Continuous Starch Liquefaction Using Enzyme-Expressing Plant Material
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ethanol production from plant starch involves a complex and costly process that includes multiple steps, such as liquefaction and saccharification, which require significant heating, cooling, and pH adjustments, leading to inefficiencies and increased costs.
Innovation Solution
The process involves using transgenic plant material expressing starch-digesting enzymes to perform liquefaction directly in a pipe or tube system without a slurry tank, reducing the need for jet cooking and secondary liquefaction steps, and eliminating pH adjustments, thereby simplifying the process and reducing energy consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional enzymatic liquefaction process is used with slurry tank and jet cooker, then starch hydrolysis is completed, but processing time and energy consumption increase significantly
Solution Approach 1:
The patent combines multiple separate process steps (liquefaction, saccharification, pH adjustment) into a single integrated continuous process occurring within a pipe system. The enzyme-expressing plant material is mixed with starch slurry and processed through heating and cooling zones in sequence, eliminating the need for separate tanks and transfer operations, thereby reducing processing time while maintaining ethanol production efficiency
Solution Approach 2:
The patent incorporates starch-digesting enzymes into the plant material beforehand through genetic modification. This preliminary action allows the enzymes to be immediately available when the plant material is mixed with starch slurry, eliminating the need for separate enzyme addition steps and reducing overall processing time in the liquefaction process
2Productivity
If conventional enzymatic liquefaction process is used with jet cooking, then starch gelatinization is completed, but energy consumption increases
Solution Approach 1:
The patent implements a continuous processing system where the starch slurry with enzyme-expressing plant material flows continuously through heating and cooling zones. This continuous action maintains optimal conditions for enzyme activity throughout the process, achieving complete starch hydrolysis without the need for repeated heating cycles or holding steps, thereby reducing energy consumption while maintaining hydrolysis efficiency
Solution Approach 2:
The patent utilizes controlled temperature changes along the pipe length to optimize different process stages. The slurry is heated to gelatinize starch, then cooled to activate enzyme activity, with temperature parameters dynamically adjusted along the flow path. This parameter optimization allows efficient starch hydrolysis without excessive energy input required by conventional constant high-temperature jet cooking
3Reliability
If pH adjustment is performed in conventional process, then enzyme activity is optimized, but process complexity and cost increase
Solution Approach 1:
The patent employs plant material genetically modified to express starch-digesting enzymes that function across a broad pH range. The enzyme system is self-regulating and does not require external pH adjustment to maintain activity, eliminating the need for pH monitoring and adjustment equipment while ensuring reliable enzyme performance throughout the continuous processing operation
4Productivity
If slurry is cooled to ambient temperature, then fermentation can proceed, but slurry viscosity increases and places pressure on heat exchanger
Solution Approach 1:
The patent maintains the slurry in a dynamic continuous flow state through the cooling section rather than allowing it to stagnate. The constant movement prevents excessive thickening even at ambient temperature, and the gradual cooling gradient along the pipe allows viscosity to increase progressively rather than abruptly, reducing stress on the heat exchanger while preparing the slurry for fermentation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances ethanol production efficiency by reducing processing time, energy usage, and costs, while maintaining or improving the quality of the ethanol and co-products like DDG(S), and allows for higher solids loading and lower viscosity, facilitating smoother flow through equipment.
Implementation Method 1
transgenic plant material expressing a starch-digesting enzyme
Implementation Method 2
starch is hydrolyzed into fermentable sugars
Implementation Method 3
aqueous starch slurry is heated so that the granular starch in the slurry swells and bursts, dispersing starch molecules into the solution
Implementation Method 4
The slurry is heated to between 80-85 degrees C. to initiate gelatinization
Implementation Method 5
the slurry must be cooled to about ambient temperature
Data Source
AI summary
The presently disclosed subject matter provides improved processes for processing starch from plant sources, including processes for starch liquefaction, for simultaneous liquefaction and saccharification, and for the preparation of ethanol. These processes can be performed without a pH adjustment and at relatively low temperatures. The processes can involve the use of starch-containing plant material derived from plants that express starch-digesting enzymes. The presently disclosed subject matter further relates to improved processes for the preparation of other starch-derived products, including dried distiller grain (dried distiller grain) and dried distiller grain and solubles (dried distiller grain and solubles), and to the starch-derived products, themselves.