Journal of ower and Energy Engineering, 015, 3, 1-14 ublihed Online Augut 015 in SciRe. http://www.cirp.org/journal/jpee http://www.cirp.org/journal/aperinformation.apx?doi=10.436/jpee.015.38001 Improved Deign of a 5 MW Ga urbine lant Uing ombined ycle Application Barinaadaa haddeu Lebele-Alawa, Anthony Kpegele Le-ol Department of Mechanical Engineering, River State Univerity of Science and echnology, ort Harcourt, Nigeria Email: lebele-alawa.thaddeu@ut.edu.ng, le-ol.anthony@ut.edu.ng Received 5 June 015; accepted 18 July 015; publihed 1 July 015 opyright 015 by author and Scientific Reearch ublihing Inc. hi work i licened under the reative ommon Attribution International Licene ( BY). http://creativecommon.org/licene/by/4.0/ Abtract hi paper preent the improved deign of a 5 MW ga turbine power plant at Omoku in the Niger Delta area of Nigeria, uing combined cycle application. It entail retrofitting a team bottoming plant to the exiting 5 MW ga turbine plant by incorporating a heat recovery team generator. he focu i to improve performance a well a reduction in total emiion to the environment. Direct data collection wa performed from the HMI monitoring creen, log book and manufacturer manual. Employing the application of MALAB, the thermodynamic equation were modeled and appropriate parameter of the variou component of the team turbine power plant were determined. he reult how that the combined cycle ytem had a total power output of 37.9 MW, made up of 5.0 MW from the ga turbine power plant and 1.9 MW (an increae of about 51%) from the team turbine plant, having an HRSG, condener and feed pump capacitie of 4.46 MW, 9.61 MW and 1.76 MW repectively. he condener cooling water parameter include a ma flow of 1180.4 kg/, inlet and outlet temperature of 9.8 and 35.8 repectively. he cycle efficiency of the dry mode ga turbine wa 6.6% wherea, after modification, the combined cycle power plant overall efficiency i 48.8% (about 84% increae). Hence, SIEMENS team turbine product of MODEL: S-150 wa recommended a the team bottoming plant. Alo the work reveal that a heat flow of about 4.46 MW which wa otherwie being wated in the exhaut ga of the 5 MW ga turbine power plant could be converted to 1.9 MW of electric power, thu reducing the total emiion to the environment. Keyword Ga urbine, Steam urbine, HRSG, ombined ycle, ower Output, Overall Efficiency, ondener ooling Water How to cite thi paper: Lebele-Alawa, B.. and Le-ol, A.K. (015) Improved Deign of a 5 MW Ga urbine lant Uing ombined ycle Application. Journal of ower and Energy Engineering, 3, 1-14. http://dx.doi.org/10.436/jpee.015.38001
1. Introduction Energy i a baic requirement for human exitence, and thu a driving force of civilization a almot all of our everyday activitie and productive procee involve energy in one form or another [1]. he economic development and living tandard of any ociety i a function of the availability and acceibility of electrical power to her. herefore, the acknowledgement of the importance of increaing acce to commercial electricity i fundamental for the future and utainable development of any ociety []. he increaed world population and the quet to improve living condition a well a global economic growth have reulted in a continuou increae in energy demand [3]. Accommodating the projected increae in energy demand mut be approached with caution a it i now generally accepted that human activitie uch a burning of foil fuel involved in energy ytem are the main ource of acid rain and greenhoue gae which are the major contributor to global climatic change [4]. Yadav [5] in hi work, oberved that one of the greatet challenge facing humanity during the twenty-firt century i that of giving everyone on the planet acce to afe, clean and utainable energy upplie. Anheden [6] did a tudy on the analyi of ga turbine ytem for utainable energy converion and uggeted that one way to provide the energy ervice demand by the growing population, and yet reduce the O emiion, i to increae the energy converion efficiency of exiting and future energy converion procee by variou technological advancement. Nkoi et al. [7] in their work on invetigation encompaing comparative aement of ga turbine (G) cycle optional alo oberved that a modified ga turbine cycle configuration incorporating unconventional component uch a engine cycle with low preure compreor (L) zero-taged, recuperated engine cycle, and intercooled/recuperated (IR) engine cycle exhibited better performance in term of thermal efficiency and pecific fuel conumption than the traditional imple cycle engine. A tudy on power increae and economical reult of different efficiency improvement method ha revealed that fogging and evaporative method are the mot effective method of efficiency improvement in Khoramhahr power plant [8]. Severally, there have often been uggetion from literature of the combination of two or more thermal cycle within a ingle power plant with the intention of increaing efficiency over that of ingle cycle. In a tudy on the performance of combined ga turbine-team cycle for power generation, it wa noted that thermal procee can be combined in thi way whether they operate with the ame or with differing working media. he tudy concluded that a combination of cycle with different working media a in combined cycle i more intereting becaue their advantage can complement one another [9]. Korobityn [10] in hi analyi of cogeneration, combined and integrated cycle oberved that improved efficiency can be achieved by modification to the original imple cycle to recover heat from the turbine exhaut for generation of team in a team turbine bottoming cycle a found in combined cycle. A combined cycle power plant () i a power plant where electricity production i done from the combination of both ga and team turbine. reviou work ha been done on rotor-blade profile influence on a ga compreor effectivene. he tudy tated that in the ga turbine, atmopheric air i drawn in through an intake duct and compreed to a high preure in the compreor coniting of a cacade of everal tage of blade located on a ingle axle in radial form [11] [1]. he high preure air i delivered to the combutor where fuel i prayed and the high preure and temperature product of combution impinge on the turbine blade which rotate the haft that drive an electrical generator to produce electricity and the exhaut ga energy from the ga turbine i ued to generate team in a heat recovery team generator (HRSG) which then produce more electricity from a team turbine. here i a great potential for increaed power output and efficiency, a well a reduction of emitted pollutant to the environment, in energy converting device by recovering wate heat to a greater extent. It wa oberved that the development of combined cycle power plant i the mot efficient and effective effort in thi direction. hi i gaining increaing acceptance a an alternative to conventional ga or team cycle due to high thermal efficiency of about 60% utilizing natural ga a fuel [5]. Ragland et al. [13] did a tudy on combined cycle heat recovery optimization and oberved that combution turbine performance ha the primary impact on combined cycle plant efficiency and the next mot important piece of equipment that impact efficiency i the heat recovery team generator (HRSG). he tudy continued that in the deign of, the HRSG parameter to optimize include team preure, temperature, flow, pinch point, approach temperature and HRSG exit ga temperature. he HRSG i a heat exchanger compriing three component namely the economizer, the evaporator, and the uperheater and can be deigned with typical configuration of ingle-preure or multiple-preure level, with or without upplementary firing. In a tudy on the
optimization of Maputo power plant, it wa oberved that the mot important deign parameter of a team turbine i the team data which include the ma flow and the team turbine input preure and temperature, a well a the condener preure [14]. o effectively harne heat from the HRSG o a to have a higher combined cycle thermal efficiency, the tack temperature hould be reduced a much a poible but not below the acid dew point of the flue ga to avoid level of condenation. Acid dew point of exhaut ga i within the range of 104-160 [15]. In a tudy on combined cycle ga and team turbine power plant, the typical team turbine outlet preure in condening mode range from 0.03 to 0.5 bar [16] while Aref [17] in hi work on development of framework for thermo-economic optimization of imple and combined ga turbine cycle indicated that pinch point i uually between 8 and 15 and approach temperature i in the range 8-1. hi paper conider an improved deign of the Omoku ga turbine power plant uing combined cycle application, with the aim of increaing it performance (power output and efficiency) a well a reducing the total emiion to the environment. It analyze a uitable HRSG capable of producing team at an effective preure which will utilize the exhaut ga from the ga turbine to power the team turbine. he Omoku ga turbine i located in the Niger Delta area of Nigeria. It ha ix (6) unit, each coniting of a ga turbine for electricity generation of 5 MW and exhaut ga temperature of 487. he manufacturer of the ga turbine ytem i General Electric (GE) and it i an MS 5001 (GE Frame 5), ingle haft model having a double bu ingle breaker; 3 80 MVA tranformer and a 33 kv to 13 kv line witchyard ytem which i capable of evacuating 00 MW of power [18]. It i oberved that the hot exhaut ga from the Omoku ga plant i vented to the atmophere, a common to all conventional open cycle ga turbine; hence, coniderable amount of heat energy goe a wate with the exhaut of the ga turbine, thu, contributing to environmental pollution. Rather than flaring the hot exhaut ga from thi Brayton cycle plant, thi heat can be utilized for other ueful purpoe uing heat recovery team generator (HRSG). hi reaon prompted the need for the improved deign of the Omoku ga turbine power plant to a combined-cycle ytem uch that the otherwie wated heat from the hot exhaut ga i captured and channeled into the HRSG and ued to generate team to drive another generator (team generator) to produce more electricity, thu improving the performance (increaed total output and efficiency) with le environmental pollution compared to the ingle cycle turbine plant. Hence, a combined cycle power plant () uually conit of a Ga turbine plant, a HRSG and a Steam turbine plant. he ga turbine plant operating on Brayton cycle and the team turbine plant operating on rankine cycle are often called topping and bottoming cycle repectively [19]. A common to all conventional, thi modification require a ource of cooling water to be utilized in the condening unit of the propoed team turbine ytem. However, it i intereting to know that there i a flowing river cloe to the Omoku ga plant which enhance the availability of water ource for thi purpoe, jutifying the feaibility of the tudy.. Material and Method he reearch methodologie adopted are a follow: 1) Data collection of the Omoku Ga turbine power plant (GE FRAME 5 MS 5001 A Single Shaft) from direct obervation from the monitoring creen of the human machine interface (HMI), log book and manufacturer manual. ) Aement of the current plant condition. 3) MALAB oftware wa ued to model the tandard thermodynamic relation and equation for the analyi of the turbo-machinery component of the ga turbine to determine the heat energy rejected in the exhaut ga of the exiting plant o a to acertain the correponding power that can match with the exhaut ga temperature (EG). 4) Determination of a uitable capacity (izing) of a heat recovery team generator (HRSG). 5) From the relevant deign calculation, the capacitie of other component of the propoed team turbine ytem were determined. hey include the turbine, condener, boiler and feed pump. Hence the team turbine component that will match with the exiting ga turbine were elected. 6) he power output and efficiency of the team turbine, hence, power output and efficiency of the combined cycle ga turbine plant were determined. able 1 diplay the neceary data required for the performance analyi of the power plant which equally 3
erve a the input data for the deign/converion to a combined cycle. Alo, the ambient condition of the phyical environment of the plant vicinity were noted..1. Analytical Model of the ombined Ga and Steam th g.1.1. erformance of a heoretical Heat Balance on HRSG hi will give u the relationhip between the tube ide and hell ide procee. It i alo important that tube ide component which will make up the HRSG unit be decided. Even though thee component may include other heat exchange ervice, at thi time we will only conider the three primary coil type namely; Economizer, Evaporator and Super heater a hown in Figure 1. From Figure 1, the team temperature increae form point 4 to 1. roce 4-5 occur in the economizer; 5-6 occur in the evaporator, and 6-1 i uperheating. he exhaut ga i cooled from point d of the ga turbine to a temperature of a well above it acid dew point temperature. he pinch point are x-5 and d-1. A pinch and approach temperature of 10 i ued in order to able 1. Average operating data for Omoku ga turbine plant. omponent arameter Symbol Unit Value urbo compreor ombution chamber Ga turbine Other data emperature Inlet temperature 1 30.4 Outlet temperature 367 Inlet preure 1 bar 1.013 Outlet preure bar 10 Ma flow rate (Air) Fuel conumption (flow rate) a kg/ 1.9 f kg/ 1. Inlet temperature 3 959 Outlet temperature 4 487 Exhaut ga flow (flow rate of ga) G hermal efficiency G ower output eg kg/ 14.1 thg % 6.6 g MW 5 G Exhaut-in Super heated Steam- outlet d 1 x inch temp. Approach temp. 6 team aturation temp. 5 a Stack temp. Super heat Latent heat Senible heat 4 Feed water in Heat tranfer SUER HEAER EVAORAOR EONOMIZER Figure 1. Variation of heat flow with temperature between exhaut ga and HRSG. 4
minimize heat lo between exhaut ga and team and at the ame time enure heat tranfer for maximum power output. Applying the heat balance equation between the ga turbine exhaut and HRSG a given below: Heat rejected by exhaut ga i given by ( ) = ( ) h h c (1) 1 4 eg peg d a ( ) = ( ) h h c () 5 4 eg peg x a ( ) Q = c (3) eg eg peg d a where; m = Ma flow rate of team in kg/ m eg = Ma flow rate of exhaut ga in kg/ a = ooling temperature of exhaut ga (HRSG tack temperature) x = emperature of exhaut ga at pinch point d = emperature of exhaut ga at ga turbine outlet m eg = Specific heat of exhaut ga he capacitie of the variou component of the HRSG are thu etimated a follow: Economizer: Evaporator: Superheater: HRSG capacity: Heat Lo hermal Efficiency of HRSG, ( ) Q = Q = h h (4) ec egec eg 5 4 ( ) Q = Q = h h (5) ev egev eg 6 5 ( ) Q = Q = h h (6) h egh eg 1 6 QHRSG = Qec + Qev + Qh (7) H = Q Q (8) L eg HRSG Q HRSG HRSG = (9) Q eg.1.. Determination of Net ower Output at Generator erminal of Steam urbine he actual power developed by the team turbine can be calculated from the relation: Ientropic efficiency Steam turbine net power output where he team turbine cycle efficiency i ( actual) ( ientropic) ( 1 ) 1 h h = = h h ( actual) NE p ( ) 1 (10) = (11) ( ) ( ) = pump power input actual = h h (1) p 4 1 3 5
NE = (13) QHRSG he capacity of a team plant i often expreed in term of team rate or pecific team conumption (S.S.). Nag defined it a the rate of team flow kg/ required to produce unit haft output (1 kw) [19] Specific Steam onumption (SS) Where W net = pecific network output Specific team turbine work Specific ump Work Net pecific work ( kg kw h) S.S. = 1 Wnet (14) W = W p ( actual) (15) p = (16) WNE = W W (17) he condener cooling water ytem heat tranfer (heat rejected to the condener) give ( ) Q = h h (18) 3 Applying the energy balance equation between the condener and the cooling water; ( ) ( ) = c t t = h h (19) w pw out in 3 he condener Efficiency, = cond Where; m = Ma flow rate of team in kg/ m w = Ma flow rate of cooling water c p w = Specific heat of water t in = emperature of cooling water into condener t out = emperature of cooling water out of the condener = ondener aturated temperature Actual temp.rie of cooling water maximum temp.rie of cooling water cond t = out t t in in (0).1.3. ombined Ga and Steam he combined-cycle unit combine the Rankine (team turbine) and Brayton (ga turbine) thermodynamic cycle uing HRSG. he HRSG compriing the economizer, the evaporator, and the uperheater, trapped the energy in the exhaut gae of the turbine to generate team for the team turbine to generate more power. he chematic diagram are hown in Figure and Figure 3. From Figure : Omoku Ga turbine ycle a b c d a Steam urbine ycle 1 3 4 1 roce 4 1 i the heat tranfer proce from exhaut ga of ga turbine to the Heat Recovery Steam Generator of the Steam turbine part. he combined-cycle overall efficiency and power output are given by: = + g g (1) 6
Stack Ga Fuel Sprayed Heat Recovery Steam Generator ombution hamber Generator ompreor urbine urbine Generator ondener Air Inlet ooling Water Feed ump GAS URBINE Figure. Schematic diagram of combined ga and team cycle. EAM URBINE emperature 0 959 c 0 W g 367 330 b b 1 Q 1 d d 1 487 49 W Q 1 30.4 W a 5 4 4 1 6 W 3 Q 3 1 Figure 3. ombined ga and team cycle power plant on -S diagram. = + g () where and are combined cycle overall efficiency and power output repectively. = Steam turbine power output, g = ga turbine power output = Steam turbine thermal efficiency Entropy (S) kj/kgk 7
g = Ga turbine thermal efficiency.. HRSG and Steam urbine Deign Analyi Ragland et al. [13] in hi tudy on combined cycle heat recovery optimization indicated that a a general guideline in the deign of combined cycle power plant (), the ga turbine will repreent 66% of the plant electrical output auming that the HRSG doe not employ a duct burner. he remaining output will be upplied by the team turbine. hi implie that for the Omoku ga turbine power plant having a capacity of 5 MW, the required output of the propoed combined cycle power plant will be 37.9 MW (whoe 66% give the 5 MW of the exiting Omokuga turbine) and the remaining output will be upplied by the team turbine which i 34% of the. Hence, the power output of the team turbine that will match the exiting Omoku ga turbine i 1.9 MW. A ingle preure HRSG without upplementary firing i employed in thi deign. A pinch point and approach temperature of 10, and a condener preure of 0.1 bar were ued in thi work while the exhaut ga cooling temperature (HRSG tack temperature) wa choen above 160 to avoid condenation of the exhaut ga at it acid dew point. For the purpoe of thi deign, the inlet temperature difference between the condener and the cooling water i taken a 16 and the pinch point of 10 i taken a the exit temperature difference reulting to a cooling water temperature rie of 6 i choen. o arrive at the required team turbine capacity of 1.9 MW reulting to a more efficient combined cycle ytem with increaed output, MALAB oftware wa ued to model the thermodynamic equation, and appropriate parameter of the variou component of the team turbine power plant were determined conidering Nine (9) different condition of iterating the team aturation preure from 0 bar to 50 bar and HRSG tack temperature within the range of 170 to 190, in applying the pinch technology for the HRSG and team turbine analyi and the reult i preented in able. 3. Reult and Dicuion 3.1. Reult In order to determine the combined cycle component, all parameter were determined uing the MALAB model. he ummary of the reult obtained are hown in able. 3.. Dicuion able give the reult of the analyi after nine iteration. Iteration 1, 3 & 7 how that a the aturation preure increae from 0 bar - 40 bar and HRSG tack temperature increae from 170-190, the team turbine net power output increae by 13.% and the combined cycle overall efficiency increae by 6.%. hi indicate that a imultaneou increae in team aturation preure and tack temperature improve the combined cycle power output and efficiency. Iteration, 3 & 6 how that a the tack temperature increae from 170 to 190 at contant aturation preure of 30bar, the team turbine net power output decreae from 13.5007 MW to 10.6399 MW and the combined cycle efficiency decreae from 48.4805% to 44.9933%. hi indicate that for every 0 increae in the tack temperature, the turbine net power output and efficiency decreae by 1% and 7.% repectively. he 3 rd to 5 th iteration how that a the aturation team preure increae from 30 bar to 40 bar at contant HRSG tack temperature of 180, the team turbine net power output increae from 1.0690 MW to 13.6630 MW and the combined cycle efficiency increae from 46.793% to 49.4494%. hi how that for every 10 bar increae in the aturation team preure, there exit about 13.% increae in the team turbine net power output (which in turn increae the combined cycle power output) and 5.7% increae in the combined cycle efficiency. Iteration 6-9 how that at contant HRSG tack temperature of 190, increae a the aturation preure increae. It indicate that for every 0 increae in the aturation preure, the increae by 8%. hi behaviour i repreented in Figure 4. Figure 5 repreent the variation of combined cycle efficiency with aturation preure at different HRSG tack temperature. It how a progreive increae in the combined cycle efficiency with increae in team preure and HRSG tack temperature to about 45 bar, 190. Further increae in the team preure at the tack temperature how a decline in the overall cycle efficiency. It therefore indicate that for the modified deign 8
9 B.. Lebele-Alawa, A. K. Le-ol
ombined ower Output (MW) 39 38.5 38 37.5 37 36.5 36 35.5 35 = 0.001(S) + 0.57(S) + 9.1 0 10 0 30 40 50 60 Saturation reure (bar) Figure 4. Variation of combined cycle power output with aturation preure at contant HRSG tack temperature of 190. 60 ȵ= 0.033(S) +.579(S) 0.334 50 ombined ycle Efficiency % 40 30 0 10 0 0 10 0 30 40 50 60 Saturation reure (bar) Figure 5. Variation of combined cycle efficiency with aturation preure at different HRSG tack temperature. proce, a team aturation preure of 45 bar and HRSG tack temperature of 190 i ued a the maximum limiting condition. Figure 6 how the variation of team turbine power output with aturation preure at different HRSG tack temperature. It how that the maximum team power i generated at the aturation preure of 35 bar and HRSG tack temperature of 180. Again, obervation from iteration, 3 & 6 how that at contant aturation team preure and increaed HRSG tack temperature from 170 to 190, the HRSG capacity decreae from 45.3188 MW to 4.4575 MW a preented on Figure 7. hi how that for every 1 increae in the tack temperature at a contant aturation preure of 30 bar, the HRSG capacity decreae by 0.3%. It i an indication that for higher HRSG capacity, the tack temperature hould be within a coniderable average value. hi i repreented in Figure 7. A previouly tated, a team turbine capacity rating 1.9 MW (34% of the required ) i required to 10
Steam urbine ower output 14.7 14.68 14.66 14.64 14.6 14.6 14.58 14.56 14.54 14.5 = 0.000(S) + 0.03(S) + 14.14 0 10 0 30 40 50 60 Saturation reure (bar) Figure 6. Variation of team turbine power output with aturation preure at different HRSG tack temperature. 45.5 Q hrg = 0.143() + 69.6 HRSG Heat apacity (MW) 45 44.5 44 43.5 43 4.5 4 165 170 175 180 185 190 195 Stack emperature ( ) Figure 7. Variation of HRSG capacity with tack temperature. able 3. Steam cycle pecification for combine cycle. HRSG Stack temperature, = 190 a Saturation temperature in Evaporator = 57.1 5 inch point temperature difference 10 HRSG capacity Q = 4.46 HRSG Steam urbine Generator = t pp oweroutput = = 1.85 MW 1.9 MW gen NE hermal efficiency gen = 30% ondener ooling Water arameter Inlet temperature t = 9.8 Outlet temperature t = 35.8 out Ma flow rate m = 1180.4 kg ondener efficiency cond = 37.50% w in Inlet temperature = 467 1 EAM URBINE Steam aturation preure = 45 bar 1 Ientropic efficiency = 89.06% i hermal efficiency = 30.5% th oweroutput ( actual) = 14.61 MW Ma flow rate m = 13.747 kg Specific team conumption S.S. = 3.85 kg kw h Steam outlet preure (condener preure) = 0.1 bar ondener capacity Q = 9.61 MW 3 Feed pump capacity = 1.76 MW ombined ycle Analyi Overall power output = 37.9 MW Overall efficiency = 48.81% 11
match the exiting Omoku ga turbine of 5 MW (66% of the required ), making it a combined cycle power plant () of 37.9 MW capacity. able 3 how the detailed pecification of the required 1.9 MW capacity team turbine (attained from the 8 th iteration of able ) for the combined cycle power plant. he team turbine thermal efficiency i determined to be 30.5%, with HRSG capacity of 4.46 MW which i equivalent to the heat rejected by the exhaut ga except for a lo of 0.0001 MW. It alo how the condener and feed pump capacitie to be 9.61 MW and 1.76 MW repectively, and pecific team conumption (S.S.) of 3.85 kg/kwh, indicating that a team rate of 0.064 kg/ i required for every 1 kw of haft output. Again, reult preented in able 3 how that for the team turbine capacity of 1.9 MW, to enhance condenation proce, the cooling water enter the condener at 9.8 and leave at 35.8, indicating an actual cooling water temperature rie of 6 and a maximum cooling water temperature rie of 16 reulting to a condener efficiency of 37.5%. he cooling water flowing at 1180.4 kg/ with the team ma flow of 13.75 kg/ indicate that for every kg of team condened, 85.55 kg of cooling water i required. hu, to meet the huge demand of water, the power plant hould be located where there i urplu water upply. Deduction from all the analyi and dicuion reult to a combined cycle power output of 37.9 MW and an overall efficiency of 48.8%. hi higher efficiency of the combined cycle achieved compared with that of the dry mode Omoku ga turbine indicate that the amount of emiion dicharged into the atmophere per unit ma of fuel burnt i le. 4. oncluion he Omoku ga turbine power plant deign ha been improved from a imple cycle operating on a dry mode to a combined cycle operation by retrofitting a team bottoming plant through the incorporation of a HRSG. hi produce additional electric power of 1.9 MW (an increae of about 51%) from team power plant to the exiting 5 MW of the preent ga turbine power plant, making a total power output of 37.9 MW for the combined cycle power plant; the team turbine plant having a HRSG, condener and feed pump capacitie of 4.46 MW, 9.61 MW and 1.76 MW repectively. he condener cooling water parameter include a ma flow of 1180.4 kg/, inlet and outlet temperature of 9.8 and 35.8 repectively with a condener efficiency of 37.5%. Moreover, the converion increae the efficiency of the Omoku ga turbine power plant from 6.60% to 48.81% of the combined cycle power plant. Baed on the above parameter, SIEMENS team turbine product of MODEL: S-150 wa recommended a the team bottoming plant. It i thu dicovered that a heat flow of about 4.46 MW which wa otherwie being wated in the EG of the dry mode engine of the Omoku ga turbine could be converted to 1.9 MW of electric power thu, reducing the total emiion to the environment. In effect, the plant performance i enhanced. Reference [1] Rao, S. and arulekar, B.B. (007) Energy echnology: Non-onventional, Renewable and onventional. Khanna ubliher, Naiarak, Delhi. [] Mohamed, K.M. (005) arametric Analyi of Advanced ombined ower Generation Sytem. M.Sc. hei, Univerity of New Brunwick. [3] German Adviory ouncil on Global hange (WBGU) (011) World in ranition-oward Sutainable Energy Sytem. http://www.wbgu.de [4] Gowami, D.Y. and Kreith, F. (008) Energy onverion. R re, aylor & Franci Group, Boca Ranton, London, New York. [5] Yadav, R. (009) Steam and Ga urbine and ower lant Engineering. entral ublihing Houe, Allahabad. [6] Anheden, M. (000) Analyi of Ga urbine Sytem for Sutainable Energy onverion. h.d. hei, Royal Intitute of echnology, Stockholm. [7] Nkoi, B., ericle,. and heorkli, N. (013) erformance Aement of Simple and Modified ycle urbohaft Ga urbine. ropulion and ower Reearch,, 96-106. http://dx.doi.org/10.1016/j.jppr.013.04.009 [8] Epanni, R., Ebrahimi, S.H. and Ziaeimoghadam, H.R. (013) Efficiency Improvement Method of Ga urbine. Energy and Environmental Engineering, 1, 36-54. [9] Ahmed, S.Y. (013) erformance of the ombined Ga urbine-steam ycle for ower Generation. Mathematical 1
heory and Modeling, 3, 1. [10] Korobityn, M.A. (1998) New and Advanced Energy onverion echnologie. Analyi of ogeneration, ombined and Integrated ycle. Febodruk BV. [11] Lebele-Alawa, B.., Hart, H.I., Ogagi, S.O.. and robert, S.D. (008) Rotor-Blade rofile Influence on a Ga urbine ompreor Effectivene. Applied Energy, 85, 494-505. http://dx.doi.org/10.1016/j.apenergy.007.1.001 [1] Lebele-Alawa, B.. and Jo-Appah, V. (015) hermodynamic erformance Analyi of a Ga urbine in an Equatorial Rain Foret Environment. Journal of ower and Energy Engineering, 3, 11-3. http://dx.doi.org/10.436/jpee.015.3100 [13] Ragland, A. and Stenzel, W. (000) ombined ycle Heat Recovery Optimization. roceeding of 000 International Joint ower Generation onference, Miami Beach, 3-6 July 000, 1781-1787. [14] Armando, A. (013) Optimization of Maputo ower lant. Mater of Science hei KH School of Indutrial Engineering and Management Energy echnology, OKHOLM. [15] Jehar and Aociate. Introduction to HRSG deign. www.hrgdeign.com [16] Kehlhoffer, R. (1997) ombined ycle Ga and Steam urbine ower lant. enn Well ublihing ompany, Oklahoma. [17] Aref,. (01) Development of Framework for hermo-economic Optimization of Simple and ombined Ga urbine ycle. h.d. hei, School of Engineering, ranfield Univerity, Bedfordhire. [18] Service Manual (Ga urbine MS 5001) of 5 MW Unit of Omoku ower Generation Station. GES Oil & Ga, Nuovo ignone, Volume 1; G. Decription, Intruction & Operation. [19] Nag,.K. (011) ower lant Engineering. 3rd Edition, ata McGraw-Hill Education rivate Limited, New Delhi. Nomenclature c peg Specific heat of exhaut ga at contant preure, kj/kg K c p w Specific heat of water, kj/kg K h 1 Enthalpy at team turbine inlet, kj/kg h Enthalpy at team turbine outlet, kj/kg h 1 Enthalpy at team turbine outlet (actual), kj/kg h 3 Enthalpy at condener outlet, kj/kg h 4 Feed water enthalpy, kj/kg h 1 Feed water enthalpy (actual), kj/kg 4 h 5 Enthalpy at economizer exit, kj/kg h 6 Enthalpy at evaporator exit, kj/kg H L Heat lo, MW eg Ma flaw rate of exhaut ga in, kg/ w Ma flow rate of cooling water, kg/ Ma flow rate of team in, kg/ 1 Steam aturation preure, bar ondener preure, bar ompreor ower, MW urbine ower, MW ombined cycle power output, MW g Ga turbine power output, MW NE Steam turbine net power output, MW ump power input (actual), MW Steam turbine power output, MW Q 1 Heat Supplied, MW Q Heat Rejected, MW Q Heat recovered by economizer (economizer capacity), MW ec 13
Q eg Heat rejected by exhaut ga, MW Q eg ec Exhaut ga energy at the economizer, kj/kg Q eg ev Exhaut ga energy at the evaporator, kj/kg Q eg h Exhaut ga energy at the uperheater, kj/kg Q HRSG Heat recovered by HRSG (HRSG capacity), MW Q h Heat recovered by uperheater (uperheater capacity), MW Q ev Heat recovered by evaporator (evaporator capacity),mw a HRSG tack emperature, d Ga turbine exhaut emperature, ondener aturated temperature, x emperature of exhaut ga at pinch point, t in emperature of cooling water into condener, t out emperature of cooling water out of the condener, W Net work output, kj/kg net Greek Symbol Efficiency, % th hermal efficiency % c ompreor ientropic efficiency, % Steam turbine thermal efficiency % g Ga turbine thermal efficiency % ombined cycle overall efficiency, % cond ondener efficiency, % inch point temperature difference, t pp Subcript G Ga At contant preure th hermal i Ientropic in Inlet out Outlet Abbreviation ombined cycle power plant O arbondioxide EG Exhaut ga temperature GE General electric G Gaturbine HMI Human machine interface HRSG Heat recovery team generator IR Intercooled/recuperated kg Kilo gram kw Kilo watt L Low preure compreor MW Mega watt OR Overall preure ratio S Siemen team turbine Steam turbine WBGU German adviory council on global change 14