Application of Spray Cooling in Coal Gas Dry Recovery System of Blast Furnace
Abstract
The traditional coal gas dry recovery system is based on natural gas cooling method. It has low efficiency and large investment. In order to reduce the investment of blast furnace coal gas dry recovery system and improve the system efficiency, this paper puts forward a new cooling method, namely spray cooling method. It makes the cooling process change from natural gas cooling to spray cooling, which can effectively improve the recovery rate of gas, reduce energy consumption and reduce the investment of coal gas dry recovery system, and thus reduce the total cost of recovery.
Keywords:spray cooling, coal gas dry recovery, blast furnace, cost reduction
1 Introduction
As an important energy source to replace natural gas，Coal gas has been widely used in industry, especially for iron-making enterprises. Dry recovery of coal gas is an important means to capture a large amount of coal gas and convert it into energy. At present, the traditional recovery technology is based on the natural gas cooling method, which has low recovery efficiency and high investment. In order to reduce the investment of blast furnace coal gas dry recovery system and improve the system efficiency, in this paper, we propose a new cooling method -- spray cooling method.
2 Spray Cooling Technique
Spray cooling technology is a kind of heat transfer technology which makes full use of the heat and mass transfer of the sprayed liquid droplets. Compared with the traditional natural gas cooling method, spray cooling technology has the advantages of large cooling area, high heat and mass transfer efficiency and fast response speed. Therefore, it can effectively improve the recovery rate of gas, reduce energy consumption and reduce the investment of coal gas dry recovery system.
In the design and application of spray cooling system, the replacement of multiple heat transfer tubes can greatly reduce the space and cost of the equipment, and increase the system temperature and efficiency. At the same time, the spray cooling system takes into account the comprehensive benefits in terms of heat transfer surface, maintenance costs, energy consumption, system efficiency and recovery rate.
3 Application of Spray Cooling in Blast Furnace Coal Gas Dry Recovery System
The traditional blast furnace coal gas dry recovery system is based on natural gas cooling, which has low efficiency, large amount of heat dissipation equipment and high cost. The application of spray cooling technology in coal gas dry recovery system can solve the problem of large investment, high energy consumption and low recovery rate.
Firstly, because of the large heat transfer area and fast response speed, the spray cooling system can reduce the investment of heat exchange tube and increase the total cooling area, which can effectively improve the recovery rate of coal gas. On the one hand, the spray cooling method has a good cooling effect, the proportion of CNG recovered has increased, and the recovery rate of CNG is improved; on the other hand, the recovery rate of CNG can be improved by increasing the total cooling area, reducing the condensation pressure and improving the system efficiency.
Secondly, spray cooling takes into account the comprehensive benefits ranging from heat transfer surface, maintenance costs, energy consumption to system efficiency and recovery rate, reducing the investment and operating cost of the system.
Thirdly, spray cooling technology can bring more economic benefits to blast furnace enterprises, reducing production costs, improving the performance of enterprise products, and enhancing the ability of the enterprise.
4 Conclusion
In order to reduce the investment of blast furnace coal gas dry recovery system and improve the system efficiency, spray cooling method has been proposed in this paper. Compared with the traditional natural gas cooling method, spray cooling technology has the advantages of large cooling area, high heat and mass transfer efficiency and fast response speed, which can effectively improve the recovery rate of gas, reduce energy consumption and reduce the investment of coal gas dry recovery system. Therefore, spray cooling technology can bring more economic benefits to blast furnace enterprises, reducing production costs, improving the performance of enterprise products, and enhancing the ability of the enterprise.
