(141a) Energy Optimisation in Natural Gas Processing Plant Using Reactive Distillation & Waste Heat Recovery from Flare Gas

In this paper two cases of energy optimisation are discussed. In first case, net gain is investigated for the method of reactive distillation in the Condensate Fractionation Unit (a distillation column) in a Natural Gas Processing plant, where in the hydrocracking catalyst is enclosed in a high porous envelope and it is submerged in the liquid on the plate and hydrogen is purged from bottom of plate so that cracking takes place. This leads to increase in the amount of lighter fractions (methane, ethane, propane, butane) which in turn decrease the amount of heavier fractions. As a result the load on Kerosene Recovery Unit (Products are Kerosene and low quality Diesel) is decreased and so is the energy consumption of the Kerosene Recovery Unit.

Apart from the obvious energy saving, we can in effect also save the necessity of an additional cracking unit.

In second case, we have designed a flow sheet to recover the waste heat from the flared gas in a Natural Gas Processing Plant by burning the flare gas(for a particular case of fixed composition of flare gas) in a special boiler which would produce steam and this steam in turn would rotate the turbine to generate electricity.