Why do flue gases desulfurize?
Flue Gas Desulfurization (FGD) Processes. In many plants it is necessary to remove sulfur from the flue gases after the combustion process to meet environmental requirements.
How does a flue gas scrubber work?
The basic principle of scrubbing is that flue gases are forced through a system of baffles within a smokestack. The baffles contain some chemical or chemicals that remove pollutants from these gases.
How is SO2 removal from flue gases?
For the removal of SO2 from flue gas, a wet process using calcium carbonate as an absorbent is most commonly adopted in commercial plants. The wet process shows a high efficiency but needs a large amount of water. SO2 is fixed in the form of calcium sulfate.
Why is desulphurization needed?
The principle of desulphurization is to transfer the sulfur dissolved in the liquid steel to a CaO-rich slag phase. This process is typically carried out in a ladle furnace (LF). For this process to be successful, two conditions need to be fulfilled: The slag must be fully liquid (liquid fraction > 0.9).
What is desulphurization of fuel?
Fuel desulfurization involves reduction of sulfur from the fuels prior to combustion. Sulfur in coals is present in three forms: pyritic, organic, and sulfatic.
What is flue gas scrubbing?
Flue-gas scrubbing refers to the removal of pollutants from industrial exhaust systems. In general, a scrubber system uses liquids to remove pollutants, but, recently, scrubbers using dry reagents or slurries have been used successfully to limit particulate pollution, sulphur dioxide and other harmful emissions.
What is desulphurization process?
Desulfurization or desulphurisation is a chemical process for the removal of sulfur from a material. This involves either the removal of sulfur from a molecule (e.g. A=S → A:) or the removal of sulfur compounds from a mixture such as oil refinery streams.
What is meant by desulphurization?
Definition of desulfurization : the removal of sulfur or sulfur compounds (as from coal or flue gas)
What is the process of scrubber?
Process description A scrubber is a waste gas treatment installation in which a gas stream is brought into intensive contact with a liquid, with the aim of allowing certain gaseous components to pass from the gas to the liquid. Scrubbers can be employed as an emission-limiting technique for many gaseous emissions.
What is the importance of desulphurization?
These processes are of great industrial and environmental importance as they provide the bulk of sulfur used in industry (Claus process and Contact process), sulfur-free compounds that could otherwise not be used in a great number of catalytic processes, and also reduce the release of harmful sulfur compounds into the …
Why desulphurization of coal is needed?
Most of research work on coal desulfurization has been focused on pyritic sulfur removal, which represents in most cases at least half of the total sulfur content in coal, since organic sulfur is more difficult to be removed by conventional processes. Desulfurization aims mainly at breaking down the pyrite lattice.
How is organic Sulphur removed from coal?
Chemical desulfurization has become the main desulfurization method because of its short reaction time and high desulfurization rate. Ma et al. treated high-sulfur coal with 0.25 mol/L sodium hydroxide and then with a hydrochloric acid (HCl) solution and obtained an organic sulfur removal rate up to 73%.
How do you desulfurize coal?
Chemical Desulfurization Methods Chemical desulfu- rization methods based on the treatment of coal with various oxidizing agents, ferric sulfate, hydrogen peroxide, and performic acids are effective for the removal of ash and pyretic and sulfate sulfur, but yield only a small reduction of organic sulfur.
What is flue gas desulfurization?
Flue Gas Desulfurization Processes The process of FGD is designed to absorb the sulfur dioxide in the flue gas before it is released. This is accomplished through either a wet or a dry process.
How do you get rid of sulfur dioxide in a flue?
SNOX Flue gas desulfurization removes sulfur dioxide, nitrogen oxides and particulates from flue gases; Dry sorbent injection systems that introduce powdered hydrated lime (or other sorbent material) into exhaust ducts to eliminate SO2 and SO3 from process emissions.
What are the specific issues with the desulfurization process?
Specific issues include the degree of desulfurization that the process can offer as well as its flexibility.
Where does sulfur dioxide come from when it is desulfurized?
Before flue gas desulfurization was installed, the emissions from the Four Corners Generating Station in New Mexico contained a significant amount of sulfur dioxide. 2) from exhaust flue gases of fossil-fuel power plants, and from the emissions of other sulfur oxide emitting processes such as waste incineration .