The latest Ammonia based FGD technology of JNG China is adopted on flue gas desulfurization system of the 3 *480 t/h, high temperature and pressure pulverized coal boiler, with annual output of 1 million tons of synthetic ammonia and 1.75 million tons of urea in the phase-I of China Coal Erdos Energy& Chemical Co., Ltd., . Under the design condition, the desulfurization efficiency should be not less than 95%. The original design emission value is: SO₂ emission concentration ≤ 80mg/Nm³, ammonia slip ≤ 8 mg/Nm³, and dust concentration ≤ 30 mg/Nm³.
Contribute to the three sets of ammonia desulfurization units adopt the ammonia gas of the phenolic ammonia recovery by the owner as the absorbent (the H2S, phenol, oil and other indexes in the ammonia water exceed the ammonia water quality requirements of the ammonia desulfurization absorbent), the ammonium sulfate solution in the absorber often fail to crystallize normally. It formed a vicious circle of the system: decreased in oxidation rate, ammonia slip from the chimney outlet, the total particulate matter exceeded the original design value, the plume tail gas phenomenon, and poor visual effect of exhausting flue gas. Affected by the tailing of the flue gas, the flue gas carried residual SO₂ condensation, which formed acid rain drops to ground to cause corrosion to the accessory equipments. Especially the thermal insulation of the desulfurization absorber accessory equipment, the steel structure and bolts were seriously corroded, and there were major safety risks. In view of the increasingly strict environmental protection requirements, in order to eliminate the safety risks caused by acid rain corrosion, the owner chose our latest technology to retrofit the existing three ammonia desulfurization units to eliminate flue gas tailing and reduce PM emissions. After the retrofit, the emissions are as below: the total outlet particulate matter content ≤ 20 mg/Nm³, the ammonia slip concentration ≤ 5 mg/Nm³, and the ammonia recovery rate ≥ 98%.
On 14th December , 2017, the 1#, 2#, and 3# absorbers successfully passed the 168 Hours Reliability Test. During the period of test, the emission values of 1#, 2#, and 3# absorbers all met the requirements of the technical agreement , and the owners were quite satisfied with our advanced technology.