The experimental system of gas hydrates integrative simulation and its control module

Abstract

The Experimental System of Gas Hydrates Integrative Simulation (ESGHIS) was built to study the thermodynamics and kinetics of gas hydrates formation and dissociation, distribution characteristics of temperature and pressure in gas hydrate well drilled for exploration and exploitation, and gas hydrate drilling technologies. A control module was developed to lighten labor intensity and guarantee experiment safety in the ESGHIS. A multi-function card PCI-1711 was selected as the core of the control module, which has high-speed data acquisition and digital/analog output. A relay OMRON/G2R-1 was used to automatically manage the startup/stop of units. A solenoid valve VP542 and a gas-control valve NV1-20-6M-ATC were used to operate overpressure protection. PLC TEMI550 was used to control programmable high-low temperature test chamber HLT705P through connecting it to a computer using a RS232/RS485 converter I-7520. A proportional valve and a stepper motor were used to control lifting and rotary speed of the drilling pipe in minidrilling module. The corresponding software was coded by using multithreading and Visual C++6.0 language. It had good quality on interface, maintainability and expansibility. The whole module was operated successfully in the experiments of gas hydrates formation and mini-drilling simulation. It worked steadily, executed quickly and had high sensitivity for overpressure protection, which largely lightens the experimental intensity of the labor and enhances the safety of the experiments.