A method for dual water scrubbing and an in-line dual water scrubber for gas cleaning onboard a vessel are disclosed. The in-line dual water scrubber includes a vertical extended body, a gas inlet, and a gas outlet. The gas inlet is underlying in the lower section of the extended body and the gas outlet is overlying in the upper section of the extended body. A first underlying scrubbing section, and a second scrubbing section in an upper section of the extended body are provided. One or more liquid collectors are arranged above one or more first scrubbing liquid sprayers. The liquid collector is arranged for collecting one or more second scrubbing liquid and for flow through of a vertical upwards flowing gas-flow from the inlet to the outlet.

The present invention relates to an advanced system for the removal of air pollutants from combustion and non-combustion processes that generate air pollutants that are regulated by environmental agencies. The pollutants include, but are not limited to, particulate matter; acid gases including sulphur dioxide, hydrogen chloride and hydrogen fluoride; metals such as mercury, dioxins, VOCs and reagents such as ammonia. The system collects and processes the polluted gas stream through two forms of wet method scrubbing technology. The gas is first passed through a wet scrubbing reactor capable of complete interaction between the gas and the selected liquid scrubbing reagent at one or more interfaces. The scrubbing medium is selected for its reactivity with the pollutants targeted in the process, its cost and impact on the environment. From the exit of the scrubbing reactor the gas is directed through a wet electrostatic precipitator to remove the remaining targeted pollutants to very high removal efficiency.

A gas inlet system for a wet gas scrubber includes a weir configured to deliver liquid to a scrubbing passage to wet the interior surface of the scrubbing vessel during operation of the gas inlet system. The weir include a weir duct and a weir trough extending at least partially around the weir duct to receive and at least partially fill with liquid during operation of the gas inlet system. The weir trough has an upper trough outlet in liquid communication with the upper weir duct inlet to deliver liquid from the weir trough into the upper weir duct inlet during operation of the gas inlet system. The weir trough also has a lower trough outlet below the upper trough outlet. The lower trough outlet is in liquid communication with the scrubbing passage to deliver liquid from the weir trough toward the scrubbing passage during operation of the gas inlet system.

A waste gas scrubbing tower includes a tower body unit, a filtration unit arranged in the tower body unit, a washing unit that introduces water from an external supply into the tower body unit. The tower body unit includes division boards that define a plurality of channels through which waste gas flows, the tower body unit including a waste gas inlet opening and a waste gas outlet opening. The filtration unit includes a plurality of filter members, which are arranged in the channels. The washing unit is operable to generate water mist curtains in the channels to wash the waste gas so that the waste gas that enters the waste gas scrubbing tower is subjected to multiple times of washing and filtration and purification.

Systems and methods are described for treating flue gas, for example from a coal fired power plant. The systems and methods include control of a wet flue gas desulfurization (WFGD) system to manage sulfite concentration in a slurry produced by the WFGD system. Oxygen is added to the slurry in an amount sufficient to produce a sulfite concentration in the slurry in the range of about 5 to 75 mg/L, an oxidation reduction potential in the range of about 100-250 mV, or both. The systems and methods also include the biological treatment to remove selenium from a liquid fraction of the slurry. The liquid fraction is treated in a biological reactor maintained under anoxic or anaerobic conditions to reduce its selenium concentration.

Methods, apparatus, and compositions for cleaning gas. The use of segmented multistage ammonia-based liquid spray with different oxidation potentials to remove sulfur compounds from gas. The use of different oxidation potentials may reduce unwanted ammonia slip.

An improved air scrubber has an improved, more efficient, more robust impeller and impeller housing for mixing incoming air with water, scrubbing the air with increased efficiency and lower mean time between failures. Also water flow through the system is improved to prevent loss of scrubbing performance and to reduce user workload. In addition to these improvements, the water intake system has been redesigned to use less water, prevent using too much water, and to prevent previously common errors that require users to drain water from the impeller housing.

System and methods for solder flux removal from a gas stream is disclosed. In one aspect, the system includes: a scrubber chamber having a gas inlet and a gas outlet through which the gas stream is introduced into and withdrawn from the scrubber chamber; at least one rinse agent delivery mechanism for introducing a rinse agent into the scrubber chamber for contact with the gas stream, the rinse agent being at a temperature for condensing a first portion of the flux from the gas stream; a condenser portion of the scrubber chamber containing the rinse agent for receiving the gas stream, the rinse agent being at a temperature for condensing a second portion of the flux in the gas stream; and a condensed flux removal apparatus adapted for removal from the scrubber chamber of at least a portion of the rinse agent and the flux which has condensed.

Provided is a dust collection method using a dust collection device. The dust collection device includes: a main body provided in a tubular shape; an exhaust tube provided so as to extend outside from midstream inside the main body through one end of the main body, the exhaust tube cooperating with a suction device to suck air inside the main body; a supply nozzle for supplying a liquid to inside of the main body; a recovery unit for recovering the liquid from the main body; and a pump for returning the liquid from the recovery unit to the supply nozzle. The dust collection method includes: a step of forming a rotating airflow by means of suction with the suction device, the rotating airflow progressing while spiraling along an inner wall surface of the main body; a step of supplying the liquid from the supply nozzle; a step of spreading out the liquid with the rotating airflow on the inner wall surface thereby to continuously form a liquid catcher, the liquid catcher rotating as a film of the liquid; and a step of separating smoke and/or dust to outside by centrifugal force due to the rotating airflow and capturing the smoke and/or dust with the liquid catcher, the smoke and/or dust being contained in air introduced to the inside of the main body.

Provided is a mist discharge device configured to discharge a mist trapped by a demister, in which the demister is disposed in a gas flow path allowing gas to flow from the lower side to the upper side in the vertical direction, has a lower side serving as an inlet side of the gas and an upper side serving as an outlet side of the gas, and is configured to trap the mist contained in the gas, and the mist discharge device includes a protrusion protruding downward from the inlet side of the demister. The protrusion is a plate-like member extending downward, and a plurality of the plate-like members are disposed to be horizontally spaced at predetermined intervals.