US3870784A - Sodium bicarbonate production - Google Patents

Sodium bicarbonate production Download PDF

Info

Publication number
US3870784A
US3870784A US305397A US30539772A US3870784A US 3870784 A US3870784 A US 3870784A US 305397 A US305397 A US 305397A US 30539772 A US30539772 A US 30539772A US 3870784 A US3870784 A US 3870784A
Authority
US
United States
Prior art keywords
sodium bicarbonate
zone
crystals
stream
mixture
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
US305397A
Other languages
English (en)
Inventor
Walter C Saeman
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.)
Olin Corp
Original Assignee
Olin Corp
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 Olin Corp filed Critical Olin Corp
Priority to US305397A priority Critical patent/US3870784A/en
Priority to CA158,713A priority patent/CA966975A/en
Priority to GB5748572A priority patent/GB1402158A/en
Priority to FR7246761A priority patent/FR2169886B1/fr
Priority to JP48004344A priority patent/JPS4879199A/ja
Priority to DE2264087A priority patent/DE2264087A1/de
Application granted granted Critical
Publication of US3870784A publication Critical patent/US3870784A/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
    • C01D7/00—Carbonates of sodium, potassium or alkali metals in general
    • C01D7/10—Preparation of bicarbonates from carbonates

Definitions

  • the separated crystals are suitably 1 3 7/1932 v a 423/189 washed, dried and sized to obtain the sodium bicar- 2,142,9l7 1/1939 Reich 423/232 bonate product. 2.183.324 12/1939 Reich... 423/232 2,256,962 9/1941 Reich 423/232 15 Claims, 4 Drawing Flgures SODA 49/ i ,Z? f2 l4 22 j ⁇ l f ⁇ 11 a 2? g 14 zffld s E 5 3 A M 5; 44-15 7a 5a 1/ H0 40 1 H l 4 2 5 l 4 1 4 43 5!
  • This invention relates to a process for producing sodium bicarbonate from soda ash or caustic by carbonation and particularly to a process for so producing sodium bicarbonate meeting wide ranges of size specifications under minimum scaling and heat load conditions.
  • the principal objects of the present invention are (1 to provide a carbonation process for producing granular sodium carbonate in which crystal size can be controlled and which can be utilized, for example, to economically produce 'a crystal size up to ZO-mesh (2) to provide such a process which circumvents the scaling problems discussed above and the economic consequences of the prior art solutions.
  • the present invention minimizes costs of starting materials by efficient use of low cost sources of CO by utilizing any common form of soda ash including trona ash or light soda ash from the ammonia-soda process, or by utilizing caustic as a raw material in lieu of or in addition to soda ash. It further minimizes costs of the process by minimizing the heat load on the system and by promoting more efficient use of machinery utilized in the process.
  • a second aqueous stream is removed from the upper portion of the aqueous mixture in the classification zone; said second stream is heated and fresh soda ash is dissolved therein and the resulting fortified solution is sprayed into the carbonating zone.
  • This modification is advantageous when said second aqueous stream contains suspended fine crystals of sodium bicarbonate.
  • the second aqueous stream is heated in a regenerative heat exchanger; soda ash is dissolved in the heated solution and the enriched solution is cooled by regenerative heat exchange with the entering stream and the fortified solution is returned to the carbonation zone.
  • This modification is advantageous when said second aqueous stream contains suspended fine crystals of sodium bicarbonate.
  • fine, dry soda ash is fed directly into the sodium bicarbonate slurry in the crystallization zone where the added ash dissolves rapidly and does not substantially affect the purity of the bicarbonate crystals present in the crystallization zone.
  • aqueous caustic is used in lieu of soda ash in the process and the aboveidentified modifications.
  • aqueous caustic is subjected to two stage carbonation utilizing recycled mother liquor and carbon dioxide vapor exhausted from a'bicarbonate crystallizer-absorber.
  • FIG. 1 is a flow chart showing the preferred embodiment of the invention.
  • FIG. 2 is a flow chart showing the first modification of the preferred embodiment utilizing a regenetative heat exchanger.
  • FIG. 3 is a flow chart showing the second modification of the preferred embodiment wherein dry soda ash is introduced directly into the crystallization zone without dissolution or filtration of feed solution.
  • FIG. 4 is a flow chart showing the further modification utilizing two stage carbonation of caustic.
  • FIG. 1 fortified but unsaturated aqueous solution of soda ash is introduced via line 35 through sprays 12 into an upper region of in the gas filled carbonation zone 13 of the classifying crystallizershown generally at 14.
  • Sprays 12 are arranged andpressure is controlled to promote impinging of the droplets on the roof and walls of crystallizer 14 to provide a flow of unsaturated feed solution over the roof and down the walls of carbonation zone 13 and into crystallization zone 11 in order to minimize scale formation.
  • Crystallization zone 11 and classification zone 15 contain a mixture of sodium bicarbonate crystals in an aqueous solution of sodium carbonate saturated and in equilibrium with sodium bicarbonate.
  • Crystallization zone 11 and classification zone 15 contain a mixture of sodium bicarbonate crystals in an aqueous solution of sodium carbonate saturated and in equilibrium with sodium bicarbonate.
  • crystallization zone is generally defined at the top by the liquid level below carbonation zone 13, and at the bottom by the termination of conical baffle 77. Appended to the lower edge of the baffle is cylindrical screen 78 which blocks passage of scale fragments too large to pass through orifices in nozzles 24. Conical baffle 77 and screen 78 thus physically separate crystallization zone 11 from classification zone 15.
  • the upper portion of liquor in classification zone 15 comprises crystal free mother liquor and/or mother liquor containing suspended relatively fine crystals of sodium bicarbonate; the lower portion thereof contains relatively coarser crystals of sodium bicarbonate.
  • a stream containing relatively larger volumes are drawn from crystallization zone 11, through classification zone 15, through line 21, cooled as desired in cooler 22, returned via line 23 to crystallizer l4 and dispersed through nozzles 24 in the lower region of carbonation zone 13.
  • Nozzles 24 are positioned to direct the spray upward and inwardly from the perimeter of the tower to maximize mid-air collision of droplets moving in opposite directions and to minimize direct wall impingement of the droplets.
  • Carbon dioxide is provided in carbonation zone 13 in the form of washed stack gas via line 16. Exit gas is vented via line 17. Additional cooling is suitably provided if desired by directing a portion of vent gas via line 18 through cooler 19 and recycling it via line 20 with the incoming stack gas.
  • An aqueous stream containing suspended fines of sodium bicarbonate is removed from classification zone 15 of crystallizer l4, heated in transit as desired in steam heater 26 and returned to dissolver 29.
  • Fresh soda ash is introduced to dissolver 29 via line 30.
  • Line 31 is provided for the introduction of fine, solid soda ash as desired directly into the liquor in crystallizer l4.
  • Fortified feed solution leaves dissolver 29 via line 32, passes through filter 33 and is transferred via line 35 to sprays 12.
  • a slurry of coarse crystals is removed from the lower portion of classification zone 15 of crystallizer 14 via line to centrifuge 41.
  • Mother liquor is recycled via line 42 preferably to the classification zone.
  • Purge line is provided at 43.
  • a slurry of fines is removed from classification zone 15 via line 44 to centrifuge 41.
  • the fines are returned via line 25 to dissolver 29.
  • the centrifuged product is washed with water from line 45 and then transferred via line 46 to rotary drier 47 heated by burning fuel and air in burner 48 and transferring the burner gas via line 49 to drier 47.
  • Effluent gas containing fines and CO pass via line 50 to fines collector 51 from which fine product is removed via line 52.
  • Effluent gas from fines collector 51 is dehumidified by cool water introduced by line 53 into dehumidifier 54 and the dehumidified gas is vented via line 55 or recycled to drier 47 via line 56.
  • Water from dehumidifier 54 is returned via line 57 and heater 26 to dissolver 29. Crystal sodium bicarbonate product is removed from drier 47 via line 58.
  • FIG. 1 Fortified but unsaturated aqueous solution of soda ash is introduced via line 35 through sprays 12 in the gas filled carbonating zone 13 of crystallizer 14. Recirculation of the suspension is as in FIG. 1. Carbon dioxide is provided and exit gas is vented and/or rccirculated with cooling as in FIG. 1.
  • Aqueous stream 62 is removed from classification zone 15 and introduced into regenerative heat exchanger 66.
  • the liquor heated by vapor condensation, leaves the heat exchanger 66 via line and is transferred to dissolver 29, additional optional heating as desired is provided by heater 26.
  • Fortified liquor leaves dissolver 29 via line 32, passes through filter 33 and leaves via line 64 to the first stage of the lower section of regenerative heat exchanger 66.
  • a portion of the uncooled, fortified liquor from line 64, heated by dissolution of soda ash therein, is split off for washing the roof of the absorber via line 35.
  • the effluent liquor, cooled by evaporation in heat exchanger 66 is returned via line 65 to crystal suspension zone 11 of crystallizer l4.
  • Vapor transfer lines of heat exchanger 66 are shown at 67, 68 and 69. Liquid transfer lines of heat exchanger 66 are shown at 71, 72, 73, and 74. A similar heat exchanger is described in Journal of Metals, July I966, pages 811-818. Product recovery and drying is as in FIG. 1.
  • FIG. 3 A simpler form of the invention is illustrated in FIG. 3. Fine soda ash is fed directly into the saturated crystallizer liquor via line 31. An aqueous stream 25 containing suspended fines of sodium bicarbonate is removed from classification section 15 of crystallizer 14, heated in heater 26 and transferred via line 35 to sprays 12. Recirculation of the crystallizer liquor and recovery of product is as described in FIG. 1. This modification of the invention eliminates the cost of dissolving the feed and filtering the feed solution. The cost of the steam for dissolving the feed is also eliminated. The product does not meet food grade specifications but capital investment and utility costs are reduced to a minimum.
  • ash must be dissolved and filtered before this stream is admitted to the crystallizer.
  • the liquor introduced into the feed dissolving circuit from the crystallizer must be heated to establish sufficient dilution to serve as a dissolving medium for the ash. Steam to supply this heat is a major cost item in the production of the crystal bicarbonate.
  • the heat of solution of soda ash in the liquor is moderately exothermic. Therefore, regenerative heating and cooling by efficient countercurrent contacting of the liquor entering the ash dissolver with the liquor leaving the ash dissolver is utilized. Scaling may occur in the regenerative heater due to the occurrence of supersaturation as the enriched mother liquor is cooled. Heat transfer by vapor exchange is not impaired by scaling. Scale which forms in a vapor exchanger can also be quickly dissolved by intermittent steaming. Absorber wall scale formation is minimized by distribution of hot, enriched, but slightly dilute mother liquor from the feed dissolving circuit directly onto the upper walls of the absorber.
  • caustic may be substituted for soda ash in the modifications shown by FIGS. l-3 without substantial modification of the systems shown in the flow charts.
  • caustic means caustic soda or aqueous sodium hydroxide.
  • caustic rather than soda ash would be introduced into the crystallizer via line 31.
  • Mixing of the caustic with sodium bicarbonate containing liquor converts the caustic to sodium carbonate according to the following reactions:
  • FIG. 4 A further modification of the system utilizing caustic in lieu of soda ash is illustrated in FIG. 4.
  • Aqueous caustic is introduced via line 75 into a first stage carbonation unit 76 in which it is carbonated to form a finely divided monohydrated crystalline Na CO precipitate.
  • the first stage carbonation is carried out at elevated temperature increasing the efficiency of CO absorbtion over that which can be obtained by preliminary carbonation in the crystallizer-absorber.
  • Carbonation may be effected in this first-stage unit either by passing an aqueous caustic solution through an atmospher of CO or by passing CO through the aqueous solution, both such methods being well known in the art.
  • the suspension in the first stage carbonator should contain a ratio of 25 pounds of monohydrated Na CQ to 60 pounds saturated ash solution. Due to the lack of water entering the system in the aqueous caustic (about 50 percent H 0) and the high evaporation resulting from high-operating temperatures dilute mother liquor is recycled via line 43a to maintain the ratio.
  • the first stage absorber at a temperature of up to 90C, as much as above the temperature at which the second stage absorber-crystallizer operates, increasing carbon dioxide absorbtion about 9 fold.
  • gas vented from the second stage absorber crystallizer and to introduce this into the absorber 76 as a source of CO, for the first stage absorber through line 17a.
  • the absorber 76 thus acts as a scrubber for gasses which would normally be vented through a special scrubber from the bicarbonate absorber-crystallizer. If additional carbon dioxide is required, it may be supplied via line 16a.
  • the crystal suspension in the crystallizer is re-circulated and sprayed into an atmosphere containing at least 4 percent CO in an open absorption column immediately above an exposed crystal suspension.
  • Supersaturation is induced by the absorption of CO in the carbonatecontaining mother liquor.
  • the sprayed liquor then drops into the contiguous crystallization zone below.
  • Fine crystals are segregated and removed from the suspension in the connecting classification zone as required to balance the amount of seed in the suspension withthe crystal production rate.
  • Nazcog CO H20 Addition to the mother liquor of Na CO either in so lution or in solid form compensates for carbonate depletion by bicarbonate formation and sustains the Na CO concentration of the mother liquor in the range indicated above. Na cO in solid form dissolves in the mother liquor and induces crystallization of NaHCO by salting it out.
  • the soda ash feed solution is filtered to avoid accidental entry of insoluble foreign matter into the suspension. Heat requirements are minimized if the ash is dissolved in heated mother liquor. Further minimization of heat requirement results form regenerative heating and cooling in a countercurrent exchanger of solution entering and leaving the feed ash dissolver. Crystal growth is induced by cooling the enriched feed solution in contact with the suspension.
  • Prior art methods for the absorption of gases in liquids are by contact in packed towers, by dispersing liquid in the gas as a spray or cascade, and by dispersing gas bubbles in the liquid.
  • scaling due to separation of solids from saturated solutions is a serious problem detrimental to productivity and expensive to combat.
  • scaling is minimized or avoided by dispersing the warm aqueous mixture as a spray in an open absorber tower devoid of fixed surfaces in close proximity to one another.
  • Contact time of the spray droplets with the CO in the atmosphere of the tower is limited to avoid excessive supersaturation and the resulting undesirable spontaneous nucleation.
  • Droplet residence time in the CO atmosphere is suitably from about 1 to seconds, preferably about 2 seconds.
  • Desupersaturation time in the crystallization zone is suitably from 1 to 10 minutes, preferably about 3 minutes.
  • the longer growth time afforded by the process of this invention in relation to the droplet residence time for CO absorption results in a reduced rate of crystal growth, improved crystal structure and strength. Degradation in centrifuging and drying is thereby substantially avoided.
  • scaling of the walls is minimized by directing the sprays upwardly and inwardly from opposed wall positions. Direct contact of the drops with the walls is thereby reduced by mid-air collision between drops moving in opposite directions. Descaling of the absorber walls is also effected by flowing warm unsaturated feed solution over all internal wall surfaces.
  • control of the residence time of the droplets in the CO absorption space prevents excessive supersaturation and also contributes to the prevention of scaling in the interior walls. Minor scaling, if it commences locally, is tolerable on the smooth interior walls of the absorber where it is not in close proximity to other surfaces. The absorber is thus insensitive to scale accumulations.
  • the method of the present invention is a vast improvement over the conventional bicarbonate towers of the prior art, with inaccessible and closely spaced interior surfaces which are extremely sensitive to scale formation and are difficult to descale.
  • crystal size is controlled by any suitable means.
  • the methods fully disclosed, for example, in US. Pat. Nos. 2,856,270 and 2,883,273 are suitable. Negligibly small crystals are segregated and removed from the suspension in the classification zone as required to maintain a suspension seed rate in balance with the crystal production rate. Conventional bicarbonate towers are devoid of this feature and cannot produce premium grades of coarse granular sodium bicarbonate.
  • essentially clear mother liquor, free of crystals, except for a negligible quantity of excess fines which may be dispersed therein, is withdrawn from the classification zone to the dissolving circuit Where dry sodium carbonate is dissolved therein by heating.
  • the heated, enriched solution is filtered and returned to the absorption zone to maintain the concentration of Na CO and NaHCO at preferred operating concentrations.
  • Cooling of the heated feed solution either before or after return to the crystallization zone serves to provide supersaturation to promote crystal growth in addition to the supersaturation provided by absorption of CO Heating of the mother liquor de-saturates the liquor and permits it to be utilized to dissolve additional sodium carbonate.
  • Heating of the mother liquor also destroys excess crystal nuclei removed from the elutriation zone.
  • a particularly advantageous method of heating and cooling the liquor in the feed dissolving circuit is by passing the solution countercurrently to itself through a regenerative heat exchanger.
  • the heat of solution of dry soda ash is exothermic and the solution leaving the feed dissolving tank is hotter than the solution entering.
  • This differential in temperature is utilized in a regenerative heat exchanger to cool the heated, enriched filtered solution returning to the crystallizer by countercurrent contact with the cooler mother liquor flowing from the crystallizer to the dissolving tank.
  • the regenerative heat exchanger obviates the need of an additional source of external heat for de-saturating the mother liquor for dissolution of fresh soda ash.
  • the fortified feed solution containing dissolved soda ash is filtered and returned to the crystallizer directly or via the heat exchanger.
  • the heat requirements for dissolving soda ash in the heated mother liquor are much less then the heat that would be required for first dissolving the fresh soda ash in water and then providing additional heat for evaporation of the solvent water so added.
  • the fines streams so withdrawn from the crystallizer may then be charged to the centrifuge and drying system and then packaged as fine product. Drying is slower and dust losses are higher but this is an advantageous improvement compared to the production of powdered bicarbonate by milling of larger crystals to meet the demand for fine grades of sodium bicarbonate.
  • the slurry of larger crystals removed from the crystallizer is centrifuged to separate the mother liquor from the product crystals.
  • the centrifuged crystals are suitably washed and transferred to a rotary dryer where residual moisture is volatilized. In the rotary dryer, the crystals are dried at relatively low temperature in a C0 atmosphere to prevent decomposition of the bicarbonate to carbonate by loss of C0
  • the centrifuge is suitably a variable speed, automatic-batch type which minimizes the breakage of crystals and increases the production of coarse granular grades.
  • the dry bicarbonate from the dryer is transferred to screening and milling operations by screw conveyors, bucket elevators or by an integral air-veyor system whereby the product is entrained in the dryer exhaust air stream and transported to the screens by air ducts.
  • Finer grades of bicarbonate are suitably produced from the coarser grades grown in the crystallizer by milling and classification in a closed-loop system.
  • substantially all of the heat is removed by evaporative cooling of the droplets of dispersed liquor in the CO absorber, including the exothermic heat of solution of the soda ash, the exothermic heat of crystallization of the bicarbonate, the exothermic heat of absorption of CO and any heat from external sources required to dissolve the dry soda ash in recycled mother liquor.
  • This process avoids surface coolers such as shell-and-tube coolers in the suspension recycle circuit supplying the spray nozzles.
  • a particular advantage of the process of the present invention resides in providing a large, e.g., to hours of production, dynamic reserve of sodium bicarbonate crystals in the crystallizer suspension.
  • This reserve serves to slow the rate of crystal growth and to assure the production of coarse crystals of high strength. Substantial fluctuations in this reserve over periods of several hours do not adversely affect crystal quality.
  • This reserve stabilizes the production rate over extended periods of time and effects economies in other sections of the plant. Intermediate surge silos between major sections of the plant are therefore unnecessary.
  • the slurry transfer rate from the crystallizer to the centrifuges is suitably adjusted to accommodate normal batch-wise operation.
  • a plurality of centrifuges including a spare unit is advantageous to minimize the magnitude of surges in crystal flow rate through the drier and to assure continuity of flow to the mills in the event of centrifuge breakdown.
  • the reserve of crystals in conventional bicarbonate towers covers only about 2.5 hours of tower product. This reserve must be maintained in order to maintain productivity and cannot be varied to stabilize subsequent plant production. Surge silos are required to stabilize flow through screens and mills whereas such silos are necessary in the process of the present invention.
  • CO concentration in the tower suitably varies from 4 to 100 percent, preferably about 8 to 40 percent.
  • Novel nozzle design permits operation with 4 to 5 percent C0 C0 supplied is suitably boiler stack gas containing 9 to percent CO or, for example, a plant stream containing 95 percent CO and from 0.5-1.5 percent H such as is recovered from ammonia synthesis plants.
  • Normally gas pressure in the carbonator prevents intake of air and no hazard is presented by the selective absorption of CO
  • EXAMPLE I In an absorber-crystallizer feet in diameter and 75 feet high a suitable plurality of spray nozzles are arranged in opposing groups at an elevation of about feet above the bottom of the tower and provide spray interaction which increases the rate of CO absorption. Residence time of the spray droplets is 2 to 3 seconds at a nozzle pressure of 30 psig.
  • Suitable spray nozzles of the 30 to solid cone or hollow cone type having rated capacties of to 200 gpm (gallons per minute) operating at discharge pressures of about 15 to 30 psig provide satisfactory absorption rates of C0,.
  • the nozzles are directed to provide maximum interaction to enhance CO, absorption. Enhancement of the CO, absorption rate from gases low in CO, concentration is effected by design or selection of nozzles which disperse the recirculated suspension into smaller droplets. Gas dispersion nozzles are particularly effective in generating small drops but also require the dissipation of larger amount of pumping and compression energy.
  • a funnel-shaped conical baffle is sealed internally to the side walls with the top of the funnel at an elevation of 25 feet above the bottom of the tower and the bottom of the funnel at an elevation of 15 feet.
  • the bottom of the funnel has a diameter of 12 feet.
  • the concentric zone between this funnel and the tower wall provides a quiescent elutriation zone also intended to generate crystal free mother liquor.
  • Ports fitted with throttle plates near the upper edge of this baffle provide for the regulation of the flow of clarified mother liquor upwardly in the peripheral zone of the baffle.
  • Suspension circulating pump intakes (2) are provided at an elevation of 1 foot above the bottom and these discharge in a battery of spray nozzles similar to those previously described at an elevation of 30 feet above the bottom. Fragments of scale too large to pass the smallest orifice in the spray nozzles are restrained by a large cylindrical screen affixed to the bottom of the conical elutriation zone baffle and extending to the bottom of the tower. Recirculated suspension must pass through the screen to reach the pump intakes. Suspension for supplying the crystal centrifuges is preferably drawn from a dynamic suspension zone in the bottom of the tower.
  • a stream of crystal free mother liquor is removed from the elutriation zone and heated in the regenerative heat exchanger to provide a solution unsaturated in soda ash in which fresh soda ash is dissolved.
  • the regenerative heat exchanger is particularly advantageous in reducing auxiliary steam requirements for dissolving the ash but cooling is controlled to maintain the temperature of the returning fortified feed liquor above saturation temperature.
  • Connections for drawing mother liquor with variable concentrations of fine crystal and nuclei are also provided at an intermediate level of about 17 feet. The concentration of crystals in this stream is dependent on the total rate of flow of crystal-free mother liquor through the elutriation zone. Crystals in this stream may be recovered as fine product or they may also be destroyed by reheating in the feed dissolving circuit.
  • a suitable rotary dryer is 6 feet in diameter and 25 feet long. It has a capacity of 15,000 pounds per hour of sodium bicarbonate. Hot air enriched with recycle CO entering at 450F. flows cocurrently through the dryer. This minimized air velocity, dust entrainment and bicarbonate decomposition. The maximum discharge temperature of the bicarbonate is C. (about- 158F.). Internal dryer flighting improves heat transfer and contributes strength to the dryer shell.
  • EXAMPLE ll Absorber Operation In an absorber-crystallizer tower having a diameter of 20 feet and an overall height of 76 feet, the cylindrical body has a height of 44 feet with an 18 foot high conical roof and a 14 foot deep conical bottom reducing the diameter to 6 feet. The steep roof angle minimizes scale formation on this surface and the concical bottom minimizes crystal sedimentation on the walls.
  • the top 30 feet of the cylindrical body of the tower is the absorption zone and the bottom 28 feet of the tower is the crystallizer and classification zone. The remaining 18 feet constitutes the conical roof.
  • the slurry of fine crystals of NaHCO was removed from the crystallizer at atemperature of 57C. (135F.) and heated in the heat exchanger to 66C. (150.8F.).
  • the exothermic heat of solution of the ash raised the solution temperatue to 68C. (154.4F.).
  • hot fortified feed liquor from the filter was charged to the heat exchanger at 68C. (154.4F.) and was cooled to 59C. (138.2F.) before returning to the crystallizer.
  • the CO atmosphere in the absorber-crystallizer was provided by feeding washed stack gas containing 7,997 lb./hr. of CO 5,009 lb./hr. of water, 1,683 lb./hr. of O and 42,560 lb./hr. of N
  • the vent gas from the absorber contained 4,597 lb./hr. of CO 6,457 lb./hr. of water, 1,683 lb./hr. of O and 42,560 lb./hr. of N
  • 3,400 lb./hr. of CO was absorbed and 1,448 lb./hr. of water was evaporated.
  • a recycle stream of liquor and crystals from the bottom of the crystallizer was circulated at a rate of 10,000 gallons per minute to the lower bank of sprays in the absorber zone to induce absorption of 3,400 lb./hr. of CO Coarse crystal slurry was transferred from the bottom of the crystallization zone to the centrifuges and amounted to 12,600 lb./hr. of Nal-lCO crystals in 37,600 lb./hr. of mother liquor.
  • the wet bicarbonate removed from the centrifuges amounted to 13,000 lb./hr. holding 400 lb./hr. of water. This was dried and screened to provide 12,600 lb./hr. of coarse, crystalline sodium bicarbonate product having a bulk density of 55 lb./ft. It showed the following chemical and mesh analysis:
  • a method for producing sodium bicarbonate by carbonating sodium carbonate in an absorbercrystallizer to precipitate sodium bicarbonate crystals which comprises: 7
  • a method for producing sodium bicarbonate by carbonating sodium carbonate in an absorbercrystallizer to precipitate sodium bicarbonate crystals which comprises:

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
US305397A 1971-12-29 1972-11-10 Sodium bicarbonate production Expired - Lifetime US3870784A (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
US305397A US3870784A (en) 1971-12-29 1972-11-10 Sodium bicarbonate production
CA158,713A CA966975A (en) 1971-12-29 1972-12-13 Sodium bicarbonate production
GB5748572A GB1402158A (en) 1971-12-29 1972-12-13 Sodium bicarbonate production
FR7246761A FR2169886B1 (de) 1971-12-29 1972-12-28
JP48004344A JPS4879199A (de) 1971-12-29 1972-12-28
DE2264087A DE2264087A1 (de) 1971-12-29 1972-12-29 Verfahren zur herstellung von natriumbicarbonat

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US21356271A 1971-12-29 1971-12-29
US305397A US3870784A (en) 1971-12-29 1972-11-10 Sodium bicarbonate production

Publications (1)

Publication Number Publication Date
US3870784A true US3870784A (en) 1975-03-11

Family

ID=26908191

Family Applications (1)

Application Number Title Priority Date Filing Date
US305397A Expired - Lifetime US3870784A (en) 1971-12-29 1972-11-10 Sodium bicarbonate production

Country Status (6)

Country Link
US (1) US3870784A (de)
JP (1) JPS4879199A (de)
CA (1) CA966975A (de)
DE (1) DE2264087A1 (de)
FR (1) FR2169886B1 (de)
GB (1) GB1402158A (de)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3975503A (en) * 1970-12-08 1976-08-17 Kali-Chemie Aktiengesellschaft Method for producing alkali carbonate
US4007082A (en) * 1975-08-15 1977-02-08 Hooker Chemicals & Plastics Corporation Kraft mill recovery system
WO1994026664A1 (en) * 1993-05-06 1994-11-24 Church & Dwight Co., Inc. Large potassium bicarbonate crystals and process for the preparation thereof
US6352653B1 (en) * 1998-11-26 2002-03-05 Asahi Glass Company Ltd. Acid component-removing agent, method for producing it and method for removing acid components
US6609761B1 (en) 1999-01-08 2003-08-26 American Soda, Llp Sodium carbonate and sodium bicarbonate production from nahcolitic oil shale
US6699447B1 (en) 1999-01-08 2004-03-02 American Soda, Llp Sodium bicarbonate production from nahcolite
US9695059B2 (en) 2011-12-21 2017-07-04 Solvay Sa Process for preparing sodium bicarbonate particles
CN109095480A (zh) * 2018-10-19 2018-12-28 天津渤化永利化工股份有限公司 一种注射级小苏打联产口服级小苏打的装置及方法
CN111704149A (zh) * 2020-05-27 2020-09-25 山东海天生物化工有限公司 一种生产小苏打的工艺方法
CN112374510A (zh) * 2020-11-03 2021-02-19 山东海天生物化工有限公司 一种生产小苏打的新工艺
CN115650259A (zh) * 2022-10-28 2023-01-31 天津大学 大颗粒碳酸氢钠的制备方法及装置

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4724996B2 (ja) * 1999-08-24 2011-07-13 旭硝子株式会社 アルカリ金属炭酸水素塩の製造方法
JP5072919B2 (ja) * 2009-07-23 2012-11-14 日立造船株式会社 焼却炉からの焼却灰の処理装置および処理方法

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1619336A (en) * 1921-10-12 1927-03-01 West Virginia Pulp & Paper Co Process and apparatus for making concentrated carbon dioxide
US1865833A (en) * 1929-01-21 1932-07-05 Heinz H Chesny Process of forming sodium bicarbonate
US2142917A (en) * 1938-02-16 1939-01-03 Gustave T Reich Recovery of carbon dioxide
US2183324A (en) * 1938-02-16 1939-12-12 Gustave T Reich Recovery of carbon dioxide
US2256962A (en) * 1938-10-20 1941-09-23 Gustave T Reich Recovering carbon dioxide from flue gases
US2375922A (en) * 1938-10-05 1945-05-15 Jeremiassen Finn Treatment of solutions to obtain solid matter therefrom
US2883273A (en) * 1954-03-04 1959-04-21 Olin Mathieson Crystallization
US3531240A (en) * 1967-02-24 1970-09-29 Zieren Chemiebau Gmbh Dr A Process for the production of sodium bicarbonate and soda ash
US3647365A (en) * 1970-01-06 1972-03-07 Olin Corp Coarse light sodium bicarbonate
US3751560A (en) * 1970-04-08 1973-08-07 Zieren Chemiebau Gmbh Dr A Multi-stage process for the preparation of sodium bicarbonate

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1619336A (en) * 1921-10-12 1927-03-01 West Virginia Pulp & Paper Co Process and apparatus for making concentrated carbon dioxide
US1865833A (en) * 1929-01-21 1932-07-05 Heinz H Chesny Process of forming sodium bicarbonate
US2142917A (en) * 1938-02-16 1939-01-03 Gustave T Reich Recovery of carbon dioxide
US2183324A (en) * 1938-02-16 1939-12-12 Gustave T Reich Recovery of carbon dioxide
US2375922A (en) * 1938-10-05 1945-05-15 Jeremiassen Finn Treatment of solutions to obtain solid matter therefrom
US2256962A (en) * 1938-10-20 1941-09-23 Gustave T Reich Recovering carbon dioxide from flue gases
US2883273A (en) * 1954-03-04 1959-04-21 Olin Mathieson Crystallization
US3531240A (en) * 1967-02-24 1970-09-29 Zieren Chemiebau Gmbh Dr A Process for the production of sodium bicarbonate and soda ash
US3647365A (en) * 1970-01-06 1972-03-07 Olin Corp Coarse light sodium bicarbonate
US3751560A (en) * 1970-04-08 1973-08-07 Zieren Chemiebau Gmbh Dr A Multi-stage process for the preparation of sodium bicarbonate

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3975503A (en) * 1970-12-08 1976-08-17 Kali-Chemie Aktiengesellschaft Method for producing alkali carbonate
US4007082A (en) * 1975-08-15 1977-02-08 Hooker Chemicals & Plastics Corporation Kraft mill recovery system
WO1994026664A1 (en) * 1993-05-06 1994-11-24 Church & Dwight Co., Inc. Large potassium bicarbonate crystals and process for the preparation thereof
US5445805A (en) * 1993-05-06 1995-08-29 Church & Dwight Co., Inc. Large potassium bicarbonate crystals and process for the preparation thereof
AU682040B2 (en) * 1993-05-06 1997-09-18 Church & Dwight Company, Inc. Large potassium bicarbonate crystals and process for the preparation thereof
US6352653B1 (en) * 1998-11-26 2002-03-05 Asahi Glass Company Ltd. Acid component-removing agent, method for producing it and method for removing acid components
US6609761B1 (en) 1999-01-08 2003-08-26 American Soda, Llp Sodium carbonate and sodium bicarbonate production from nahcolitic oil shale
US6699447B1 (en) 1999-01-08 2004-03-02 American Soda, Llp Sodium bicarbonate production from nahcolite
US9695059B2 (en) 2011-12-21 2017-07-04 Solvay Sa Process for preparing sodium bicarbonate particles
CN109095480A (zh) * 2018-10-19 2018-12-28 天津渤化永利化工股份有限公司 一种注射级小苏打联产口服级小苏打的装置及方法
CN111704149A (zh) * 2020-05-27 2020-09-25 山东海天生物化工有限公司 一种生产小苏打的工艺方法
CN112374510A (zh) * 2020-11-03 2021-02-19 山东海天生物化工有限公司 一种生产小苏打的新工艺
CN115650259A (zh) * 2022-10-28 2023-01-31 天津大学 大颗粒碳酸氢钠的制备方法及装置
CN115650259B (zh) * 2022-10-28 2024-02-09 天津大学 大颗粒碳酸氢钠的制备方法及装置

Also Published As

Publication number Publication date
JPS4879199A (de) 1973-10-24
DE2264087A1 (de) 1973-07-12
FR2169886A1 (de) 1973-09-14
FR2169886B1 (de) 1976-08-27
CA966975A (en) 1975-05-06
GB1402158A (en) 1975-08-06

Similar Documents

Publication Publication Date Title
US3870784A (en) Sodium bicarbonate production
CN104477952B (zh) 燃煤锅炉烟气生产硫酸镁的装置与方法
US7173150B2 (en) Process for recovering terephthalic acid from pulverized product of spent polyethylene terephthalate and system for use in such process
US3309262A (en) Fluidized bed oxidation of waste liquors resulting from the digestion of cellulosic materials for paper making
US3627464A (en) Process for recovering so2 from waste gases
CN104556157B (zh) 烟气脱硫生产硫酸镁的装置与方法
US5624647A (en) Method for recovery of alkali values from trona using two-stage leaching
US3933977A (en) Process for producing sodium carbonate
US3975503A (en) Method for producing alkali carbonate
US4422900A (en) Spray drying apparatus for available chlorine-containing compounds
AU605911B2 (en) Process for production of sodium cyanide
US4291002A (en) Process for producing sodium carbonate from complex brines
US3780160A (en) Carbonation process for the manufacture of sodium bicarbonate
US3451767A (en) Process of preparing anhydrous sodium carbonate from crude sodium bicarbonate
CN101519383B (zh) 一种利用尿素联合生产蜜胺、纯碱和氯化铵的工艺
US3273961A (en) Regeneration of magnesium bisulphite pulping liquor and absorption of sulphur dioxide during regeneration
US3321268A (en) Conversion of caustic soda to soda ash
US3751560A (en) Multi-stage process for the preparation of sodium bicarbonate
US3314748A (en) Production of dense soda ash
US2368901A (en) Ammonium sulphate production
US4003801A (en) Treatment of water vapor generated in concentrating an aqueous urea solution
US4356162A (en) Method of obtaining alkali aluminates from aqueous solutions
US5976485A (en) Sodium metabisulfite process
CN104556159B (zh) 烟气脱硫生产亚硫酸镁的装置和方法
US4096235A (en) Process of producing magnesia with sulfuric acid recycle