Apparatus and methods for oxidizing an ammonia desulfurization solution. The apparatus may include an oxidation air system. The apparatus may include an oxidation tank. The apparatus may include in the tank, a gas-liquid dispersion enhancer. The enhancer may include a sieve plate layer that includes a sieve plate. The sieve plate layer may be one of a plurality of sieve plate layers. The plurality may include two or three sieve plate layers. The apparatus may include an oxidation enhancing device mated to the tank. The oxidation enhancing device may include an acoustic wave generating device. The oxidation enhancing device includes an ultrasonic wave generating device. The ultrasonic generating device may be configured to provide a sound intensity in the range 12 to 40 Watts/Liter. The ultrasonic generating device may be configured to provide to a liquid sound intensity in the range 12 to 40 Watts/Liter.

A process for producing ethanol from lignocellulosic biomass includes adding at least one of sulfur dioxide and sulfurous acid to the lignocellulosic biomass to provide an equivalent sulfur dioxide loading of at least 10 wt % sulfur dioxide to dry lignocellulosic biomass. The acidified lignocellulosic biomass is pretreated at a temperature above about 185° C. and for a pretreatment time less than about 10 minutes, to provide a pretreated biomass composition wherein the biomass is readily hydrolyzed by enzymes. Advantageously, sulfur dioxide from at least one of the flash stream and a stream derived from the flash is recovered and recycled back into the process.

A process for capturing carbon dioxide includes the steps of mixing a hydrogen stream and a feedstock stream to produce a mixed stream, wherein the feedstock stream includes hydrocarbons, reacting the hydrocarbons and the hydrogen in the primary reactor of the hydroprocessing unit to produce a hydroprocessing product stream and a carbon dioxide stream, wherein the hydroprocessing product stream includes light products, wherein the hydroprocessing unit is further configured to produce ammonium bisulfide, collecting the ammonium bisulfide in the water to produce a sour water, processing the sour water in the waste water unit to produce an ammonia stream, a hydrogen sulfide stream, and a stripped water stream, introducing the ammonia stream to a carbon dioxide recovery system, and separating carbon dioxide from the carbon dioxide stream using the ammonia in the ammonia stream to produce a carbon dioxide product.

The invention discloses a method for in-situ extracting a reduced carbon dioxide product or product mixture in an electrochemical cell, and the use of a three-compartment electrochemical cell for in-situ extraction of organic carboxylic acids such as formic acid, acetic acid, oxalic acid, glycolic acid, tartaric acid, malonic acid, propionic acid, glyoxylic acid, and/or salts thereof for commercial use.

The method of the invention comprises introducing carbon dioxide-rich absorbent into a cathode compartment of an electrochemical cell, applying an electrical potential between an anode and a cathode in the electrochemical cell sufficient for the cathode to reduce carbon dioxide into a reduced carbon dioxide product of product mixture in the carbon dioxide-rich absorbent, thereby providing a carbon dioxide-poor absorbent, collecting reduced carbon dioxide product or product mixture via in-situ extraction into an acidic environment, and wherein the anode is separated from the cathode by more than one separator.

Methods of sequestering carbon dioxide (CO.sub.2) are provided. Aspects of the methods include contacting an aqueous capture ammonia with a gaseous source of CO.sub.2 under conditions sufficient to produce an aqueous ammonium carbonate. The aqueous ammonium carbonate is then combined with a cation source under conditions sufficient to produce a solid CO.sub.2 sequestering carbonate and an aqueous ammonium salt. The aqueous capture ammonia is then regenerated from the from the aqueous ammonium salt. Also provided are systems configured for carrying out the methods.

The present invention relates to processes and systems for ammonia recovery and/or acid-gas separation. In some embodiments, a system for acid gas separation may be integrated with an ammonia abatement cycle employing a high temperature absorber. In some embodiments, a system for acid gas separation may employ a higher temperature absorber due to the lower energy consumption and cost of the integrated ammonia abatement cycle. Advantageously, heat may be recovered from the absorber to power at least a portion of any acid gas desorption in the process. Reverse osmosis or other membranes may be employed.

A vehicle CO.sub.2 capture and utilization system includes a concrete mixer vehicle and a vehicle exhaust capture system. The concrete mixer vehicle comprises a vehicle exhaust and a mixer tank. The vehicle exhaust capture system is located onboard the concrete mixer vehicle. Additionally, the vehicle exhaust capture system includes one or more fluid pathways that fluidly couple the vehicle exhaust and the mixer tank.

A process to treat/clean a gas, containing SO.sub.2, CO.sub.2 and O.sub.2 comprising the steps of: bringing the gas in contact with an activated carbon catalyst, converting SO.sub.2 to SO.sub.3/H.sub.2SO.sub.4 on the activated carbon catalyst, washing the SO.sub.3/H.sub.2SO.sub.4 from the activated carbon catalyst to obtain a sulfuric acid solution and a SO.sub.2 depleted gas; bringing the SO.sub.2 depleted gas in contact with an aqueous ammonia solution wherein CO.sub.2 is converted to obtain a SO.sub.2 and CO.sub.2 depleted gas containing ammonia; and bringing the SO.sub.2 and CO.sub.2 depleted gas containing ammonia in contact with the sulfuric acid solution obtained in step a. to form a solution containing ammonium sulfate and a treated, clean gas.

The present invention relates to a process and contactor vessel in which gas and liquid contact occurs to facilitate mass transfer therebetween. In one embodiment, the process includes a fluidised bed including mobile inert primary objects and secondary particles that facilitate turbulent mixing and enhanced gas/liquid surface area in the contactor.

A method for recovering ammoniacal nitrogen, in the form of ammonium carbonate and/or ammonium bicarbonate, from an ammoniacal nitrogen-containing vapor that comprises introducing said vapor into at least one pressurizable ammonia scrubbing vessel containing water, simultaneously introducing a carbon dioxide-containing vapor into at least one pressurizable carbon dioxide scrubbing vessel containing water, and simultaneously pumping the solutions created in said scrubbers via hydrologic connections between said scrubbers to mix the solution to create an ammonium carbonate and/or ammonium bicarbonate containing mixture, all while maintaining independent and unmixed vapor streams throughout the entire process. The method further involves recovering ammonium carbonate and/or ammonium bicarbonate from the mixture for further use.