Fig. 7-Flow curve of system under inclined tube condition
3.4 Flow characteristics of hydrate slurry under shutdown and restart conditions. In order to simulate the working condition of shutdown and restart in the actual pipeline, the phenomenon is simulated by shutdown and restarting the pump during the experiment. In addition, the influence of polymer inhibitor on the flow characteristics of pipeline shutdown and restart was also explored. The Fig.8shows the slurry flow curve in the loop shutdown restart system with and without Anti-agglomerants agent. The two systems shut down the pump at5min after cooling, and start the pump again at5min. In the system without Anti-agglomerants agent, the flow rate of hydrate slurry drops to 0 automatically after 7 minutes of operation. In the system with 0.5 wt % Anti-agglomerants agent, the hydrate slurry can still flow smoothly after 7 minutes of restart, and the flow rate is reduced to 0 by manually shutting down the pump. Although the flow rate can not return to normal after the second shutdown, the new Anti-agglomerants agent can ensure that the flow time of hydrate slurry is longer than that of pure water system after the first shutdown and restart. The flow rate of the system with Anti-agglomerants agent fluctuates greatly, and the flow rate is 0 after the initial restart. The reason has been mentioned in the above.