A method of converting CO.sub.2 gas produced during industrial processes comprising contacting methanogenic archaea with the CO.sub.2 gas under suitable conditions to produce methane.

Methods of capturing carbon by microbial fermentation of a gaseous substrate comprising CO. The methods include converting CO to one or more products including alcohols and/or acids and optionally capturing CO2 to improve overall carbon capture. In certain aspects, also disclosed are to processes for producing alcohols, particularly ethanol, from industrial waste streams, particularly steel mill off-gas.

The present invention can reduce the amount of carbon dioxide exhausted during the production of an organic substance from waste. The apparatus 1 for producing an organic substance, comprises a synthesis gas generation furnace 11 and a fermenter 13. The synthesis gas generation furnace 11 generates a synthesis gas by partial oxidation of waste. The fermenter 13 contains microorganisms which produce an organic substance from the synthesis gas. The fermenter 13 comprises a first fermenter unit 13a and a second fermenter unit 13b.

Apparatus, systems and methods are provided for the improved use of waste heat recovery systems which utilize the organic Rankine cycle (ORC) to generate mechanical and/or electric power from heat sources generating power from biofuel such as biogas produced during the anaerobic digestion process. Waste heat energy obtained from heat source(s) is provided to one or more ORC system(s) which may be operatively coupled to electric generator(s). A heat coupling subsystem provides the requisite condensation of ORC working fluid by transferring heat from ORC working fluid to another process or system, such as anaerobic digester tank(s), to provide heat energy that enhances the production of fuel for the prime mover(s) without requiring the consumption of additional energy for that purpose.

The present invention provides an apparatus and a method which can be used for producing an organic substance effectively from a synthesis gas obtained from a waste incinerator. The apparatus 1 for producing an organic substance from waste, comprises a synthesis gas generation furnace 11, a fermenter 13, and a nutrient feeder. The synthesis gas generation furnace 11 generates a synthesis gas by partial oxidation of waste. The fermenter 13 contains a microorganism which produces an organic substance from the synthesis gas. The nutrient feeder 12 feeds a solid or liquid nutrient to the fermenter 13 when an amount of the synthesis gas supplied to the fermenter 13 is insufficient.

Compositions and methods for a hybrid biological and chemical process that captures and converts carbon dioxide and/or other forms of inorganic carbon and/or CI carbon sources including but not limited to carbon monoxide, methane, methanol, formate, or formic acid, and/or mixtures containing CI chemicals including but not limited to various syngas compositions, into organic chemicals including biofuels or other valuable biomass, chemical, industrial, or pharmaceutical products are provided. The present invention, in certain embodiments, fixes inorganic carbon or CI carbon sources into longer carbon chain organic chemicals by utilizing microorganisms capable of performing the oxyhydrogen reaction and the autotrophic fixation of CO.sub.2 in one or more steps of the process.

The present invention concerns a method of cultivation of microorganisms in a bioreactor wherein the culture medium comprises carbon dioxide (CO.sub.2) as carbon source. The CO.sub.2 supply in the bioreactor is regulated using a membrane contactor.

A photobioreactor has an optical waveguide formed at least in part from a highly scattering optically transmitting polymer. The optical waveguide has a light distributing part immersed in a container holding photoactive biological material and a light collecting part outside the container.

A system comprising a collocated thermal plant, water source, CO.sub.2 source and biomass growth module is disclosed. A method of improving the environment by utilizing the system is disclosed.

The disclosure is directed to a process and an apparatus for providing a feedstock. A gaseous feed stream comprising at least one hydrocarbon is passed to a reforming unit followed by a water gas shift reaction zone to provide a first gaseous stream comprising H.sub.2, CO, and CO.sub.2. The first gaseous stream is fed a hydrogen separation zone to separate it into a hydrogen enriched stream and a second gaseous stream comprising CO, CO.sub.2 and H.sub.2. The second gaseous stream is fed to a CO.sub.2 to CO conversion system to produce a third gaseous stream comprising H.sub.2 and CO having a H.sub.2:CO molar ratio of less than 5:1. The third gaseous stream is fed as the feedstock for a gas fermentation unit to have increased stability and product selectivity.