A thorough facilities design requires five steps to fully manage and handle the sand produced. Each step – from separation to disposal – must be integrated into the facility design to maintain hydrocarbon production and prevent flow interruption or equipment shutdown. A definition and purpose for each step helps to identify the equipment needed.
- Separate: to partition solid particles from liquid, gas, or multiphase flow to a separate stream. Unit processes include a hydrocyclone desander (liquid or multiphase), production separator, or filter.
- Collect: to gather partitioned solids into one central location and remove from process pressure and flow. This is accomplished using a hydrocyclone accumulator, vessel drain, or sump tank.
- Clean: to remove adsorbed hydrocarbon contaminants from sand particles using an attrition scrubbing system. This is an optional step, which is only used to treat sand for overboard discharge.
- Dewater: to remove free water from sand slurry to minimize the disposal volume. This can reduce the disposal volume by >90%. The simplest method involves a hanging mesh bag or screen lined bin.
- Transport: to bring solids to the disposal location. The design of the transport system depends on the facility location (subsea/onshore/offshore) and environmental requirements. Common options include overboard discharge, truck to landfill, ship-to-shore, and slurry injection.
- Rawlins, C.H. and Wang, I. 2000. Design and Installation of a Sand Separation and Handling System for a Gulf of Mexico Oil Production Facility. Paper 63041 presented at the SPE Annual Technical Conference and Exhibition. Dallas, Texas, 1-4 October.