Energy-efficient gasification-based multi-generation apparatus, facilities, or systems, and methods of modifying existing gasification-based multi-generation apparatus and the various conventional thermal coupling arrangements, are provided. An exemplary gasification-based multi-generation apparatus includes a gasification system configured to generate the raw syngas feed from a carbon-based feedstock. The gasification system includes a gasification plant or facility, a sour water stripping plant or facility comprising a sour water stripper, a gasification reactor, and a gasification system energy management system. The gasification system energy management system comprises a third gasification system process-to-process heat exchanger unit positioned to receive a wastewater bottom stream from the sour water stripper and to receive at least a portion of an oxygen feed to the gasification reactor to provide heat energy to the at least a second portion of the oxygen feed to the gasification reactor and to cool the wastewater bottom stream from the sour water stripper. The sour water stripping plant or facility is integrated into the gasification plant or facility through at least the wastewater bottom stream from the sour water stripper.

Energy-efficient gasification-based multi-generation apparatus, facilities, or systems, and methods of modifying existing gasification-based multi-generation apparatus and the various conventional thermal coupling arrangements, are provided. Apparatus for managing waste heat recovery through integration of a gasification-based multi-generation facility or other multi-generation system with a hydrocarbon refining facility or other hydrocarbon refining system and methods of providing the respective integration are also provided. An exemplary apparatus includes an integrated site energy management system configured according to one or more process-based thermal coupling schemes comprising one or more thermal coupling arrangements between a gasification-based multi-generation system or facility and a hydrocarbon refining system or facility. The gasification-based multi-generation system or facility can include an acid gas removal system or plant configured to remove acidic contaminants from a raw syngas feed to thereby provide a treated syngas feed, the acid gas removal system or plant containing a separation section including a solvent regenerator, and a gasification system configured to generate the raw syngas feed from a carbon-based feedstock. The hydrocarbon refining system or facility can include an aromatics system or plant containing a xylene products separation section including one or more of the following: an Extract column and a Raffinate column. The integrated site energy management system can include a hot-water system extending between the separation section of the acid gas removal system or plant and the xylene products separation section of the aromatics system or plant, and a plurality of added heat exchanger units providing various advanced thermal coupling arrangements.

A method for converting a feedstock comprising solid hydrocarbons to a sweet synthesis gas, involving the steps a. gasifying said feedstock in the presence of steam, an oxygen rich gas and an amount of sour process gas to form a raw synthesis gas optionally comprising tar, b. optionally conditioning said raw synthesis gas to a sour shift feed gas, c. contacting said sour shift feed gas with a sulfided material catalytically active in the water gas shift process for providing a sour hydrogen enriched synthesis gas, d. separating H.sub.2S and CO.sub.2 from said sour hydrogen enriched synthesis gas, for providing said sour recycle gas and a sweet hydrogen enriched synthesis gas.

The present invention relates to a method for purifying a tar containing gas stream. The method comprises the steps of: a) contacting a tar containing gas stream with a washing liquid in a washing unit to obtain a tar containing washing liquid and a purified gas stream; b) adding an extractant to the tar containing washing liquid to obtain an extraction liquid comprising a tar containing extractant and a regenerated washing liquid; c) cooling the extraction liquid; d) after cooling, separating the tar containing extractant from the regenerated washing liquid, and e) recirculating the regenerated washing liquid to the washing unit.

A process for producing products from biomass comprises pyrolysing biomass at a selected temperature and producing a bio-syngas, processing bio-syngas from pyrolysis step (a) to remove condensable constituents from the bio-syngas, and processing the non-condensable bio-syngas from bio-syngas processing step (b) and producing one or more than one product, such as bio-fuels, bio-chemicals, bio-solvents and bio-plastics.