US3698860A - Method for converting sodium sulfide to sodium sulfite - Google Patents

Method for converting sodium sulfide to sodium sulfite Download PDF

Info

Publication number
US3698860A
US3698860A US871930A US3698860DA US3698860A US 3698860 A US3698860 A US 3698860A US 871930 A US871930 A US 871930A US 3698860D A US3698860D A US 3698860DA US 3698860 A US3698860 A US 3698860A
Authority
US
United States
Prior art keywords
sodium
smelt
particles
pulp
sulfite
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.)
Expired - Lifetime
Application number
US871930A
Other languages
English (en)
Inventor
Kaoru Shiba
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.)
Individual
Original Assignee
Individual
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
Application filed by Individual filed Critical Individual
Application granted granted Critical
Publication of US3698860A publication Critical patent/US3698860A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
    • C01D5/14—Preparation of sulfites
    • 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
    • D21C11/12—Combustion of pulp liquors
    • D21C11/122—Treatment, e.g. dissolution, of the smelt
    • 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S423/00—Chemistry of inorganic compounds
    • Y10S423/03—Papermaking liquor

Definitions

  • the invention concerns the conversion of sodium sulfide contained in the ash content of burnt black liquor side-produced of pulp digestion to sodium sulfite by oxidation, and recovery of the converted product for reuse as pulp digesting chemical, the conversion and recovery being performed throughout as a wet process.
  • the invention is applicable to recovery of the chemical employed in semichemical pulp process using neutral sodium sulfite and sulfite pulp process using acidic sodium sulphite among the various preparation methods of pulp.
  • the ash content of the black liquor side-produced of pulp digesting is normally composed of sodium sulfide (Na s), sodium thiosulfate (Na S O sodium sulfite Na,s0,), Sodium sulfate (Na SO sodium carbonate Na,co, and a minor amount of insoluble matter, Na CO content being approximately 60% by weight, and that of Na S being more than 20% by weight.
  • Na s sodium sulfide
  • Na S O sodium sulfite Na,s0 sodium sulfate
  • Na SO sodium carbonate Na,co sodium carbonate
  • Na S sodium sulfide
  • Na SO sodium sulfite
  • tosodium sulfate Na SO if oxidized under severer conditions
  • reaction (1) takes place at temperatures above 100 C. and the reaction (2), at above 300 C., the reactions being accelerated by the use of air containing steam, the reaction (1) is exothermic, and causes abrupt temperature rise in the reaction system to induce the reaction (2), forming sodium sulfate (Na SO which is useless as a pulp digesting chemical. This is quite unavoidable since 1 kg. of sodium sulfide (Na s) generates the heat of as much as 2,200 kilocalories through the reaction (1).
  • Na S+H O NaHS+NaOH (3)
  • 2NaHS+2O Na S O +H O (4)
  • This invention successfully solved those problems inherent in the direct oxidation which is one of the recovery means of pulp-digesting chemicals from smelt obtained by concentrating and burning the semi-chemical pulp and sulfite pulp originated black liquor, in which the above reactions (2), (3), and (4) are effectively inhibited, whereby enabling recovery of high purity pulpdigesting chemicals at high yields throughout by wet process, concurrently effecting prevention of public nuisance.
  • sodium sulfide (M1 8) is very efficiently converted to sodium sulfite (Na SO while preventing formation of sodium thiosulfate.
  • M1 8 sodium sulfide
  • Na SO sodium sulfite
  • the smelt flowing from the furnace bottom upon burning of black liquor from pulp digesters is dropped into saturated solution of the smelt to be instantaneously cooled and solidified. It is a preferred practice to subject the flowing smelt to a steam or water jet on the quenching solution surface so as to convert it into fine particles immediately before dropping into the solution, similarly to the known practice in kraft pulp process. This has the same effect as of grinding.
  • the subject method however is different from kraft pulp process in that the solution in the smelt-receiving tank has the composition quite close to the saturated solution of smelt. Therefore, the solid particles of the quenched smelt in the receiving tank are not dissolved, but precipitate or float in the receiving tank. The particles are separated from the solution by filtration or sedimentation, and if they still have excessively large particle sizes, pulverized with a wet-type grinder. The ash particles, i.e., solidified smelt, are formed into a slurry as mixed with water at suitable ratio. The optimum slurry concentration diifers depending on sodium sulfide (Na s) content of the smelt, but generally that of not lower than 50% is preferred.
  • Na s sodium sulfide
  • the slurry In order to improve the flowability of the slurry, it may be heated at suitable places with steam or other suitable means, so as to maintain a temperature not lower than 80 C. Then the slurry is sent to the direct oxidation Zone.
  • the construction of direct oxidation zone is variable, the matter of prime importance being that the zone must be capable of thoroughly mixingfinely divided hydrous particles to allow their sufiicient contact with air. That is, a converter capable of such perfect mixing of the wet particles is packed with finely divided particles containing no sodium sulfide (Na s) in advance, and maintained at the temperature within 100-300 C., and preferably of approximately 110 C. to 120 C., and into which aforesaid wet ash particles are fed at a slow rate.
  • Na s sodium sulfide
  • the temperature within the converter can be optionally controlled by regulating the quantities of sodium sulfide (Na s) content and water content of the slurry being fed.
  • Na s sodium sulfide
  • the optimum ratio between the ash and water for suitable temperature control in the converter is, if sodium sulfide (Na S) content of the dry ash is 25%, 1 kg. of ash per 1 kg. of water. In practice, however, it is the easiest way of temperature control to supply more than 1 kg. of ash per 1 kg. of water and if the temperature in the converter rose above the predetermined level, to feed water into the converter, since sodium sulfide (Na s) content of the ash varies incessantly.
  • direct oxidation of smelt is performed by the steps of collecting the smelt by dry system, solidifying the same by cooling, followed by grinding and contacting the comminuted solid with mixture of air and steam.
  • the dry solidifier often causes troubles, and during the grinding noxious dust scatters about to make the operation hazardous.
  • the conventional process is again subject to the serious defect that due to the difliculties for controlling direct oxidation temperature, the product comes to contain objectionably large amounts of impurities such as unreacted Na s (residual sodium sulfide), sodium thiosulfate (Na S O and sodium sulfate (Nazsoa), etc.
  • impurities such as unreacted Na s (residual sodium sulfide), sodium thiosulfate (Na S O and sodium sulfate (Nazsoa), etc.
  • the dry solidifyer which is apt to cause troubles is dispensed with, and because wet system is employed, scattering about of dust never takes place. Obviously, there is neither a danger of any dust explosion.
  • the temperature can be easily and accurately controlled, the product contains little impurities. There is no need of mixing steam with air as the oxidizing agent, as an extra step.
  • NaS sodium thiosulfate
  • the products value as a digesting chemical may be somewhat reduced for the pulp-making where the presence of sodium thtiosulfate is strictly prohibited. Therefore, still another unique step is incorporated in the invention to overcome this objection. That is, a minor amount of sodium hydroxide (NaOH) is added to the slurry formed by mixing the ash particles separated from the receiving tank with water, before the slurry is reacted in the converter. Normally desirable amount of NaOH ranges from 2 to 20% by weight of dry, solid particles.
  • the ash particles as separated from the receiving tank naturally contain water, and consequently are undergoing the aforesaid reaction 3), whereas, since the ash particles concurrently contain considerable amount of sodium carbonate (Na CO the amount of sodium hydrosulfide (NaHS) formed of the reaction (3) is at most several percents of that of sodium sulfide (Na s), as can be understood from the concept of chemical equilibrium.
  • NaOH sodium hydroxide
  • NaHS sodium hydrosulfide
  • the drawing shows a process diagram of a pilot plant in which 10 kg./hr. of smelt flows out from the furnace bottom.
  • the smelt flowing from a black liquor incinerator (not shown) flew down through the spout 1 into saturated solution of the smelt in a receiving tank 2.
  • the smelt was formed into fine particles by the steam jet 3.
  • the smelt solidified as dropped into the solution was carried to the vibrating screen 5 by a slurry pump 4, where the particles were separated from the solution and flew down into the dish grinder 6, to be further comminuted into finer particles of less than mesh in size.
  • the filtrate was returned to the receiving tank 2.
  • an aqueous liquid 7 for temperature control was added, which also served as a transporting medium to assist smooth flowing down of the particles into the disk grinder 6 and discharging of particles from the same grinder.
  • This transporting medium was supplied from the solution in the receiving tank 2, and water was separately supplied to the receiving tank 2.
  • the converter 8 a kneader of 25 liters in capacity with two rotating blades was used in this particular example.
  • the compositions of the starting smelt and the product were as given below:
  • NaOH sodium hydroxide
  • the product of the invention has higher sodium carbonate (Na CO and sodium hydroxide (NaOH) contents and lower sodium sulfite (Na SO content, compared with normally used digesting liquor in pulp industry.
  • Na CO and NaOH sodium carbonate
  • Na SO sodium sulfite
  • the apparatus shown in the above embodiment is no more than one suitable example, which may very well be replaced by other equally effective apparatuses.
  • the converter fluidized bed, rotary kiln, or cement mixer can be used with equivalent results.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Paper (AREA)
  • Manufacture And Refinement Of Metals (AREA)
US871930A 1968-10-30 1969-10-28 Method for converting sodium sulfide to sodium sulfite Expired - Lifetime US3698860A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP7878868 1968-10-30
JP5840769 1969-07-25

Publications (1)

Publication Number Publication Date
US3698860A true US3698860A (en) 1972-10-17

Family

ID=26399463

Family Applications (1)

Application Number Title Priority Date Filing Date
US871930A Expired - Lifetime US3698860A (en) 1968-10-30 1969-10-28 Method for converting sodium sulfide to sodium sulfite

Country Status (4)

Country Link
US (1) US3698860A (https=)
DE (1) DE2200641A1 (https=)
FR (1) FR2168175A1 (https=)
GB (1) GB1328920A (https=)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4100253A (en) * 1976-06-25 1978-07-11 Union Carbide Corporation Recovery of sodium and antimony values from spent ethylene glycol residues
US4141785A (en) * 1976-03-17 1979-02-27 Ebara Manufacturing Co., Ltd. Process for recovery of chemicals from pulping waste liquor
CN102877350A (zh) * 2012-09-29 2013-01-16 广西大学 一种木素提取联合碱回收的黑液处理方法
US9114988B2 (en) 2011-04-15 2015-08-25 Aditya Birla Science and Technology Company Private Limited Process for separation and purification of sodium sulfide
US9410042B2 (en) 2012-03-30 2016-08-09 Aditya Birla Science And Technology Company Ltd. Process for obtaining carbon black powder with reduced sulfur content
US9873797B2 (en) 2011-10-24 2018-01-23 Aditya Birla Nuvo Limited Process for the production of carbon black

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1980002574A1 (en) * 1979-05-18 1980-11-27 Australian Paper Manufacturers Pulping liquor reutilization
CN100463855C (zh) * 2006-10-31 2009-02-25 赵志军 利用硫化碱还原废水生产亚硫酸钠和硫化钠的方法

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4141785A (en) * 1976-03-17 1979-02-27 Ebara Manufacturing Co., Ltd. Process for recovery of chemicals from pulping waste liquor
US4212702A (en) * 1976-03-17 1980-07-15 Ebara Manufacturing Company, Limited Process for recovery of chemicals from pulping waste liquor
US4100253A (en) * 1976-06-25 1978-07-11 Union Carbide Corporation Recovery of sodium and antimony values from spent ethylene glycol residues
US9114988B2 (en) 2011-04-15 2015-08-25 Aditya Birla Science and Technology Company Private Limited Process for separation and purification of sodium sulfide
US9873797B2 (en) 2011-10-24 2018-01-23 Aditya Birla Nuvo Limited Process for the production of carbon black
US9410042B2 (en) 2012-03-30 2016-08-09 Aditya Birla Science And Technology Company Ltd. Process for obtaining carbon black powder with reduced sulfur content
CN102877350A (zh) * 2012-09-29 2013-01-16 广西大学 一种木素提取联合碱回收的黑液处理方法
CN102877350B (zh) * 2012-09-29 2014-10-15 广西大学 一种木素提取联合碱回收的黑液处理方法

Also Published As

Publication number Publication date
GB1328920A (en) 1973-09-05
DE2200641A1 (de) 1973-07-19
FR2168175A1 (https=) 1973-08-31

Similar Documents

Publication Publication Date Title
US4636379A (en) Process for producing calcium hydroxide
US3309262A (en) Fluidized bed oxidation of waste liquors resulting from the digestion of cellulosic materials for paper making
AU746088B2 (en) Process and apparatus for preparing precipitated calcium carbonate
US4676953A (en) Continous production of sodium silicate solutions
US3698860A (en) Method for converting sodium sulfide to sodium sulfite
US3268388A (en) Manufacture of calcium carbonate
US4504356A (en) Continuous process of removing silica from spent pulping liquors
US3840638A (en) Production of gypsum from combustion exhaust gas
US3314748A (en) Production of dense soda ash
US4154643A (en) Recovery process and apparatus for alkali metal-containing spent liquor
US3268387A (en) Manufacture of calcium carbonate
US6555077B1 (en) Organic impurity removal process for bayer liquors
US1560900A (en) Process of treating wate sodium monosulphite liquors
US4212702A (en) Process for recovery of chemicals from pulping waste liquor
NO172137B (no) Fremgangsmaate for aa utvinne natriumhydroxyd fra en alkalisk avlut fra cellulosefremstilling
US2717825A (en) Apparatus for conversion of sodium sulphide to sodium sulphite
US3787283A (en) Treatment of waste liquor from pulp production
US2640758A (en) Method of oxidizing sodium sulfide to sodium sulfite in successive stages
US3549484A (en) Method and apparatus for the recovery of sulfite waste liquors
US4035228A (en) Recovery process and apparatus for alkali metal-containing waste liquor
US2642336A (en) Conversion of sodium sulfide to sodium sulfite
US5545385A (en) Process for recovering alkali metal hydroxide from organic liquors
CA1104765A (en) Process for recovery of chemicals from pulping waste liquor
US3480386A (en) Process for acid digestion of titaniferous materials
US3554858A (en) Process for regeneration of white liquor with hydrogen sulfide recycle