PRECIPITATED LIME STONE (PRECIPITATED CALCIUM CARBONATE)

The commercial grade of calcium carbonate in manufactured in two forms. * Precipitated Calcium Carbonate, * Activated Calcium Carbonate. These two forms of calcium carbonate differ in respect of coating which the former does not have and later has. Both the forms of calcium carbonate are being used in various industries as filler or extender, thus assumes crucial importance in chemical and allied industries. PVC Rubber, denitrifice, cigarette paper, printing ink, pharmaceutical are some of the calcium carbonate using industries. In this offer we have considered the product mix of Precipitated Grade which could cover very wide range of grades in terms of Particle Size, Shape and Distribution. It will be possible to vary any of the three physical properties alongwith other physical properties, such as Bulk Density, Flow Point, Viscosity, as required by individual customers as per their need. We have also considered 40 Tons per day capacity Activated Calcium Carbonate with different coating arrangement as well as sophisticated Pressure Filtration and Drying System to ensure the quality product. High Grade Lime stone containing more than 90% CaO is calcined in a lime kiln fired by coal to obtain burnt lime (CaO). For manufacture of Precipitated Calcium Carbonate, the burnt lime is converted into a thin slurry containing 15-20% of calcium hydroxide by adding required quantity of water and stirring in a mixing tank. The solution is passed through a cyclone separator for removing impurities like sand. The clean slurry is transferred into a carbonating tower. The flue gases from the lime kiln containing 20-30% carbon-dioxide are collected and scrubbed with water in a scrubbing tower to remove dust and other impurities. The clean gas in compressed with the help of compressor and bubbled through the lime slurry solution in the carbonating tower. The calcium hydroxide in the solution reacts with carbon di oxide in the gas to form calcium carbonates. The contents of the carbonator are kept under circulation with the help of a pump to prevent settlement of the product. After completing the carbonation, the slurry is passed through a vacuum rotary filter to obtain precipitated calcium carbonate in the form of wet cake containing 40-50% moisture. The filtered water is collected and recycled for making lime slurry. The wet cake of calcium carbonate is dried in a tray drier and pulverized to the required mesh in a micro pulverized. The product after testing is packed in polythene bags of 50% kgs. Each for marketing. Calcium Compounds. Calcium compounds such as calcium carbonate, calcium phosphate and calcium sulphate are widely distributed in nature. A large number of them are manufactured on account of there applications in industry. Calcium oxide and sulphate are extensively employed in building and chemical industries Calcium phosphate, nitrate are useful as fertilizers Calcium carbide forms the source of acetylene which is an important starting material for the synthesis of many organic chemicals. A large number of calcium organic compounds find use in pharmacy. Calcium carbonate, CaCO3 forms a major constituent of the earths crust and occurs as massive beds of limestone, chalk and marble. It is found as dolomite in which a part of the calcium is replaced by magnesium. The term precipitated Calcium Carbonate applies to the commercial type of compound obtained by chemical means and distinguishes it from the material produced by mechanical treatment of natural varieties of Calcium carbonate such as calcite, marble, limestone and sea shells. Precipitated calcium carbonate is produced in a number of different grades which range in particle size from 9.03 to 15 micron I.P. grade precipitated calcium carbonate is used indentificers, foods, cosmetics, pharmaccuticals, and antibiotics. Technical grades are used as in ingredients in the manufacture of ceramics, putty, polishes, insecticides, inks, shoe dressings and as a filler in the production of adhesives, matches, linoleum and welding rods. Precipitated Calcium Carbonate is manufactured by passing carbon dioxide gas through a slurry of Calcium hydroxide milk of lime suspension. Calcium carbonate has the basic starting route as under follows. Limestone -> Qucik Lime -> Hydrated -> Lime -> Precipitated calcium Carbonate -> Activated Calcium Carbonate. The proposed unit is based on the production of precipitated Calcium Carbonate using the lime slurry (10% Calcium hydroxide solution and carbondixoide from the CO2 plant.