Thread Content
Shanxi Liheng Steel’s circulating water pumps achieve significant cost savings – Author/Source: Liheng Group, Date: 2019-06-28, Clicks: 6. Recently, the coking plant of Liheng Steel Company adopted a dual-drive energy-recycling technology for efficient operation; the circulating water pumps used in the chemical product pre-coolers were upgraded to dual-drive energy-recycling pump sets, resulting in a reduction of electricity consumption by around 50% for these pumps. As is well known, the power consumption of circulating water pumps in the coking industry often accounts for over 50% of the total electricity demand of coking plants, indicating significant room and potential for cost reduction. Previously, in order to reduce the electricity consumption of water pumps, the company’s coking plant adopted measures such as upgrading variable-frequency motors and using energy-efficient water pumps, but the power savings rate was usually less than 10%, resulting in unsatisfactory energy-saving effects. The total height of the primary cooler in the chemical production workshop of the coking plant is over 40 meters. Its main function is to use circulating cooling water to lower the temperature of coke oven gas, thereby reducing its volume and making it suitable for use by downstream users. To ensure effective cooling, the coking plant needs to operate 3 900-kilowatt pumps during the summer in order to meet the requirements of the production process. To further improve the energy-saving efficiency of the water pumps, after thorough investigation and verification, the company entered into an energy management contract with Tangshan Watt Company and utilized its patented technology to carry out technical upgrades on the circulation water pumps used in the chemical production cooling systems. It is understood that the dual-drive energy-recovery circulation pump set is a type of circulation water pumping system that utilizes hydraulic turbines to recover the excess pressure energy from the return water, and transfers this energy to the input shaft of the circulation water pump in a stable, timely, and complete manner through overrunning clutches. This approach helps to reduce motor energy consumption as well as water usage in the circulation system. It enables closed-loop recovery and reuse of part of the energy generated by the motor, resulting in a reduction of the average energy consumption per unit flow rate in the circulation water system by around 50%, as well as a reduction in water usage of about 2%. Previously, the coking plant had to operate 3 900-kilowatt pumps in order to achieve a circulation volume of 6,300 cubic meters per hour in the primary cooler ； After the modification, only one water pump needs to be turned on to increase the circulation volume to 8,000 cubic meters per hour. This not only meets the production requirements of the pre-cooler but also reduces power consumption by half, resulting in a very significant energy-saving effect.