TECHNOLOGY IN DETAIL
Under the effect of HCl gas, glycerine with a proper purity is chlorinated and in an aqueous solution transformed into monochlorohydrin (MCH) and then into dichlorohydrin (DCH). The formation of epichlorohydrin requires only DCH. Via azeotropic distillation the DCH and water is separated on the top of the column and fed into the saponification unit. On the bottom of the column the remaining mixture of MCH and not reacted glycerine is fed back into the reactor and is chlorinated again.
download EPIPROVIT flow diagram
The saponification of DCH, its transformation into epichlorohydrin, is done by addition of sodium hydroxide (NaOH). The resulting mixture of epichlorohydrin and remaining DCH traces, as well as water and salt (NaCl), is separated by rectification. While epichlorohydrin in an aqueous solution is transferred to the next rectification step and separated from water, the remaining salt-water mixture containing residuals is fed into the post-saponification unit. The aqueous epichlorohydrin is rectified and purified from water and organic residues. The resulting brine is treated in a KVT-developed and patented brine treatment plant.
The final rectification, which separates water and residues from the end product, ensures high purity epichlorohydrin.
The off-gas as well as the residuals from the rectification unit are efficiently treated in the integrated combustion unit.
The energy content of the excess hydrogen from the glycerine chlorination is used effectively for the combustion. The resulting brine from the saponification unit is properly treated in the brine treatment plant and recycled for the chlorine-alkali electrolysis.
- In comparison with propylene-based technology, the EPIPROVIT process shows a significant reduction in by-products e.g. during the saponification step the formation of calcium chloride is completely avoided.
- Compared to similar technologies the wastewater (brine) containing production residuals is nearly free of AOX (traces <0,1 ppm). The brine is purified with the integrated KVT brine treatment plant. The pure brine can be recycled into the chlorine-alkali-electrolysis plant, which results in reduced operating costs.
- Normally the excess of hydrogen (H2) during the chlorination step needs to be separated in complicated ways. With EPIPROVIT this step is avoided. The excess of H2 is treated in the integrated combustion unit that requires a lower quantity of natural gas. The energy content of the combustion gases is efficiently recycled into the epichlorohydrin production process as steam.
- The EPIPROVIT energy management is optimized ensuring higher efficiency and lower energy consumption in comparison with the propylene-based process. The combustion unit uses the innovative KVT TARDIGRAD catalyst which works at lower temperatures than conventional catalysts.
Our customers include:
Our customers include:
- Epoxy resins producers
- Epichlorohydrin producers by propylene
- Chlorine/HCl producers
- Biodiesel/Glycerine producers