LPG fractions extraction

Application

Heavy hydrocarbons, emitted during preparation and/or processing of gas are not the final product.

Depending on using technology, they are like unstable condensate or wide spread of light hydrocarbons (WSLH) and are mixture of ethane, propane, butanes and heavier components. Fractional separation of these components and getting a final product of gas processing realized by rectification units. There is a sequence of rectification towers.

The sequence of rectification towers, quantity and parameters depends on quantity of final products. In simply case, rectification unit is made as one column – de-ethaniser, and derived product is mixture of propane and heavier components (WSLH).  The most high-demanded product of gas processing is propane-butane, that’s why the most popular configuration is chain deethanizer (WSLH product) - debutanizer (propane-butane and gas gasoline products). In case of processing significant volume of hydrocarbons in chain can appears depropanizer (propane product), deisobutanizer (n-butane and i-butane products), rectification towers of gas gasoline to obtain pentane, hexane and other fractions. 

Condensate stabilizer is special case of fractionation units. Scheme below is typical for facilities receiving three liquid products: propane, butanes and gas gasoline.