Secondary air injection

About: Secondary air injection is a research topic. Over the lifetime, 11452 publications have been published within this topic receiving 112147 citations.

Cleaning exhaust gases from combustion installations

Abstract: In a process for cleaning the exhaust gases from combustion installations, a dilute urea solution prepared in a reagent tank (20) is introduced into the hot exhaust gas flow (30) of differing concentrations and is finely sprayed in the direction of the exhaust gas flow. After decomposition of the urea in a pyrolysation channel (14), the exhaust gas flow (30) is homogeneously mixed in-line by a mixer located in a mixing channel (16). In a subsequent in-line reaction channel (18), the reducible exhaust gas constituents are converted into non-toxic gases in at least one selective reduction catalyst which does not contain zeolite (36), then, dependent on the installation, the oxidizable exhaust gas components are converted into non-toxic gases without reagent in at least one oxidation catalyst (38) to produce a virtually complete reaction. A dual substance nozzle appliance (26) opening into the pyrolysation channel (14) comprises a reversing valve (88) for the working and blowing out position, a casing tube (24) for the compressed air, located in the area of the exhaust gas flow ( 30), a urea conductor carried at a distance in the casing tube (24) and a nozzle for fine spraying of the dilute urea solution.

Process for removing nox and sox from exhaust gas

Abstract: Exhaust gases containing oxides of nitrogen and sulfur from a fired process heater, a fossil fuel fired boiler, or a chemical process are diverted from a stack prior to admission to the atmosphere through a duct system containing heat exchangers that reduce the exhaust gas from an elevated temperature, if any, to about ambient temperature. Any heat extracted from the exhaust gas may be transferred to the boiler feed water which would serve to reduce the energy cost of operating a boiler. Once the exhaust gas is cooled to about ambient temperature, the gas is then mixed with an oxidant, such as ozone, at a preselected molar ratio to transform the oxides to higher orders of nitrogen and sulfur oxides to increase the absorbability of the nitrogen and sulfur oxides in a reagent solution. The reagent absorbs the oxidized contaminants from the exhaust gas. The oxides are transformed to dilute acids which are then neutralized to form salts that are acceptable for discharge to a municipal waste water treatment plant. The treated exhaust gas is then emitted from an exhaust stack containing contaminants at a level meeting air quality standards. Additionally any heat recovered from the exhaust gas can be used to lower operating costs.

Dual path EGR system and methods

Abstract: An internal combustion engine system, dual loop EGR system and method is provided, with a high pressure EGR loop, controlled by a control valve, in fluidic connection with the exhaust outlet of the exhaust manifold and the air inlet of the intake manifold, and a low pressure EGR loop, wherein exhaust, in proportions controlled by a control valve, enters a compressor from a point downstream of an exhaust emissions controller, together with fresh air, the low pressure EGR loop being in fluidic connection with an output of the compressor and the air inlet of the intake manifold.