吸收式热泵技术在空冷供热机组中的应用

Application of Heat Pump Technology in Air Cooling Steam Turbine

吸收式热泵技术是在高温热源的驱动下提取低温热源的热能,输入到供热热源中的一种技术。某供热电厂2×300 MW空冷凝汽式机组供热能力达到极限。因此考虑在不增加电厂供热抽汽量及不改动热网首站的前提下,采用吸收式热泵及凝结换热技术,回收2×300 MW机组的汽轮机乏汽余热,以增大供热面积。按照机组实际运行参数,每台机组选择2台XR2.0-15-7000型吸收式热泵,并在热泵前并联前置换热器以提高吸收式热泵的能效比。通过热平衡计算,采用吸收式热泵技术后,预计每年可回收乏汽余热约2700 TJ。实际运行中,热网总供水温度提高6～8℃,机组供热抽汽量减少80 t/h,新增供热面积1.020 km2,余热回收系统运行稳定,节能效果明显,对安全稳定供热起到良好的保障作用。

Absorption heat pump technology is under the drive of high temperature heat source to extract heat source of low-temperature heat enegery and input to the heating heat source. Heating capacity of 2×300 MW air-cooled condensing units in some power plant reach to its limit. Thus consider to take absorption heat pump and condensation heat transfer technology without increasing heating extraction and without changing the network in the power plant, to retrieve steam turbine exhaust heat, to enlarge heating supply area. Based on the actual operation parameters, every unit select two XR2.0-15-7000 type absorption heat pump, and parallel leading heat exchanger in order to improve the absorption heat pump energy efficiency. Through heat balance calculation, after using the absorption type heat pump technology, the recycling steam exhaust heat is expected to be about 2700 TJ a year. In the actual operation, the heat-supply total water temperature increase from 6 to 8℃, the volume of unit heating extraction was reduced 80 t/h, the extra heating area was 1.020 km^2. The waste heat recovery system ran stable, energy saving effect was obvious.