The Research Of Power Plant Air Condensing Steam System With Closed Type Stand Pipe Indirect Evaporative Chiller

Power air condensing steam system in the popularization and application of coal-fired power plants in north China, The global climate change has become increasingly serious, To air cooling technology put forward higher requirements in the summer heat and winter cold running environment, both should be considered in the energy conservation and water saving, and make sure the summer/winter crew can Full load run, It is enjoys potential applications for evaporative technique high efficiency, water saving, energy saving in the north.Based on the predecessors’ research in traditional open evaporative chiller, first analyzes the characteristics of vertical tube type indirect evaporative module unit, and combined with horizontal tube type indirect evaporative section of the application effect in the evaporative ventilation and air conditioning equipment for the actual test and analysis, and the vertical tube type indirect evaporative cooling section of the test bench tests and comparative analyses of the performance, experimental results show that under the same inlet parameters, both can reach about 5 ℃ temperature drop effect, the cooling efficiency of over 60%, Xi’an yang regional experiment in vertical tube type indirect evaporative module test unit best air volume ratio 0.7, best to drench water density should be controlled in the range of 1197-2057 kg/h(m.), test the maximum temperature drop of 9.2 ℃, Taken structural characteristics of both, Compared to vertical horizontal tube type indirect evaporative module unit used in evaporative cooling water chiller unit volume, congestion, reduce the advantages of air side resistance at a time, It has the unit volume, congestion, once the advantages of the air side resistance decrease, has good application prospect.According to air condensing steam system of cooling demand, combined with the vertical tube type indirect evaporative module unit performance testing, in reference to traditional open design characteristics of evaporative cooling chiller, corresponding to the closed circulating water cooling system used for air condensing steam aspect riser indirect evaporative chiller design. Consider the first time design, according to the traditional experience is relatively rich in evaporative chiller parameters, design a in and out of the water flow to 25 m3 / h, The closed riser indirect evaporative chillers in and out of the water temperature is 5 ℃, To design the main components in the units(vertical tube type indirect evaporative section, packing section, closed heat plate section), according to the result of energy consumption of main parts design and equipment selection.Through the analysis of the current power plant air condensing steam system main types and their characteristics, summarizes the different air condensing steam system in the main problems existing in the operation, the analysis results show that the existing main air condensing steam system operation high summer temperatures, air condensing steam system efficiency decline and windy weather caused by a lack of efficiency of cooling unit back pressure increases, power generation coal consumption rise, generating set safety performance. And analysis of several kinds of evaporative technology applied in the air condensing steam system, put forward the surface type condenser system considering closed riser of indirect evaporative cooling water chillers as the peak cooling device system combination scheme.Combined with the actual closed riser tube type indirect evaporative chiller opposites of indirect evaporative section of the test, and the unit in high humidity area living hot water(around 90 ℃) straight line cooling and high temperature hot water(about 50 ℃) circulating cooling factory test, and it applied in some power plants Yulin crew tower circulation cooling pool, field monitoring running effect around the unit for ten days, factory test and field test results show that the vertical section temperature drop in high humidity area around 3.5 ℃, the efficiency can reach 65%, basic pipe outside wind speed 1.3 m/s, the tube when the wind speed 4.2 m/s is the best cooling effect, dry areas between 6-8 ℃ temperature drop, efficiency is about 75%, to 90 ℃ in-line hot water cooling, the unit average temperature drop to 30 ℃, 50 ℃ circulating water cooling temperature drop in around 20 ℃, 30 ℃ water environment, the temperature drop of unit for between 3-5 ℃. At the scene of the unit under the water temperature is about 30 ℃, basic maintain at about 4.5 ℃, in and out of the water temperature difference between water tank water temperature is less than about 1 ℃, outdoor air temperature calculation efficiency of the unit and the wet bulb for between 90% and 100%, the efficiency is low, Analyzes the reasons for the low test and field test. At the same time, puts forward the optimization measures of the unit: briefly shower filter water impurities, ensure to drench water flow and secondary air inlet air flow, etc.Combined with the unit test results, the application efficiency of the wet bulb theoretical analysis of major cities across the country for circulating water temperature, and form the chart, and example expansion after the unit in the 2 × 350 MW air cooling unit as the peak cooling device, according to the experience of the relevant manufacturer, a rough calculation can be realized between the cooling tower circulating water temperature 1.7 ℃, reduce system back pressure is roughly 1.81 k Pa, save income of 2.091 million Yuan, payback period is 9.6 years, have certain of economy, but also need to make the unit expansion after the actual research.