Efficient Conversion of Wheat Starch into Bioethanol Using the Low Energy Intensive STARGEN Technology

Transcription

1 Efficient Conversion of Wheat Starch into Bioethanol Using the Low Energy Intensive STARGEN Technology 4 th European Bioethanol Technology Meeting Detmold April 15-16, 200

2 Topic Introduction to STARGEN STARGEN process for whole grains Why Processing Wheat Starch Considerations when Processing Wheat Starch STARGEN process for (wheat) starch Conclusions

3 Introduction STARGEN Optimized blend of amylases to hydrolyze raw (granular) starch Produces glucose from uncooked grains during yeast fermentation Superior performance in SSF of dry milled grains without cooking Available in two versions STARGEN 001 for the conversion of corn STARGEN 002 for the conversion of rye, wheat, triticale and barley Optimal ph is ph

4 The STARGEN Process Whole ground wheat ph C 56 C ph C Milled Grain Fresh water Thin stillage Proc. Cond. ACTIVATION 30-60minutes Acid Alpha-amylase Viscosity reduction Protease FERMENTATION 4-72 hours STARGEN 002

5 Why processing wheat starch? High value by-products Gluten Fiber Additional benefits for ethanol production: Lower viscosity: No fibers High DS processing Higher ethanol yield in fermentation (>16% v/v) Energy efficiency in Distillation Sustainability Disadvantage of wet-milling High investment High yeast nutrient demand

6 STARGEN 002 Whole Wheat vs Wheat Starch Do we need protease and/or viscosity reducing enzymes? What is the use of the activation step? Which nutrients can/should be used? What are the optimal conditions

7 Need for additional enzymes? 1 STARGEN 002 Fermentation without Protease or Viscosity reducing enzymes Ethanol (% v/v) Wheat starch 25% DS, ph kg/mt dss GC kg/mt dss STARGEN 002 0

8 STARGEN in a wet-mill process STARCH MILK ph C ph C ph ~4 30 C Fresh water Thin stillage Proc. Cond. ACTIVATION 30-60minutes Acid Alpha-amylase FERMENTATION 4-72 hours STARGEN

9 The activation step Temperature C is easily reached by addition of Thin stillage Process condensate Temperature > 53 C reduces lactic acid bacterial growth Addition of Acid Amylase Insurance against temperature excursions Generate some fermentable sugars for yeast start

10 Yeast Nutrients Heavy and Light corn steep water Influence Steep Water on Ethanol yield Influence Steep Water on residual glucose Light steep Heavy steep Ethanol (% v/v) 6 Glucose (% w/v) Light steep Heavy steep Wheat starch 25% DS, ph kg/mt dss GC kg/mt dss STARGEN 002 % heavy or light steep water

11 Commercial yeast nutrients 1 16 Influence Yeast Nutrients on Ethanol yield Commercial yeast nutrients Yeast extract 1 16 Influence Yeast Nutrients on residual glucose Commercial yeast nutrients Yeast extract Ethanol (% v/v) 6 Glucose (% w/v) Wheat starch 25% DS, ph kg/mt dss GC kg/mt dss STARGEN 002

12 Optimizing yeast nutrients 14 Influence extra nutrients on Ethanol yield 1 16 Influence extra nutrients on residual glucose commercial yeast nutrients Plus vitamins Ethanol (% v/v) 6 4 Commercial yeast nutrients Plus vitamins Glucose (% w/v) Wheat starch 25% DS, ph kg/mt dss GC kg/mt dss STARGEN 002

13 Optimal ph 1 Wheat Starch Fermentations with STARGEN 002 at various ph values Ethanol (% v/v) ph 3.5 ph 4.0 ph 5.0 Wheat starch 25% DS, ph kg/mt dss GC kg/mt dss STARGEN 002 0

14 Dose Response 17 Wheat Starch Fermentations with different STARGEN 002 dosages Ethanol (% v/v) kg/mt 1.6 kg/mt 1. kg/mt 2.0 kg/mt >1. kg/mt Starch negative at ± 60 hours Wheat starch 25% DS, ph kg/mt dss GC kg/mt dss STARGEN 002

15 Process recommendations STARCH MILK ph C ph C ph ~4 30 C Fresh water Thin stillage Proc. Cond. ACTIVATION 30-60minutes Acid Alpha-amylase GC626 at 0.29 kg/mt FERMENTATION 4-72 hours STARGEN 002 At 1. kg/mt

16 Comparing Conventional and STARGEN 1 Comparing Conventional and STARGEN on Wheat Starch Ethanol (% v/v) Conventional 500g yeast / MT Conventional 00g yeast / MT STARGEN g yeast / MT Wheat starch 25% DS, ph kg/mt dss GC kg/mt dss STARGEN 002 Or 0.62 kg/mt GC kg/mt GC 536

17 Conclusions STARGEN 002 on Wheat STARCH Reaches High ethanol yields in a simple process Allows high DS fermentations without viscosity issues Little ph adjustment is needed Yeast nutrients need to be controlled No additional yeast needed

18 Acknowledgements Pauline Teunissen Martien Bergsma Gerhard Konieczny-Janda

19 STARGEN Thank You!! Extract maximum value out of your grains!