• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Comparing the thermal power plant performance at variou 2
 

Comparing the thermal power plant performance at variou 2

on

  • 196 views

 

Statistics

Views

Total Views
196
Views on SlideShare
196
Embed Views
0

Actions

Likes
0
Downloads
7
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Adobe PDF

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Comparing the thermal power plant performance at variou 2 Comparing the thermal power plant performance at variou 2 Document Transcript

    • International Journal Mechanical Engineering and InternationalJournal ofof Mechanical Engineering Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July and Technology (IJMET), ISSN 0976 – 6340(Print) (2011), © IAEME ISSN 0976 – 6359(Online) Volume 2 Issue 2, May – July (2011), pp. 111-126 ©IAEME © IAEME, http://www.iaeme.com/ijmet.html IJMET COMPARING THE THERMAL POWER PLANT PERFORMANCE AT VARIOUS OUTPUT LOADS BY ENERGY AUDITING (A STATISTICAL ANALYZING TOOL) 1 Manjinder Bajwa, 2Piyush Gulati 1,2 Asst. Prof., Department of Mechanical Engineering, Lovely Professional University, Jalandhar, Punjab-144402 (India) man_bajwa@yahoo.co.in ABSTRACT In the present scenario of rapidly growing demand of energy in transportation, agriculture, domestic and industrial sectors, the auditing of energy has become essential for over coming the mounting problems of the world wide crisis and environmental degradation. There are two factors contributing to the increase in the energy consumption, one is more than 20% increase in world’s population and another one is worldwide improvement in standard of living of human being. The industrial sector consumes about 50% of total generated energy. Therefore improving energy efficiency is the main focus of Energy Auditing. Experiments are carried out to validate the results, obtained by the Energy Auditing at Panipat Thermal Power Station in Unit 7th which has maximum power generated capacity of about 250MW. The auditing of energy is basically determining the efficiency of Unit 7th of PTPS. Energy Auditing in thermal power plant covers the overall process of data collection and carrying out technical and financial analysis to evolving specific energy management action. Energy Audit identifies the performance of each & every equipment and compares it with the base case. KEYWORDS: Energy Management, Energy Audit, Power Plant, and Energy Conservation. 1.0 INTRODUCTION To meet the growing demand for energy in industries, one of the aims is to identify the technical support in improving their energy performance through comprehensive energy audits, implementation assistance, technology audits, and capacity building. Energy audits help in identifying energy conservation opportunities in all the energy consuming sectors. While these do not provide the final answer to the problem, but do help to identify the existing potential for energy conservation, and induces the organizations/individuals to concentrate their efforts in this area in a focused manner. 111
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME 1.1 Energy Audit: An energy audit is a technique for identifying energy losses, quantifying them, estimating conservation potential, evolving technological options for conservation and evaluating techno economics for the measures suggested. i) Assist industries in reducing their energy consumption. ii) To promote energy-efficient technologies among industry sectors. iii) Disseminate information on energy efficiency through training programs and workshops. iv) To promote transfer of energy-efficient and environmental-sound technologies to the industrial sectors in the context of climate change. 1.2 Energy Audit Technique: The energy audit evaluates the efficiency of all process equipment/systems that use energy. The energy auditor starts at the utility meters, locating all energy sources coming into a facility. The auditor then identifies energy streams for each fuel, quantifies those energy streams into discrete functions, evaluates the efficiency of each of those functions, and identifies energy and cost savings opportunities. The types of Energy Audit are as follows: G. Insulation Audit A. Walk through Audit H. Specific Energy Consumption B. Total System Audit I. Hot Steam Analysis C. Fired Heaters J. Cooling Systems Audit D. Boilers/Steam Generations Plant K. Energy Projects Evaluation E. Steam System Audit F. Electrical System Audit From the above mentioned systems, this research work containing the study of Total System Audit and its implementation methodology. 1.2 Total System Audit: This approach analysis the total system by detailed analysis as the total energy data is entered in a master database file. This contains design data and also the observed data. This approach gives the energy performance of the total system and identifies areas of improvements on energy cost or energy quantity basis. This method requires rigorous data entry and analysis. 2.0 LITERATURE REVIEW Organizational structure of electricity supply industry in India has been evolutionary in nature. To understand this evolution it would be necessary to go over the past history of the electricity supply industry. In the year 1883 the first electric supply undertaking in the country was sponsored by a company, which constructed a small-generated solution in the city of Surat (Gujrat). Energy conservation of the systems has become the topic of research in the recent period. Many researchers investigated and formulated the effects of energy conservation for the efficient energy usage particularly in industrial sector. E.Raask [1969], elaborated about tube failures occurring in the primary super heaters and repeaters and in economizers of coal fired boilers, which are result of erosion, wear caused by impaction of ash particles. Pilat et. Al. [1969], discussed about source test cascade impact or for measuring the size distribution of particles in stacks and ducts and air pollutant emission sources. This impactor is inserted inside the duct or stack to minimize tubing ball losses and water condensation problem. 112
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME Schulz [1974], studied the size distribution of sub-micron particles emitted from a pulverized coal fired power plant and were measure using two types of cascade impactors. Scanning electronic microscope photographs shows particles were spherical with mean size entering and leaving the electrostatic precipitator of 5 and 21/4 micrometers although the slope of curve for each impactor differed. Neal [1980], abbreviated about the conventional automatic control of boiler outlet steam pressure by means of the demand to the pulverized fuel mills has been found to be unstable on some coal fired-boiler turbine units. The frequency response of mills and boiler are obtained from tests in which the mill demand was perturbed with single frequency sinusoids. It is impracticable to measure the fuel output from the mills directly, but this is inferred from oxygen in the flue gas measurement coal/ash properties. Doglin [2001], abbreviated after reviewing the current combustion technologies for the burning pulverized coal with frequent and large fluctuation in coal quality and load demand, a new concept of quasi –constant temperature combustion for pulverized coal is purposed. There are more than fifty researchers whose research in the same field. The main aim of their research is to conserved the energy for future and reduce the energy loss during transformations from one form to other. 3.0 INTRODUCTION TO THERMAL POWER PLANT Thermal Power Station Panipat, a bunching of eight individual units with total installed capacity of 1360 MW is located about 8 KM in the west of Panipat city on Panipat-Hissar National Highway and is surrounded by cultivated green fields. In addition, 640 acres of saline wasteland is earmarked for disposal of ash. The plant is equipped with a huge residential colony to ensure availability of staff and officers round the clock. Unit No. 1 was commissioned on 1st November, 1979 Haryana day by the then President of India Shri Neelam Sanjeeva Reddy with subsequent commissioning of Units. Table 1 shows the overall means the total performance of 8 Units year by year. Table 1. Performance of Panipat Thermal Power Station Year Generation (MW) 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 2008-09 2009-10 2868.835 2656.030 2856.040 2727.994 4123.94 4992.264 5949.260 5756.5968 8135.6993 9908.1265 Plant Load Auxiliary Factor (%) Cons. (%) 50.38 46.65 50.02 47.91 61.86 66.26 78.75 71.14 68.53 83.17 11.80 11.75 11.41 11.43 10.67 10.14 10.08 10.74 9.79 9.48 114 Oil Coal Consumption Consumption (ml/kwh) (kg/kwh) 13.72 0.828 14.22 0.824 6.89 0.784 6.23 0.791 3.04 0.769 3.49 0.745 3.21 0.744 3.90 0.762 3.56 0.714 1.39 0.699
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME 3.1 Basic Information regarding Power Generation at Thermal Power Plant Station Thermal Power Plant burns fuels and uses the resultant heat to convert water in the steam, which drive the turbo generator. The fuel may be ‘fossil’ (Coal, Oil or Natural Gas) or it may be fissionable (uranium). Whichever fuel is used the object is same to convert heat into mechanical energy into electricity by rotating a magnet inside a set of windings. Conventional power plants work on RANKINE CYCLE. The cycle may be split into distinct operations: Water is admitted to the boiler raised to boiling temperature and then superheated. The superheated steam is fed to a steam turbine where it does work on the blades as it expends. The expended steam is rejected o the condenser and the resultant condensate is fed back to the boiler via feed heaters. The turbine drives a generator, which is turn supplies electricity to the bus bars. 3.2 Problem Formulation In PTPS, Unit No. 7 having an output capacity of 250 MW is considered for energy Auditing Process. Energy Audit has been done for evaluating the performance of main Unit and also the performance of sub units like Boiler, Turbine and generator, Condenser & Heater are calculated, and compared their performance at different output loads. The main problems, which are highlighted in PTPS Unit No. 7 are: Energy efficiency has to be improved to survive in Global Market. To extend the life of units by 15 to 20 years To restore original rated capacity of the units. To improve Plant availability/ load factor. To enhance operational efficiency and safety. To remove ash pollution and to meet up environmental standards. 3.3 History of Unit 7th The unit was commissioned on coal firing on 28-09-2004 & dedicated on commercial run w.e.f. 29-12-2004. The some of the main achievements of Unit 7th are lined below: i. Unit-7th generated 1977.9204 MU (PLF 90.32%) during 2006-2007 which is the highest generation from this unit after its commissioning. ii. Monthly highest generation of Unit-7th remained 189.034 MU (PLF 101.63%) during Jan.-2007, which is the highest during a month since commissioning of this unit. iii. %age Aux. Consumption of Unit-7th remained 8.44% during this FY. Earlier lowest Aux. Consumption was 9.76% during 2004-2005 iv. Specific coal consumption of Unit-7th remained 0.628 Kg/Kwh during this FY, which is the lowest since its commissioning. 115
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME v. vi. The Heat Rate of Unit-7th remained 2507 Kcal/kwh, which is the lowest since commissioning of the unit. Unit-7th (250 MW) remained in continuous operation from 11-01-2007/2130 Hrs to 08-03-2007/1555 Hrs (55 Days 18 Hrs 25 Mts), which is the highest continuous running since commissioning the Unit. 3.4 Data Collection The data for the auditing purpose is collected from the experimental work. The experimental work is done at different output loads [250 MW, 232 MW, 210 MW respectively] and summarized in tables below. The Table 2, 3 and 4 shows the data of thermal power plant at different loads of 250 MW, 232 MW, 210 MW respectively. Sr. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Table No.2 Data for Thermal Power Plant at Output load 250 MW Pr. Tem. Flow Enthalpy Description Condition 0 bar C T/Hr KJ/Kg Superheat Steam Inlet HPT 150 540 782 3414.6 Steam Steam Outlet HPT Superheat and 38 340 710 2574.6 Steam Inlet Re-heater Steam Outlet ReSuperheat 38 540 710 3414.6 heater and inlet IPT Steam Steam Outlet IPT Superheat 8 340 630 2574.6 and inlet LPT Steam 6th Extraction HPT Superheat 38 340 70 2574.6 and inlet HPH6 Steam HPH6 Outlet and Water 24 210 70 2028.6 Inlet HPH5 5th Extraction IPT Superheat 18 430 46 2952.6 and Inlet HPH5 Steam HPH5 Outlet and Water 7 200 125 1986.6 Inlet Dearator 3rd Extraction IPT Superheat 9 311 26 2452.8 and Inlet LPH3 Steam Drip Outlet LPH3 Water 123 1663.2 and Inlet LPH2 2nd Extraction LPT Superheat 1.6 213 22 2041.2 and Inlet LPH2 Steam Drip Outlet LPH2 Water -0.6 125 1671.6 and Inlet LPH1 1st Extration LPT Superheat -1.8 98 28 1558.2 Inlet LPH1 Steam Drip Outlet LPH1 and Inlet to HotWater 50 1356.6 well Exhaust Steam Superheat 0.09 45 530 1335.6 Outlet LPT Steam Condenser Outlet & Water 0.1 36 530 1297.8 Inlet Hot-well Condensed Steam Inlet to LPH1 Water 11.8 116 50 652 1356.6 Energy MW 741.73 507.77 673.43 450.56 50.06 39.45 37.73 68.98 17.71 12.47 12.12 196.63 191.06 245.69
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Condensate Outlet LPH1 and Inlet LPH2 Condensate Outlet LPH2 and Inlet LPH3 Condensate Outlet LPH3 and Inlet Dearator BFP Inlet Condensate Inlet HPH5 Condensate Outlet HPH5 and Inlet HPH6 Condensate Outlet HPH6 and Inlet Economizer Feed Water Inlet Drum Steam Inlet LTSH Steam Inlet Platen SH Steam Inlet Final Super Heater Flue Gas Inlet Reheater Flue Gas Inlet Final Super Heater Flue Gas Inlet Platen Super-heater Flue Gas Inlet LTSH Flue Gas Inlet Economizer Flue Gas Inlet APH Flue Gas To Stack SA Inlet APH SA Inlet Boiler PA Inlet APH PA Inlet Boiler Coal Supply to Boiler Cold Water Inlet to Condenser Hot Water Outlet From Condenser Water 11.8 72 652 Water 11.26 92 1449 262.43 652 1533 120 18.4 163 786 Water 188 167 786 Water 187 202 1848 403.48 435.58 472.26 2196.6 2637.6 479.59 575.88 1146.6 250.34 3406.2 743.69 652 Water 298.94 399.81 2163 9.8 1650.6 1831.2 1995 Water 277.64 786 Water 183 242 786 Water 174 250 786 Steam 160 355 786 Steam 786 Steam 145 538 786 Flue Gas -22 740 880 Flue Gas -19.2 650 880 Flue Gas -0.1 1120 880 Flue Gas -1.1 916 880 Flue Gas -0.7 456 880 Flue Gas Flue Gas Air Air Air Air -1.8 0.15 250 250 800 700 296 149 295 290 36 278 880 880 880 900 150 150 4254.6 1040.01 120 Water 7 30 45000 Water 6 38 947.61 5850.6 1430.15 4993.8 1220.71 3061.8 2389.8 1772.4 2385.6 2364.6 1297.8 2314.2 748.44 584.17 433.25 583.15 591.15 54.08 96.43 1146.6 1272.6 38.22 15907.5 0 1306.2 Coal 3876.6 16327.5 0 45000 117
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME Table 3 Data of Thermal Power Plant at output load 232 MW Sr. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 Description Condition Pr. bar Tem. 0 C Flow T/Hr Enthalpy KJ/Kg Energy MW Steam Inlet HPT Superheat Steam 141 534 735 3389.4 692.01 Superheat Steam 35 340 675 2574.6 482.74 33 533 675 3385.2 634.73 6 350 600 2616.6 436.11 34 330 60 2532.6 42.22 Water 20 205 60 2007.6 33.47 Superheat Steam 15 420 40 2910.6 32.34 Water 6.5 171 100 1864.8 51.8 Superheat Steam 8 303 20 2419.2 13.45 1.4 218 17 2062.2 9.73 Steam Outlet HPT and Inlet Re-heater Steam Outlet Reheater and inlet IPT Steam Outlet IPT and inlet LPT 6th Extraction HPT and inlet HPH6 HPH6 Outlet and Inlet HPH5 5th Extraction IPT and Inlet HPH5 HPH5 Outlet and Inlet Dearator 3rd Extraction IPT and Inlet LPH3 Drip Outlet LPH3 and Inlet LPH2 2nd Extraction LPT and Inlet LPH2 Drip Outlet LPH2 and Inlet LPH1 1st Extraction LPT Inlet LPH1 Drip Outlet LPH1 and Inlet to Hot-well Exhaust Steam Outlet LPT Condenser Outlet & Inlet Hot-well Condensed Steam Inlet to LPH1 Condensate Outlet LPH1 and Inlet LPH2 Condensate Outlet LPH2 and Inlet LPH3 Condensate Outlet LPH3 and Inlet Dearator BFP Inlet Condensate Inlet HPH5 Condensate Outlet HPH5and Inlet HPH6 Condensate Outlet HPH6 and Inlet Economizer Feed Water Inlet Drum Steam Inlet LTSH Steam Inlet Platen SH Superheat Steam Superheat Steam Superheat Steam Water Superheat Steam Water Superheat Steam 120 -1.5 Water 97 1650.6 23 47 1554 9.93 1344 Superheat Steam 0.08 45 505 1335.6 187.36 Water 0.08 40 505 1314.6 184.41 Water 11 45 600 1335.6 222.6 Water 10.5 71 600 1444.8 240.8 Water 10 89 600 1520.4 253.41 Water 8.6 117 600 1638 273.01 Water 16 160 718 1818.6 362.7 Water 172 161 718 1822.8 363.54 Water 171 196 718 1969.8 392.87 Water 168 238 718 2146.2 428.04 Water 160 246 718 2179.8 434.74 Steam Steam 156 351 718 718 2620.8 522.69 118
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Steam Inlet Final Super Heater Flue Gas Inlet Reheater Flue Gas Inlet Final Super Heater Flue Gas Inlet Platen Super-heater Flue Gas Inlet LTSH Flue Gas Inlet Economizer Flue Gas Inlet APH Flue Gas To Stack SA Inlet APH SA Inlet Boiler PA Inlet APH PA Inlet Boiler Coal Supply to Boiler Cold Water Inlet to Condenser Hot Water Outlet From Condenser Steam 141 532 718 3381 674.3 Flue Gas -10 635 800 3813.6 847.46 Flue Gas -7 620 800 3750.6 833.46 Flue Gas -0.08 950 800 5136.6 1141.46 Flue Gas -0.4 861 800 4762.8 1058.39 Flue Gas -0.65 433 800 2965.2 658.93 Flue Gas Flue Gas Air Air Air Air Coal -0.8 0.143 240 240 615 615 294 147 292 272 36.5 292 800 800 800 850 142 142 114 2381.4 1764 2373 2289 1299.9 2373 529.19 392 527.33 540.46 51.27 93.60 Water 6 30 40000 1272.6 14139.99 Water 5 37 40000 1302 14466.67 Table 4 Data of Thermal Power Plant at load 210 MW Sr. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Description Condition Steam Inlet HPT Superheat Steam Steam Outlet HPT and Inlet Re-heater Steam Outlet Reheater and inlet IPT Steam Outlet IPT and inlet LPT 6th Extraction HPT and inlet HPH6 HPH6 Outlet and Inlet HPH5 5th Extraction IPT and Inlet HPH5 HPH5 Outlet and Inlet Dearator 3rd Extraction IPT and Inlet LPH3 Drip Outlet LPH3 and Inlet LPH2 2nd Extraction LPT and Inlet LPH2 Drip Outlet LPH2 and Inlet LPH1 1st Extraction LPT Inlet LPH1 Drip Outlet LPH1 and Inlet to Hot-well Superheat Steam Superheat Steam Superheat Steam Superheat Steam Water Superheat Steam Water Superheat Steam Pr. bar 135 Tem. 0 C 530 Flow T/Hr 685 Enthalpy KJ/Kg 3372.6 Energy MW 641.73 33 338 635 2566.2 452.65 32 530 635 3372.6 594.89 5 338 565 2566.2 402.75 32 328 48 2524.2 33.66 18 200 48 1986.6 26.49 12 412 26 2877.0 20.78 6 156 80 1801.8 40.04 7 295 16 2385.6 10.60 0.0 0.00 2007.6 8.37 1629.6 0.00 1545.6 7.73 1339.8 0.00 Water Superheat Steam 1.2 15 115 Water Superheat Steam 205 -1.2 95 46 Water 119 18
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 Exhaust Steam Outlet LPT Condenser Outlet & Inlet Hot-well Condensed Steam Inlet to LPH1 Condensate Outlet LPH1 and Inlet LPH2 Condensate Outlet LPH2 and Inlet LPH3 Condensate Outlet LPH3 and Inlet Dearator BFP Inlet Condensate Inlet HPH5 Condensate Outlet HPH5and Inlet HPH6 Condensate Outlet HPH6 and Inlet Economizer Feed Water Inlet Drum Steam Inlet LTSH Steam Inlet Platen SH Steam Inlet Final Super Heater Flue Gas Inlet Reheater Flue Gas Inlet Final Super Heater Flue Gas Inlet Platen Super-heater Flue Gas Inlet LTSH Flue Gas Inlet Economizer Flue Gas Inlet APH Flue Gas To Stack SA Inlet APH SA Inlet Boiler PA Inlet APH PA Inlet Boiler Coal Supply to Boiler Cold Water Inlet to Condenser Hot Water Outlet From Condenser Superheat Steam 475 1331.4 175.67 0.07 38 475 1306.2 172.35 10.5 43 550 1327.2 202.77 70 550 1440.6 220.09 9.5 87 550 1512 231.00 8.2 115 550 1629.6 248.97 15 166 158 159 650 650 1810.2 1814.4 326.84 327.60 165 190 650 1944.6 351.11 160 Water 44 10.5 Water 0.07 234 650 2129.4 384.48 154 244 650 2171.4 392.06 150 345 138 527 650 650 650 2595.6 0 3360 468.65 0.00 606.67 -8 610 760 3708.6 782.93 -6 600 760 3666.6 774.06 -0.06 900 760 4926.6 1040.06 -0.2 -0.58 840 423 760 760 4674.6 2923.2 986.86 617.12 -0.6 0.13 230 230 550 550 292 145 292 65 36 277 5 30 760 760 760 790 130 130 110 35000 2373 1755.6 2373 1419.6 1297.8 2310 0 1272.6 500.97 370.63 500.97 311.52 46.87 83.42 0.00 12372.50 4 36 35000 1297.8 12617.50 Water Water Water Water Water Water Water Water Steam Steam Steam Flue Gas Flue Gas Flue Gas Flue Gas Flue Gas Flue Gas Flue Gas Air Air Air Air Coal Water Water Note: In Table 2,3 & 4, the value of energy is calculated from the formula given as: Energy = Flow (Kg/Sec.) * Enthalpy (KJ/Kg)/1000 4.0 DATA ANALYSIS In this step, the data, which is collected from Power Plant Unit No.7 & at different output load, is analyzed. Firstly from the data of Thermal Power Plant 120
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME running at the load of 250MW or full output load given in Table 2 is considered for the analysis purpose. The data analysis work is as below: Step 1: Boiler Section • Inlet in Boiler (i) Coal Inlet [40] = 120T/hr = 120 x 1000/3600 =33.33 Kg./Sec. Calorific Value of Coal = 4860 K Cal/Kg Therefore, Energy = 4860 x 33.33 x 4.2/1000 = 680.33 MW (ii) Reheated Steam Inlet Energy [2] = 507.77 MW (iii)Inlet from Economizer Steam Energy [24] = 472.26 MW Total Inlet = (i) + (ii) + (iii) = 680.33 + 507.77 +472.26 = 1660.36 MW • Outlet from Boiler (iv) Steam Inlet HPT Energy [1] = 741.73 MW (v) Steam Outlet From Reheated Energy [3] = 673.44 MW (vi)Flue Gases = Generally not taken in considration Total Outlet = (iv) + (v) + (vi) = 741.73 + 673.44 + 0 = 1415.17 MW Loss in Boiler = Inlet – Outlet = 1660.36 – 1415.17 = 245.19 MW Efficiency of Boiler = 1415.17 x 100/ 1660.36 = 85.23 % Step2: Section Turbine & Generator Section (i) HPT Inlet [1] = 741.73 MW (ii) HPT Outlet [2] + Extraction HPT [5] = 507.77 + 50.06 = 557.83 MW Net Energy at HPT = (i) - (ii) = 741.73 – 557.83 = 183.9 MW (iii) IPT Inlet [3] = 673.44 MW (iv) IPT Outlet [4] + Extraction IPT [7] = 450.55+37.73 = 488.28 MW Net Energy at IPT = (iii)- (iv) = 673.44 – 488.28 = 14.84 MW (v) LPT Inlet [4] = 450.56 MW (vi) LPT Outlet [9] + Extraction LPT [11] + Inlet LPH [13] =17.71+12.47 +12.12 = 42.3 MW Net Energy at LPT = (v) – (vi) = 450.56 – 42.3 = 408.26 MW Net Input at Turbine (HPT, IPT & LPT) = 183.9 + 14.84 + 408.26 = 607 MW Efficiency of Turbo Generator = 250 x 100/ 607 = 41.19 % Step 3: Section Condenser: Condenser Efficiency = Actual Cooling Water Temp rise Max Possible Temp. Rise = Water Outlet Temp. [42]- Water temp. at Inlet to condenser [41] * 100 Exhaust Steam Temp. [15] – Water temp. at Inlet to condenser [41] = 53.33 % = (38 – 30) x100 45 – 30 Step 4: Section Heaters (LP & HP) LPH1 Effectiveness = T [18] – T [17] T [13] – T [17] LPH2 Effectiveness = T [19] – T [18] T [11] – T [18] LPH3 Effectiveness = T [20] – T [19] T [9] – T [19] HPH5 Effectiveness = T [23] – T [22] T [7] – T [22] 121 = 72 – 50 98-50 = 92 – 72 213-72 = 120-92 311-92 = 202-167 430-167 = 0.46 = 0.14 = 0.13 = 0.13
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME HPH6 Effectiveness Overall Unit Efficiency = T [24] – T [23] = 242-202 = 0.29 T [05] – T [23] 340-202 = Output of Station x 100 Input of Station = Energy sent out (KW) . Fuel burnt (Kg) x Calorific value of fuel (K Cal/kg) = 250 x 100 = 36.74% 680.33 Similarly, the data of plant running at output load of 232 MW & at 210 MW is analyzed and the results are shown in Table 5. Table 5 Analyze data for the plant running at 232 MW & 210 MW Description Inlet in Boiler Outlet from Boiler Loss in Boiler Efficiency of Boiler Section Turbine & Net Energy at HPT Generator Section Net Energy at IPT Net Energy at LPT Net Input at Turbine Efficiency of Turbo Generator Section Condenser Condenser Efficiency Section Heaters LPH1 Effectiveness (LP & HP) LPH2 Effectiveness LPH3 Effectiveness HPH5 Effectiveness HPH6 Effectiveness Overall station efficiency Boiler Section At 232 MW 1557.23 MW 1326.74 MW 230.49 MW 85.20 % 167.05 MW 166.28 MW 403.08 MW 736.41 MW 31.50 % 46.67 % 0.50 0.12 0.13 0.13 0.31 35.89% At 210 MW 1460.72 MW 1236.62 MW 224.1 MW 84.66 % 155.42 MW 171.36 MW 376.03 MW 702.81 MW 29.88 % 42.86 % 0.51 0.12 0.13 0.12 0.33 33.67% Now, from the data calculated for analysis purpose above is used for finding the problems and their recommendations. The above data is summarized in Table 6. Table 6 Analyzed data for different parameters of the plant running at various load S. No. 1 2 3 4 5 6 7 8 9 10 Description Boiler Efficiency Turbine & Generator Efficiency Condenser Efficiency Heater LPH1 Effectiveness Heater LPH2 Effectiveness Heater LPH3 Effectiveness Heater HPH5 Effectiveness Heater HPH6 Effectiveness Overall Plant Efficiency Coal Consumption 250MW 85.23% 41.19% 53.33% 0.46 0.14 0.13 0.13 0.29 36.74% 120 T/Hr 232MW 85.20% 31.51% 46.67% 0.50 0.12 0.13 0.13 0.31 35.89% 114 T/Hr 220 MW 84.66% 29.88% 42.86% 0.51 0.12 0.13 0.12 0.33 33.67% 110 T/Hr On the data in Table 6, parato diagram is made, which is more helpful to find the exact status of the plant. Figure 1 shows the Efficiencies comparison between the 122
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME various plant output levels in term of Boiler Efficiency, Turbine & Generator Efficiency & Condenser Efficiency. Figure 2 & 3 shows the Effectiveness value for the heaters at various output level & finally the Figure 4 shows the comparison between overall plant efficiency at various output level. Various efficiencies comparision for plant running at various output values 90.00% Efficiency Value 80.00% 70.00% 60.00% 50.00% 40.00% 30.00% 20.00% 10.00% 0.00% Boiler Efficiency Turbine & Generator Efficiency Condenser Efficiency Efficiency Figure 1 Parato Analysis for various efficiencies for plant running at various output values Heater Effectiveness values for various output values 0.6 0.4 0.3 0.2 0.1 Series1 Heater LPH3 Heater LPH2 0 Heater LPH1 Effrctiveness Value 0.5 Heaters Detail Figure 2 Parato Analysis for Heaters Effectiveness Values 123 Series2 Series3
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME Heater Effectiveness value for Various Output Values of the Plant 0.35 0.3 Effectiveness Value 0.25 0.2 0.15 0.1 0.05 0 Heater HPH5 Heater HPH6 Heaters Detail Figure 3 Parato Analysis for Heaters Effectiveness Values Plant Efficiency in (%age) Overall Plant Efficiency at Various Output Level 37.00% 36.50% 36.00% 35.50% 35.00% 34.50% 34.00% 33.50% 33.00% 32.50% 32.00% At 250MW At 232 MW At210 MW Plant Output Detai l Figure 4 Parato Analysis for Overall Plant Efficiency 5.0 RESULTS & RECOMMENDATIONS From the analysis part of this work, it is concluded that the overall plant efficiency varies with the variation or small change in the output loads. From the experimental work done in above steps shows that as the output load is lower the 124
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME efficiency of total unit is low. Output Load of the plant always depends upon the requirements for consumption of energy. As the energy consumption decreases, Plant has to be starting to run at lower load and the overall performance is also lower, because energy cannot be stored. On the other hand if the Plant or Unit can run at Full Output Load or 250 MW load the performance is higher. Some of the recommendations based on this research work are made for increasing the performance of the plant is shown in Table 7. Table 7 Recommendation for increasing Plant Efficiency Description Recommendation Boiler Section Condenser Overall Plant Efficiency Boiler Efficiency can increased upto 90 % to 95 % Low condenser vacuum due to:(a) Air ingress in the condenser. (b) Dirty tubes. (c) Inadequate flows of Condensate Water in condenser. Overall efficiency of plant can be increased 1. By increasing the oxygen content of the coal, result in reduced level of heating valve 2. Boiler efficiency is mainly attributed to dry flue gas, wet gas & sensible heat loss so that by reducing the flue gas exhaust temperature. 3. Periodic maintenance of boiler like: (a) Periodical cleaning of boiler. (b) Proper water treatment programmes and blow down control. (c) Excess air control. (d) Percentage loading of boiler. (e) Steam generation pr. and temperature. (f) Boiler insulation (g) Quality of fuel. (i) Cooling Water flow must be checked for correct quantity. (ii) Condenser tubes must be cleaned regularly. (iii) Vacuum drop must be cleaned regularly. CW pumps impeller must be checked for erosion. (iv) Air ingress must be arrested. (v) Improvement in quality of cooling water and close cycle. By using wash-coal, which will save the energy from waste with ash. 6.0 REFERENCES & BIBLIOGRAPHY 1. Raask, E Lo, K.L. & Song E, Z. M.(1969), “Tube Failures Occurring in the primary super heaters and reheaters and in the economizers of coal fired boilers”, Energy Conservation in Coal fired boilers , Vol.12, 1969, Page No. 185. 2. Rajan G.G. (2001), “Optimizing Energy efficiency in industries by Energy Loss Control-models”, Chapter-14, Page No. 276. 125
    • International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print), ISSN 0976 – 6359(Online) Volume 2, Issue 2, May- July (2011), © IAEME 3. Pilat, J., Micheel P. A. (1969) “Source test Cascade impactor for measuring the size ducts in boilers”, Energy Conservation in Coal fired boilers, Vol. 10, Page No.410-418. 4. Schulz, E., Worell, E. & Blok, K. (1974) “Size distribution of submission particulars emitted from Pulverized coal fired plant” Energy Conservation in Coal Fired boilers, Vol. 10, Page No.74-80. 5. Neal, P.W.Lo, K.L. (1980) “Conventional automatic control of boiler outlet steam pressure” Energy Conservation in Coal fired boilers, Vol. 16, Page No. 91-98. 6. Dognlin, Chen James, D & Varies B.de (2001), “Review of current combustion, technologies for burning pulverized coal”, Energy conservation in coal fired boilers Vol.48, Page No. 121-131. 7. Bergander, Mark J. Porter, R.W. (2003), “ Most troublesome component of electric power generation plant”, Energy conservation in coal fired boilers, Vol. 32, Page No. 142-149. 8. Hatt, Roderick, M. & Lewis, W (2003), “Coal ash deposits in coal fired boilers” Energy conservation of coal fired boilers, Vol. 14, Page No. 181-189. 9. Central Electricity Generating Board, “Modern Power Station Practice (Operation & Efficiency),” Pergamon Press Oxford, New York. 2nd Edition, Volume-7. 10. P.K.Nag “Power Plant Engineering” Tata McGraw-Hill Publishing Company Limited New Delhi. 2nd Edition. 126