Continuous-Batch Hybrid Process for Production of Oil and Other Useful Products From Photosynthetic Microbes

Abstract

A process for cultivating photosynthetic microbes comprising closed Systems for continuous cultivation and Open Systems for batch cultivation, in which (a) the Closed System Area occupies no more than 20% of the Total Land Area of the cultivation facility; (b) batch cultures in the Open Systems are initiated with an inoculum from the Closed Systems containing a cell biomass of no less than 5% of the carrying capacity of said Open System; (c) the doubling rate of said photosynthetic microbe is no less than once every 16 hours; and (d) the residence time of the batch culture in said Open System is no more than a period of 5 days.

1 - 13 . (canceled) 
     
     
         14 . A process for synthesizing oil, comprising:
 selecting photosynthetic microbes that double in biomass in approximately 16 hours or less when supplied with sufficient carbon dioxide in an open pond having a carrying capacity;   injecting stack gases having carbon dioxide concentrations of at least 3.5% into a photobioreactor having a maximum culture depth of at most approximately 30 to 40 centimeters, wherein said stack gases are selected from the source consisting of burning a fossil fuel, industrial production of chemicals, refining of oil and gas, and geological extraction of fossil fuels;   introducing said microbes into said photobioreactor;   providing said microbes with sufficient nutrients in said photobioreactor to avoid nutrients being a limiting factor to growth;   turbulent mixing of said microbes throughout said photobioreactor, whereby said microbes undergo continuous exponential growth in said photobioreactor;   inoculating an initial biomass of said microbes that is no less than 5% of said carrying capacity of said open pond from said closed photobioreactor into said open pond;   supplying carbon dioxide to said open system to maintain approximately constant pH and to supply sufficient carbon dioxide to said microbes and to replace carbon dioxide removed by said microbes; and   maintaining said microbes in said open pond with high nutrient concentrations for at most 5 days, whereby initial conditions of high light intensity and high nutrient concentrations favor continued exponential growth for a short period, but wherein growth becomes limited by nitrogen availability which inhibits protein synthesis, whereby oil content is increased.   
     
     
         15 . A process for biosynthesis of oil, comprising:
 selecting photosynthetic microbes that double in biomass in approximately 16 hours or less when supplied with sufficient carbon dioxide in an open pond having a carrying capacity;   dissolving stack gases having carbon dioxide concentrations of at least 3.5% in a culture medium in a photobioreactor having a maximum culture depth of at most approximately 30 to 40 centimeters, wherein said stack gases are selected from a source selected from the group consisting of burning a fossil fuel, industrial production of chemicals, refining of fossil fuels, and geological extraction of fossil fuels;   introducing said microbes into said medium in said photobioreactor;   providing said microbes with sufficient nutrients in said medium to avoid nutrients being a limiting factor to growth;   turbulent mixing of said microbes in said medium throughout said photobioreactor to provide a substantially homogeneous distribution of said microbes in said medium, whereby said microbes undergo continuous exponential growth in said photobioreactor;   inoculating an initial biomass of said microbes that is no less than 5% of said carrying capacity of said open pond from said closed photobioreactor into said open pond;   supplying stack gases having carbon dioxide concentrations of at least 3.5% to said open pond to maintain approximately constant pH and to supply sufficient carbon dioxide to said microbes and to replace carbon dioxide removed by said microbes, wherein said stack gases are selected from a source selected from the group consisting of burning a fossil fuel, industrial production of chemicals, refining of fossil fuels, and geological extraction of fossil fuels; and   maintaining said microbes in said open pond with high nutrient concentrations for at most 5 days, whereby initial conditions of high light intensity and high nutrient concentrations favor continued exponential growth for a short period, but wherein growth becomes limited by nitrogen availability which inhibits protein synthesis, whereby oil content is increased.   
     
     
         16 . A process for synthesizing biomass on a land area, comprising:
 selecting photosynthetic microbes that double in biomass in approximately 4 hours or less when supplied with sufficient carbon dioxide in an open pond having a carrying capacity;   introducing said microbes into a photobioreactor having a maximum culture depth of at most approximately 30 to 40 centimeters, wherein said photobioreactor occupies less than 20% of said land area;   providing said microbes with sufficient nutrients in said photobioreactor to avoid nutrients being a limiting factor to growth;   turbulent mixing of said microbes throughout said photobioreactor, whereby said microbes undergo continuous exponential growth in said photobioreactor;   inoculating an initial biomass of said microbes that is no less than 15% of said carrying capacity from said photobioreactor into said open pond, wherein said open pond occupies more than 80% of said land area;   supplying carbon dioxide to said open pond to maintain approximately constant pH and to supply sufficient carbon dioxide to said microbes an to replace carbon dioxide removed by said microbes; and   maintaining said microbes in said open pond with high nutrient concentrations for at most 1 day, whereby initial conditions of high light intensity and high nutrient concentrations favor continued exponential growth for a short period, but wherein growth becomes limited by light due to proliferation of cells.   
     
     
         17 . A process for biosynthesis of oil, comprising:
 selecting photosynthetic microbes that double in biomass in approximately 16 hours or less when supplied with sufficient carbon dioxide in an open pond having a carrying capacity;   dissolving stack gases having carbon dioxide concentrations of at least 3.5% in a culture medium in a photobioreactor having a maximum culture depth of at most approximately 30 to 40 centimeters, wherein said stack gases are selected from a source selected from the group consisting of burning a fossil fuel, industrial production of chemicals, refining of fossil fuels, and geological extraction of fossil fuels;   introducing said microbes into said medium in said photobioreactor;   providing said microbes with sufficient nutrients in said medium to avoid nutrients being a limiting factor to growth;   turbulent mixing of said microbes in said medium throughout said photobioreactor, whereby said microbes undergo continuous exponential growth in said photobioreactor;   inoculating an initial biomass of said microbes that is no less than 5% of said carrying capacity of said open pond from said closed photobioreactor into said open pond;   supplying carbon dioxide to said open pond to maintain approximately constant pH and to supply sufficient carbon dioxide to said microbes and to replace carbon dioxide removed by said microbes; and   maintaining said microbes in said open pond with high nutrient concentrations for at most 5 days, whereby initial conditions of high light intensity and high nutrient concentrations favor continued exponential growth for a short period, but wherein growth becomes limited by nitrogen availability which inhibits protein synthesis, whereby oil content is increased.   
     
     
         18 . A process for synthesizing biomass feedstock, comprising:
 selecting photosynthetic microbes that double in biomass in approximately 4 hours or less when supplied with sufficient carbon dioxide in an open pond having a carrying capacity;   dissolving stack gases having carbon dioxide concentrations of at least 3.5% in a culture medium in a photobioreactor having a maximum culture depth of at most approximately 30 to 40 centimeters, wherein said stack gases are selected from a source selected from the group consisting of burning a fossil fuel, industrial production of chemicals, refining of fossil fuels, and geological extraction of fossil fuels;   introducing said microbes into said medium in said photobioreactor;   providing said microbes with sufficient nutrients in said medium to avoid nutrients being a limiting factor to growth;   turbulent mixing of said microbes in said medium throughout said photobioreactor, whereby said microbes undergo continuous exponential growth in said photobioreactor;   inoculating an initial biomass of said microbes that is no less than 15% of said carrying capacity of said open pond from said closed photobioreactor into said open pond;   supplying carbon dioxide to said open pond to maintain approximately constant pH and to supply sufficient carbon dioxide to said microbes an to replace carbon dioxide removed by said microbes; and   maintaining said microbes in said open pond with high nutrient concentrations for at most 1 day, whereby initial conditions of high light intensity and high nutrient concentrations favor continued exponential growth for a short period, but wherein growth becomes limited by light due to proliferation of cells.   
     
     
         19 . A device for cultivating photosynthetic microbes on a land area, comprising:
 one or more culture vessels transparent to visible light, each culture vessel providing a culture depth of at most approximately 30 to 40 centimeters, wherein said culture vessels cover a plan area of said land area and portions of said land area between said culture vessels define an inert area;   a nutrient medium in each of said culture vessels;   turbulent flow means for creating turbulent flow throughout said nutrient medium in each of said culture vessels, wherein said turbulent flow is sufficiently low to prevent mechanical shear from damaging cells, said culture vessels, said nutrient medium and said turbulent flow means defining one or more photobioreactors;   wherein said plan area and said inert area occupy no more than 20% of said land area; and   one or more open ponds, each having a carrying capacity, which together occupy no less than 80% of said land area;   whereby a biomass of microbes comprising at least 5% of said carrying capacity for each of said open ponds can be inoculated from said photobioreactors into said open ponds.   
     
     
         20 . (canceled) 
     
     
         21 . A process for synthesizing biomass on a land area, comprising:
 selecting photosynthetic microbes that double in biomass in 16 hours or less when supplied with sufficient carbon dioxide in an open pond having a carrying capacity;   introducing said microbes into a photobioreactor having a maximum culture depth of at most approximately 30 to 40 centimeters, wherein said photobioreactor occupies less than 20% of said land area;   providing said microbes with sufficient nutrients in said photobioreactor to avoid nutrients being a limiting factor to growth;   turbulent mixing of said microbes throughout said photobioreactor, whereby said microbes undergo continuous exponential growth in said photobioreactor;   inoculating an initial biomass of said microbes that is no less than 5% of said carrying capacity from said photobioreactor into said open pond, wherein said open pond occupies more than 80% of said land area;   supplying carbon dioxide to said open pond to maintain approximately constant pH and to replace carbon dioxide removed by said microbes; and   maintaining said microbes in said open pond with high nutrient concentrations for at most 5 days, whereby initial conditions of high light intensity and high nutrient concentrations favor continued exponential growth for a short period, but wherein growth becomes limited by light due to proliferation of cells.   
     
     
         22 . A process according to  claim 14 , wherein said injecting step is performed using a photobioreactor having a maximum culture depth of at most approximately 15 to 20 centimeters. 
     
     
         23 . A process according to  claim 15 , wherein said dissolving step is performed using a photobioreactor having a maximum culture depth of at most approximately 15 to 20 centimeters. 
     
     
         24 . A process according to  claim 16 , wherein said introducing step is performed using a photobioreactor having a maximum culture depth of at most approximately 15 to 20 centimeters. 
     
     
         25 . A process according to  claim 17 , wherein said dissolving step is performed using a photobioreactor having a maximum culture depth of at most approximately 15 to 20 centimeters. 
     
     
         26 . A process according to  claim 18 , wherein said dissolving step is performed using a photobioreactor having a maximum culture depth of at most approximately 15 to 20 centimeters. 
     
     
         27 . A process according to  claim 19 , wherein at least one of said culture vessels has a culture depth of at most approximately 15 to 20 centimeters. 
     
     
         28 . A process according to  claim 21 , wherein said introducing step is performed using a photobioreactor having a maximum culture depth of at most approximately 15 to 20 centimeters.