US 8,579,999 B2 · Method of enhancing the quality of high-moisture materials using system heat sources

Abstract

The present invention harvests and utilizes fluidized bed drying technology and waste heat streams augmented by other available heat sources to dry feedstock or fuel. This method is useful in many industries, including coal-fired power plants. Coal is dried using the present invention before it goes to coal pulverizers and on to the furnace/boiler arrangement. Coal can be intercepted on current coal feed systems ahead of the pulverizers. Drying fuel, such as coal, is done to improve boiler efficiency and reduce emissions. A two-stage bed utilized in the process first “pre-dries and separates” the feed stream into desirable and undesirable feedstock. Then, it incrementally dries and segregates fluidizable and non-fluidizable material from the product stream. This is all completed in a low-temperature, open-air system. Elevation of fan room air temperature is also accomplished using waste heat, thereby making available to the plant system higher temperature media to enhance the feedstock drying process.

Claims33

Dependent claims

A method for improving a quality characteristic of a material through the application of at least two different waste heat sources, such material being for use within an industrial process operation, wherein such method comprises:

(a) providing a dryer bed for receiving the material and heat content from at least two different waste heat sources to be directed through the material;
(b) providing independent heat exchanger means each operatively connected to a waste heat source, a mixer box and the dryer bed to transfer a desired amount of heat content from each waste heat source to the mixer for use in the dryer bed;
and
(c) actively combining heat content contained within the at least two waste heat sources in the mixer box for delivering an aggregate heat content at or below 300° F. to the dryer bed;
(d) wherein “waste heat source” means a gaseous or liquid stream having an elevated heat content resulting from an operation of a process or piece of equipment separate from the heat treatment apparatus, such gaseous or liquid stream being used for the secondary purpose of providing heat content to the heat exchanger instead of being discarded.

2 more elements

Dependencies are inferred from the claim text.

Method of enhancing the quality of high-moisture materials using system heat sources

Life of this patent

Method of enhancing the quality of high-moisture materials using system heat sources

Life of this patent

Abstract

Claims33