METHOD FOR PRODUCTION OF TANNIC SUBSTANCES AND A BARK PRODUCT WITH ENHANCED FUEL VALUE

• Main Authors: MESIC, Narcis, SOLHAGE, Fredrik
• Format: Patent
• Language: English
• Published: 13.08.2020
• Subjects: ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE ORUNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; DERIVATIVES OF NATURAL MACROMOLECULAR COMPOUNDS; FIRELIGHTERS; FUELS; FUELS NOT OTHERWISE PROVIDED FOR; LIQUEFIED PETROLEUM GAS; LUBRICANTS; METALLURGY; NATURAL GAS; ORGANIC MACROMOLECULAR COMPOUNDS; PEAT; PETROLEUM, GAS OR COKE INDUSTRIES; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BYSUBCLASSES C10G, C10K; TECHNICAL GASES CONTAINING CARBON MONOXIDE; THEIR PREPARATION OR CHEMICAL WORKING-UP

A method for production of at least one tannic product and a bark product having enhanced fuel value is disclosed. The method comprises 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.