NOVELTY - Device (1) for production of methane and chemicals from sequestered carbon, comprises: an apparatus providing a source of carbon; a first processing chamber (102) configured and arranged to receive water (130), the carbon and a biomass, and arranged to subject the biomass to a pressure greater than atmospheric pressure; and a second processing chamber (104) in fluid flow communication with the first processing chamber, and configured and arranged for substantial anaerobic digestion of at least a portion of the biomass while in the second chamber, so that methane is a digestion product.    USE - The device is useful for production of methane and chemicals from sequestered carbon including fermentation substrate, biopolymer, bioplastic, oil, a pigment, biochar, fiber, protein, vitamin, fertilizer, animal feed, metal (claimed) (e.g. mercury, chromium or arsenic) or fibers.    ADVANTAGE - The device (deep well reactor): provides maximized elimination of carbon dioxide (major greenhouse gas and an air pollutant) from carbon dioxide laden air stream including atmospheric air, combustion gases of power plants or land fill gases, and transforms the carbon dioxide into a photosynthetic biomass; utilizes LED lights which provides consistent and controlled frequencies of visible and infra red light, thus maximum photosynthetic and growth rates can be achieved in return for the energy utilized to provide light; eliminates chemical carbon from effluents using a heterotrophic biomass, and transforms it into methane; allows substantially reduced land requirements; and allows easy separation of algae biomass from the liquid.    DETAILED DESCRIPTION - Device (1) for production of methane and chemicals from sequestered carbon, comprises: an apparatus providing a source of carbon; a first processing chamber configured and arranged to receive water (130), the carbon and a biomass, where the biomass metabolizes at least a portion of the carbon so as to produce additional biomass; and a first processing chamber is configured and arranged to subject the biomass to a pressure greater than atmospheric pressure; and a second processing chamber in fluid flow communication with the first processing chamber, and configured and arranged for substantial anaerobic digestion of at least a portion of the biomass while in the second chamber, so that methane is a digestion product. INDEPENDENT CLAIMS are also included for:    (1) a deep well bioreactor for production of methane from carbon dioxide, comprising: (a) an anaerobic digester consisting an elongated outer shaft having upper and lower ends, an elongated middle shaft generally coaxially located within the outer shaft and having upper and lower ends, where the lower end of the middle shaft is in fluid flow communication with the lower end of the outer shaft, a methane collection apparatus in flow communication with upper end of the outer shaft, many methanogenic microorganisms located within the middle and outer shafts, for substantial anaerobic digestion of a carbon-sequestering biomass, thus methane is a digestion product; (b) a biomass incubator generally coaxially located within the middle shaft of the anaerobic digester, and comprises an elongated cylindrical inner shaft having an interior and upper and lower ends, where the upper end of the biomass incubator is in fluid flow communication with the upper end of the middle shaft of the anaerobic digester; (c) a carbon inlet apparatus in communication with the interior of the elongated cylindrical inner shaft, and configured and arranged to provide at least some carbon distribution to water located in the interior of the inner shaft; and (d) a carbon-sequestering biomass located in the interior of the inner shaft, where the carbon-sequestering biomass metabolizes at least a portion of the provided carbon so as to produce additional carbon-sequestering biomass, and then the carbon-sequestering biomass is at least partially converted to methane in the anaerobic digester;    (2) method (I) for producing methane from carbon dioxide, comprising: (a1) exposing a photosynthetic biomass to carbon dioxide, light and nutrients; (a2) allowing the photosynthetic biomass to metabolize at least some of the carbon dioxide, thus additional photosynthetic biomass is produced; (a3) mixing a portion of the photosynthetic biomass with a methanogenic biomass; (a4) allowing the methanogenic biomass to anaerobically digest the portion of the photosynthetic biomass, thus to methane is produced as a digestion product;    (3) method (II) for production of methane from carbon dioxide in a deep well bioreactor, comprising: (b1) providing many methanogenic microorganisms located in an anaerobic digester; (b2) providing a carbon-sequestering biomass located in an incubator located coaxially within the anaerobic digester, where the incubator is in fluid flow communication with the anaerobic digester; (b3) mixing a carbon source with the carbon-sequestering biomass; (b4) allowing the carbon-sequestering biomass to metabolize at least a portion of the carbon of the carbon source, thus additional carbon-sequestering biomass is produced; (b5) mixing a portion of the carbon-sequestering biomass with the many methanogenic microorganisms; and (b6) allowing the methanogenic microorganisms to substantially anaerobically digest at least a portion of the carbon-sequestering biomass; and    (4) method (III) for producing a product from a carbon sequestering biomass in a deep well bioreactor, comprising: (c1) providing a source of carbon; (c2) incubating the source of carbon with a biomass, where the biomass metabolizes at least a portion of the carbon of the carbon source so as to produce additional biomass; and (c3) subjecting at least a portion of the biomass to physical-chemical treatment, so as to produce a product comprising fermentation substrate, a biopolymer, a bioplastic, an oil, a pigment, a biochar, a metal, a fiber, a protein, a vitamin, a fertilizer and an animal feed.    DESCRIPTION OF DRAWING(S) - The figure shows a partially schematic view of a deep well bioreactor for carbon sequestration and methane production.    Device (1)    First processing chamber (102)    Second processing chamber (104)    Light source (124)    Water (130)