How does fgd work

Download Now Download Download to read offline. Flue gas desulphurization detailed process Download Now Download Download to read offline. What to Upload to SlideShare.

A few thoughts on work life-balance. Is vc still a thing final. The GaryVee Content Model. Mammalian Brain Chemistry Explains Everything. Related Books Free with a 30 day trial from Scribd. Dry: A Memoir Augusten Burroughs. Related Audiobooks Free with a 30 day trial from Scribd.

Empath Up! Rodeo Lokash. Himanshu Panchal. Rahul Rohit. Mukesh Kumar. Yeruva Reddy. Show More. Views Total views. Actions Shares. No notes for slide. Flue gas desulphurization detailed process 1. The agitator is provided to keep the slurry solids in suspension during tank usage. Limestone slurry in the limestone slurry storage tank of flue gas desulfurization FGD system will be pumped to absorber by the limestone slurry feed pumps.

Limestone slurry is added to the absorber to replenish limestone consumed by chemical reaction with the absorbed sulfur dioxide. The slurry addition rate is controlled by a pH control system based on the pH in the absorber.

And then, from absorber, treated flue gas will flow via the GGH treated side to the stack. Flue gas enters the absorber near the bottom of the spray-tower and flow upward to react with a descending spray of finely divided droplets of recycle slurry.

The slurry contains the alkali needed to react with SO2. Intimate contact of the flue gas with the alkaline limestone slurry is achieved in three successive spray zones. Each spray bank is provided with a series of spray nozzles designed to achieve proper automization of slurry. The absorber reaction tank volume is adequately sized to provide sufficient retention time for limestone dissolution, oxidation of calcium sulfite to calcium sulfate gypsum , and promte gypsum crystal growth.

Each absorber recirculation pump is dedicated to a single spray bank. The absorber reaction tank is designed with sufficient delay time and adequate agitation to ensure optimum utilization of limestone and crystallization as well as precipitation of gypsum. Oxidation of calcium sulfite to calcium sulfate or gypsum is also accomplished in the reaction tank. Oxidation fans supply the air to lances submerged in the recycle tank for the oxidation reaction.

The oxidation air is quenched with adequate amount of raw water to avoid nozzle plugging. A two-stage mist eliminator is provided at the top of the absorber. The first stage mist eliminator removes the bulk of the entrained liquid droplets from the gas stream. The mist eliminators are washed intermittently to maintain clean surfaces and low gas-side pressure losses. KGaA uses cookies to be able to optimally design and continually improve its web site.

By continuing to browse the web site you consent to the use of cookies. In a f lue g as d esulphurisation system FGD , sulphur compounds are removed from the exhaust emissions of fossil-fuelled power stations. A shower of lime slurry is then sprayed into a flue gas scrubber, where the SO 2 is absorbed into the spray and becomes a wet calcium sulfite. One by-product of that sulfite is it can be converted to salable gypsum.

Wet scrubbing provides high-efficiency sulfur dioxide removal capacity, in addition to reducing any scaling potential. The circulating water used during the wet scrubbing process ends up with many contaminants and pollutants, and the composition can vary significantly, plant to plant, influenced by factors such as the coal and limestone composition.

In order for operating conditions to be properly maintained, this FGD wastewater needs to be discharged constantly from the scrubber system through a purge stream consisting of contaminants from coal, limestone, and the makeup water.

The water is typically supersaturated with gypsum, is highly acidic with high concentrations of total dissolved solids TDS and total suspended solids TSS , chlorides, fluorides, nitrites and nitrates, along with trace metals such as arsenic, mercury, selenium, boron, cadmium, and zinc.

Flue gas desulfurization wastewater can be effectively and efficiently treated using large filter presses or large vacuum belt filters for very large sludge production. Recess chamber filter presses are used effectively in coal-fired power plants to separate the solids from liquids in the purge stream. The FGS sludge dewatering process results in formation of large volumes of dry filter cake for proper disposal in a landfill.