Circored and Circofer processes of ironmaking Feb24

Circored and Circofer processes of ironmaking...

Circored and Circofer processes of ironmaking Circored and Circofer processes of ironmaking are fluidized bed based iron ore fines reduction processes. These processes completely avoid agglomeration process and make direct use of iron ore fines. Since the processes use non coking coal, necessity of coke oven battery is not there. Fluidized bed technology is ideally suited to energy-intensive processes like direct reduction because it enables high heat and mass transfer rates. Both the Circored and the Circofer processes have been developed by Lurgi Metallurgie GmbH, Germany (now Outotec Oyj, Finland) for the production of direct reduced iron (DRI) from iron ore fines. For both processes, capacities above 1 million tons per annum are possible in a single production unit, resulting in improved economies of scale. Circored process is hydrogen (H2) based process while the Circofer process is coal based. Circored has a two-stage configuration in order to achieve a high metallization of 90 % to 95 %, whereas Circofer has a single-stage configuration which can achieve pre-reduction up to a metallization of around 70 %. Circofer coal-based process produces pre-reduced feed material for smelting reduction reactors, such as AusIron, or electric smelting furnaces – the final product being hot metal or pig iron. Circored process Circored process uses fluidized beds on a scale adopted by Outotec for other applications. Development of the process was initiated in the late 1970s with the pilot plant tests conducted at the ELRED plant of ASEA in Sweden. Tests were also carried out in the 3 tons per hour CFB reactor demonstration unit at Thyssen Stahl in Duisburg, Germany. These tests had focused on the treatment of steel plant wastes. The first commercial Circored unit was built in 1998 by Cliffs and Associates Ltd. at Point Lisas Industrial Complex...

Basics of Steam Boiler Feb22

Basics of Steam Boiler...

Basics of Steam Boiler A steam boiler is an enclosed container where water is heated under controlled conditions to convert it into steam. Boiler is basically a heat exchanger where heat is transferred to water. It is also sometimes referred to steam generator. Thermal energy for heating water is supplied either by fuel (Gas, liquid or solid) or by waste energy available from various industrial processes. Sometimes solar energy is also used for the production of steam. Steam produced in a boiler can be low pressure, medium pressure or high pressure.  In an industrial context, the steam produced is used as process steam in various industrial processes or for driving turbines for the production of electricity. Every boiler is designed to transfer as much thermal energy as possible to the water contained in the boiler. Heat energy is transferred by conduction, convection and radiation. The relative percentage of each is dependent upon the type of boiler, the designed heat transfer surface and the fuels that power the combustion. There are mainly two types of boilers. They are fire tube boiler and water tube boiler. Fire tube boiler consists of numbers of tubes through which hot gasses are passed. These hot gas tubes are immersed into water, in a closed vessel. In this boiler one closed vessel or shell contains water, through which hot gas tubes are passed. These hot gas tubes heat up the water and convert the water into steam and the steam remains in same vessel.  Fire tube boilers are generally used for relatively small steam capacities and low to medium steam pressures. These boilers are compact, of packaged construction and cheaper. Water tube boiler is a kind of boiler where the water is heated inside tubes and the hot gasses surround...