Energy-efficient yankee dryer hood system

• US 7,716,850 B2
• Filed: 04/26/2007
• Issued: 05/18/2010
• Est. Priority Date: 05/03/2006
• Status: Active Grant

• Current Assignee: GPCP IP Holdings LLC
• Original Assignee: Georgia-Pacific Consumer Products LP (KOCH Industries Incorporated)
• Inventors: Monore, Steven W., Hunter, Mark S., Deem, Charles E., Jadin, Timothy D., Barrie, Thomas H., Thomson, Scott M., Giannunzio, Scott L., Gardner, Steven M., Hodkiewicz, Donald J.
• Primary Examiner(s): GRAVINI, STEPHEN MICHAEL
• Application Number:
  US11/740,533
• Publication Number:
  US 20080034606A1
• Time in Patent Office: 1,118 Days
• Field of Search: 341/17, 341/24, 344/97, 162/359.1
• US Class Current: 34/117
• CPC Class Codes: D21F 5/044 using air hoods over the cylinders
• CPC Class Codes: D21F 5/181 on Yankee cylinder

Abstract

A paper machine configured as a swing machine capable of producing both light and heavy grades providing a Yankee hood split into a wet end half and a dry end half, at least one hood half being a flex-hood half wherein the supply for that half is capable of being run with either combustion heat or recycled heat and is capable of either recirculating the exhaust from the hood or discharging it to the atmosphere. The heater for the flex-hood half comprises both a primary combustion heat source and an indirect heat source capable of extracting by-product heat from another operation. The exhaust system for the flex hood half is capable of being run in either a straight through mode or in a recirculating mode.

Claims

1. A paper machine for manufacture of absorbent paper, comprising:

(a) a forming loop comprising a headbox and a translating foraminous support;

(b) a dryer section adapted to receive absorbent paper from said forming loop; and

(c) a reel adapted to receive absorbent paper from said dryer system;

wherein said dryer section comprises;

(i) a rotable Yankee dryer cylinder internally heated by steam;

(ii) a wet end hood section encompassing a portion of said Yankee dryer cylinder adjacent forming loop;

(iii) a dry end hood section encompassing a portion of said Yankee dryer cylinder adjacent said reel;

(iv) a dryer system exhaust;

(v) a wet end hood supply duct having a process heat exchanger, a first exhaust gas heat exchanger and a first burner disposed therein adapted to supply heated air to said wet end hood section;

(vi) a wet end hood exhaust duct adapted to receive air from said wet end hood section;

(vii) a wet end return duct adapted to supply air from said wet end hood exhaust duct to said wet end hood supply duct;

(viii) a first diverter damper system connected between said wet end hood exhaust duct and said wet end return duct, said first diverter damper being operable to selectively direct a quantity of moisture laden air exhausted from said wet end hood section to said wet end hood supply duct or alternatively to said dryer system exhaust through said first exhaust gas heat exchanger;

(ix) a dry end hood supply duct having a second process heat exchanger, a second exhaust gas heat exchanger and a second burner disposed therein adapted to supply heated air to said dry end hood section;

(x) a dry end hood exhaust duct adapted to receive air from said dry end hood section;

(xi) a dry end return duct adapted to deliver air from said dry end hood exhaust duct to said dry end hood supply duct; and

(xii) a second diverter damper system connected between said dry end hood supply duct and said dry end return duct, said second diverter damper system being operable to selectively direct air exhausted from said dry end hood section to said dry end hood supply duct or alternatively to said dryer system exhaust through said second exhaust gas heat exchanger.

2. A paper machine for manufacture of absorbent paper, comprising:

(a) a forming loop comprising a headbox and a translating foraminous support;

(b) a dryer section adapted to receive absorbent paper from said forming loop; and

(c) a reel adapted to receive absorbent paper from said dryer system;

wherein said dryer section comprises;

(i) a rotable Yankee dryer cylinder internally heated by steam;

(ii) a wet end hood section encompassing a portion of said Yankee dryer cylinder adjacent forming loop;

(iii) a dry end hood section encompassing a portion of said Yankee dryer cylinder adjacent said reel;

(iv) a dryer system exhaust;

(v) a wet end hood supply duct having a first burner disposed therein adapted to supply heated air to said wet end hood section;

(vi) a wet end hood exhaust duct adapted to receive moisture laden air from said wet end hood section;

(vii) a wet end return duct adapted to supply air from said wet end hood exhaust duct to said wet end hood supply duct;

(viii) a dry end hood supply duct having a second burner disposed therein adapted to supply heated air to said dry end hood section;

(ix) a dry end hood exhaust duct adapted to receive moisture laden air from said dry end hood section;

(x) a dry end return duct adapted to deliver air from said dry end hood exhaust duct to said dry end hood supply duct;

(xi) at least one of said supply ducts having an air to air heat exchanger disposed therein adapted for heating air supplied therethrough; and

(xii) a diverter damper system adapted to direct moisture laden gas exhausted from one of said hood halves to said heat exchanger and heat air supplied though one of said supply ducts.