Process and plant for producing hydrocarbons

1. A process for producing hydrocarbons from fatty acid esters contained in fats or fat oils, wherein the fatty acid esters are split up by hydrolytic decomposition into a first stream containing crude alcohol and water and a second stream containing free fatty acids, and wherein the free fatty acids of the second stream are hydrogenated with a suitable hydrogenating agent to obtain saturated hydrocarbons.

2. The process according to claim 1 , wherein the crude alcohol is glycerol.

3. The process according to claim 1 , wherein the separation into a first stream and a second stream is effected by liquid-liquid phase separation.

4. The process according to claim 2 , wherein the first stream is evaporated to a glycerol concentration of >80 wt-%

5. The process according to claim 4 , wherein the water obtained during evaporation is recirculated to the hydrolysis.

6. The process according to claim 4 , wherein the glycerol is cleaned up by distillation to a concentration of >95 wt-%.

7. The process according to claim 1 , wherein before hydrogenation the second stream is separated into a third stream containing the fatty acids and a fourth stream containing impurities.

8. The process according to claim 7 , wherein the separation into the third and fourth streams is effected by distillation or rectification.

9. The process according to claim 7 , wherein the third stream is hydrogenated with hydrogen to obtain saturated hydrocarbons.

10. The process according to claim 1 wherein the hydrogenation is effected in the presence of a hydrogenation catalyst.

11. The process according to claim 1 wherein the saturated hydrocarbons are at least partly isomerized to isoparaffins.

12. The process according to claim 7 wherein the fourth stream containing impurities is partly recirculated to the hydrolysis reactor.