The invention discloses
environmental protection technology for bio-diesel production, which comprises the following units: 1)
raw material preparation; 2) pre-esterification; 3) fine esterification; 4) washing desulphurization esterification; 5) refined methyl ester separation; 6) low-temperature dewaxing; 7) emission
recovery; and 8)
wastewater treatment. The
environmental protection technology has the advantages that: 1. energy saving and emission reduction: the low temperature is served as technology heat and reduces the consumption of the energy; after the unit separation and purification, the produced
exhaust gas and waste liquid can be reused in the technology, thus reducing the
pollution emissions; 2. rapid esterification speed: high esterification rate; the hydrous
grease is separated promptly by a liquid separating tank, thus avoiding a reverse reaction and reducing the esterification time to 1 hour; the
acid value recovery problem is solved, so that the esterification is more thorough; the esterification rate can reach more than 98%; 3.output improving: the
environmental protection technology has compact technology and reasonable procedure and can realize continuous and large-scale flowing production; and 4. low bio-diesel solidifying point: the
wax in the bio-diesel is removed effectively by using a jacketed crystallizer and a full-automatic pressing filter, and the solidifying point is reduced.