Biodieseltec

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1. The feedstock of vegetable oil is heated up to 55 – 60 °C in the preheat area of the plant. The oil enters the biodiesel production hall with a pump speed of 100 l/min and is transferred to one of the eight transesterfication tanks.
2. The transesterfication process needs vegetable oil and methanol together with a catalyst. The methanol consumption is 15 – 20 % during the transesterfication process. In the post processing after the sedimentation most of the unused methanol can be recycled. The total consumption for the biodiesel process is 10 % of methanol.
3. To start the transesterfication a catalyst is necessary. Normally NAOH or KOH is used with the amount of 3 – 6 kg per ton vegetable oil. The quantity depends of the amount of free fatty acids (FFA)
4. The methanol and the catalyst are mixed in the methoxid mixing tank. Intensive mixing is necessary. Dissolving the catalyst in the methanol generates an exothermic reaction and the temperature has to keep below 55 °C.
5. After complete dissolving of the catalyst the methoxid is pumped to the methoxid buffer tank.
6. Each transesterfication reactor need 200 l methoxid every tow hours. All eight reactors have a consumption of 800 liter methoxid per hour. A tank with 5 m³ give a buffer time of 6 hours and 10 m³ is adequate for 12 hours.
7. The optimal process temperature is a little bit lower than the evaporating temperature of the methanol (63 °C). The methoxid is heated up to 55 °C in the methoxid preheating tank.
8. Hot water with 55 – 58 °C is transferred from the central heating system inside the methoxid preheating tank.
9. Each reactor is filled with 1000 liter oil.
10. After filling up with oil the methoxid with an amount of 150 - 180 liter is pumped to each reactor.
11. The next table shows the time consumption of the transesterfication process in 8 steps. In total the complete process need 2 hours. With eight reactors the production capacity is 4000 liter per hour or 96.000 liter per 24 hours a day.

    Step 1:	Filling with 1000 liter oil	11 min
    Step 2:	Filling with 150 liter methoxid	4 min
    Step 3:	Mixing and circulation	40 min
    Step 4:	Sedimentation of glycerine	30 min
    Step 5:	Draining 80 % of the glycerine and the first part of the transesterfication process is ready	2 min
    Step 6:	Adding 20 – 30 liter methoxid to start the second part of the transesterfication	1 min
    Step 7:	Mixing and circulation	20 min
    Step 8:	Draining the crude biodiesel to one of four sedimentation tanks and waiting for the next cycle start	12 min

12. The crude glycerine of the first process step and is pumped to the glycerine storage tank.
13. The crude biodiesel is pumped to one of the four sedimentation tanks.

    Step 1:	10 hours filling time for 40 m³
    Step 2:	10 hour sedimentation time
    Step 3:	Additional sedimentation time of 10 hours
    Step 4:	Draining to methanol distillation

14. Pump crude biodiesel to vacuum distillation system.
15. The biodiesel is heated up to 70 °C and sprayed inside the Vacuum distillation tank. The methanol evaporates at 63 °C.
16. Clean biodiesel and free of methanol is pumped to the dry-wash system.
18. The evaporated methanol is condensed inside the methanol condenser.
19. The condensed methanol is pumped out of the condenser.
20. Recovered methanol is reused for the transesterfication process.
21. The biodiesel has small amounts of glycerine. This are removed inside the dry-wash system. The special adsorbent material adsorbs glycerine. The biodiesel runs through two columns. The third column is used for recycling. In the first column the main part of the glycerine is adsorbs.
22. The second column adsorbs the last amount of glycerine.
23. The third column is for the recycling process and runs normally after 50 - 100 hours of operation. After this period of time the adsorbent is full and has to be recycled. The recovery of the adsorbent is done with methanol and its removes the glycerine. The life time of the adsorbent is more than 5 years. All recycled liquid with methanol, glycerine and biodiesel is pumped to the recycling tank.
24. The dry-washed biodiesel runs after the first column into a buffer tank with 2.000 liter volume.
25. Then the biodiesel is pumped to the second column for the second dry-wash step with the cleaner adsorbent material. If the column one is full, then this column 2 turns to column one. With this principle always the optimum of purification is possible.
26. Dry-washed biodiesel is stored and buffered in a 10 m³ tank.
27. The biodiesel is pumped with a maximum pressure of 4 bars through the filter system.
28. At the end of the biodiesel production process the finest particles has to be filtered out. A filter system uses first the bag filter with a pore size of 1 my.
29. The smallest particles are filtered with the candle filter. The pore size is 1 my. This second filter system has six candles with the length of 1 m.
30. In winter time the biodiesel has to mix with winter additives. The additive mixer combines a static mixer together with a mixing tank. Also other additives can be added.
31. Now the biodiesel is ready for quality control and storage in the outside tank farm.
32. The recycled liquid from the dry-wash system is stored in a 10 m³ tank. This is a mixture of biodiesel, methanol and glycerine.
33. The mixture of waste of the dry-wash system is transferred back to the transesterfication process in the concentration of 2 - 5 %. There the glycerine is separated in the normal way of sedimentation.
34. Glycerine from the sedimentations tanks is pumped to the crude glycerine tank.