Method and apparatus to produce synthesis gas via flash pyrolysis and gasification in a molten liquid

• Main Authors: ANDERSON MARK H, DIETENBERGER MARK A
• Format: Patent
• Language: English
• Published: 10.09.2013
• Subjects: CARBURETTING AIR OR OTHER GASES; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; COMPOUNDS THEREOF; FUELS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INORGANIC CHEMISTRY; LUBRICANTS; METALLURGY; NON-METALLIC ELEMENTS; PEAT; PERFORMING OPERATIONS; PETROLEUM, GAS OR COKE INDUSTRIES; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROMSOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLEGASES CONTAINING CARBON MONOXIDE; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; TECHNICAL GASES CONTAINING CARBON MONOXIDE; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; THEIR RELEVANT APPARATUS; TRANSPORTING

Disclosed are a method and a corresponding apparatus for converting a biomass reactant into synthesis gas. The method includes the steps of (1) heating biomass in a first molten liquid bath at a first temperature, wherein the first temperature is at least about 100° C., but less than the decomposition temperature of the biomass, wherein gas comprising water is evaporated and air is pressed from the biomass, thereby yielding dried biomass with minimal air content. (2) Recapturing the moisture evaporated from the biomass in step 1 for use in the process gas. (3) Heating the dried biomass in a second molten liquid bath at a second temperature, wherein the second temperature is sufficiently high to cause flash pyrolysis of the dried biomass, thereby yielding product gases, tar, and char. (4) Inserting recaptured steam into the process gas, which may optionally include external natural gas or hydrogen gas or recycled syngas for mixing and reforming with tar and non-condensable gases. (5) Further reacting the product gases, tar, and char with the process gas within a third molten liquid bath at a third temperature which is equal to or greater than the second temperature within the second molten liquid bath, thereby yielding high quality and relatively clean synthesis gas after a relatively long residence time needed for char gasification. A portion of the synthesis gas so formed is combusted to heat the first, second, and third molten liquid baths, unless external natural or hydrogen gas is available for this use.