Dewatering Green Sapwood Using Carbon Dioxide

PDF Publication Title:

Dewatering Green Sapwood Using Carbon Dioxide ( dewatering-green-sapwood-using-carbon-dioxide )

Next Page View | Return to Search List

Text from PDF Page: 001

molecules Article Dewatering Green Sapwood Using Carbon Dioxide Undergoing Cyclical Phase Change between Supercritical Fluid and Gas Robert A. Franich 1,*, Roger Meder 2 and Volker C. Behr 3 1 2 3 * Correspondence: chemipreneur@gmail.com; Tel.: +64-21-261-0743 Academic Editor: Mauro Banchero Received: 29 October 2020; Accepted: 15 November 2020; Published: 17 November 2020 Chemipreneur Limited, Rotorua 3010, New Zealand Meder Consulting, Queensland QLD 4017, Australia; roger@mederconsulting.com Experimental Physics 5, University of Würzburg, 97074 Würzburg, Germany; behr@physik.uni-wuerzburg.de Abstract: Conventional kiln drying of wood operates by the evaporation of water at elevated temperature. In the initial stage of drying, mobile water in the wood cell lumen evaporates. More slowly, water bound in the wood cell walls evaporates, requiring the breaking of hydrogen bonds between water molecules and cellulose and hemicellulose polymers in the cell wall. An alternative for wood kiln drying is a patented process for green wood dewatering through the molecular interaction of supercritical carbon dioxide with water of wood cell sap. When the system pressure is reduced to below the critical point, phase change from supercritical fluid to gas occurs with a consequent large change in CO2 volume. This results in the efficient, rapid, mechanical expulsion of liquid sap from wood. The end-point of this cyclical phase-change process is wood dewatered to the cell wall fibre saturation point. This paper describes dewatering over a range of green wood specimen sizes, from laboratory physical chemistry studies to pilot-plant trials. Magnetic resonance imaging and nuclear magnetic resonance spectroscopy were applied to study the fundamental mechanisms of the process, which were contrasted with similar studies of conventional thermal wood drying. In conclusion, opportunities and impediments towards the commercialisation of the green wood dewatering process are discussed. Keywords: supercritical CO2; phase-change; sapwood; dewatering; physical chemistry; nuclear magnetic resonance spectroscopy; magnetic resonance imaging 1. Introduction 1.1. Conventional Processes for Drying Green Industrial Wood Wood freshly sawn from a log, often referred to as “green” wood, usually has a high sapwood moisture content, particularly in softwood species such as pines. A well-known example of an industrial wood grown in high-production plantation forests in New Zealand is radiata pine (Pinus radiata D. Don), the green sapwood moisture content of which is typically ca. 150–200% based on the wood material oven-dry weight [1]. The conversion of green wood to utility wood requires removing the water to a point where the wood material has dimensional and conformational stability and is non-perishable. The moisture content of dry wood (

PDF Image | Dewatering Green Sapwood Using Carbon Dioxide


PDF Search Title:

Dewatering Green Sapwood Using Carbon Dioxide

Original File Name Searched:


DIY PDF Search: Google It | Yahoo | Bing

SeaMerlin The SeaMerlin Engine is a water based gas leverage turbine for marine propulsion, seawater distillation, oceanwater CO2 harvesting, and more.

About: More about Infinity Turbine and the quest for the Xprize... More Info

Strategy and Consulting Services: Renewable energy strategy, Organic Rankine Cycle, CO2 energy, and Sonification technology consulting... More Info

@elonmusk XPrize $100 million CO2 Challenge: Carbon Removal Prize Challenge Sponsored by Elon Musk... More Info

CO2 Phase Change Demonstrator: Experiment with gas to liquids (CO2 to alcohol) using Nafion and our phase change demonstrator cart (we can ship worldwide)... More Info

CO2 GTL Gas to Liquids Experimental Platform: Experiment with gas to liquids (CO2 to alcohol) using Nafion (electrolyzer membrane) and our phase change demonstrator cart (we can ship worldwide). CO2 goes supercritical at 31 C. This is a experimental platform which you can use to demonstrate phase change with low heat. Includes integration area for small CO2 turbine, static generator, Nafion pellets, Nafion membrate, or Nafion tubes... More Info

Concept: The concept of the SeaMerlin Engine is to convert or supplement existing marine vessel propulsion to a gas leverage turbine which scavenges CO2 from saltwater at the same time it provides vessel thrust.

CONTACT TEL: 608-238-6001 Email: greg@seamerlin.com | RSS | AMP