Biodiesel and Glycerine Distillation

Biodiesel Distillation

When producing Biodiesel from waste products, we cannot always guarantee that the end product will meet the EN14214 specification using our standard equipment. This is not because of our process, it is simply a reality with some low quality feedstock.

But this does not mean that the Biodiesel standard cannot be achieved. IncBio has partnered with a worldwide leader in the manufacture of short path wiped film evaporators, and as such we are now able to offer highly efficient and cost effective Biodiesel distillation columns, which are able to ensure that the Biodiesel produced will not only consistently meet the standards, but also exceed them, meaning that even as the standards get ever stricter, our Biodiesel plants are always able to adapt to the new requirements and be at the forefront of quality Biodiesel production.

Whether the problem is unreacted mono, di and triglycerides, polymerised triglycerides, or failure to meet the ASTM 6751 cold soak filtration test, our Biodiesel distillation columns are certain to resolve it.

Glycerine Distillation

The main by-product of Biodiesel production is glycerine. With the significant uptake of Biodiesel production seen in recent years, the marketplace has been flooded with this crude glycerine (approximately 80% purity). Initially this crude product could fetch decent prices in the market, but this is not the case anymore, currently only negligible prices are offered. But this by-product’s revenue generating potential should not be ignored.

It amounts to approximately 10% of the total Biodiesel produced, and with further refinement it can become a valuable addition to a Biodiesel plant’s profits. Additionally if it is not refined, this form of glycerine must either be disposed of to landfill, or be sold off to market for a minimal amount due to the water, soap and salt content.

The price volatility of glycerine, primarily caused by biodiesel production, has resulted in massive changes in the glycerine refining sector.  The demand for refined glycerine, technical grade and higher, has risen and is starting to stabilize. This is why IncBio has focused on providing glycerine refinement equipment, helping biodiesel plants turn a profit with their finished glycerine, whilst avoiding high disposal fees or negligible returns from their crude glycerine.

By refining their glycerine to >97% purity, plants can now sell off their glycerine for a much higher return and create a new and very important revenue stream for their plant.

Refining glycerine to technical grade brings the following advantages to a biodiesel plant:

• It makes the environmental permitting process much easier, by significantly reducing the waste stream


• It considerably reduces the costs of waste disposal to landfill


• It creates an additional revenue stream for the plant

Glycerol distillation technology

GLYCERINE DISTILLATION

Technical & pharmaceutical grade glycerine can be produced starting from a wide range of natural feedstocks, mainly by-products of industrial processes for the production of soap (spentlyes), fatty acids (sweetwaters) or methylesters (biodiesel glycerine).
Andreotti Impianti Spa developed a proprietary technology for pharmaceutical glycerine production, will plants configurations best suited for each specific raw material.


REFINED GLYCERINE PRODUCTION STEPS

Typically, refined glycerine to EUP/USP XXIII standards is obtained through the following technological steps:

• Sweetwaters or spent lyes purification


• Sweetwaters or spentlyes concentration to respectively 88 or 80% glycerol content.


• Crude glycerine distillation, bleaching and deodorizing.

It is to be noted that crude glycerine coming from our transesterification plants for biodiesel production (with average glycerol content of 80 - 85%) can be sent directly to distillation making away with any prior dilution, purification and concentration steps.
Several purification steps can be combined in order to maximize process yields using lowest quantity of chemicals.
Special care is devoted to avoid ambient pollution, by providing those units with high efficiency air scrubbing system, and reducing to a minimum liquid and solid by-products sent to disposal or to treatment.
In case of crude glycerine deriving from fat splitting or saponification, one unit of water evaporation, typically double effect with energy saving system, is provided to concentrate the distillation unit feed up to residual water content of 5-15%.
Single step distillation units have been developed by us over the years by a continuous updating of proprietary technology. Today ANDREOTTI IMPIANTI offers plants that combine best specific utilities consumptions and maximum flexibility on process parameters adjustment referred to variation of feed composition.
As disposal of various by-products and air / water pollution is the biggest problem to be solved today in industrial plants, ANDREOTTI IMPIANTI has included in its plants special pitches stripping units, that help minimize the environmental impact.

 

ANDREOTTI IMPIANTI'S GLYCERINE TECHNOLOGY HIGHLIGHTS

• Multi-feedstock plant, fully continuous


• Ease of operation thanks to completely automated control


• Low consumption due to high recovery rate


• Highest environment compatibility thanks to extremely reduced effluent emissions


• Low installation and operational costs


• Liquid-liquid glycerine distillation


• Single-column glycerine distillation


• Peculiar continuous residues stripping system, with possibility to obtain liquid or dry residues


• Continuous bleaching / purification by activated carbon


• Extremely low esters content in refined glycerine


• Increased refined glycerine yield thanks to the use of self generated low pressure steam

Glycerine Distillation and Refining

Glycerine Spent Lyes Pretreatment

Glycerine content of fat hydrolysis wastewater and manufacturing waste water reaches about 10-15%. Generally adopting methods of chemical decontamination, ion exchange and electrical purification.

Spent Lyes Concentration

Based on the principle of evaporation, content of glycerine reaches 80-90%, to yield crude glycerin.

Glycerine Distillation and Refining

Crude glycerine is distilled in distillation column to make refined glycerine, after decolorizing and bleaching to make finished products refined glycerin. Mixed vapour out of the top of distillation column is further separated into 2nd grade glycerine.

Fatty Acid Distillation

Natural fatty acids can be extracted from animal oil, palm oil, palm kernel oil and coconut oil. Main products include mixed fatty acid, crude oleic acid, crude linoleic acid, crude stearic acid, hydrogenated stearic acid, palmitic acid and etc.

Oil and Fat Pretreatment

Pretreatment is designed to remove impurities. Whether pre-treat or not depends on the content of pectin, wax and other harmful substance except triacylglycerol when using vegetable oil as raw materials to produce fatty acids. Common pretreatment process includes hydration degumming and bleaching. Phospholipids can be removed by means of adding a small amount of phosphoric acid and the remaining impurities will be removed under the adsorption of bleaching carclazyte.

Oil and Fat Hydrogenation

Oil and hydrogen react at a certain pressure and temperature, in order to reduce the unsaturation of oil. The hydrogenated oil will yield more stable products in the further processing including catalyst filtration and avoid the fatty acids hydrogenation step.

Oil and Fat Splitting

Adopting non-catalytic countercurrent hydrolysis at high pressure and temperature, oil splitting into fatty acid and glycerol. This method has the feature of high hydrolytic degree.

Sweetwater Pretreatment

Chemical treatment of spent lyes, on the contrary of sweet water, is unavoidable and is carried out in a continuous, fully automatically controlled unit.

Sweetwater Concentration

Based on the principle of evaporation, content of glycerine reaches 80-90%, to yield crude glycerin.

Glycerine Distillation and Refining

Distillation is based on a packed tower where glycerine is distilled, fractionated to separate both heavy and light boiling impurities and condensed.

Fatty Acids Distillation

Distillation tower is equipped with structured packing to fractionate heavy and light boiling impurities and to ensure that fatty acids are distilled at the lowest possible temperature. Condensation can be carried out inside tower over packing with cooling of an external pump around or outside the tower in shell and tubes condensers.

Fatty Acids Fractional Distillation

According to different boiling points of different fatty acids at the same pressure, separate mixed fatty acids of different carbon chain to meet product demand.

Fatty Acids Hydrogenation

Fatty acids mixed with catalyst, entering into hydrogenation tower, then analyze the iodine value of product to determine whether the hydrogenation is completed.