Systems and methods in accordance with the present invention provide for the efficient distillation of ethanol in an ethanol plant including a beer column. Heat is captured in the distillation process and utilized to drive operations in the ethanol plant.

A method for the purification of a raw gas stream by selective catalytic oxidation, in which organic and inorganic sulfur compounds, halogenated and non-halogenated volatile organic compounds are selectively oxidized without substantially oxidizing the lower hydrocarbons and the sulfur containing compounds present in the gas to sulfur trioxide and excess of oxygen is removed by oxidation of lower alcohols, ethers or hydrogen added to the raw gas stream upstream the catalytic oxidation.

Oxygen is removed from a gas feed such as a landfill gas, a digester gas or an industrial CO.sub.2 off-gas by heating the feed gas, optionally removing siloxanes and silanols from the heated feed gas, optionally removing part of the sulfur-containing compounds in the heated feed gas, injecting one or more reactants for oxygen conversion into the heated feed gas, carrying out a selective catalytic conversion of any or all of the volatile organic compounds (VOCs) present in the gas, including sulfur-containing compounds, chlorine-containing compounds and any of the reactants injected, in at least one suitable reactor, and cleaning the resulting oxygen-depleted gas. The reactants to be injected comprise one or more of H.sub.2, CO, ammonia, urea, methanol, ethanol and dimethyl ether (DME).

Certain aspects of natural gas liquid fractionation plant waste heat conversion to simultaneous power and cooling capacities using modified Goswami system can be implemented as a system. The system includes a waste heat recovery heat exchanger configured to heat a buffer fluid stream by exchange with a heat source in a natural gas liquid fractionation plant. The system includes a modified Goswami cycle energy conversion system including one or more first energy conversion system heat exchangers configured to heat a working fluid by exchange with the heated buffer fluid stream, a separator configured to receive the heated working fluid and to output a vapor stream of the working fluid and the liquid stream of the working fluid, a turbine and a generator, wherein the turbine and generator are configured to generate power by expansion of a first portion of the vapor stream of the working fluid, and a cooling subsystem including a cooling element configured to cool a process fluid stream from the natural gas liquid fractionation plant by exchange with a condensed second portion of the vapor stream of the working fluid.

A method and an integrated system for reducing CO.sub.2 emissions in industrial processes. The method and integrated system (100) capture carbon dioxide (CO.sub.2) gas from a first gas stream (104) with a chemical absorbent to produce a second gas stream (106) having a higher concentration of carbon monoxide (CO) gas and a lower concentration of CO.sub.2 gas as compared to first gas stream. The CO gas in the second gas stream is used to produce C.sub.5 to C.sub.20 hydrocarbons in an exothermic reaction (108) with hydrogen (H.sub.2) gas (138). At least a portion of the heat generated in the exothermic reaction is used to regenerate the chemical absorbent with the liberation of the CO.sub.2 gas (128) captured from the first gas stream. Heat captured during the exothermic reaction can, optionally, first be used to generate electricity, wherein the heat remaining after generating electricity is used to thermally regenerate the chemical absorbent.

The present disclosure provides systems and methods that combine direct capture of one or more moieties from a gaseous mixture with one or both of calcium oxide production and power production. The systems and methods can utilize combinations of a capture unit, a regeneration unit, a calcination unit, a slaking unit, a heat exchange unit, a separation unit, and a power production unit. The present disclosure provides the ability to remove carbon dioxide and other moieties from air or other gaseous mixtures in a truly carbon negative manner by utilizing electricity from a power production unit that is operated in a carbon neutral or carbon negative manner and simultaneously provide useful products, such as calcium oxide and calcium hydroxide.

A serial-rotor type high efficiency purification system includes a first rotor, a second rotor and an incinerator. The first rotor has a first adsorption zone and a first desorption zone. The first adsorption zone is adapted to adsorb VOCs and expel a first adsorption-treated air. The first desorption zone is adapted for the VOCs to be desorbed and to expel a first desorption-treated air. The second rotor has a second adsorption zone and a second desorption zone. The second adsorption zone is adapted to adsorb the VOCs within the first adsorption-treated air. The incinerator is adapted to incinerate the VOCs within the first desorption-treated air. The present invention is characterized in that the first adsorption-treated air can be treated again by the second rotor, such that the VOCs concentration of the second adsorption-treated air can be significantly reduced. High processing efficiency can thus be achieved.

The present invention relates generally to the field of emission control equipment for boilers, heaters, kilns, or other flue gas-, or combustion gas-, generating devices (e.g., those located at power plants, processing plants, etc.) and, in particular to a new and useful method and apparatus for reducing and/or eliminating various liquid discharges from one or more emission control equipment devices (e.g., one or more wet flue gas desulfurization (WFGD) units). In another embodiment, the method and apparatus of the present invention is designed to reduce and/or eliminate the amount of liquid waste that is discharged from a WFGD unit by subjecting the WFGD liquid waste to one or more drying processes, one or more spray dryer (or spray dry) absorber processes, and/or one or more spray dryer (or spray dry) evaporation processes.

In one aspect, an air contactor comprising an air inlet, an air outlet, a fan assembly to produce an airflow, a heat exchanger operable to transfer heat between a process fluid and the airflow, and an air pollutant capture system configured to selectively remove an air pollutant from the airflow. A controller has a fluid cooling and air pollutant capture mode wherein the controller controls the fan assembly to facilitate the heat exchanger transferring heat between the process fluid and the airflow and the air pollutant capture system removing the air pollutant from the airflow. The controller has a fluid cooling mode wherein the controller controls the fan assembly to facilitate the heat exchanger transferring heat between the process fluid and the airflow and the air pollutant capture system removing less of the air pollutant from the air.

Systems and methods for reducing the energy requirements for carbon dioxide capture are described. Heat from system processes, such as steam condensation and hot flue gas, is utilized to heat reflux liquid utilized in release of carbon dioxide from absorbent solvent.