chinopa hurongwa hwakasimba hwekuongorora kuti simba rinobva mumafuta rinoshandurwa sei kuita steam, ukuwo richionawo nzvimbo dzekurasikirwa dzinoderedza kushanda zvakanaka. Nekushandisa simba rakaringana (Mutemo Wekutanga) uye kuriwedzera nemaonero ekushandisa simba (Mutemo Wechipiri), mainjiniya vanogona kuita sarudzo dzinotungamirirwa nedata kuti vawedzere kushanda zvakanaka, vaderedze kushandiswa kwemafuta, vachengetedze kuvimbika kwemidziyo, uye vawedzere hupenyu hwebasa rebhaira. Pakupedzisira, bhaira rakagadziriswa nethermodynamic haringodziviriri mari chete asiwo rinotsigira kudzikiswa kweutsi uye mashandiro emaindasitiri anogara kwenguva refu.
