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...

Water Management and Pollution Control in Steel Plant Sep04

Water Management and Pollution Control in Steel Plant...

Water Management and Pollution Control in Steel Plant An integrated steel plant incorporates a number of processes right from raw material preparation to rolling of finish steel. All these processes need water. When the water is used in these processes it gets contaminated with pollutants in various amounts and concentrations. Typical requirement of water in various processes in steel plant needs 100 to 200 Cum per ton of steel. Pumping capacities for this amount of water is needed in the steel plant. The requirement of makeup water depends on the water treatment and recirculation facilities in the plant and usually is in the range of 2 to 4 Cum per ton of steel. Water management in an integrated steel plant is very important for its successful operation since the integrated steel plant needs a large amount of water for its operation. During the operation of the plant this water gets polluted. It is very difficult to separate water pollution control from water management in the plant. A good water management leads to a decrease in pollution control of water while at the same time pollution control of water needs good water management.  Good water management requires zero or minimum water discharge from the plant. This is achieved by incorporating elaborate water treatment systems for recirculation of water. This reduces water consumption since there is a reduction in the requirement of makeup water. It also reduces the water pollution since the water discharge from the plant boundary becomes nil or negligible.  Further it reduces the necessity and cost of treatment of polluted water before its discharge from the plant boundary. Use of water Water has many varied uses in the iron and steel plant and the quality of water needed for each use also vary....