Bark Tannin Extraction While Preserving Fuel Value
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for extracting tannic substances from bark in saw milling and pulp mill operations often compromise the fuel value of the bark, making it less suitable for energy production.
Innovation Solution
A method involving disintegration, compression, impregnation with an aqueous solution, dewatering, and recirculation of liquid extracts, followed by the addition of sulphite salt to enhance tannic product quality and maintain or improve the fuel value of the bark.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If extraction of tannic substances from bark is performed using conventional methods, then tannic products are obtained, but the fuel value of the bark is decreased
Solution Approach 1:
The patent extracts only the tannic substances from bark using controlled aqueous extraction at specific pH levels (3-6) and temperatures (40-80°C), leaving the majority of the bark structure intact for fuel use. This selective extraction removes harmful components while preserving energy value.
Solution Approach 2:
The patent employs specific parameter ranges including pH 3-6, temperatures of 40-80°C, and extraction times of 1-24 hours to optimize tannic substance recovery while maintaining bark fuel value. These controlled parameters enable selective extraction without compromising the energy content of the remaining bark.
2Quantity of substance
If extraction methods are applied to recover tannic substances, then tannic products are obtained, but the tanning stability and leather quality are insufficient
Solution Approach 1:
The patent implements a recirculation system where extraction liquid is reused multiple times (2-10 cycles) to progressively extract tannic substances. This feedback mechanism ensures complete recovery of tannic materials while maintaining consistent quality and stability in the final product.
Solution Approach 2:
The patent produces a composite tannic product containing multiple tannic substances extracted under controlled conditions, resulting in a material with enhanced tanning properties and stability. The composite nature of the extract provides superior leather quality compared to single-component extracts.
3Use of energy by moving object
If bark is used for combustion to produce energy, then fuel value is utilized, but tannic products are not recovered
Solution Approach 1:
The patent performs preliminary extraction of tannic substances from bark before combustion. By removing tannic materials first through controlled aqueous extraction, the remaining bark is optimized for fuel use, preventing tannic substance interference during combustion while recovering valuable chemical products.
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
The method produces a tannic product with excellent tanning properties and a bark product with enhanced fuel value, retaining over 93% of the original energy value while reducing chlorine content and increasing dry weight and sulphur content for improved combustion.
Implementation Method 1
adding a sulphite salt to said first liquid extract and to said non-recirculated part of said second liquid extract, or to the optionally combined first and second liquid extracts in a level of 1-25% by weight for providing a first tannic product and a second tannic product
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method for production of at least one tannic product and a bark product having enhanced fuel value is disclosed. According to the invention the method comprises the steps of disintegrating bark; compressing the disintegrated bark to recover a first liquid extract comprising tannic substances; impregnating the compressed bark with a first aqueous impregnation composition at a pH below 7, and at temperature within the range of 45-80°C; dewatering the impregnated bark to recover a second liquid extract comprising tannic substances and a dewatered bark product; recirculating at least a part of the second liquid extract to the impregnation step, wherein the first aqueous impregnation composition comprises a mixture of said recirculated part of the second liquid extract and optionally fresh water; optionally combining said first liquid extract with the non-recirculated part of said second liquid extract; and adding sulphite salt to said first liquid extract and to said non-recirculated part of said second liquid extract, or to the optionally combined first and second liquid extracts in a level of 1-25 % by weight for providing a first tannic product and a second tannic product, or a combined tannic product. Also the tannic product and the bark product obtained from the method is disclosed.