1. Consumption process
1.1 the flue gas desulfurization system is composed of the following main subsystems:
(1) Flue gas system
(2) Sulfur dioxide absorption system
(3) Limestone slurry preparation system
(4) Gypsum dehydration system
(5) Process water system
(6) Compressed air system
(7) Waste water system and slurry emptying system
(8) Electrical and lighting system
(9) Control system
(10) Fire fighting and fire alarm system
Flue gas system: the main function of the flue gas system is to introduce the raw flue gas from the main flue at the boiler side into the absorption tower, and the net flue gas after desulfurization and purification is introduced into the chimney for discharge.
Absorption tower system: the flue gas enters from the lower side of the absorption tower and contacts with the limestone slurry sprayed on the upper side countercurrent, stops the chemical reaction in the tower, and stops the oxidation reaction on the reactants falling into the slurry pool of the absorption tower, so as to obtain the desulfurization by-product dihydrate gypsum. The clean flue gas washed with absorbent and desulfurized is led out from the upper side of the absorption tower and discharged into the chimney after the mist drops are removed by the demister.
Limestone slurry preparation system: limestone powder with a particle size of 325 mesh (passing rate greater than 90%) is pumped into the limestone powder silo by the car, and then transported to the limestone slurry tank by the spiral weighing feeder through the star feeder. Water is added into the limestone slurry tank to make about 20-30% limestone slurry, and then pumped to the absorption tower through the limestone slurry.
The system is equipped with two steel limestone powder silos. The total capacity of the silos is designed according to the limestone powder consumption of two boilers operating for 3 days under BMCR working condition, and the effective volume is 2*1100m3. Each limestone powder bin is equipped with two discharge ports, each corresponding to a star feeder and a spiral weighing feeder.
The effective volume of limestone slurry tank meets the 6-hour consumption of two boilers under BMCR working condition, and the effective volume is 2*300m3. There are four limestone slurry pumps, two for each absorption tower, one for operation and one for standby. A connecting pipe is set between the two slurry tanks, and the pulping systems on both sides can be standby for each other.
Process water system: the process water system can meet the water consumption of FGD process system under normal operation and accident conditions of FGD installation. The process water system can supply water to the following equipment:
(1) Wash the demister of the absorption tower.
(2) Limestone pulping and oxidation air cooling of absorption tower and liquid level adjustment of slurry pool.
(3) Wash gypsum and vacuum belt dehydrator.
(4) Equipment cooling, sealing and pipeline flushing of desulfurization system.
(5) Other water.
The process water system is the main pipe, and the desulfurization of two boilers is common; The process water pump is designed as 2*100% capacity, and the demister flushing water pump is designed as 3*100% capacity. A manual connection door is set between the main pipe of the process water system and the flushing water main pipe of the demister, which is opened during operation to improve the reliability of the water used in the system.
Gypsum dehydration and storage system: the gypsum slurry in the absorption tower is sent to the gypsum slurry cyclone for concentration through the gypsum slurry discharge pump, and the concentrated gypsum slurry flows by itself * * * the vacuum belt dehydrator stops dehydration. After dehydration, gypsum with a moisture content of less than 10% and a purity of more than 90% is sent to the gypsum stacking room for storage and outward transportation.
Two vacuum belt dehydrators are set, and the output of each one is configured according to 75% of the total output of FGD gypsum when two boilers burn design coal under BMCR working condition, with the output of 53.1t/h.
The above is a detailed introduction about biogas desulfurization, which I hope will be helpful to you If you have any questions, please contact us We will provide you with professional service http://www.hdtvorigin.com