Managing Usage of Water in an Integrated Steel Plant...

Managing Usage of Water in an Integrated Steel Plant The important role that water plays in the production of iron and steel and also its value to the society is recognized by the steel plants. The assumption that fresh water is an inherently cheap commodity which is abundantly available and can be obtained with minimum of efforts is no more a valid assumption. The necessity of water conservation is increasing with each passing day. Hence it is necessary that steel plants take the management of the usage of water seriously and is to constantly evaluate how best to use water, finding improvements both in conservation and reuse. The extent of recycling of water which the steel plants are presently carrying out is varying very widely. While some plants are carrying out recycling of water to the extent of 98 % while in some other plant water is being used in many places in the plant by utilizing once through systems. In these plant the water discharged from the plant is very high. Water intake is more subject to control than is gross water use, being determined primarily by the extent of reuse. The lower limit for intake is the consumptive use of a plant, and the upper limit is the gross use. Both limits have been reached in the steel plants. In integrated plants, intake ranged from 5 cum per ton to 250 cum per ton of crude steel. Water can be reused and recycled. Hence any improvement in the efficiency of its usage as well as the reduction in its demand has an effect on the cost of production of steel. By increasing water recycling and cascading water use from higher to lower quality, integrated steel plants have been able to reduce their...

Water Management in a Steel Plant...

Water Management in a Steel Plant  Water is used in every shop of a steel plant and practically all the functions of water are utilized in the steel plant. Water is used in steel plant for process and heat transfer purposes; whereas water losses in the process are unavoidable (evaporation, drift), there is margin for further improving water use for the sake of the environment, energy efficiency, improvement of operations and for economic reasons. Use of water in a steel plant varied widely and is dependent on the availability of water, technologies employed, age and condition of the plants and equipment, kinds of the processes, and the plant operating procedures. Recycling of water also varies in a wide range in integrated steel plants.  Availability of water is one of the major factors in determining the rate of recycling. Water consumption in steel plant is mainly by evaporation, by spray from cooling towers, or by incorporation into a product. Various terms used in steel industry for water are as follows. Process water – It is the water that comes into contact with an end product or with materials incorporated into an end product. Cooling water – It is the water used exclusively for cooling purpose. Boiler feed water – It is the water introduced into boilers for conversion to steam Sanitary and service water – It is the water used for drinking, showers, general cleaning, and flushing of wastes. Intake water – It is the water which is pumped to the steel plant from water source. Make up water – It is the water added to the water system to compensate for the water losses. Recycle water – It is the water which is reused in a closed loop inside a water system often after...