The invention relates to a plant for generating negative emissions of CO.sub.2. The plant 100 comprises a gasifier 110, a lime kiln 130, a separator 150, and a CO.sub.2 permanent storage 170. The gasifier is suitable for receiving as input a fuel 111 and for producing as output a high-temperature syngas flow 114. The lime kiln is suitable for receiving as input carbonate mineral 131 and the high-temperature syngas flow, the lime kiln being further suitable for producing an oxide 134 and for releasing as output a flow of syngas 133 enriched with CO.sub.2. The separator is suitable for receiving as input a gas flow containing CO.sub.2 and for treating it so as to separately provide at least CO.sub.2 151. The CO.sub.2 permanent storage is suitable for enclosing along time the CO.sub.2. The invention also relates to a method for generating negative emissions of CO.sub.2.

The present disclosure relates to a method of thermal treatment of air-dispersible raw material, especially cement raw meal and/or mineral products, wherein the raw material is introduced into a conduit through which hot gases flow and is subjected to thermal treatment by the hot gases and/or the radiant heat in the conduit, fuel is at least partly converted in a treatment region, and the heat generated in the treatment region is supplied at least partly to the conduit, and an oxygen-rich gas is introduced into the treatment region, wherein the oxygen content in the hot gas and/or the gas temperature is ascertained and the amount of oxygen introduced into the treatment region is adjusted by open-loop or closed-loop control depending on the temperature ascertained and/or the oxygen content.

This invention relates to manufacturing briquettes, pellets and shapes from recycled asphaltic limestone powder derived from waste residential roofing products. Briquettes and pellets are manufactured through a densification process at varying temperatures, creating recycled asphalt pellets, asphalt limestone pellets and bio mass and coal fines briquettes. Various shapes, including curbs and posts, are manufactured through heat and pressure in molds. Seawalls, walkways and wall panels are manufactured by blending asphaltic limestone powders with polymer resins and extruded or pultruded into shapes.

The disclosure generally provides a modification of a calcination process of lime bearing sludge in such a way that the flue gas generated by the calcination process contains primarily carbon dioxide and water vapor along with only minor amounts of other gaseous species. Such a flue gas can be treated by standard industrial gas scrubbing and purification processes to remove residual particulate solids, to condense and remove the water vapor as liquid water, and further treatment to produce essentially pure carbon dioxide. The resulting product may be used for purposes that do not involve a net emission of carbon dioxide to the atmosphere, thereby reducing environmental harm. Such purified carbon dioxide may be used in industry for enhanced oil recovery (EOR) processes, synthetic fuels production, carbonated beverage production, pharmaceutical production, or other beneficial uses.

The present disclosure relates to a decarbonation process of carbonated materials, in particular limestone and dolomitic limestone, with CO.sub.2 recovery in a multi-shaft vertical kiln (MSVK) comprising a first and a second shaft with preheating, heating and cooling zones and a cross-over channel between each shaft. The method includes alternately heating carbonated materials by a combustion of at least one fuel with at least one comburent, up to a temperature range in which carbon dioxide of the carbonated materials is released, the combustion of the fuel and the decarbonation generating an exhaust gas. Decarbonated materials are cooled in the cooling zones with one or more cooling streams. The process further includes extracting the exhaust gas from the multi-shaft vertical kiln and feeding a buffer with the extracted exhaust gas.

The present disclosure relates to a decarbonation process of carbonated materials, in particular limestone and dolomitic limestone, with CO.sub.2 recovery in a multi-shaft vertical kiln (MSVK) comprising a first and a second shaft with preheating, heating and cooling zones and a cross-over channel between each shaft. The method includes alternately heating carbonated materials by a combustion of at least one fuel with at least one comburent, up to a temperature range in which carbon dioxide of the carbonated materials is released, the combustion of the fuel and the decarbonation generating an exhaust gas. Decarbonated materials are cooled in the cooling zones with one or more cooling streams. The process further includes extracting the exhaust gas from the multi-shaft vertical kiln and feeding a buffer with the extracted exhaust gas.

Process for operating a cement or lime plant comprising a cement or lime kiln and a calciner, wherein heat is generated by combustion of a fuel in the kiln and/or calciner, wherein a gas fed to the kiln and the calciner or to the calciner for combustion of the fuel contains an oxygen rich exhaust gas from a bioreactor containing photoautotrophic organisms and wherein the plant is preferably operated in the oxyfuel mode by using exhaust gas from the kiln and/or calciner together with the oxygen from the bioreactor as the gas fed to the kiln and/or calciner for combustion of the fuel.

A method of utilizing lignin-containing material separated from spent kraft pulping liquor including: acidifying the liquor to a pH not less than seven thereby precipitating solid particles, separating precipitated solid particles from the accompanying liquid, and subjecting the separated precipitated solid particles to a washing process in which: the separated precipitated solid particles are washed with an aqueous medium or aqueous media in one or more washing steps, in each one of the washing steps, the aqueous washing medium contains, in a dissolved form, significant amounts of one or more added sodium salts, and a combined concentration of the added sodium salts in the washing medium in each of the washing step exceeds three percent by weight; and utilizing as fuel in a lime kiln at least part of the washed lignin-containing material is utilized as fuel in a lime kiln of a pulp mill.

This invention discloses a calcination process to produce high purity CO.sub.2 from solids containing CaCO.sub.3 which operates cyclically and continuously on the solids, arranged in a packed or a moving bed, and wherein each cycle comprises a first step where the combustion at atmospheric pressure of a fuel in the bed of solids containing CaCO.sub.3 heats them up to 800-900? C. and a second step wherein a vacuum pressure between 0.05 and 0.5 atm is applied to extract pure CO.sub.2 from the solids containing CaCO.sub.3 while cooling them by 30-200? C. Said combustion can be carried out directly with air, oxygen enriched air or O.sub.2/CO.sub.2 mixtures when the process is applied to the calcination of a continuous flow of limestone in a moving bed shaft kiln. The process is also applied to calcine CaCO.sub.3 formed in reversible calcium looping processes comprising a carbonation reaction step to form CaCO.sub.3 from CaO.

Solid fuel in the form of particles is supplied to a pyrolyzer, and pyrolysis conditions are maintained in the pyrolyzer for separating condensable gaseous substances from the fuel. Heat required by the pyrolysis conditions is supplied at least partly with solid fluidized bed material which passes through the pyrolyzer simultaneously as it is fluidized by fluidizing gas in the pyrolyzer. Condensable gaseous substances separated from the fuel are conveyed from the pyrolyzer to a condenser, in which they are separated as so-called pyrolysis oil in liquid form, and solid fluidized bed material taken from the pyrolyzer and containing combustible pyrolysis residue originating from the fuel is circulated through a gasifier, in which product gas, which is burnt in a boiler or a kiln, is formed from the pyrolysis residue.