正反平衡计算煤耗结果非一致性的原因分析新疆华电昌吉热电二期有限责任公司 成志刚[摘 要]在利用标准DL/T904-2004中有关正反平衡煤耗计算式计算煤耗时，发现两者存在较大的差距，对此差距进行了原因分析，并提出缩小差距的措施。
[关键词]正平衡、反平衡、流量、煤耗、标准正反平衡计算煤耗的由来火力发电厂既是能源转换企业，又是耗能大户，因此技术经济指标对火力发电厂的生产、经营和管理至关重要。
火电厂技术经济指标计算不仅反映电力企业的生产能力、管理水平，还可以指导火电厂电力生产、管理、经营等各方面的工作。
煤耗是火力发电厂的一项重要经济指标和生产技术指标。
它综合反映了一个电厂的生产管理和机组性能水平。
同时煤耗指标也是反映火电企业能耗水平的唯一指标，是国家节能调度的依据和行业电力节能监管的主要指标。
为加强火电厂发供电煤耗的科学管理，使煤耗更加准确，进一步降低发供电煤耗，原能源部在1991年颁布《火力发电厂节约能源规定(试行)》（能源节能〔1991〕98号），98号文第12条要求：火电厂的供电煤耗应按正平衡法计算，并以此数据上报及考核。
依据原能源部98号文的要求，电力部在1993年下发了《火力发电厂按入炉煤量正平衡计算发供电煤耗的方法(试行)》(电安生〔1993〕457号)的通知，457号文第1-2条规定“火电厂发供电煤耗统一以入炉煤计量煤量和人炉煤机械化采样分析的低位发热量按正平衡计算，并以此数据上报。
457号文分门别类的详细的规定了正平衡计算煤耗的方法：纯凝汽式机组按入炉煤量正平衡计算发供电煤耗的方法；发电厂按入炉煤量正平衡计算发供电煤耗的方法；供热式机组按入炉煤量正平衡计算供热与发供电煤耗的方法；热电厂按入炉煤量正平衡计算供热与发供电煤耗的方法。
国家发改委在2004年12月14日首次以“标准”的高度发布了DL/T904-2004《火力发电厂技术经济指标计算方法》,该标准最大的一个贡献是首次以“行业标准”的形式统一了火力发电指标的计算方法，具有“里程碑”意义。
可以说，在此之前火力发电指标的计算处于一种无序的状态，随意性较大。
该标准9.4条款：发电、供热煤耗中提供了正、反平衡法计算式。
基于建立健全以质量为中心、以标准为依据、以计量为手段的“三位一体”节能技术监督体系的需要，以对影响电网和发电设备经济运行的重要性能参数和指标进行监督、检查、评价及调整。
使能源的消耗率达到最佳水平。
国家发改委在2007年7月20日发布了DL/T1052-2007《节能技术监督导则》,该导则第6.2.2.3条款明确要求：发电企业应按照实际入炉煤量和入炉煤机械取样分析的低位发热量正平衡计算发、供电煤耗率。
当以入厂煤和煤场盘煤计算的煤耗率和以入炉煤计算的煤耗率偏差达到1.0%时，应及时查找原因。
发电企业的煤耗率应定期采用反平衡法校核。
该导则不但要求发电企业用正平衡计算发、供电煤耗，而且要求发电企业定期用反平衡法进行校核发、供电煤耗。
只所以有这样的要求，主要就是通过校核对比能发现问题，进而解决问题。
由于采用反平衡计算煤耗的方法复杂、可变参数多，涉及的参数、化验数据、实测数据多，而且不易测准，伸缩性大，有一定的先天不足。
反之，采用正平衡计算煤耗的方法较为简单、可变参数少，涉及的参数、化验数据、实测数据相比反平衡要少的多，而且多数易于测准，伸缩性小，但是并不意味着正平衡就不存在不足,主要是因为入炉煤计量和采制化不完善和不准确。
1基本概念正平衡和反平衡都属于热力系热平衡的研究，是指热力系输入与输出热量之间的平衡。
输出热量包括有效利用热量和生产中的各项热损失，而输入热量主要来源于燃料燃烧放出的热量，分析燃料的热量有多少被有效的利用，有多少变为损失,然后根据情况提高热源的经济性。
根据锅炉效率和锅炉所生产的蒸汽含热量反算出的供电煤耗率，称之为反平衡供电煤耗。
根据入炉煤、油计量装置实测得的发电所消耗的原煤量、燃油量，并按其平均热值计算出耗用的标准煤量，来计算的供电煤耗，称之为正平衡供电煤耗。
2问题的产生笔者按照上述标准的要求和方法，抽取了某年3个月的数据，分别命名为a月、b月和c 月，利用excel的强大运算功能在excel中进行了计算。
为了更加清楚和直观的说明问题，将在excel表格中计算形成的正反平衡发供电煤耗结果列表如下（a月正反平衡发供电煤耗对比表、b月正反平衡发供电煤耗对比表、c月正反平衡发供电煤耗对比表）。
笔者所在公司的机组为两台CC125-9.5/1.3/0.259型双抽汽凝汽式高压供热机组，编号分别为#3和#4。
从表中统计数据可以看出来，正反平衡发供电煤耗的计算结果并不一致，这从理论上讲是个悖论，产生这样的结局正是：标准为什么要求用反平衡进行校核的根源。
就是通过校核对比来验证计量体系的有效性及生产管理水平。
a月正反平衡发供电煤耗对比表日期发电煤耗[g/(kW·h)] 供电煤耗[g/(kW·h)] 正平衡 反平衡 差值 正平衡 反平衡 差值#3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计1 238.43 269.90256.08 202.21 241.12225.3436.22 28.77 30.74 251.50285.10270.32213.30254.71237.8738.21 30.39 32.452 256.36 288.03275.59 218.72 270.19248.9937.65 17.84 26.60 269.56303.99290.35229.98285.16262.3339.59 18.83 28.023 254.23 282.30271.91 223.68 276.23254.7130.54 6.07 17.20 267.62298.01286.66235.47291.60268.5332.15 6.41 18.134 289.03 313.39304.12 230.89 270.38255.0658.15 43.01 49.06 304.75330.48320.68243.44285.13268.9561.31 45.36 51.735 287.90 309.27300.04 232.53 260.23250.1655.37 49.04 49.88 303.65325.66316.19245.26274.02263.6258.39 51.64 52.576 291.45 321.30309.17 221.07 261.27245.4870.38 60.03 63.69 306.66338.40325.48232.61275.17258.4274.05 63.23 67.057 305.59 325.87316.91 234.18 258.90250.4171.41 66.97 66.50 322.46343.18334.06247.10272.65263.9675.36 70.53 70.108 330.74 348.64340.61 239.24 257.64251.9091.50 91.00 88.71 348.90366.89358.85252.38271.12265.3996.52 95.76 93.469 308.60 326.26318.50 236.46 257.11250.5072.13 69.15 68.00 325.44343.18335.42249.37270.44263.8176.07 72.74 71.6110 307.12 322.10315.34 240.89 255.54251.6366.23 66.56 63.72 324.10338.77332.18254.21268.76265.0669.89 70.00 67.1211 297.40 314.49306.75 236.08 251.94247.4561.32 62.55 59.29 313.79330.26322.85249.09264.57260.4464.70 65.69 62.4112 297.43 314.00306.44 237.84 253.81249.1659.60 60.19 57.27 313.85330.10322.71250.97266.82262.4062.89 63.28 60.3113 271.71 287.28280.10 238.08 256.52250.5933.62 30.76 29.51 286.68301.75294.84251.20269.44263.7835.48 32.31 31.0614 273.46 273.27273.09 268.13 259.14266.78 5.33 14.13 6.31 290.18287.58288.53284.52272.71281.87 5.66 14.87 6.6615 264.98 264.28264.36 270.17 261.84268.77-5.19 2.44 -4.41 281.20278.00279.23286.71275.43283.88-5.51 2.57 -4.6516 289.32 288.23288.41 266.98 258.49265.5922.34 29.74 22.82 306.94303.11304.53283.23271.83280.4423.70 31.28 24.0917 292.65 294.67293.40 265.52 259.04265.0927.13 35.63 28.31 310.74309.85309.93281.93272.39280.0228.81 37.46 29.9118 323.77 297.31313.08 362.21 257.90310.32-38.4439.41 2.76 350.89312.73333.90392.55271.28330.96-41.6641.45 2.9419 323.25 297.48312.60 363.39 262.03313.26-40.1435.45 -0.67 350.41313.07333.52393.92275.76334.23-43.5237.31 -0.7120 349.77 321.35337.83 365.04 262.20313.24-15.2859.15 24.59 379.40337.85360.29395.97275.66334.07-16.5762.19 26.2221 356.77 328.26345.52 364.35 260.88313.68-7.58 67.37 31.84 387.39345.12368.78395.62274.29334.79-8.24 70.84 33.9922 332.72 309.84323.94 362.60 263.18313.88-29.8846.66 10.06 360.86326.01345.69393.26276.91334.96-32.4149.10 10.7423 348.21 321.39338.16 373.32 262.19317.51-25.1159.20 20.65 378.75338.45361.44406.06276.11339.36-27.3162.34 22.0824 300.49 283.20295.11 372.68 265.84320.28-72.2017.36 -25.17326.55298.53315.53405.02280.23342.45-78.4618.30 -26.9225 298.86 276.74293.24 374.35 254.20319.22-75.4922.54 -25.98325.08291.37313.81407.19267.64341.61-82.1223.73 -27.80- 3 -26 306.32 302.40304.67 314.31 321.17321.81-7.99 -18.77 -17.14328.99321.31325.44337.57341.25343.75-8.58 -19.94 -18.3127 303.27 299.97301.62 317.37 315.79320.60-14.10-15.82 -18.97325.92319.26322.53341.07336.10342.82-15.15-16.84 -20.2928 296.51 294.64295.91 313.50 320.53320.92-16.99-25.88 -25.02318.71313.54316.47336.97341.09343.23-18.26-27.54 -26.7529 314.22 313.60314.62 308.58 322.77319.73 5.63 -9.17 -5.11 337.41334.30336.60331.36344.07342.07 6.05 -9.77 -5.4730 298.85 301.13301.17 307.86 332.94324.30-9.01 -31.80 -23.12320.77320.96322.14330.44354.86346.88-9.67 -33.90 -24.7331 292.07 306.49300.70 366.41 413.79394.48-74.34-107.30-93.78313.57328.60322.61393.38443.63423.22-79.81-115.03 -100.61 合计 308.23 305.92306.60 286.94 272.44282.7021.29 33.47 23.91 328.82322.67325.13306.10287.37299.7822.71 35.31 25.35b月正反平衡发供电煤耗对比表日期发电煤耗[g/(kW·h)] 供电煤耗[g/(kW·h)] 正平衡 反平衡 差值 正平衡 反平衡 差值#3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计1 290.81 271.36281.96 287.14 230.97259.38 3.67 40.39 22.58 314.39 286.01301.00310.42243.44280.02 3.97 42.58 20.972 297.11 278.35288.96 331.87 263.69298.52-34.7614.66 -9.56 321.02 293.66308.56358.58278.19322.60-37.5615.47 -14.043 303.32 286.41296.31 332.27 262.38298.03-28.9524.03 -1.72 327.70 301.61316.11358.98276.30321.87-31.2825.30 -5.764 296.17 272.41286.89 344.02 254.80299.66-47.8517.61 -12.77321.00 286.62306.35372.86268.10323.81-51.8618.53 -17.465 313.60 277.64303.50 364.55 231.38298.96-50.9546.26 4.54 341.10 291.04324.11396.51242.54322.92-55.4248.50 1.196 308.23 266.59301.14 385.82 219.22304.73-77.5947.37 -3.59 336.85 278.65321.96421.65229.14329.66-84.8049.51 -7.707 318.59 276.64310.14 386.53 221.00302.55-67.9455.65 7.59 348.49 289.32331.52422.81231.12327.15-74.3258.20 4.378 295.04 258.54288.35 388.11 221.98303.46-93.0736.56 -15.11322.72 270.49308.25424.52232.23328.16-101.8038.25 -19.919 304.15 302.36302.82 272.13 258.28265.0932.02 44.08 37.74 324.26 318.77321.01290.13272.29284.3334.13 46.47 36.6810 300.76 299.14299.55 272.10 260.04265.9228.66 39.10 33.63 320.90 315.27317.60290.32274.07285.3130.58 41.20 32.2911 320.42 327.48324.36 266.89 271.33269.4653.53 56.16 54.90 342.05 345.68344.00284.91286.40289.0857.15 59.28 54.9212 327.73 329.88329.30 273.66 279.78277.5454.08 50.10 51.75 350.62 348.56349.52292.77295.63297.7157.85 52.93 51.8213 323.10 328.08327.34 274.90 292.65286.2848.20 35.44 41.06 345.39 346.91347.48293.86309.44306.8351.53 37.47 40.6514 316.62 314.23314.96 277.19 275.20275.9639.44 39.03 38.99 338.79 331.57334.11296.59290.39295.9742.20 41.18 38.1415 297.54 295.96296.49 277.57 270.68273.8619.97 25.28 22.62 317.85 311.79314.35296.51285.16293.8521.33 26.63 20.5016 310.37 315.47312.70 260.95 256.34258.3949.42 59.12 54.31 330.06 332.16330.71277.50269.91276.6152.55 62.25 54.1017 299.70 304.01301.76 258.15 261.49259.7741.55 42.52 41.99 318.17 320.35319.20274.06275.55278.4744.11 44.81 40.7418 286.78 287.91287.19 262.36 259.28260.7824.42 28.63 26.41 304.44 302.86303.46278.52272.73278.8925.93 30.12 24.57- 4 -19 285.89 295.87291.49 246.21 259.12253.2239.68 36.75 38.26 302.98 311.89308.02260.93273.15270.6642.05 38.74 37.3620 311.81 317.96314.85 255.63 255.76255.7056.18 62.19 59.14 330.61 334.49332.41271.04269.07273.1359.56 65.43 59.2821 306.35 285.71296.45 280.20 230.83254.9926.15 54.88 41.47 326.42 299.18313.07298.56241.71272.2827.86 57.47 40.7922 297.87 303.70301.47 260.66 274.54268.2737.21 29.16 33.21 316.54 322.32320.14277.00291.37288.0839.54 30.95 32.0623 302.42 297.78299.84 297.84 283.84290.62 4.58 13.94 9.21 323.48 315.15318.96318.59300.39312.69 4.90 14.75 6.2724 268.74 282.10275.45 231.49 242.89237.2637.26 39.21 38.19 283.36 296.32289.87244.07255.13252.7139.28 41.19 37.1625 279.13 283.49281.05 234.92 232.65233.7944.21 50.84 47.26 294.53 297.31295.65247.88243.99248.9046.65 53.31 46.7526 281.76 287.49284.48 243.58 243.86243.7238.18 43.63 40.75 297.82 301.88299.67257.47256.06259.7140.35 45.82 39.9627 271.71 281.61276.76 252.55 260.88256.8919.16 20.72 19.86 287.97 297.02292.58267.66275.16274.7720.31 21.86 17.8128 275.22 285.64280.71 253.05 261.63257.6722.17 24.00 23.04 291.79 301.35296.82268.28276.02275.7223.51 25.32 21.10 合计 304.34 294.88299.08 287.95 255.73270.9416.39 39.16 28.15 325.58 310.48317.27308.04269.25290.7817.53 41.23 26.49c月正反平衡发供电煤耗对比表日期发电煤耗[g/(kW·h)] 供电煤耗[g/(kW·h)] 正平衡 反平衡 差值 正平衡 反平衡 差值#3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计1 291.18 300.83296.51 202.21 241.12225.3488.97 59.70 71.17 308.20 318.33313.80213.30254.71237.8794.90 63.62 75.932 277.37 281.09279.51 218.72 270.19248.9958.66 10.90 30.52 293.34 295.12294.51229.98285.16262.3363.36 9.96 32.183 288.62 303.94297.02 223.68 276.23254.7164.94 27.71 42.31 305.17 320.64313.68235.47291.60268.5369.70 29.04 45.154 295.04 306.27301.12 230.89 270.38255.0664.15 35.89 46.06 312.33 322.94318.12243.44285.13268.9568.89 37.81 49.175 282.45 293.65288.27 232.53 260.23250.1649.92 33.42 38.11 299.03 309.33304.39245.26274.02263.6253.77 35.31 40.776 282.91 289.94286.78 221.07 261.27245.4861.84 28.67 41.30 299.74 306.33303.40232.61275.17258.4267.14 31.16 44.987 304.04 302.51303.12 234.18 258.90250.4169.86 43.62 52.71 324.24 320.24322.10247.10272.65263.9677.14 47.59 58.138 305.94 307.61306.51 239.24 257.64251.9066.70 49.97 54.60 326.20 324.90325.24252.38271.12265.3973.83 53.78 59.859 318.11 320.39318.86 236.46 257.11250.5081.65 63.27 68.36 339.60 340.90339.89249.37270.44263.8190.23 70.46 76.0810 293.25 299.00296.16 240.89 255.54251.6352.36 43.46 44.53 315.06 319.45317.32254.21268.76265.0660.85 50.69 52.2611 310.25 311.11310.78 236.08 251.94247.4574.17 59.17 63.33 333.49 331.98332.80249.09264.57260.4484.40 67.40 72.3612 306.20 307.12306.49 237.84 253.81249.1668.36 53.31 57.32 330.14 327.87328.78250.97266.82262.4079.17 61.04 66.3813 308.47 310.12308.98 238.08 256.52250.5970.39 53.60 58.39 329.88 329.19329.32251.20269.44263.7878.68 59.74 65.5414 276.83 249.90271.71 268.13 259.14266.788.70 -9.24 4.93 291.63 262.81286.12284.52272.71281.877.11 -9.90 4.25- 5 -15 319.56 323.80321.90 270.17 261.84268.7749.39 61.96 53.13 344.69 347.51346.36286.71275.43283.8857.98 72.07 62.4816 337.06 335.64336.09 266.98 258.49265.5970.08 77.15 70.50 362.80 357.53359.83283.23271.83280.4479.56 85.69 79.3917 326.95 325.71326.12 265.52 259.04265.0961.43 66.67 61.04 351.88 347.44349.39281.93272.39280.0269.95 75.05 69.3818 337.20 329.66333.08 362.21 257.90310.32-25.0171.77 22.76 365.60 352.32358.47392.55271.28330.96-26.9581.04 27.5019 346.72 342.53344.43 363.39 262.03313.26-16.6780.50 31.17 374.48 365.39369.77393.92275.76334.23-19.4489.64 35.5420 351.84 344.43347.86 365.04 262.20313.24-13.2082.23 34.62 380.14 367.03373.27395.97275.66334.07-15.8391.37 39.2021 365.11 359.69362.08 364.35 260.88313.680.76 98.80 48.41 397.52 385.47390.98395.62274.29334.79 1.89 111.18 56.1822 340.80 333.19336.61 362.60 263.18313.88-21.8170.01 22.73 370.08 356.14362.54393.26276.91334.96-23.1879.23 27.5923 354.32 348.36351.00 373.32 262.19317.51-19.0086.17 33.49 384.32 371.89377.61406.06276.11339.36-21.7495.78 38.2424 329.27 320.42325.35 372.68 265.84320.28-43.4154.58 5.07 357.32 340.52349.40405.02280.23342.45-47.7060.28 6.9525 320.92 310.85316.47 374.35 254.20319.22-53.4356.65 -2.75 348.62 330.58340.15407.19267.64341.61-58.5762.94 -1.4626 325.29 318.97322.61 314.31 321.17321.8110.98 -2.19 0.80 354.14 340.42347.76337.57341.25343.7516.57 -0.83 4.0127 350.08 340.86346.20 317.37 315.79320.6032.71 25.07 25.60 381.51 363.30373.12341.07336.10342.8240.44 27.20 30.2928 311.62 304.33308.53 313.50 320.53320.92-1.89 -16.20 -12.39338.24 324.28331.85336.97341.09343.23 1.27 -16.80 -11.3729 318.72 311.94315.48 308.58 322.77319.7310.14 -10.82 -4.25 348.06 334.09341.10331.36344.07342.0716.69 -9.98 -0.9630 312.51 308.62310.93 307.86 332.94324.30 4.65 -24.32 -13.37339.75 330.23335.41330.44354.86346.889.31 -24.63 -11.4731 310.06 305.61308.73 366.41 413.79394.48-56.36-108.18 -85.75339.17 328.12334.65393.38443.63423.22-54.21-115.51 -88.57 合计 319.38 316.56317.76 286.94 272.44282.7032.44 44.12 35.07 343.27 336.69339.76306.10287.37299.7837.17 49.33 39.98 将a月、b月和c月的数据汇总整理如下表：月份发电煤耗[g/(kW·h)] 供电煤耗[g/(kW·h)] 正平衡 反平衡 差值 正平衡 反平衡 差值#3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计 #3 #4 合计a 308.23 305.92306.60 286.94 272.44282.7021.29 33.47 23.91 328.82 322.67325.13306.10287.37299.7822.71 35.31 25.35b 304.34 294.88299.08 287.95 255.73270.9416.39 39.16 28.15 325.58 310.48317.27308.04269.25290.7817.53 41.23 26.49c 319.38 316.56317.76 286.94 272.44282.7032.44 44.12 35.07 343.27 336.69339.76306.10287.37299.7837.17 49.33 39.98- 6 -3原因分析正反平衡计算煤耗结果存在较大的非一致性，就说明已超出计算误差的允许范围，整个热力系的计量监测体系就存在一定的问题。