Scope
These methods are described to obtain a homogeneous liquid hydrocarbon samples for laboratory analysis In this method does not recommend placement of the sampling point.
An outline of the method
A sample of liquid hydrocarbon transferred under pressure from the existing piston in the cylinder. The piston cylinder is designed to put the pressurized inert gas. Piston also serves as a barrier between the inert gas and the sample, so that at the time the samples were pressurized liquid inside, there is no empty space that can be used for the evaporation process (expansion) of samples.
Equipment
1) The container as shown in Figure 11, which consists of metal tubing that has been refined inside as well as outside, is designed cylinders can withstand the maximum pressure at the time of sampling and resistant to corrosion. The volume of the cylinder depending on the sample volume required.
2) Cylinders containing movable piston and piston rings fitted made of TFE (Tetra Fluoro Carbon). The piston rings must be resistant to the presence of the sample.
3) transfer pipe, valve and pressure gauge (manometer)
Figure 11 Floating Piston Cylinder
Sampling procedures
This procedure is used to sample a liquid hydrocarbon liquid.
– Fill the cylinder with the inert gas through the shellfish D until the pressure in the cylinder reaches approximately 10 psi above the pressure of the sample at the sample point, and then close the shellfish D.
– Connect with a sampling piston cylinder, closed shellfish B and C, do purging the sampling pipe flow into the cylinder by opening shellfish B slowly. Then change the direction of flow into the cylinder by opening shellfish C leading to the cylinder slowly closed shellfish B, while observing the pressure on the manometer at the other end of the cylinder.
– Open shellfish C input samples to the brim while removing the inner gas by opening shellfish D slowly toward the inner gas cylinders.
– Make sure all inert gas present in the sample cylinder was out and replaced with liquid hydrocarbons, (note the pressure on the manometer keep not to go down), cylindrical samples have now been filled to 80% due to the reduced volume of the piston.
– Then close all shellfish and remove the cylinder from the source of the samples and inert gas cylinders.
– Samples were prepared for analysis.