Combustion Engineering, Inc.

Brown University

Electric Power Research Institute Incorporated

Arun K Mehta

Richard W Borio

Robert H Hurt

Xu Chen

Yuming Gao

Eric M Suuberg

Gilbert L Hale

Donald C Borio

Arnold L Tyler

Henry J Blaskowski

Carl R Bozzuto

Donald A Smith

Zinovy Plavnik

Hugh W Nelson

Prabhudas P Kantesaria

Eric M Suubert

Carbon-containing fly ash has been treated with optimum amounts of ozone. There is homogenous treatment of the fly ash with ozone and over saturation with ozone is avoided. In a further embodiment of the invention carbon, from various sources is oxygenated to be incorporated into concrete. The preferred oxygenating agent is ozone.

Ozone treatment of fly ash

A method for removing ammonia from fly ash employs water mist (a water fog) or a flowing warm humid air stream to rid the fly ash of ammonia. Ozone alone or with other co-oxidants such as hydrogen peroxide are also used to rid fly ash of ammonia.

Dry and semi-dry methods for removal of ammonia from fly ash

An impulse generator produces controlled pressure waves for removing ash deposits from heat exchangers in a boiler. The impulse generator has a fuel inlet, an air inlet, an ignitor, an outlet, and a control system for selectively and intermittently igniting the fuel and air to produce the pressure waves. In a first exemplary embodiment, the impulse generator includes a toroidal-shaped body with a tangential air inlet for inducing a helical swirling flow of the fuel and the air. In a second exemplary embodiment, the impulse generator includes a turbulizer with a corkscrew-shaped vane for inducing a helical swirling flow of the fuel and the air. In addition, an exemplary ash deposit removal method includes adjusting the fuel flow, airflow, ignition dwell time, and/or ignition interval time to selectively adjust the combustion mode between deflagrative and detonative combustion.

Impulse ash deposit removal system and method

Carbon-containing fly ash has been treated with optimum amounts of ozone. There is homogenous treatment of the fly ash with ozone and oversaturation with ozone is avoided.

An integrated method of removing alkali metal compounds from sulfur-bearing coal is disclosed. The coal is comminuted (4) and mixed (10) with water (8) to form a slurry (12). In the preferred embodiment, the slurry (12) is comingled with an SO.sub.2 -bearing gas (16) in a transport pipeline (52) to form an acidic slurry which dissolves the alkali compounds out of the coal. The slurry is then separated (22) into a solid portion (24) and a liquid portion (26), the solid portion (24) being combusted (34) to form the SO.sub.2 -bearing gas (16).

Integrated coal cleaning process

A conventional pulverized coal-fired furnace is supplied fuel at two different levels. The raw coal is classified into a stream of relatively pure coal ground to conventional fineness for burners at the lower level, and a stream of very finely divided coal with a large, heavy mineral content for burners at the higher level.

System and method for firing coal having a significant mineral content

A system receives raw coal which is routed through crushing, screening, pulverizing, classifying, and beneficiation stages with the de-mineralized fraction of the coal routed to a pulverized-coal-fired furnace, while the mineralized fraction is routed to a fluidized bed furnace.

Coal beneficiation/combustion system

A furnace in which fuel, such as pulverized coal, is burned, with the fuel and air being introduced into the furnace through tangential burners located in each of the four corners thereof and being directed tangentially to an imaginary circle in the center of the furnace. The invention will be described with pulverized coal, but is not limited to coal. Combustion gases from downstream of the furnace are recirculated back to the furnace, and are also introduced into the furnace from the four corners, in a tangential manner. The coal is introduced along with primary air to be directed at the smallest of a series of concentric imaginary circles; the recirculated gases are directed tangentially at a somewhat larger imaginary circle; and the secondary air is directed tangentially at a still larger imaginary circle.

Tangential firing system

A method of operating a pulverized coal furnace wherein the coal is introduced with minimal oxygen through an intermediate zone of the furnace which also has a relatively low oxygen content. The carbon particles are projected into an upstream portion of the furnace where secondary air is introduced to burn the carbon particles. The combustion products pass upwardly through the intermediate zone to a downstream zone where tertiary air is added to complete combustion.

Fuel firing method

The Air Quality Control System utilizes the reaction between nitrogen oxides and the sulfites and bisulfites which are produced as a slurry of lime/limestone absorbs sulfur dioxide from a mixture of gases to produce ammonia from the absorption of nitrogen oxides.

Method for removing sulfur and nitrogen compounds from a gas mixture

An entrained flow coal gasifier wherein a high temperature product gas stream is essentially formed by burning char with air. Additional char, formed by partial gasification of coal, is added immediately thereafter to obtain the gasification reaction. Fresh coal is thereafter supplied in a lower temperature region thereby obtaining the volatile components driven off at a relatively low temperature.

Entrained flow coal gasifier

Water is sprayed through a gas stream before it flows to an Air Quality Control System scrubber tank to absorb SO.sub.2 and produce a highly acidic liquid stream. The acid stream is mixed with a bleed stream from the AQCS cycle in a tank which will provide the residence time to complete the reaction of chemical in the bleed stream.

System for improved additive utilization in an air quality control system

A bowl mill for pulverizing coal, wherein two bowl surfaces are rotated on the same shaft. The raw crushed coal is pulverized in one of the bowls, and the pulverized coal therefrom is then transported in an air stream to a classifier from where the fines are carried on to the ultimate point of use, and the more coarse particles are discharged into the second bowl for further grinding.

Plural bowl mills in series

Air quality control system scrubs flue gas of SO.sub.2 and particulates with a slurry of lime/limestone and water. The contact between the slurry is in a centrifugal section which is the upper part of a tank in which the chemical action is completed and from which the slurry is recirculated to the contact section. The gas to be scrubbed is inserted into a circular path within the scrubbing section into which the slurry is sprayed. The treated gas is withdrawn from the circular path in heat exchange relationship with the incoming gas.

Growing community of inventors

Bloomfield, CT, United States of America

Arun K Mehta