Process and system for drying and heat treating materials

Abstract

This invention discloses systems and methods for conversion of high moisture waste materials to dry or low moisture products for recycle or reuse. The equipment systems comprise a gas turbine generator unit (preferred heat source), a dryer vessel and a processing unit, wherein the connection between the gas turbine and the dryer vessel directs substantially all the gas turbine exhaust into the dryer vessel and substantially precludes the introduction of air into the dryer vessel and wherein the processing unit forms the dried material from the dryer vessel into granules, pellets or other desired form for the final product. Optionally, the systems and methods further provide for processing ventilation air from manufacturing facilities to reduce emissions therefrom.

1 . A method for treatment of waste material feedstock comprising:
 operating a gas turbine generator to produce electricity and exhaust gases having a temperature greater than 700° F.;   contacting the exhaust gases having a temperature greater than 700° F. directly with waste material feedstock in a dryer vessel for a contact time sufficient to produce a dried material having a moisture content of less than about 20% by weight;   outletting the exhaust gases and the dried material from the dryer vessel through a dryer outlet;   conveying the exhaust gases and the dried material together through a dryer outlet conduit that extends from the dryer outlet to a solids/gas separator;   drawing the exhaust gases from the solids/gas separator using an air moving device in fluid communication with the solids/gas separator, wherein the air moving device also reduces backpressure in the dryer vessel by drawing the exhaust gases from the dryer vessel through the dryer outlet conduit to the solids/gas separator.   
   
   
       2 . A method according to  claim 1  wherein the exhaust gas contacting the waste material feedstock is at an initial temperature between about 1,100° F. and about 1,600° F. 
   
   
       3 . A method according to  claim 1  wherein the waste material feedstock comprises at least about 30% by weight moisture. 
   
   
       4 . A method according to  claim 1  further comprising the steps of granulating, pelletizing or prilling the dried material to produce a product suitable for conventional dry product handling, transport or use. 
   
   
       5 . A method for producing a dried material from an inorganic waste material feedstock comprising:
 operating a gas turbine generator to produce electricity and exhaust gases having a temperature greater than 700° F.;   contacting the exhaust gases having a temperature greater than 700° F. directly with waste material feedstock in a dryer vessel for a contact time sufficient to produce a dried inorganic material having a moisture content of less than about 20% by weight;   outletting the exhaust gases and the dried inorganic material from the dryer vessel through a dryer outlet;   conveying the exhaust gases and the dried inorganic material together through a dryer outlet conduit that extends from the dryer outlet to a solids/gas separator;   drawing the exhaust gases from the solids/gas separator using an air moving device in fluid communication with the solids/gas separator, wherein the air moving device also reduces backpressure in the dryer vessel by drawing the exhaust gases from the dryer vessel through the dryer outlet conduit to the solids/gas separator.   
   
   
       6 . A method according to  claim 5  wherein the exhaust gas contacting the waste material feedstock is at an initial temperature between about 1,100° F. and about 1,600° F. 
   
   
       7 . A method according to  claim 5  wherein the waste material feedstock comprises at least about 50% by weight moisture. 
   
   
       8 . A method according to  claim 5  further comprising the steps of granulating, pelletizing or prilling the dried material to produce a soil builder product suitable for conventional handling, transport or use. 
   
   
       9 . A method for producing a dried product from an inorganic waste material feedstock comprising:
 operating a gas turbine generator to produce electricity and exhaust gases;   contacting the exhaust gases with the waste material feedstock in a dryer vessel for a contact time sufficient to produce a dried inorganic material having a moisture content less than about 20% by weight;   outletting the exhaust gases and the dried inorganic material from the dryer vessel through a dryer outlet;   conveying the exhaust gases and the dried inorganic material together through a dryer outlet conduit that extends from the dryer outlet to a solids/gas separator;   drawing the exhaust gases from the solids/gas separator using an air moving device in fluid communication with the solids/gas separator, wherein the air moving device also reduces backpressure in the dryer vessel by drawing the exhaust gases from the dryer vessel through the dryer outlet conduit to the solids/gas separator; and   processing and forming the dried inorganic material into a granular, pellet or prill form of product suitable for conventional handling, transport or use.   
   
   
       10 . A method according to  claim 9  wherein the waste material feedstock comprises a moisture content of at least about 50% by weight. 
   
   
       11 . A method according to  claim 10  wherein the moisture content is at least about 70% by weight. 
   
   
       12 . A method according to  claim 9  wherein the dried inorganic material comprises a moisture content less than about 15% by weight. 
   
   
       13 . A method according to  claim 9  wherein the product comprises a moisture content less than about 10% by weight.