Cement Energy and Environment

technologies that have been ongoing in a number amount of S02 emissions from power plants and of countries for several years. other industrial facilities. FGD is a set of At power plants, flue gas is often treated with a series of chemical processes and scrubbers, which remove pollutants. Fossil fuels such as coal and oil contain a significant amount of sulphur. When fossil fuels are burned, about 95 per cent or more of the sulphur is generally converted to S02. Such conversion happens under normal conditions of temperature and of oxygen present in the flue gas. Electrostatic precipitators or fabric filters remove particulate matter and flue-gas desulfurisation captures the S02 produced by burning fossil fuels, particularly coal. Lime or limestone slurry, used as a scrubbing media, is abrasive and often contains small amounts of chlorides and fluorides which can cause severe corrosion in metal piping. Fiberglass Reinforced Polymers (FRP) are the overwhelming choice for this application since it is resistant to abrasion and corrosion Flue gas desulfurisation (FGD) Flue gas desulfurisation is commonly known as FGD, and is the technology used for removing S02 from the exhaust combustion flue gases of power plants that burn coal or oil to produce steam for the turbines that drive their electricity generators. The most common types of FGD contact the flue gases with an alkaline sorbent such as lime or limestone. Most FGD systems employ two stages: one for fly ash removal and the other for S02 removal. Attempts have been made to remove both the fly ash and S02 in one scrubbing vessel. However, these systems experienced severe maintenance problems and low removal efficiency. In wet scrubbing systems, the flue gas normally passes first through a fly ash removal device, either an electrostatic precipitator or a wet scrubber, and then into the S02 absorber. However, in dry injection or spray drying operations, the S02 is first reacted with the sorbent, and then the flue gas passes through a particulate control device. As S02 is responsible for acid rain formation, stringent environmental protection regulations have been enacted in many countries to limit the technologies used to remove S02 from exhaust flue gases of fossil-fuel power plants, and from the emissions of other sulphur oxide emitting processes. Due to the corrosive nature of the scrubbing process, the selection of the MOC is vital to successful operation of the power plant. FRP -the preferred material A variety of materials have been successfully used in wet FGD systems including rubber lined carbon steel , flake glass filled epoxy vinyl ester resins, high nickel alloy clad carbon steel, rdckel based alloys , and FRP that are based on epoxy vinyl ester resins and epoxy novolac vinyl ester resins FRP was selected as the preferred material of construction based on the cost-effectiveness, ease of installation and performance under the severe conditions created during the scrubbing process. One of the many advantages of using FRP is that they can be formulated to be corrosion resistant. The type and thickness of this corrosion barrier/liner will depend upon the specific service environment. Corrosion resistance of FRP is a function both of resin content and the specific resin used in the laminate. Generally speaking, the higher the resin content, the more corrosion resistant the laminate. To increase the abrasion resistance of composite minerals in correct combination is added as filler in right proportion. Features • Excellent wear resistance demonstrated in high speed slurry conveying processes. • Maintains the corrosion resistance feature of FRP composite pipes. • WearShield pipes weigh as little as 1/6th of steel pipes and 1/20th of concrete pipes. • Ability to design seamless inner surfaces for trouble free flow over long distances. • Demonstrated to provide superior benefits in FGD systems and abrasion slurry conveying application. Application For coal fired power plants in conveying of coal ash slurry. For limestone slurry which is used 34 .. .. ..