This is a process for converting free fatty acids (FFA) into triglycerides and some amount of diglycerides.  For this glycerine is added to the oil to the extent of about 4% of the FFA weight.  The FFA as well as 40% of the glycerine added is then converted into oil through esterification.  The FFA that would sell for Rs 26/kg is then converted into oil that would sell for Rs 42/kg, at the cost of some capital equipment and 4% of glycerine at Rs 26/kg.

No catalyst is required in this process.  Any FFA escaping is fed back into the system.  It can be used for biodiesel to improve the profitability of the plant.