Process for preparing desulfurizing and denitrating agents

• US 4,629,721 A
• Filed: 03/12/1986
• Issued: 12/16/1986
• Est. Priority Date: 03/13/1985
• Status: Expired due to Term

• Current Assignee: Hokkaido Electric Power Company Incorporated
• Original Assignee: Hokkaido Electric Power Company Incorporated
• Inventors: Ueno, Tutomu
• Primary Examiner(s): Shine, W. J.
• Application Number:
  US06/838,662
• Time in Patent Office: 279 Days
• Field of Search: 502/400, 502/407, 502/411, 502/415, 55/74
• US Class Current: 502/411
• CPC Class Codes: B01D 53/508 by treating the gases with solids
• CPC Class Codes: B01D 53/56 Nitrogen oxides B01D53/60 takes precedence
• CPC Class Codes: B01D 53/60 Simultaneously removing sulfur oxides and nitrogen oxides

Abstract

This invention relates to a preparation process of desulfurizing and denitrating agents for an off-gas produced upon combustion of a fuel such as coal or heavy oil.

The agent can be obtained by providing as first raw material(s) one or more materials capable of yielding calcium oxide and calcium sulfate, providing as second raw material(s) one or more materials capable of yielding silicon dioxide and aluminum oxide, mixing the first raw material(s) or a mixture of the first raw material(s) and either fractional or whole portion(s) of the second raw material(s) with water, subjecting the resultant aqueous mixture to wet-air aging at room temperature or to steam aging, and optionally subjecting the thus-aged mixture further to a heat treatment at a temperature of 30° C. or higher.

The desulfurizing and denitrating agents of this invention are prepared simply from readily-available raw materials such as cement, slag, coal ash, glass and fluidized-bed combustion ash and show high activity in both desulfurization and denitration. They are thus useful for the prevention of air pollution.

Claims

1. A process for preparing a desulfurizing and denitrating agent, which comprises providing as first raw material(s) one or more materials capable of yielding calcium oxide and calcium sulfate, providing as second raw material(s) one or more materials capable of yielding silicon dioxide and aluminum oxide, mixing the first raw material(s) or a mixture of the first raw material(s) and either fractional or whole portion(s) of the second raw material(s) with water, and then subjecting the resultant aqueous mixture to wet-air aging at room temperature or to steam aging.

2. A process for preparing a desulfurizing and denitrating agent, which comprises providing as first raw material(s) one or mor materials capable of yielding calcium oxide and calcium sulfate, providing as second raw material(s) one or more materials capable of yielding silicon dioxide and aluminum oxide, mixing the first raw material(s) or a mixture of the first raw material(s) and either fractional or whole portion(s) of the second raw materials with water, subjecting the resultant aqueous mixture to wet-air aging at room temperature or to steam aging, and then subjecting the thus-aged mixture to a heat treatment at a temperature of 30°

C. or higher.