如何改造降低熱風爐排煙溫度以及精益效益分析

排煙熱損失是熱風爐各項熱損失中最大成都收賬一項，一般約為5%~12%，占熱風爐熱損失成都找人公司60%~70%。影響排煙熱損失成都收賬主要因素是排煙溫度，一般情況下，排煙溫度每增加10 ℃，排煙熱損失增加0.6% ~I .0%，相應多耗煤1.2% ~2.4%。若以燃用熱值為20000 kJ/kg煤收賬410 t/h高壓熱風爐為例，則每年多消耗近萬噸動力用煤。我國許多電站熱風爐成都找人公司排煙溫度高於設計值，約比設計值高20~50℃。所以，降低排煙溫度對於節約燃料、降低污染具有重要的實際意義。
The heat loss of exhaust gas is the largest one among all the heat losses of hot blast stoves, generally about 5%~12%, accounting for 60%~70% of the heat loss of hot blast stoves. The main factor affecting the heat loss of flue gas is the temperature of flue gas. Generally, the heat loss of flue gas increases by 0.6%~I.0% with the increase of 10 C, and the corresponding excessive coal consumption is 1.2%~2.4%. If the 410 t/h high pressure hot blast stove burning 20 000 kJ/kg coal is taken as an example, nearly 10,000 tons of power coal will be consumed every year. The exhaust gas temperature of many power plants in China is higher than the design value, which is about 20~50 degrees higher than the design value. Therefore, reducing the exhaust gas temperature is of great practical significance for saving fuel and reducing pollution. 以降低排煙溫度為目的的熱風爐技術改造的方案較多。考慮到大多數電廠熱風爐尾部煙道空間太小，防磨、防腐蝕要求較高，引風機的壓頭裕量不大等實際情況，我們采用利用低壓給水回收熱風爐排煙餘熱的低壓省煤器方案，受熱面形式則采用螺旋肋片復合擴展表面蛇形管，並且采用鎳鉻滲層零隙阻換熱管，以便達到在有限空間內最大限度降低排煙溫度並保證可靠運行的目的。采用該方案，入爐熱風溫度不受任何影響，且排煙溫度可以根據季節和煤質進行調節。
There are more technical transformation schemes for hot blast stoves to reduce exhaust gas temperature. Considering the fact that the tail flue space of hot blast stove in most power plants is too small, the requirements of anti-wear and anti-corrosion are high, and the pressure head margin of induced draft fan is not large, we adopt the low-pressure economizer scheme to recover the waste heat from hot blast stove exhaust by using low-pressure feed water, and the spiral fin compound expansion surface snake-shaped tube is adopted in the form of heating surface. The zero-gap resistance heat exchanger tube with nickel-chromized layer is used to minimize the exhaust gas temperature in a limited space and ensure reliable operation. With this scheme, the hot air temperature is not affected, and the exhaust gas temperature can be adjusted according to season and coal quality.
低壓省煤器及擴展表面強化換熱技術用於成都找人公司尾部受熱面改造是山東大學和濟南達能動力技術有限責任公司的成熟技術，已經成功應用於國內多傢電廠成都***的節能改造，在理論上也己發展到結構系統最優化的階段。在山東省，龍囗電廠於1997年6月投運瞭兩臺低壓省煤器（配2臺100MW機組），至今己運行瞭八年多，降低排煙溫度（165~135）30℃（且排煙溫度可調節），取得顯著效益。2003年龍口電廠200MW機組#5、#6爐采用低壓省煤器降低排煙溫度45℃，煤耗降低4.95g/kwh。威海電廠#2成都***於2003年10月投運瞭螺旋肋片管低壓省煤器（配125MW），降低排煙溫度（167~142）30℃，降低發電煤耗3.36 g/kwh。威海電廠#1熱風爐於2006年3月設計加裝低壓省煤器，濟寧運河電廠137MW機組#1、#2爐於2006設計加裝低壓省煤器，投運後降低排煙溫度（163~138）25℃，取得良好的使用效果。山西神頭一電廠200MW機組，#3、#4爐通過加裝低壓省煤器降低排煙溫度（176~156）20℃，取得良好的節能和环保效益。貴州黔桂電廠200MW機組#3、#4爐采用低壓省煤器降低熱風爐排煙溫度（176~156）25℃，取得良好的經濟效益。現在山西神頭一電廠#5、#6爐200MW，貴州黔桂電廠#5爐200MW機組，山東白楊河137MW機組（循环流化床），華能海口電廠125MW熱風爐機組低壓省煤器項目工程進行中，遼寧清河電廠200MW機組和山西古交發電廠300MW機組也準備采用低壓省煤器降低排煙溫度，實現降低煤耗和脫硫工程需要的目的。
Low-pressure economizer and extended surface heat transfer enhancement technology are mature technologies of Shandong University and Jinan Daneng Power Technology Co., Ltd. for retrofitting the tail heating surface of hot blast stove. They have been successfully applied to energy-saving retrofitting of hot blast stoves in many domestic power plants and have developed to the stage of optimizing the structure system in theory. In Shandong Province, Longkou Power Plant put into operation two low-pressure economizers (with two 100 MW units) in June 1997. It has been operating for more than eight years, and has achieved remarkable benefits by lowering the exhaust temperature (165-135) by 30 C (and the exhaust temperature can be adjusted). In 2003, low pressure economizer was used to reduce the exhaust gas temperature by 45 C and coal consumption by 4.95g/kwh in # 5 and # 6 boilers of 200 MW units in Longkou Power Plant. The low-pressure economizer with spiral finned tubes (equipped with 125MW) was put into operation in #2 hot blast stove of Weihai Power Plant in October 2003. The exhaust gas temperature (167-142) was reduced by 30 C, and the coal consumption of power generation was reduced by 3.36 g/kwh. Low-pressure economizer was designed and installed in #1 hot blast stove of Weihai Power Plant in March 2006. Low-pressure economizer was installed in #1 and #2 boilers of 137MW unit of Jining Canal Power Plant in 2006. After putting into operation, the exhaust gas temperature (163-138) was lowered by 25 degrees, and good results were achieved. For 200 MW units in Shanxi Shentou No. 1 Power Plant, # 3 and # 4 boilers are equipped with low-pressure economizers to reduce the exhaust gas temperature (176-156) by 20 C, thus achieving good energy-saving and environmental protection benefits. The low pressure economizer is used in the #3 and #4 boilers of 200 MW units in Guizhou Guizhou Guizhou Power Plant to reduce the flue gas temperature (176-156) of the hot blast stove by 25 degrees, and good economic benefits are obtained. Now Shanxi Shentou No.1 Power Plant, Guizhou Guizh透水地坪ou Guizhou Power Plant, Guizhou Guizhou Guizhou Guizhou Power Plant, Shandong Baiyanghe 137MW unit (circulating fluidized bed), Huaneng Haikou Power Plant 125 MW hot blast stove unit low pressure economizer project is in progress, Liaoning Qinghe Power Plant 200 MW unit and Shanxi Gujiao Power Plant 300 MW unit are also印花地坪 prepared to use low pressure province. The utility model reduces the exhaust gas temperature and realizes the purpose of reducing coal consumption and desulfurization project requirements.
根據已加裝低壓省煤器電廠使用情況，在進行熱力計算和技術經濟比較的基礎上，得出以下可行性結論：
On the basis of thermodynamic calculation and techno-economic comparison, the following feasible conclusions are drawn according to the operation of power plants with low-pressure economizer installed.
1）熱風爐尾部煙道空間可以安排佈置開全部低壓省煤器受熱面；
1) the space of the tail flue of hot blast stove can be arranged to arrange all the low pressure economizer heating surfaces.
2）汽輪機的熱力系統及參數適於進行低壓省煤器的改造；
2) the thermodynamic system and parameters of the steam turbine are suitable for the transformation of the low pressure economizer.
3）設備投資節省，回收期很短，技術經濟可行；
3) the equipment investment is saved, the recovery period is very short, and the technology is economical and feasible.
4）擴展表面制造工藝和質量己全部過關。
4) extend the surface manufacturing process and quality.
綜上所述，加裝低壓省煤器降低排煙溫度的熱風爐改造，不僅具備必要性、緊迫性，而且具備瞭可行性。
In summary, the modification of hot blast stove with low pressure economizer to reduce the exhaust gas temperature is not only necessary and urgent, but also feasible.