The distillers are towers with structured packing to fractionate heavy and light boiling impurities and to ensure that the methylesters are distilled at the lowest possible temperature.
Squeezing of the residue is carried out in a separate distiller.
Condensation can be carried out inside the tower over packing with cooling of an external pump around or outside the tower in shell and tubes condensers.
In both cases heat is recovered generating low pressure steam.
Canned pumps with falling film reboilers or centrifugal pumps with suppressed vaporisation reboilers are proposed according to the case.
Glycerine distillation/ refining
The distillation is based on a packed tower where the glycerine is distilled, fractionated to separate both heavy and light boiling impurities and condensed.
Yellowish glycerine is condensed in a separate scrubber. Deodorisation can be supplied according to the material being processed. Refining is continuous on three in line bleachers. In case of spent lyes or bio-diesel glycerine a salt squeezing section is added.
High acidity feedstock esterification with glycerol: a cheap feedstock for biodiesel producers
Following the biodiesel market developments and the increasing request from biodiesel producers for cheap feedstock, Desmet Ballestra has developed an esterification technology enabling to process a wide range of high acidity feedstock, such as fatty acids distillate and acid oleins with desalted concentrated glycerol obtaining a neutral esterified oil suitable for biodiesel production and for power generation.
The installation of an esterification with glycerol plant provides as key advantage the production of a cheaper biodiesel, which becomes particularly attractive thanks to the “double counting mechanism” which is/will become applicable in several countries.
Methylester Cold Clarification
During storage in tank farm, methyl ester final product quality could be negatively affected by the presence of some contaminants, already contained in the raw material fed to biodiesel plant. These components, identified mainly to be sterol glucosides, causes precipitation problems (e.g., accumulation in downstream equipment of production line, filter plugging in diesel engine) when stored for a certain time at ambient temperature.
The Desmet Ballestra Methyl Ester Cold Clarification Unit is designed to reduce the biodiesel Total Contamination in order to meet standard specification requirement (except of cold test CFPP and other parameters depending on feedstock and not influenced by transesterification process).
This technology allows removing the haze and decreasing contaminant quantity without using washing water for centrifugal separation minimizing the waste water effluents.
The glycerine purification unit is designed to process the raw glycerine coming from the upstream units in order to neutralize the residual catalyst and split the soaps formed during transesterification side reactions.
The fatty acids derived from soap splitting are sent to storage (or unit 6191 if included) as by-product of biodiesel plant while the purified glycerine is sent to downstream glycerine concentration (unit 6166C).
The Desmet Ballestra Glycerine Purification Unit is essential to maximize the removal of soaps and sodium methylate from the raw glycerine in order to be suitable for the downstream distillation process.
The purification technology allows a very easy operational management by proposing in sequence four process steps: methanol removal by flashing, soaps acidification reaction, olein separation and glycerine neutralization.