However, it requires more equipment to purchase, install, and operate. This additional cost must be justified by the net benefit of the incremental liquid recovery; less the cost of natural gas shrinkage and loss of heating value, over that obtained from a cold-feed stabilizer.
Stabilizer with reflux and feed/bottoms heat exchanger.
At the top of the tower any intermediate components going out with the gas are condensed, separated, pumped back to the tower, and sprayed down on the top tray. This liquid is called “reflux,” and the two-phase separator that separates it from the gas is called a “reflux tank” or “reflux dram,” The reflux performs the same function as the cold feed in a coldfeed stabilizer. Cold liquids strip out the intermediate components from the gas as the gas rises.
The heat required at the reboiler depends upon the amount of cooling done in the condenser. The colder the condenser, the purer the product and the larger the percentage of the intermediate components that will be recovered in the separator and kept from going out with the gas. The hotter the bottoms, the greater the percentage of light components will be boiled out of the bottoms liquid and the lower the vapor pressure of the bottoms liquid.
A condensate stabilizer with reflux will recover more intermediate components from the gas than a cold-feed stabilizer. However, it requires more equipment to purchase, install, and operate. This additional cost must be justified by the net benefit of the incremental liquid recovery; less the cost of natural gas shrinkage and loss of heating value, over that obtained from a cold-feed stabilizer.