NOVELTY - Improved method and process for commercial production of biodiesel or methyl ester as fuel or oleo-chemical feedstock, comprises: manufacturing biodiesel or methyl ester from refined vegetable oil by attaching specially designed low temperature and low pressure continuous biodiesel unit at vegetable oil refinery by linking pipelines from refined oil bulk storage tank (1) directly to first transesterification reactor (9); and using waste heat from existing refinery boilers and/or existing refinery thermal oil heaters by using heat exchanger (7) to supplement or totally supply heating energy.    USE - The process is useful for commercial production of biodiesel substitute for petroleum diesel or methyl ester as fuel or as a semi-processed feedstock for oleo-chemical feedstock.    ADVANTAGE - The method provides biodiesel or methyl ester: with continuous and absorbentless purification; and better oxidative stability compared to the product from conventional water washed process, hence cost effective. The method does not: need large area or site; new steam boiler plant; new balk storage tank to keep feedstock refined vegetable oil.    DETAILED DESCRIPTION - Improved method and process for commercial production of biodiesel or methyl ester as fuel or oleo-chemical feedstock, comprises: manufacturing biodiesel or methyl ester from refined vegetable oil by attaching a specially designed low temperature and low pressure continuous biodiesel unit at a vegetable oil refinery by linking pipelines from refined oil bulk storage tank (1) directly to first transesterification reactor (9); and using waste heat from existing refinery boilers and/or existing refinery thermal oil heaters by using heat exchanger (7) to supplement or totally supply heating energy needed for the biodiesel unit, where the temperature and flow of the heating oil is controlled and regulated by the biodiesel unit thermal oil heater (8).    DESCRIPTION OF DRAWING(S) - The figure shows the schematic representation of biodiesel unit.    Refined oil bulk storage tank (1)    Methoxide tank (2)    First transesterification reactor (9)    Heat exchanger (7)    Thermal oil heater. (8)