Energy saving technology for steam turbine operation transformation under variable operating conditions

Introduction to energy-saving technology for steam turbine

operation transformation under variable operating conditions

Keep the original ground foundation, adjustment, and auxiliary system of the steam turbine unit unchanged, and complete the compression shutdown renovation cycle within 40 days, plus 60 days of design and production preparation work before the steam turbine shutdown, for a total of 100 days. The original unit's upper cylinder and rotor assembly partition, generator rotor assembly return to the factory for processing, testing, and unit pre assembly.

For models with sub high temperature and sub high pressure, the original upper cylinder, lower cylinder, and rotor assembly of the extraction and condensation unit will be retained, and the pressure stage will be modified and replaced using a set rotor structure. The original extraction port will be used to transform it into a back pressure exhaust port. Through thermodynamic calculations, the original blade profile before the extraction port is modified and optimized. If necessary, the impeller and blades are synchronously designed and replaced, new baffles and gas seals are installed, and a cylinder sleeve structure is added to transform the original extraction work into the required back pressure parameter exhaust work. At the same time, the low-pressure end flow passage of the original unit was completely sealed with a partition, and the original low-pressure end power stage was completely removed and a new counterweight was added. The modified turbine rotor assembly and generator rotor assembly were subjected to dynamic balance testing before leaving the factory. Other auxiliary equipment will be modified and retained, and the original condensing system will be completely dismantled for high-temperature and high-pressure models. Based on the actual working parameters required for the forged rotor structure, it will be decided whether to retain the original rotor assembly. If it can be retained, the blade profile will be redesigned and replaced, and the original pressure level will be retained. On the contrary, a new rotor assembly must be replaced and other methods remain unchanged.

Including condensing and back pumping models, the original unit needs to be adjusted and modified for steam extraction or exhaust pressure and flow due to changes in actual working parameters. In response to this type of demand, thermal calculations are conducted to adjust the original unit pressure levels, change the blade profile, optimize the gas seal structure, and adjust the entire flow area to ensure that the operating parameters of the modified unit meet the actual working parameter requirements.

This type of renovation method has the characteristics of no need to replace new units, low investment, short renovation period, and unit operating efficiency not lower than that of new units. The economic and social benefits are both considerable, with a single project investment of 2-5 million yuan.