The sunliquid® process
Ethanol production from lignocellulosic feedstocks
The sunliquid® technology offers an integrated process for the production of cellulosic ethanol from agricultural residues, from pre-treatment to product separation. The efficient conversion is enabled by Clariant’s extensive biotechnology know-how combined with its long-standing experience in process development, chemicals and materials. Highly optimized microorganisms ensure effective conversion of the feedstock into sugars and subsequent fermentation.
Various types of feedstock are converted into cellulosic ethanol after undergoing pre-treatment, enzymatic hydrolysis and fermentation.
The sunliquid® technology is able to handle the following feedstock:
- Cereal straw (wheat, barley …)
- Corn stover
- Bagasse (from sugar cane)
- Rice straw
The sunliquid® process for the production of cellulosic ethanol from agricultural residues
Chemical-free pre-treatment lowers production and investment costs. At the same time, environmental, health and safety risks are minimized.
A small percentage of the pre-treated feedstock is used for enzyme production, which is an integrated part of the process and takes place on-site at the ethanol plant. This makes a major contribution to the economic efficiency of the overall process, resulting in a significant reduction in production costs and ensuring independence from supply shortages and price volatility.
A bespoke enzyme mixture hydrolyses cellulose and hemicellulose chains to form sugar monomers. This step is also termed saccharification. The enzymes are highly optimized based on feedstock and process parameters, resulting in maximum yields and short reaction times under optimal conditions.
Using optimized microorganisms, the sunliquid® process provides for efficient fermentation, giving rise to maximum ethanol yields. This highly-optimized, one-pot system simultaneously converts both C5 and C6 sugars to ethanol, delivering up to 50% more ethanol than conventional processes which convert only C6 sugars.
The innovative and highly energy saving purification method reduces energy demand by up to 50% compared with conventional distillation. It is based on thorough process planning and energy integration, resulting in an entirely energy self-sufficient process.
Characteristics of the sunliquid® technology
- Integrated process with climate-friendly, state-of-the-art technology
- Environmentally friendly process through chemical-free mechanical and thermal pre-treatment
- Flexible use of various raw materials (e.g. cereal straw, corn stover, bagasse)
- Reduction of costs to a minimum through process -integrated enzyme production
- High efficiency through feedstock specific enzymes and efficient one-pot fermentation of C5 and C6 sugary
- Energy self-sufficient production of cellulosic ethanol with up to 95% GHG savings compared to fossil fuels
- Expansion of the regional feedstock base without conflicting uses due to agricultural residues input