| This paper describes the industrial tests on the main gas parameters having impact on TRT power, the flow rate, pressure, temperature and dust content of the gas into turbine. The test results show that optimized process parameters have better influences to the improvement of TRT power.As for the increasing flow rate of gas into turbine and reducing gas leakage so that more gas acts on turbine's performance, the joint regulation with speed regulation valve, stator blade and reducing valve for BF top pressure is changed to fully stator blade regulation. Thus the gas leakage caused by operation of reducing valve is eliminated. In practice, the judgement method for gas leakage of butterfly valve is developed, therefore the operators at site could be informed andcarry out corresponding operation earlier. Besides, it improves the regulation quality of BF top pressure ,reduces pressure losses occurred at control angle of speed regulation valve. Therefore the turbine is capable of recovering more pressure energy. With the measures above mentioned, the hourly power generation of TRT is increased to over 4500kW.In order to reduce pressure losses before entering turbine to have gas of higher pressure act on TRT , the gas wet clean system of 4# BF is optimized. A lot of special industrial test are made on the resistance losses of dual-venturi system , setting of spiral- flow dewaterer, water supply volume of dual- venture system and control of water pressure . According to the tests .the system pressure losses before entering turbine could be reduced to 25kpa,and theannual recovered electricity by TRT is increased by 1,800,000 kWh.In order to effectively increase gas temperature at TRT entry and increase turbine delivery as well as to ensure gas quality at exit of gas cleaning system, the water supply process and packing layer of the packing dewaterer are upgrade based on industrial tests .By reducing water supply volume, the gas temperature at entry of turbine is increased to 60癈,and the annual recovered electricity by TRT is increased by 1,855,000 kWh.As for the blast scaling of turbine which influences TRT power generation capacity, solutions for scaling prevention and corrosion mitigation are found through lab and plant tests ,the power losses caused by intermittent maintenance is avoided as well as equipment maintenance costs are reduces. Relatively ideal status is recovered regarding TRT power generation and maintenance cycle.Through looking up in a lots of information domestic and abroad regarding gas dry cleaning of large blast furnace, investigation and researches in Capital Iron Steel Complex, Panzhihua Iron and Steel Company as well as Wuhan Iron and Steel(Group) Company etc., basic design (process part) and relevant economic calculation are made for gas cleaning of 2200 m blast furnace .The comparison between gas wet and dry cleaning processes indicate that the gas dry cleaning system not only increases TRT power generation capacity, but also reduces power consumption, water consumption, chemical consumption, maintenance work and coke ratio of the existing gas wet cleaning system as well as improves heat efficiency.Therefore, the gas dry cleaning process for large blast furnace features bright Prospect and requires sooner development.
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