摘要 |
<p>A method and apparatus for protecting against the abrasion of pipe walls in a slurry pipeline caused by slack flow when the pipeline is operated in the batch mode, i.e., when one or more water batches and one or more slurry batches are transported through a pipeline. Pressure transducers sense the pressure at each relatively high point of the pipeline as an interface between a water batch and a following slurry batch passes that point. When one of the sensed pressures falls below a predetermined low value of pressure, a control device actuates valves to divert the flow downstream in the pipeline through a staged choke containing flow restrictors, thus raising the fluid pressure in the water batch which then counteracts the effect of the static head of the slurry batch. The flow is redirected away from the staged choke when one of the sensed pressures exceeds a predetermined high value of pressure, thus lowering the fluid pressure and preventing pipe wall overpressure.</p> |