Cellulosic and lignocellulosic structural materials and methods and systems for manufacturing such materials

Abstract

Methods of treating wood and wood products include irradiating untreated wood having a first molecular weight with ionizing radiation to cause an increase in the molecular weight of a cellulosic component of the wood to a second, relatively higher molecular weight.

What is claimed is: 
     
         1 . A method of processing wood to produce a finished product, the method comprising:
 debarking logs to produce debarked logs;   sawing the debarked logs to produce sawn lumber;   edging the sawn lumber to produce edged lumber;   trimming the edged lumber to produce trimmed lumber;   manufacturing the finished product from the trimmed lumber; and   during the method, irradiating one or more of the debarked logs, the sawn lumber, the edged lumber, the trimmed lumber and the finished product.   
     
     
         2 . The method of  claim 1 , wherein irradiating is by ionizing radiation. 
     
     
         3 . The method of  claim 1 , wherein irradiating is by ultraviolet rays. 
     
     
         4 . The method of  claim 2 , wherein the ionizing radiation is X-rays. 
     
     
         5 . The method of  claim 2 , wherein the ionizing radiation is electron beam radiation. 
     
     
         6 . The method of  claim 2 , wherein the ionizing radiation is by particles heavier than electrons. 
     
     
         7 . The method of  claim 5 , wherein the particles are positively charged. 
     
     
         8 . The method of  claim 5 , wherein the particles are negatively charged. 
     
     
         9 . The method of  claim 1 , further comprising quenching radicals in one or more of:
 debarked logs that have been irradiated, sawn lumber that has been irradiated, edged lumber that has been irradiated, and the finished product that has been irradiated.   
     
     
         10 . The method of  claim 9 , wherein quenching radicals is by contact with a gas comprising nitrogen, oxygen, acetylene, ethylene, a chlorinated ethylene, a chlorofluoroethylene, or propylene. 
     
     
         11 . The method of  claim 1 , wherein irradiating is from multiple directions. 
     
     
         12 . The method of  claim 1  further comprising drying the sawn lumber to a moisture content of 6 to 18 weight percent water. 
     
     
         13 . The method of  claim 1  further comprising drying the sawn lumber to a moisture content of less than 5 weight percent water. 
     
     
         14 . The method of  claim 1  wherein two or more sources of radiation are used for irradiation.