Method for high energy density biomass-water slurry

Abstract

An energy efficient process for converting biomass into a higher carbon content, high energy density slurry. Water and biomass are mixed at a temperature and under a pressure that are much lower than in prior processes, but under a non-oxidative gas, which enables a stable slurry to be obtained containing up to 60% solids by weight, 20-40% carbon by weight, in the slurry. The temperature is nominally about 200° C. under non-oxidative gas pressure of about 150 psi, conditions that are substantially less stringent than those required by the prior art.

1 . A process for converting biomass into a higher carbon content, high energy density slurry, comprising providing a mixture of biomass and water containing up to 60% solids, and heating the mixture under a non-oxidative gas whereby to obtain a stable slurry to be obtained containing 20-40% carbon by weight in the slurry. 
     
     
         2 . The process of  claim 1  in which the mixture is heated to a temperature in the range of 170 to 250° C. 
     
     
         3 . The process of  claim 1  in which the mixture is heated under a non-oxidative gas at a pressure of 100 to 400 psi. 
     
     
         4 . The process of  claim 1  in which the mixture is heated to a temperature of about 200° C. under a non-oxidative gas pressure of about 150 psi. 
     
     
         5 . The process of  claim 1  in which the non-oxidative gas is selected from the group consisting of argon, helium, nitrogen, hydrogen, carbon dioxide, or gaseous hydrocarbons, or mixtures thereof. 
     
     
         6 . A process for converting biomass into a higher carbon content, high energy density slurry, comprising providing a mixture of biomass and water containing 50% solids, and heating the mixture to a temperature of about 200° C. under a non-oxidative gas pressure of about 150 psi whereby to obtain a stable slurry. 
     
     
         7 . In a process for in which a biomass slurry is fed into a hydro-gasification reactor, the step of converting the biomass into a higher carbon content, high energy density slurry, comprising providing a mixture of biomass and water containing up to 60% solids, and heating the mixture under a non-oxidative gas whereby to obtain a stable slurry. 
     
     
         8 . The process of  claim 7  in which the mixture is heated to a temperature in the range of 170 to 250° C. 
     
     
         9 . The process of  claim 7  in which the mixture is heated under a non-oxidative gas at a pressure of 100 to 400 psi. 
     
     
         10 . The process of  claim 7  in which the mixture is heated to a temperature of about 200° C. under a non-oxidative gas pressure of about 150 psi. 
     
     
         11 . The process of  claim 7  in which the non-oxidative gas is selected from the group consisting of argon, helium, nitrogen, hydrogen, carbon dioxide, or gaseous hydrocarbons, or mixtures thereof. 
     
     
         12 . In a process in which a biomass slurry is fed into a hydro-gasification reactor, the step of converting the biomass into a higher carbon content, high energy density slurry, comprising providing a mixture of biomass and water containing 50% solids, and heating the mixture to a temperature of about 200° C. under a non-oxidative gas pressure of about 150 psi whereby to obtain a stable slurry. 
     
     
         13 . The process of  claim 12  in which the non-oxidative gas is selected from the group consisting of argon, helium, nitrogen, hydrogen, carbon dioxide, or gaseous hydrocarbons, or mixtures thereof.