Pelletizer with moisture control system

• US 4,721,448 A
• Filed: 12/19/1985
• Issued: 01/26/1988
• Est. Priority Date: 12/19/1985
• Status: Expired due to Term

• Current Assignee: Coors Global Properties, Inc. (Molson Coors Beverage Co.)
• Original Assignee: Adolph Coors Company (Molson Coors Beverage Co.)
• Inventors: Hull, Marlin B., Irish, Mark R.
• Primary Examiner(s): Woo, Jay H.
• Assistant Examiner(s): Housel, James C.
• Application Number:
  US06/811,006
• Time in Patent Office: 768 Days
• Field of Search: 425/143, 425/144, 425/135, 425/DIG. 230, 425/173, 425/174.4, 425/209, 425/404, 364/183, 364/468, 364/469, 364/471, 364/476, 364/502, 99/487, 99/493, 99/517, 366/152, 366/158, 366/168, 264/40.1, 264/40.2, 264/40.6, 264/22, 264/142
• US Class Current: 425/144
• CPC Class Codes: A23K 10/38 from distillers' or brewers' waste
• CPC Class Codes: A23K 40/10 by agglomeration; by granulation, e.g. making powders
• CPC Class Codes: A23K 40/20 by moulding, e.g. making cakes or briquettes
• CPC Class Codes: A23K 40/25 by extrusion
• CPC Class Codes: A23K 50/10 for ruminants
• CPC Class Codes: A23N 17/005 for shaping by moulding, extrusion, pressing, e.g. pellet-mills processes A23K40/00; presses in general B30B
• CPC Class Codes: B30B 11/005 Control arrangements
• CPC Class Codes: B30B 11/202 Ring constructions
• CPC Class Codes: B30B 11/221 extrusion dies
• CPC Class Codes: Y02P 60/87 Re-use of by-products of food processing for fodder production
• CPC Class Codes: Y10S 425/23 Hay wafering or pelletizing means

Abstract

A moisture control system is provided for a pelletizing process wherein the moisture content of the pellets leaving the pelletizing process is constantly monitored and differences between the measured moisture content of the pellets and a set point indicating the desired moisture content of the pellets are used to regulate variable process controls in the pelletizing process so that the pellets leaving the pelletizing process will have the proper moisture content. Also, a system for protecting a viewing window of an instrument from contaminants is provided.

Claims

1. A moisture control system for use in a pelletizing process comprising:

holding means for holding a continuous supply of dry ingredients;

means for transferring at variable rates portions of said dry ingredients to a mixer-conditioner;

means for supplying a fluid at variable rates to said mixer-conditioner;

means for supplying steam at variable rates to said mixer-conditioner;

means in said mixer-conditioner for mixing said dry ingredients, said fluid and said steam to form a granular material;

means for feeding said granular material to a mill;

means for measuring the moisture content of said granular material as it passes from said mixer conditioner to said means for feeding said granular material to said mill;

means for generating a signal representative of said moisture content of said granular material;

means for transmitting said signal of said moisture content of said granular material to a granular moisture controller;

means in said granular moisture controller for comparing said signal of said moisture content of said granular material to a set point indicating a desired moisture content for said granular material and for performing a calculation thereon to produce a calculated set point signal;

means for transmitting said calculated set point signal to a fluid flow controller;

means in said fluid flow controller responsive to said calculated set point signal from said granular moisture controller to vary the rate of supply of said fluid so as to vary the amount of said fluid being supplied to said mixer-conditioner;

means for sensing the temperature of said granular material as it passes from said mixer-conditioner to said means for feeding said granular material to said mill;

means for generating a signal reresentative of said temperature;

means for transmitting said signal to a temperature controller;

means in said temperature controller for comparing said signal to a set point indicating a desired temperature for said granular material and for performing a calculation thereon to produce a control variable signal; and

means in said temperature controller responsive to said control variable signal to vary the rate at which said steam is being supplied so as to vary the amount of said steam being supplied to said mixer-conditioner.

6. A system as in claim 1 and further comprising:

means in said temperature controller for performing a calculation on said calculated set point signal from said temperature controller to produce a control signal representative of the amount of steam condensate resulting from said change in the rate at which said steam is being supplied and for transmitting said control signal to said fluid flow controller; and

means in said fluid controller responsive to said control signal to vary the rate of supply of said fluid so as to vary the amount of said fluid being supplied to said mixer-conditioner.

2. A moisture control system for use in a pelletizing process comprising:

holding means for holding a continuous supply of dry ingredients;

means for transferring at variable rates portions of said dry ingredients to a mixer-conditioner;

means for supplying a fluid at variable rates to said mixer-conditioner;

means for supplying steam at variable rates to said mixer-conditioner;

means in said mixer-conditioner for mixing said dry ingredients, said fluid and said steam to form a granular material;

means for feeding said granular material to a mill;

means for measuring the moisture content of said granular material as it passes from said mixer conditioner to said means for feeding said granular material to said mill;

means for generating a signal representative of said moisture content of said granular material;

means for transmitting said signal of said moisture content of said granular material to a granular moisture controller;

means in sid granular moisture controller for comparing said signal of said moisture content of said granular material to a set point indicating a desired mositure content for said granular material and for performing a calculation thereon to produce a calculated set point signal;

means for transmitting said calculated set point signal to a fluid flow controller;

means in said fluid flow controller responsive to said calculated set point signal from said granular moisture controller to vary the rate of supply of said fluid so as to vary the amount of said fluid being supplied to said mixer-conditioner;

means in said mill for forming said granular material into pellets;

means for feeding said pellets into a shaker-cooler;

a hopper in said shaker-cooler through which said pellets pass to a discharge conveyor;

means for measuring the moisture content of said pellets in said hopper;

means for generating a signal representative of said moisture content of said pellets in said hopper;

means for transmitting said signal representative of said moisture content of said pellets in said hopper to a pellet moisture controller;

4. A system as in claim 2 and further comprising:

means for sensing the temperature of said granular material as it passes from said mixer-conditioner to said means for feeding said granular material to said mill;

means for generating a signal representative of said temperature;

means for transmitting said signal to a temperature controller;

means in said temperature controller for comparing said signal to a set point indicating a desired temperature for said granular material and for performing a calculation thereon to produce a control variable signal; and

means in said temperature controller responsive to said control variable signal to vary the rate at which said steam is being supplied so as to vary the amount of said steam being supplied to said mixer-conditioner.

3. means in said pellet moisture conroller for comparing said signal representative of said moisture content of said pellets in said hopper with a set point indicating a desired moisture content for said pellets in said hopper and for performing a calculation thereon to produce a calculated set point signal;

means for transmitting said calculated set point signal from said pellet moisture controller to said granular moisture controller;

means in said granular moisture controller responsive to said calculated set point signal from said pellet moisture controller to change said set point of said desired moisture content for said granular material to a new set point.

5. A system as in claim 3 and further comprising:

means in said temperature controller for performing a calculation on said control variable signal to produce a control signal representative of the amount of steam condensate resulting from said change in the rate at which said steam is being supplied and for transmitting said control signal to said fluid flow controller; and

means in said fluid flow controller responsive to said control signal to vary the rate of supply of said fluid so as to vary the amount of said fluid being supplied to said mixer-conditioner.