基于PLC和组态软件构建沼气发酵控制系统

Building control system of biogas fermentation based on PLC and force control

根据沼气干发酵工艺流程和控制要求,提出了基于PLC和组态软件的沼气发酵自动控制系统。该系统能够实现鄂尔多斯示范工程沼气发酵生产过程的实时监控和自动控制。系统能够利用组态软件KingView6.55在沼气发酵系统中完成数据的上传下达、组态的开发、功能的分析、监控画面的建立、计算机与PLC的通讯,实现沼气发酵过程的高产气率和设备的稳定运行。针对鄂尔多斯示范工程中有效容积为300 m3的立式厌氧发酵罐及整套工艺设备进行了调试与运行,结果表明:在该系统自动控制下,21 d后发酵过程达到了稳定状态,沼气日产气量达到360 m3,且沼气中甲烷含量达到56%以上。

According to biogas dry fermentation technological process and control requirements, the automatic control system of the organic raw materials of biogas fermentation was proposed based on PLC and force control. The system can realize the real-time monitoring and automatic control for the fermenting production process of Ordos demonstration project. The system can complete the data transmission, the development of force control, the functional analysis, the establishment of monitor screen, the communication between computer and PLC based on King View6.55 in biogas fermentation system, and it had realized the high gas production rate and stable operation equipment in the biogas fermentation process. Finally, vertical anaerobic fermentation tank, which effective volume is 300 m3 and a complete set of processing equipment were debugged and run in the Ordos demonstration project.Therefore, the results show that fermentation process of the control system can achieve stable operation after 21 days, and daily biogas yields of 360 m3 and CH4content of above 56% were obtained under the system automatic control.