Study On Reform Of Removal Salt System By RO In A Power Plant

Compared with traditional thermal power plants,the gas turbine power plant is more cleanly on power generating. The main fuel of the power plant is fuel oil, natural gas or industrial associated gas. During the operation process, the pollutant emission and noise are relatively small. The internal combustion engine is the core equipment of the gas turbine power plant, and it is widely used at home and abroad because of its advantages such as quickly installed, small size, lower operating costs and longer life. The boiler replenishment of the gas turbine power plant has the strict request on water quality, the replenishment needs rigorous treatment to be used. The traditional treatment process is ion exchange or reverse osmosis system plus the ion exchange. With the continuous development of the membrane separation technology, the whole film process has been applied in power plant water treatment, and it is proved that the whole film process has low operating costs and stable water quality.This transformation is for the No. 2 water treatment system of a particular gas turbine power plant. The process of the treatment system is reverse osmosis plus the ion exchange process. The process design capacity of water production is 30m~3/h, for the equipment of the treatment system has been running for 17 years and seriously aging, the capacity of water production is less than 26m~3/h. Frequent outages due to the equipment failure have serious impact on production. Therefore it is needed to transform the No. 2 water treatment system.The new system features the full membrane treatment system (UF + RO + electric desalting), and the water treatment process is divided into two steps as pre-treatment and desalination treatment. Pre-processing is mainly used for removal of suspended solids, colloids and organic matter, and to ensure that the organic matter content and the water pollution index (SDI) to meet the reverse osmosis and EDI water requirements. The pre-processing equipments of this project are mainly about multi-media filters, disc filters (the original), screen filter and UF fine filter. The desalination treatment is divided into pre-desalination and refined desalination treatment. The pre-desalination is mainly used for removal of most of the inorganic ions in water; the refined desalination is mainly used for further desalination treatment. This project mainly uses reverse osmosis as pre-desalination treatment equipment, and the EDI device as refined desalination treatment.Through the commissioning, the system has a stable capacity at 45 m~3 / h, the effluent quality meets the design requirements. The first reverse osmosis rate is 75%, the second reverse osmosis system is 78%, and the EDI device recovery rate is 90%. And the new system is stable.The total investment of the transformation project is 4.55 million, the running costs of the new system is 3.16 yuan / t ? h, far below the cost of the old system's 4.11 yuan / t ? h. More than 0.33 million yuan can be saved after running for a year. During the operation of the new system, emissions and labor intensity can be significantly reduced, and better environmental and social benefits will be achieved.