Process for purifying biodiesel

Patent metadata

Field	Value
Publication number	US-2018094201-A1
Application number	US-201715723361-A
Country	US
Kind code	A1
Filing date	Oct 3, 2017
Priority date	Oct 4, 2016
Publication date	Apr 5, 2018
Grant date	—

Abstract

The present invention describes a process for purifying biodiesel without using a filter aid, in which purification of the biodiesel takes place by a sequence of washing operations after the reaction section, with stirring that is sufficiently vigorous to assist in the transformation of the molecules of esterified steryl glycosides, in order to convert them to a chemical form that can be removed by the process.

First claim

What is claimed is:

1 . Process for purifying biodiesel, comprising the following steps:
a) operations of washing of a stream of biodiesel followed by decanting; and b) filtration of a light phase resulting from a decanting operation, wherein the filtration is carried out in the absence of filter aids.

2 . Process for purifying biodiesel according to claim 1 , further comprising addition of a stream of dilute acid to the stream of biodiesel.

3 . Process for purifying biodiesel according to claim 2 , wherein dilute hydrochloric acid is used in the stream of dilute acid.

4 . Process for purifying biodiesel according to claim 1 , wherein the washing operation is carried out with stirring above 700 rpm and at a temperature in the range from 50° C. to 60° C.

5 . Process for purifying biodiesel according to claim 4 , wherein the washing operation is carried out with stirring above 800 rpm.

6 . Process for purifying biodiesel according to claim 2 , wherein the step of addition of acid is carried out before a first washing operation only.

7 . Process for purifying biodiesel according to claim 1 , wherein a first washing operation uses dilute glycerol, and has a residence time from 2 to 5 minutes.

8 . Process for purifying biodiesel according to claim 7 , wherein the dilute glycerol is produced in the actual plant of the biodiesel production process.

9 . Process for purifying biodiesel according to claim 1 characterized in that a light phase resulting from a decanting operations is cooled to a temperature in the range between 20° C. and 40° C. before it enters a further washing operation.

10 . Process for purifying biodiesel according to claim 1 , wherein a washing operation includes mixing an incoming stream with an amount of fresh water in an amount in the range between 2% and 6% of the weight of the light stream, and for a residence time in the range between 15 and 25 minutes.

11 . Process for purifying biodiesel according to claim 1 , wherein, before filtration of the light phase resulting from decanting, the light phase undergoes a process of drying and subsequent cooling to a temperature in the range from 15° C. to 25° C., and remains in this condition for a residence time between 3 and 14 hours.

12 . Process for purifying biodiesel according to claim 1 , wherein the filtration is carried out after the decanting operation and before any further additives are added to the light phase resulting from the decanting operation.

13 . Process for purifying biodiesel, comprising the following steps:
a) addition of a stream of dilute acid to a stream of biodiesel; b) an operation of washing of the stream of biodiesel followed by a first decanting operation, and further taking the light phase resulting from the first decanting operation and performing further washing and decanting operations; c) collecting dense phases resulting from the decanting operations, and recycling at least one dense phase to one of the washing operations; d) drying of the light phase resulting a final decanting operation; e) cooling of the light phase resulting from the drying step; f) filtration of the light phase resulting from the cooling step, in the absence of filter aids.

14 . Process for purifying biodiesel according to claim 13 , further comprising incorporation of additives to the product stream generated in the filtration.

15 . An apparatus for purifying biodiesel, comprising:
at least one washing vessel, for washing an incoming stream; at least one decanter, configured to split a stream into a heavy phase and a light phase; a filtration device for filtering a light phase produced by a final one of the at least one decanters, wherein the filtration device is configured to perform the filtration in the absence of filter aids.

16 . An apparatus for purifying biodiesel according to claim 15 , further comprising:
a dryer configured to receive the light phase produced by the final one of the at least one decanters.

17 . An apparatus for purifying biodiesel according to claim 16 , further comprising:
a cooler configured to receive the light phase from the dryer and to output it to the filtration device.

18 . An apparatus for purifying biodiesel according to claim 17 , wherein the cooler is configured to cool the light phase to a temperature in the range from 15° C. to 25° C.

19 . An apparatus for purifying biodiesel according to claim 18 , wherein the cooler has a residence time between 3 and 14 hours.

20 . An apparatus for purifying biodiesel according to claim 15 , wherein the apparatus has no inlets upstream of the filtration device for adding additives to the light phase produced by the final one of the at least one decanters

Assignees

• Petroleo Brasileiro Sa Petrobras

Inventors

• Vieira Jose Antonio Vidal
• XIMENES Vitor Loureiro
• Quintani Carolina Ludwig
• De Figueiredo Portilho Marcio
• Rangel Roberto Ricardo

Classifications

• B01D11/0446 Primary

  Juxtaposition of mixers-settlers · CPC title

• C10L1/026 Primary

  for compression ignition · CPC title

• B01D12/00

  Displacing liquid, e.g. from wet solids or from dispersions of liquids or from solids in liquids, by means of another liquid · CPC title

• C10L2290/547

  Filtration for separating fractions, components or impurities during preparation or upgrading of a fuel · CPC title

• C10L2290/545

  Washing, scrubbing, stripping, scavenging for separating fractions, components or impurities during preparation or upgrading of a fuel · CPC title