ELABORATING AND ANALYSING THE REAL BALANCE OF HEAT FOR THE STEAM GENERATOR RGL10/D-D

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1 Annals f te Unversty f Petrşan, Mecancal Engneerng, 10 (2008), ELABORATING AND ANALYSING THE REAL BALANCE OF HEAT FOR THE STEAM GENERATOR RGL10/D-D DAN CODRUŢ PETRILEAN 1 Abstract: Te real termal balance seet was drawn u and te secfc energetc ndexes fr te steam generatr were determned. Keywrds: effcency, balance eat, steam generatr, secfc cmbustble cnsumtn 1. INTRODUCTION Te real balance f eat, fr te steam generatr Ls Internatnal, usng as cmbustble te metane gas wt an nferr secfc eat caacty H = 566 / and te elementary analyss were draw u: CH = 97,91; C 2 H = 0,26; O 2 = 0,21; N 2 = 1,17. Te man functnal arameters, accrdng t te nstructn bk, are: nmnal flw 1250 /; nmnal ressure 7 bar; maxmum ressure 10 bar; steam temerature, accrdng t te saturatn ressure; nut water temerature: 80 C; utut cmney gas temerature: 120 C; cmbustble cnsumtn: 25 /; effcency 0,9%. Te balance utlne ncludes te yscal lmts f te steam bler. Te real termenergetc balance seet was elabrated fr te tme unt. Tere s n reeated ar utsde te steam bler. Te equatn fr te steam bler s balance f eat s: Q c, c + Qc, f + Qa + QL = Qu + Qga, f nc r (1) were: Q c, c - cmbustble s cemcal eat; Q c, f - cmbustble s yscal eat; Q a - yscal eat f te nut water ; Q L -Inut ar eat; Q u - useful eat, equal wt te steam eat f elmnated frm te bler; - yscal eat wastage f te burned Q ga, f 1 Lecturer P.D. Eng, at te Unversty f Petrşan

2 156 Petrlean, D.C. gases; Q nc - wastage trug ncmlete cemcal burnng; Q - wastage trug te bler urge; Q r - wastage caused by radatn and cnvectn. 2. RESULTS Fg. 1. Heats tat ges n and ut f te balance utlne Table 1 resents te cmbustble and ts caracterstcs, and table 2 measurements bulletn. Table 1. Cmbustble and ts caracterstcs Flw caacty, Lwer eatng value, Elementary analyss Cmbustble / /mn CH C2H O2 N2 Metane gas 29, ,91 0,26 0,21 1,17 Table 2. Measurements bulletn fr te steam bler Ls Internatnal Crt Measure elements Symbl UM Value Measurng aaratus Nr. 1 Steam ressure ab bar 7 manmeter 2 Steam temerature t ab C 195 termmeter Steam mass flw m ab / 10 daragm and flwmeter Inut water ressure H2 bar 8,7 manmeter 5 Inut water temerature t H2 C 70 termmeter 6 Cmbustble temerature t cmb C 18 termmeter 7 Cmbustble cnsumtn B / 29,62 gas flwmeter 8 Burned ar temerature t burned ar C 19 termmeter 9 Burned gases temerature t g C 1, gas analyzer Test 50S CO 2 % 8,22 O 2 % 8,11 10 Burned gases cmstn CO mg/m 6 gas analyzer Test 50S NO mg/m 121 NOx mg/m Ar excess λ - 1,5 Gas analyzer Test 50S 12 Blw dwn flw f bler V m / 0, Calbrated fuel tank 1 Burnng effcency ηa - 0,92 Gas analyzer Test 50S 1 Blw-dwn mass flw m / 7,69 Calbrated fuel tank 2 15 Steam bler surface S m 22 - Calculus te balance f eat cmnents: Inut measures: Cemcal eat f te cmbustble:

3 Elabratng and Analysng te Real Balance f Q c, c = ηa B H = 97181, 017 (2) were: η a s te burnng effcency; B urly cmbustble cnsumtn; H eatng value. Pyscal eat f te cmbustble: c, f = B Cc tc = 85, 99 lwer () were te secfc eat f te metane gas (C c ) was determned by te vlume cmstn: Cc = C r = 1,568 ; t c = 18 C (table ) average nut metane mn K gas temerature. Inut ar eat f te steam bler: Q L = V a a =11508, 16 () were V a s te ar flw necessary fr te burnng: m V N a = ( 1+ 0,00161 x) λ B Lmn (5) were L mn s mnmal ar quantty necessary fr burnng. Pyscal eat f te nut water: a = m H 2 O ch 2O th 2O = 91568, 75 (6) were c H2O s secfc eat f te water n K = c, c + c, f + a + L = 10757, 91 (7) Outut measures: Necessary useful eat t rduce lve steam: Q u = m ab ab = , 5 (8) Wastage wt te yscal eat f te burned gases:

4 158 Petrlean, D.C. Q ga, f = V gus B g = 986, (9) Wastage caused by ncmlete cemcal burn: ( H + r H + µ 10 H ) nc = V gu B rc c H 2 H 2 f C = 5228, 1 (10) were: μ f s smke cntent frm te burned gases and CO frm te burnng trangle fr metane s 0,7%. Wastage by bler blw-dwn: = m = 566, 25 (11) Wastage caused by radatn and cnvectn are: ( t t ) Q r = 1,2 S α 0 = 150, 82 (12) were: α s te glbal ceffcent fr eat transmssn: α = m t t 0 ξ C0 + t t 0 t + 27 t Table. Calculated measures used t elabrate te real termal data seet Crt. nr. Measures Symbl UM Value 1 Cmbustble secfc eat C c m K 1,568 2 Inut water entaly c H 2 O Inut water mass flw m Burned ar entaly a 5 Burned ar vlume V a 6 Steam entaly ab 7 Blw-dwn water entaly N K,199 1,5 27,7 15,57 282,75 697,2

5 Elabratng and Analysng te Real Balance f Crt. nr. Measures Symbl UM Value 8 Dry burned gases vlume V mn gus 1,69 m 9 Gases entaly g 10 Glbal ceffcent fr eat transmssn N m 2 K m 2 K α V α 0 Te calculus was made bt fr te rzntal and vertcal surface. 226,25 6,96 76,102 Q v O r = 25067,59 ; r = 168, 2 (1) m surface rentatn ceffcent; ξ relatve emssn ceffcent; C O radatn ceffcent f te black bdy;. Te wall temerature was measured at t = 0 C, and te steam bler rm temerature t 0 = 17 C. e = u + ga, f + nc + + r =10757, 91 (1) Te btaned results are brefly swn n table. Table. Te real balance f eat fr te steam bler Inut measures Value, / % Outut measures Value, / % Q c, c 97181,01 90, Q u ,5 81,62 Q c, f Q ga, f 986, 9,151 Q L 11508,16 1,069 Q nc 5228,1,86 Q a 91568,75 8,512 Q 566,19 0,99 Ttal nuts 10757, Q r 150,82,85 Ttal ututs ,1 100 Energetc ndcatrs fr te steam bler are: - te termal effcency f te steam bler: η t = = 0,816

6 160 Petrlean, D.C. - secfc eat cnsumtn: B H q = m ab = 07, 5. CONCLUSIONS Fg. 2. SANKEY dagram 1. Te raw termal effcency s lwer tan te rject effcency. Ts stuatn s exlaned by te merfect caracter f te burn (CO) and te rased temerature f te utut burn gases, due t te resdue accumulated n te eat excange surfaces f te steam bler. 2. Te adjustment f te burnng s recmmended t cme as clse as ssble t te desgn erfrmances f te burner. REFERENCES [1]. Inel, I., a.., Temenergetcs and Envrnment, Tecncal Publsng Huse [2]. Petrlean, D.C., Te Wrkng Regme Study f te PK-10 Bler frm te Electrc wer Plant frm Parsen, Graduatn Prject, Unversty f Petrsan []. Petrlean, I., Maerean, V., Te Analyze f te Functnal Parameters fr te VK-50-1, Graduatn Prject, Unversty f Petrsan 2001.