US20040011484A1 - Method of producing energy at a pulp mill - Google Patents

Method of producing energy at a pulp mill Download PDF

Info

Publication number
US20040011484A1
US20040011484A1 US10/423,052 US42305203A US2004011484A1 US 20040011484 A1 US20040011484 A1 US 20040011484A1 US 42305203 A US42305203 A US 42305203A US 2004011484 A1 US2004011484 A1 US 2004011484A1
Authority
US
United States
Prior art keywords
recited
boiler
recovery boiler
flue gases
combustible gas
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/423,052
Other languages
English (en)
Inventor
Kari Saviharju
Jorma Simonen
Olli Arpalahti
Lasse Koivisto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Andritz Oy
Original Assignee
Andritz Oy
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=29420526&utm_source=***_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US20040011484(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Andritz Oy filed Critical Andritz Oy
Priority to US10/423,052 priority Critical patent/US20040011484A1/en
Assigned to ANDRITZ OY reassignment ANDRITZ OY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KOIVISTO, LASSE, SIMONEN, JORMA, ARPALAHTI, OLLI, SAVIHARJU, KARI
Publication of US20040011484A1 publication Critical patent/US20040011484A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
    • D21C11/00—Regeneration of pulp liquors or effluent waste waters
    • D21C11/06—Treatment of pulp gases; Recovery of the heat content of the gases; Treatment of gases arising from various sources in pulp and paper mills; Regeneration of gaseous SO2, e.g. arising from liquors containing sulfur compounds
    • D21C11/063—Treatment of gas streams comprising solid matter, e.g. the ashes resulting from the combustion of black liquor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Definitions

  • wood bark is first removed from logs, after which the remaining wood is cut into chips, and chemically processed (cooked) into fibers.
  • Lignin and some carbohydrate material are dissolved from wood chips during cooking in alkaline cooking liquor.
  • the lignin and carbohydrate material and the components of the cooking liquor form a waste liquor called black liquor.
  • the yield from wood to fiber is generally less than 50%, and typically 46 to 48% yields.
  • the chemicals are recovered from black liquor by firing the black liquor in a recovery boiler alone or together with other “waste” streams.
  • the firing process in the boiler is exothermic and the released energy is recovered as pressurized superheated steam.
  • the steam energy is recovered in a steam turbine to produce electric power and low-pressure steam for other pulp process needs.
  • biomass fuels which are alternative fuel sources.
  • alternative fuel sources reduce the need in a pulp mill for conventional fuels, such as coal and oil, and thereby reduce the amount of greenhouse gases produced by energy production using conventional fuels.
  • Biomass fuels may be used to provide steam at high live pressure and temperature which is an advantage in power generation efficiency.
  • Wood contains small amounts of potassium (K) and chlorine (Cl). These elements remain in the black liquor during cooking. In the recovery boiler, these elements are enriched into the fly ash and increase the corrosiveness of the flue gas especially in the superheater. The corrosiveness of Cl and K increase with temperature. The corrosiveness of Cl and K impose an upper temperature limit on the steam generated in the recovery boiler. This limit for the superheated steam is typically 400° to 490° C., depending on the content of chlorine and potassium. With special materials or with liquors having a very low Cl and K content, steam temperatures up to 520° C. have been used.
  • steam is heated in a recovery boiler to such a degree that high temperature corrosion does not take place.
  • the steam is heated to below 520° C., and optimally between 480 and 500° C.
  • the steam is superheated to 500° to 600° C. (and optimally to 520° to 560° C.) in a superheater(s) in a special combustion process in which clean fuel is burned so as to avoid high temperature corrosion.
  • the clean fuel is generated by gasification using a wood-based fuel.
  • the present invention is, in one example, a method of producing energy at a pulp mill comprising the following steps: a) combusting pulping process waste liquor (such as black liquor from kraft pulping) in the furnace of a recovery boiler to generate flue gases, b) recovering heat from the flue gases by producing either or both saturated and partially superheated steam in the recovery boiler, c) gasifying wood, bark or wood wastes in a gasifier to generate a combustible gas, d) burning at least part of the combustible gas in a superheating boiler, and e) superheating the saturated and partially superheated steam in the superheating boiler using heat energy from the burning of the combustible gas.
  • waste liquor such as black liquor from kraft pulping
  • the invention may gasify atmospherically solid wood-based fuels, such as wood, wood chips, bark chips, hogged wood, planer shavings, saw dust, wood-based forest residues, utilizing a gasifying method known to produce a combustible gas.
  • gases are, at least in part, burned in a separate superheating boiler and used to superheat the steam produced in a recovery boiler.
  • the temperature of the saturated or partially superheated steam produced by the superheater of the recovery boiler is limited to a level at which no boiler corrosion takes place or the corrosion rate is acceptably low.
  • the limit temperature depends on the corrosion conditions in the recovery boiler. In Scandinavian conditions, the temperature limit is in a range of typically 480° to 500° C. In practice, the corrosion temperature limit range is wide, e.g., 400° to 520° C., because of variations of the Cl and K levels in black liquor and the resulting fly ash and so called “carryover”, which is a char-containing type of fly ash.
  • the final superheating step occurs in a separate superheater, where the steam temperature reaches the final level, typically 450° to 600° C., preferably 500° to 560° C., and most preferably 530° to 560° C.
  • a temperature as high as 600° C. may be an acceptable limit.
  • the combustible gas generated from wood material contains alkaline compounds, such as sodium and potassium compounds, and chlorine-containing compounds, which may form alkaline chloride compounds, such as NaCl and KCl.
  • alkaline chloride compounds can cause corrosion at the high temperatures prevailing in the superheater.
  • the combustible gas from bark or wood gasification can be made non-corrosive by adding sulfur or sulfur-containing gas, such as non-condensable gases from cooking or foul condensate stripping, and by injecting sulfur-containing oil into the combustible gas flow from the gasifier.
  • Another technique for reducing the corrosiveness of the combustible gas is to burn the above-mentioned sulfur-containing fuels in gas burners of the superheating boiler. Cleaning for removing alkaline dust from the combustible gas prior to combustion in the superheater should also provide non-corrosive conditions at higher metal temperatures in the superheater. Some of the combustible gas can be used in a lime kiln to replace fossil fuels like oil and gas, resulting in an improvement in the greenhouse gas balance of the mill.
  • a system for producing energy at a pulp mill.
  • the system comprises: a recovery boiler having a furnace for combusting black liquor to produce flue gases; heat surfaces in the recovery boiler for recovering heat from the flue gases to generate steam; a superheating boiler connected to the heat surfaces of the recovery boiler for introducing the steam to the superheating boiler; a gasifier for gasifying solid wood-fuel, such as bark, to produce a combustible gas, and a conduit for supplying the combustible gas from the gasifier to the superheating boiler to burn the gas therein.
  • FIG. 1 is a schematic diagram of a unit for recovering energy from waste liquor in a pulp mill.
  • FIG. 1 illustrates a unit for recovering energy from waste liquor comprising a gasifier 10 , a waste liquor recovery boiler 14 , a heat recovery section 16 connected thereto, a separate superheating boiler 18 , a steam turbine 20 , a generator 22 , and a lime reburning kiln 24 .
  • Black liquor is sprayed via nozzles 26 into the recovery boiler 14 .
  • Combustion air is supplied to the recovery boiler through lines 28 at several levels of the boiler.
  • Molten, inorganic matter (a product of the combustion of the black liquor) flows through a char bed 30 accumulated on the bottom of the recovery boiler and to an outlet 32 that discharges into a dissolving tank (not shown).
  • wood material it is preferable to dry the wood material to be gasified. Gases generated from dry wood contain more combustible components, than do gases produced from damp wood. A higher portion of combustibles in gases increases the efficiency of combustion.
  • the wood material may be dried by the flue gases from the recovery boiler or a lime reburning kiln. For example, wood bark may be dried with flue gases from a lime reburning kiln. Such a drying process is described in U.S. Pat. No. 5,103,743, which is incorporated herein by reference.
  • Dried wood fuel such as bark
  • the gasification stage 10 which may be a circulating fluid bed (CFB) gasifier.
  • CFB circulating fluid bed
  • Other well-known gasifiers may also be applicable.
  • Combustible gas generated in the gasifier flow through a line 44 to the superheating boiler 18 .
  • a portion of the combustible gas may flow through line 46 to the lime reburning kiln 24 .
  • the corrosion of the heat surfaces 48 in the superheating boiler is reduced by additional combustion of sulphurous fuel, preferably non-condensable gases from the cooking plant and/or from the foul condensate stripping process.
  • the sulphurous fuel is supplied through line 54 and added to the combustible gas flow in line 44 or in burners 56 .
  • Sulfur reacts with alkali in the combustible gas to prevent or reduce the formation of alkaline chlorine compounds, which could, if allowed to form, cause corrosion in the superheating boiler, especially while at high temperatures.
  • Superheating surfaces 48 are disposed in the superheating boiler for superheating the steam coming from the recovery boiler through steam pipes 52 .
  • the superheated steam is led through a line 50 to the steam turbine plant.
  • a turbine 20 and generator 22 in the plant produce electric power.
  • Off-gases from the superheating boiler 18 are fed into the recovery boiler, preferably to the inlet of the superheater 40 , where they are mixed with the main flue gas stream coming from the boiler furnace.
  • Other possible locations for the off-gas inlets include the whole area from the lower part of the furnace to the inlet of the economizer 16 .
  • the off-gases can be fed through lines 58 and 28 to the furnace.
  • the flue gases from the superheating boiler 18 may be used to shape a flue gas flow pattern, from the furnace 15 of the recovery boiler over the “bull nose” 17 to improve gas distribution and heat transfer into the superheaters, or to generate conditions required for emission control, such as the optimum temperature window for selective non-catalytic reduction (SNCR) to reduce NO, emissions, or for particle size growth to reduce fine particle (size less than 2.5 micrometers) emissions.
  • SNCR selective non-catalytic reduction
  • Another possibility is to use these flue gases for shaping the flow pattern in the furnace 15 to improve mixing, e.g., introducing these gases via vertically located ports, as is described in European patent 668,983 (incorporated by reference herein), instead of air or mixed with air.
  • Combustion in the superheating boiler 18 may be performed also under sub-stoichiometric conditions. Reduced gases thus generated can be introduced into flue gases from the furnace 15 to reduce nitrogen oxide emissions in the flue gases coming from the furnace. It is known that certain fuels are more effective than others in reburning for reducing the content of nitrogen oxides in flue gases from the furnace of a recovery boiler. Reburning fuels can also be introduced into the flue gas flow(s) from the superheating boiler to improve gas mixing.

Landscapes

  • Paper (AREA)
  • Processing Of Solid Wastes (AREA)
  • Incineration Of Waste (AREA)
US10/423,052 2002-05-13 2003-04-25 Method of producing energy at a pulp mill Abandoned US20040011484A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US10/423,052 US20040011484A1 (en) 2002-05-13 2003-04-25 Method of producing energy at a pulp mill

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US37940602P 2002-05-13 2002-05-13
US10/423,052 US20040011484A1 (en) 2002-05-13 2003-04-25 Method of producing energy at a pulp mill

Publications (1)

Publication Number Publication Date
US20040011484A1 true US20040011484A1 (en) 2004-01-22

Family

ID=29420526

Family Applications (1)

Application Number Title Priority Date Filing Date
US10/423,052 Abandoned US20040011484A1 (en) 2002-05-13 2003-04-25 Method of producing energy at a pulp mill

Country Status (10)

Country Link
US (1) US20040011484A1 (pt)
EP (1) EP1504154B2 (pt)
JP (1) JP2005525526A (pt)
CN (1) CN1309901C (pt)
AU (1) AU2003227784A1 (pt)
BR (1) BRPI0301313B1 (pt)
CA (1) CA2484718C (pt)
ES (1) ES2409332T5 (pt)
PT (1) PT1504154E (pt)
WO (1) WO2003095738A1 (pt)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050252624A1 (en) * 2002-07-22 2005-11-17 Oy Metsa-Botnia Ab Process and apparatus for producing thermal and electric energy
US20060236696A1 (en) * 2005-04-22 2006-10-26 Andritz Oy Apparatus and method for producing energy at a pulp mill
US10844301B2 (en) * 2015-11-04 2020-11-24 Haffner Energy Method for producing a synthesis gas

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100422434C (zh) 2002-06-07 2008-10-01 安德里兹公司 造纸厂用来产生能量的***
JP4284251B2 (ja) * 2004-08-25 2009-06-24 新日鉄エンジニアリング株式会社 廃棄物発電ボイラの腐食抑制方法
TR200703816A2 (tr) * 2007-06-04 2009-02-23 Hayat K�Mya Sanay� Anon�M ��Rket� Temizlik kağıdı üretiminde bir kojenerasyon uygulaması
FR3012578B1 (fr) 2013-10-24 2015-12-11 Suez Environnement Procede et installation de valorisation energetique de dechets
CN105180150A (zh) * 2015-07-08 2015-12-23 云南汉光纸业有限公司 造纸生产线锅炉过热蒸汽调配利用***
FI128267B (fi) 2017-05-10 2020-02-14 Valmet Technologies Oy Menetelmä ja järjestelmä höyryä höyryturbiinille tuottavan kattilan käsittävän voimalaitoksen kuormitusalueen laajentamiseksi
FI128373B (en) * 2017-06-20 2020-04-15 Valmet Automation Oy Method for controlling a recovery boiler

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2606103A (en) * 1947-06-13 1952-08-05 Comb Eng Superheater Inc Chemical recovery furnace with high-temperature superheater
US4498909A (en) * 1982-11-02 1985-02-12 Dm International, Inc. Process for the gasification of fuels
US4699632A (en) * 1983-08-02 1987-10-13 Institute Of Gas Technology Process for gasification of cellulosic materials
US5509997A (en) * 1991-11-26 1996-04-23 A. Ahlstrom Corporation Method of recovering energy from waste liquors from pulp processes

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2606103A (en) * 1947-06-13 1952-08-05 Comb Eng Superheater Inc Chemical recovery furnace with high-temperature superheater
US4498909A (en) * 1982-11-02 1985-02-12 Dm International, Inc. Process for the gasification of fuels
US4699632A (en) * 1983-08-02 1987-10-13 Institute Of Gas Technology Process for gasification of cellulosic materials
US5509997A (en) * 1991-11-26 1996-04-23 A. Ahlstrom Corporation Method of recovering energy from waste liquors from pulp processes

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050252624A1 (en) * 2002-07-22 2005-11-17 Oy Metsa-Botnia Ab Process and apparatus for producing thermal and electric energy
US20060236696A1 (en) * 2005-04-22 2006-10-26 Andritz Oy Apparatus and method for producing energy at a pulp mill
WO2006111608A1 (en) * 2005-04-22 2006-10-26 Andritz Oy Apparatus and method for producing energy at a pulp mill
US7640750B2 (en) * 2005-04-22 2010-01-05 Andritz Oy Apparatus and method for producing energy at a pulp mill
US10844301B2 (en) * 2015-11-04 2020-11-24 Haffner Energy Method for producing a synthesis gas

Also Published As

Publication number Publication date
EP1504154B1 (en) 2013-03-13
ES2409332T3 (es) 2013-06-26
BRPI0301313B1 (pt) 2015-06-09
WO2003095738A1 (en) 2003-11-20
CA2484718A1 (en) 2003-11-20
BR0301313A (pt) 2004-08-17
CN1309901C (zh) 2007-04-11
CN1653228A (zh) 2005-08-10
ES2409332T5 (es) 2017-06-13
JP2005525526A (ja) 2005-08-25
EP1504154A1 (en) 2005-02-09
CA2484718C (en) 2009-04-21
EP1504154B2 (en) 2016-11-23
AU2003227784A1 (en) 2003-11-11
PT1504154E (pt) 2013-06-03

Similar Documents

Publication Publication Date Title
EP1924739B1 (en) Apparatus and method for producing energy at a pulp mill
CA2488062C (en) System for producing energy at a pulp mill
US5685138A (en) Integrated drying of feedstock feed to IGCC plant
US5507141A (en) Process for recovering energy from a combustible gas
US4866928A (en) Gas turbine power plant fired by a water-bearing fuel and method for utilizing the heat value of said fuel
US20090077971A1 (en) Method and deivce for the production of superheated steam
CA2484718C (en) Method of producing energy at a pulp mill
US5509997A (en) Method of recovering energy from waste liquors from pulp processes
US4872950A (en) Process for recovering energy and chemicals from spent liquor in pulp preparation
CA2196503C (en) Method and apparatus for treating pulping process waste liquors
CA2492824C (en) Process and apparatus for producing thermal and electric energy
CN101680175A (zh) 用于纸浆厂的回收方法
Nikkanen Liquor heat treatment and high-dry-solids firing
FI122536B (fi) Laitteisto energian tuottamiseksi sellutehtaalla

Legal Events

Date Code Title Description
AS Assignment

Owner name: ANDRITZ OY, FINLAND

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SAVIHARJU, KARI;SIMONEN, JORMA;ARPALAHTI, OLLI;AND OTHERS;REEL/FRAME:014459/0096;SIGNING DATES FROM 20030812 TO 20030814

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO PAY ISSUE FEE