Process for removal of carbon dioxide from combustion gases

A process for purifying gases comprising carbon oxides comprising:

• washing the gases with an aqueous solution comprising an alkali carbonate or alkaline earth carbonate, whereby alkali or alkaline earth bicarbonates are formed as a solution or in solid form of precipitated crystals in the aqueous solution through absorption of carbon dioxide,
• passing the gases comprising carbon dioxide into the bottom section of a device for purifying gases comprising carbon oxides, the device comprising a container in the form of a cylinder with a gas inlet in a bottom region and a gas outlet in an upper region for output of purified gas, the container further comprising an aqueous solution inlet and an aqueous solution outlet for spent aqueous solution, wherein the container internally does not include stream baffles for the aqueous solution so that the gases and the aqueous solution can intermingle freely, and wherein the container internally includes one or more gas-impenetrable plates without current baffles and with a central hole for gas passage, and wherein a stirring device having one or more rotatable discs is mounted above the central hole of the one or more gas-impenetrable plates, said one or more rotatable discs being rotatably and centrally disposed over the one or more gas-impenetrable plates and wherein at least one of the one or more rotatable discs comprises at least one peripheral sector comprising a netting material for improved mixing of the gases and the aqueous solution in a formed foam when at least one of the one or more rotatable discs are rotating during intermingling of the gases and the aqueous solution;
• evacuating purified gas at the upper region of the device, and
• stirring the aqueous solution in the device to mix the gases and the aqueous solution to form bicarbonates as a solution or as crystals in the aqueous solution through absorption of carbon dioxide, from which aqueous solution an alkali or alkaline earth carbonate solution is derivable, by extraction of CO2 therefrom, for reuse.

A process for purifying combustion gases comprising carbon oxides, comprising the acts of:

• washing the combustion gases with an aqueous solution comprising an alkali carbonate or an alkaline earth carbonate, whereby alkali or alkaline earth bicarbonates are formed as a solution or in solid form of precipitated crystals in the aqueous solution through absorption of carbon dioxide, wherein the combustion gases comprising carbon oxides are passed into the bottom section of a device for purifying combustion gases comprising carbon oxides, the device comprising a container in the form of a cylinder with a gas inlet in a bottom region and a gas outlet in an upper region for output of purified gas, the container further comprising an aqueous solution inlet and an aqueous solution outlet for spent aqueous solution, wherein the container internally does not include stream baffles for the aqueous solution so that the combustion gases and the aqueous solution can intermingle freely, and wherein the container internally includes one or more gas-impenetrable plates without current baffles and with a central hole for gas passage, and wherein a stirring device having one or more rotatable discs is mounted above the central hole of the one or more gas-impenetrable plates, said one or more rotatable discs being rotatably and centrally disposed over the gas-impenetrable plates and wherein at least one of the one or more rotatable discs comprises at least one peripheral sector comprising a netting material for improved mixing of the combustion gases and the aqueous solution in a formed foam when at least one of the one or more rotatable discs are rotating-during intermingling of the combustion gases and the aqueous solution;
• evacuating purified gas at the upper region of the device,
• stirring the aqueous solution in the device to mix the combustion gases and the aqueous solution, and
• passing the spent aqueous solution from the container to a sedimentation device for separation of fluid and solids to form a precipitate;
• passing the precipitate to a filter unit for separation of the precipitate into solids and a filtrate;
• discharging the solids, comprising alkali carbonate or alkaline earth carbonate, from a first outlet of the filter unit;
• discharging the filtrate, from a second outlet of the filter unit, to a stirring tank comprising a stirring device;
• adding carbonate to the filtrate in the stirring tank to form an aqueous solution comprising carbonate;
• and
• passing the aqueous solution comprising carbonate from the stirring tank to the cylinder's aqueous solution inlet.