United States Steel Corporation

William J Didycz

John Edward Aiken

Donald Glassman

Edward E Maier

George T Saniga

Stanley J Kerkentzes

Reactor and method for providing improved conversion of oxidizable pollutants from a waste gas stream by passing such a gas stream at a velocity of less than about 200 feet per minute through a chamber containing a thin catalyst bed capable of oxidizing the oxidizable pollutants and having a temperture rise from the inlet side to the outlet side of the bed of between about 50.degree. C. and about 400.degree. C. and a distributor plate located upstream and parallel to the bed. The distributor plate contains a plurality of openings such that the plate surface has a total open area of less than about 10% therein. In a preferred embodiment wherein a plurality of catalyst beds are provided, separate distributor plates are placed between the inlet for each bed and the bed itself.

Waste gas purification reactor and method

Systems and methods for directing waste gases to a by-pass conduit from a conduit to a waste gas purifier in response to signals indicating predetermined conditions which are harmful to the waste gas purifier to which the waste gases are normally directed while at the same time maintaining a substantially uniform pressure at the source of the waste gases. Preferably, the source of the waste gases is a scrubber unit for a maleic anhydride production unit. The waste gas purifier is preferably a catalytic oxidation unit for oxidizing hydrocarbons and carbon monoxide in the waste gases.

Waste gas purification systems and methods

Device and method for removing dissolved organic acids from entrained liquid droplets in a waste gas stream comprising (1) heating the liquid droplets in the waste gas stream to the vaporization temperature, and (2) contacting the waste gas stream with a collecting means whereby the dissolved organic acids are deposited on the means of evaporization of the liquid droplets to thereby produce the heated gas stream substantially free of the liquid droplets. Additionally, the invention preferably relates to a reactor and method additionally comprising the steps of (1) introducing the waste gas stream having the dissolved organic acids removed through an inlet into a chamber containing a catalyst bed for oxidizing the pollutants, (2) passing the waste gas stream through a distributor plate containing a multiplicity of holes located between the inlet and the catalyst bed in a manner such that the waste gas is substantially uniformly distributed over the catalyst bed, (3) passing the waste gas through the catalyst bed while maintaining the catalyst bed at a temperature sufficient to sustain catalytic oxidation of the oxidizable pollutants, and (4) withdrawing through an outlet of the chamber the waste gas stream which has passed through the catalyst bed. Additionally, it is preferred that the method includes the step of removing the deposited organic acids from the above mentioned collecting means. The collecting means is preferably in the form of a thin fin parallel tube heat exchanger.

A process is described for the removal of acid gases and ammonia from dilute aqueous solutions. This is achieved by two separate and successive distillations. In the first distillation, substantially all of the acid gases and free ammonia are removed. In the second distillation, substantially all of the fixed ammonia is removed. Exemplary aqueous solutions are waste waters from coke oven and coal conversion plants.

Process for separating acid gases and ammonia from dilute aqueous

Reactor for removing oxidizable pollutants from a waste gas stream which comprises (1) means for introducing the waste gas stream through an inlet into a chamber containing a substantially horizontal catalyst bed container means below the inlet, which container means is for containing a granular catalyst bed for oxidizing the pollutants and which container means comprises (a) support means for the catalyst bed which support means is permeable to the waste gas stream and covers substantially the entire horizontal cross section area of the chamber below the catalyst bed and has an outer edge adjacent to the chamber wall, (b) packing means to fit around the outer edge of the support means to prevent loss of catalyst between the edge of the support means and the wall of the chamber, (c) ledge means which provides a substantially horizontal support around the inside periphery of the chamber wall for leveling the catalyst bed and which ledge means also exerts substantial downward and outward pressure on the packing means to thereby tightly press the packing means against the support means and the wall of the chamber, (2) means for passing the waste gas stream through the catalyst bed while maintaining the catalyst bed at a temperature of between about 140.degree. C. and about 540.degree. C. and sufficient to sustain catalytic oxidation of the oxidizable pollutants; and (3) means for withdrawing through an outlet of the chamber the waste gas stream which has passed through the catalyst bed.

Waste gas purification reactor including packing holder and catalyst

A water purification process is described for the removal of ammonia and optionally one or more acid gases from waste waters such as coke-plant or coal conversion waste waters. The process involves adding lime to these waste waters in amounts sufficient to react with fixed ammonia salts present in the waste water and to enable substantially all of the ammonia to be evolved upon distillation, adding a threshold amount of a scale inhibitor compound chosen from the class of certain organic phosphonates and subjecting the thus treated waste water to distillation to remove substantially all of the ammonia and acid gases present from the waste water. Preferably, this process is achieved by two separate and successive distillations. In this preferred process, the first distillation substantially reduces the amount of the acid gases and free ammonia. In the second distillation, the amount of fixed ammonia is substantially reduced.

Process for separating ammonia and acid gases from waste waters

A water purification process is described for the removal of ammonia and optionally one or more acid gases from waste waters such as coke-plant or coal conversion waste waters. The process involves adding lime to these waste waters in amounts sufficient to react with fixed ammonia salts present in the waste water and to enable substantial amounts of the ammonia to be evolved upon distillation, adding a threshold amount of a scale inhibitor compound chosen from the class of certain organic phosphonates and subjecting the thus treated waste water to distillation to remove substantial amounts of the ammonia and acid gases present from the waste water. Preferably, this process is achieved by two separate and successive distillations. In this preferred process, the first distillation substantially reduces the amount of the acid gases and free ammonia and is conducted at a pH of more than 9. In the second distillation, the amount of fixed ammonia is substantially reduced. To conserve energy, the stripping vapors from the second distillation are reused as stripping vapors for the first distillation.

Growing community of inventors

Whitehall Borough, PA, United States of America

William J Didycz