基于虚拟仪器技术的饲料体外发酵产气自动记录系统的研制

Research and development of automated gas recording system for In Vitro fermentation based on virtual instrumentation

针对评定反刍动物饲料营养价值的常用体外发酵产气测试方法所存在的自动化程度低、测量误差大、工作效率低等技术方法不足，采用虚拟仪器技术设计了体外发酵产气自动记录系统。利用差压开关和电磁阀控制发酵容器内微气体压力，当压力上升至差压开关标定值时电磁阀导通并实现排气，每导通一次排出约1．0～2．8mL标定气体，通过记录产气次数完成产气量实时记录、分析和存储。试验结果表明该系统具有良好的自动化、智能化、图形化等特点，提高了实时测定结果的重复性、准确性和工作效率，降低了科研工作者的试验劳动强度。结合气体组分分析，该系统也可作为体外法评定饲料发酵温室气体（甲烷和二氧化碳）排放量估测的科学试验研究技术手段。

In order to solve the problem of low automaticity and high experimental error in the current feed nutrition evaluation approaches for ruminants, an automated gas production recording system for In Vitro fermentation based on virtual instrumentation was developed. The newly designed apparatus makes use of electronic pressure switch in combination with electromagnetic valves to release overpressure inside In Vitro fermentation container during the incubation. In this very sensitive system, no gas accumulation and pressure accumulation take place. Each vent of valve opening represents a certain amount of gas, set at about 1.0-2.8 mL. By recording the vents of valve openings in time, an In Vitro gas production can be recorded, analyzed and saved automatically. With satisfactory automation, intelligence and graphics as the experiment results show that the system has higher accuracy, higher repeatability and efficiency for the real-time test results, and can significantly reduce the workload of scientific researchers in feed evaluation. Through gas sample analysis, the system can be used for evaluation of greenhouse gas, such as methane and carbon dioxide, emitted by in vitro fermentation mainly by domestic ruminants.