Testing of a well is very important. Well testing is to measure the amount of oil, gas and water produced from a well with in a specified time. Well test results gives lot of information about that well and also about the reservoir.
- Working of a test separator is almost similar to that of a bulk separator. Test separator is three phase separator. It separates the incoming well stream into oil, water and gas. The inlet stream first separates into gas and liquid. Gas pass through the mist extraction section and any entrained liquid particles will be removed there. Gas leaves the vessel through the exit nozzle under pressure control. Liquid which is a mixture of oil and gas falls to the bottom of the vessel.
- Here due to the difference in gravity oil particles moves upward and forms a different layer at the top. A baffle( weir plate) separates oil and water compartments. Oil which is light overflows the baffle plate and will be collected in the oil compartment. Water which is heavy stays at the bottom and will be collected in the water-boot, which gives enough time to separate oil completely. Oil and water leaves the separator on level control.
The purpose of the test separator is to separate the incoming stream of well fluids in to oil, water and gas and measure the amount of oil, water & gas produced with in a specified period of time.
To get the correct result from a well test we need to control pressure and levels and measure accurarely the amount of oil, water& gas produced.
Pressure is controlled by the PCV on gas outlet line. Pressure control is very important. If the pressure fluctuates then the test result will not be correct. The gas produced from the well is measured by a flow meter, usually one with a Daniel orifice meter. This allows the replacement of the orifice plate while the separator and gas line under pressure. Using the correct size orifice palte is a must to get accurate readings.
Water level is controlled by LCV-2. The amount of water produced is measured by a flowmeter.
Oil level is controlled by LCV-1. The amount of oil produced is also measured by another flow meter. The level controller for oil ( LCV-1) is usually works on gap control. This is used to give sufficient residence time for the oil to realease any trapped gas. Gas, oil and water produced is measured and totalised for the test period.