Closed-loop system for growth of aquatic biomass and gasification thereof

Abstract

Processes, systems, and methods for producing combustible gas from wet biomass are provided. In one aspect, for example, a process for generating a combustible gas from a wet biomass in a closed system is provided. Such a process may include growing a wet biomass in a growth chamber, moving at least a portion of the wet biomass to a reactor, heating the portion of the wet biomass under high pressure in the reactor to gasify the wet biomass into a total gas component, separating the gasified component into a liquid component, a non-combustible gas component, and a combustible gas component, and introducing the liquid component and non-combustible gas component containing carbon dioxide into the growth chamber to stimulate new wet biomass growth.

1 . A process for generating a combustible gas from a wet biomass in a closed system, comprising:
 growing a wet biomass including an aquatic species selected from the group consisting essentially of: algae, cyanobacteria, diatoms, aquatic plants, and mixtures thereof in a growth chamber;   moving at least a portion of the wet biomass to a reactor;   heating the portion of the wet biomass under pressure with a catalyst in the reactor to gasify the wet biomass into a gasified component;   separating the gasified component into a condensed liquid, a non-combustible gas component, and a combustible gas component; and   introducing the non-combustible gas component containing carbon dioxide and the liquid component into the growth chamber to stimulate wet biomass growth.   
   
   
       2 . The process of  claim 1 , wherein the combustible gas component includes methane. 
   
   
       3 . The process of  claim 1 , wherein the combustible gas component includes hydrogen. 
   
   
       4 . The process of  claim 1 , wherein the gasified component is removed from the reactor prior to isolating the combustible gas component. 
   
   
       5 . The process of  claim 1 , further comprising introducing a nutrient recaptured from the harvested biomass into the growth chamber to stimulate new biomass growth. 
   
   
       6 . The process of  claim 5 , wherein the nutrient is recaptured from the gasified component. 
   
   
       7 . The process of  claim 5 , wherein the nutrient is recaptured during a preprocessing step which occurs prior to gasification of the harvested biomass. 
   
   
       8 . The process of  claim 5 , wherein the nutrient is ammonia. 
   
   
       9 . The process of  claim 5 , wherein the nutrient is an element including a member selected from the group consisting of nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulfur (S), phosphorus (P), iron (Fe), and combinations thereof. 
   
   
       10 . The process of  claim 5 , wherein the nutrient is introduced into the growth chamber as a liquid. 
   
   
       11 . The process of  claim 1 , wherein the non-combustible gas component is carbon dioxide. 
   
   
       12 . The process of  claim 11 , wherein introducing the non-combustible gas component containing carbon dioxide into the growth chamber further includes:
 dissolving the carbon dioxide in water; and   introducing the water containing the dissolved carbon dioxide into the growth chamber.   
   
   
       13 . The process of  claim 1 , wherein the aquatic species is an algae. 
   
   
       14 . The process of  claim 13 , wherein the algae includes a species from the order Cladophorales or Ulvales, and combinations thereof. 
   
   
       15 . The process of  claim 1 , wherein the aquatic species is a cyanobacteria. 
   
   
       16 . The process of  claim 15 , wherein the cyanobacteria includes a species from the order Oscillatoriales or Nostocales, and combinations thereof. 
   
   
       17 . The process of  claim 1 , wherein the aquatic species is an aquatic plant. 
   
   
       18 . The process of  claim 17  wherein the aquatic plant includes species from the genus  Eichhornia  or  Pistia.    
   
   
       19 . The process of  claim 1 , wherein the aquatic species is a diatom. 
   
   
       20 . The process of  claim 19 , wherein the diatom includes species from the genus  Navicula, Fragilaria, Nitzschia , or  Chaetoceros.