Design And Development Of Computer Control System For Gas Mixing Process

The gas mixing process is an important part of utility system in iron and steel enterprises. The by-products in steel production such as blast furnace gas and coke oven gas, always serves as an important fuel source. Although the high yield of the blast furnace gas, it can't meet the demand of enterprises because of its low calorific value while coke oven gas has high calorific value but low yield. Considering the advantages and disadvantages of the two kinds of gas, So enterprises always mixed blast furnace gas and coke gas firstly ann then supplied to gas users.Efficent use of mixed gas have a great significance for energy saving,environmental protection and sustainable development.The gas mixing process control goal is to ensure the stability of the mixed gas calorific value and pressure. The gas mixing process is a complex process of strong interference and multivariate. It is difficult to achieve stable control of mixed gas calorific value and pressure through a single PID loop control.This Thesis is supported by the National Science and Technology Supporting Program (Advanced Control Technology of Whole production Line of Mineral Processing 2012BAF19G01) and the Key Automation Project (Synthetic Automation System of Newly Built 4 million t/a mineral processing plant),1. For the gas mixing process has strong interference and non-linear characteristics, this article propose a control strategy which based on such as feedforward compensation ratio and fuzzy control methods. And achieveing the simulation experiment of the control strategy in a laboratory environment, the results verify the control strategy is effect to the system control objectives.2. This paper describes the architecture, hardware design and software design of the gas mixing process computer control system. Hardware design includes networks of the system, instrumentation, control systems and other aspects; software design includes the functional design of control systems and monitoring systems.3. Based on the ControlLogix development platforms of Rockwell, and according to the control strategies and system functions of this paper, complete the development work of the computer control system. System development includes the overall network configuration, PC monitoring software development and control program development work. PC monitoring software is developed by the software of RSView32, which provides the operator with a friendly HMI; the control system programming is developed by the software of RSLogix5000.The system should be safe and reliable, in order to ensure that the system has capabilities of process or alarm which encountered during the operation of all the conditions.4. The gas mixing computer control system eventually is applied in the industrial field.Field operation shows that the system implemented process control requirements, verified the feasibility of the control strategy.