规模化猪舍废气复合净化系统设计与试验

为解决规模化猪舍废气排放造成的环境污染问题，设计了一种猪舍废气复合净化系统。该系统采用化学法与水洗法相结合，通过PLC（可编程逻辑控制器）控制系统实时采集净化系统内的pH值、电导率、液位和压差等动态环境数据，智能控制洗涤泵启停和电磁阀通断，自动完成供水、加酸、喷淋和排废4个工作环节。同时，控制系统采用MCGS触摸屏与PLC建立通讯，通过创建人机交互界面实现系统环境数据监测、运行状态流动显示、按需配置系统参数和报警信息输出等多种功能，实现了系统操作的人性化和过程的可视化。系统可根据实际应用中对净化效率和运行成本的要求，实现多种控制模式，均有效抑制了猪舍废气排放。试验结果表明，系统对主要污染成分氨气的平均去除率可达到85%，整体运行可靠、控制简单，经济成本量化清晰。该系统在江西某种猪场实施应用，成效显著，可为畜禽养殖环境废气净化处理的工程应用提供参考。

Design and Experiment of Combination Air Scrubbing System for Large-scale Pig House

An air scrubbing system was developed to efficiently treat the exhaust emission from large scale pig house. The system utilized a combined scrubbing system that involved chemical method and water washing method. The real time dynamic environmental data, including pH value, EC value, liquid level and differential pressure were collected. The intelligent control strategy was established via programmable logic controller (PLC) control system to regulate the start up of the washing pump and electron magnetic valve. In this manner, four work links: water supply, acid addition, spraying and waste emission were conducted automatically. At the mean time, the control system utilized MCGS touch screen to establish communication connection with PLC. In particular, the human machine interface was created to realize the monitor of system environmental data, dynamic display of operation process, configure system parameters, system alarm and other functions needed. Therefore, the system achieved the purpose of monitoring and controlling on the whole purification process, as well as satisfied the simple operation of system and visualization of the whole scrubbing process. Moreover, the system can also implement a variety of control modes according to the requirements of efficiency and economy in practical applications. It was found that all control modes were able to inhibit the emission of pig house effectively. The experimental results indicated that the removal rate of ammonia gas can reach 85%. The overall system was entirely well operated and easily controlled, and the economic costs were clearly quantified as well. This gas scrubbing system was successfully applied to a pig breeding farm in Jiangxi Province, which provided significant reference of air scrubbing techniques for livestock operations in practical engineering.