Recently, the super-cleaning emission FGD project for 1000MW unit of Shanghai Caojing Power Generation Co., Ltd., contracted by Yuanda Engineering, was put into operation.
The project is one of the first batch of NOx, SO2 and de-dust super-cleaning emission demonstration projects appointed by National Energy Administration.
With the data taken during operation, it’s indicated that project performance is in good condition. SO2 concentration is 1019mg/Nm3 at absorber inlet and 12.23mg/Nm3 at absorber outlet. FGD efficiency is 98.799%. Dust concentration is 23.96mg/Nm3 at absorber inlet and 3.04mg/Nm3 at absorber outlet. Absorber de-dust efficiency is 87.3%. SO2 and dust emission is below gas turbine emission standard required by Ministry of Environmental Protection, which is close to zero emission.
There are several technological innovations in this super-cleaning emission project. Firstly, design a slurry tank outside absorber and connect slurry sump within absorber to the slurry tank outside. Adjust pH value of slurry inside and outside absorber by limestone slurry feeding system, to improve FGD efficiency. Secondly, add a wall ring thus flue gas within the absorber can distribute evenly, which prevents the problem of bias current. Thirdly, adopt double-phase rectifying equipment, which is proprietary technology of Yuanda Engineering. When slurry is spayed upon the surface of double-phase rectifying equipment, liquid membrane with certain height will take shape. The membrane will extend the retention time of flue gas in absorber. While liquid and gas fully contact, dust in flue gas is washed off, so as to reduce dust in flue gas and increase FGD efficiency.
Caojing project utilizes Yuanda Engineering’s proprietary technology and comes to be the first demonstration project of this new technology within CPI group.