Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
  • B01F23/30—Mixing gases with solids
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
  • B01F23/09—Mixing systems, i.e. flow charts or diagrams for components having more than two different of undetermined agglomeration states, e.g. supercritical states
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F23/00—Mixing according to the phases to be mixed, e.g. dispersing or emulsifying
  • B01F23/10—Mixing gases with gases
  • B01F23/12—Mixing gases with gases with vaporisation of a liquid
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F25/30—Injector mixers
  • B01F25/31—Injector mixers in conduits or tubes through which the main component flows
  • B01F25/313—Injector mixers in conduits or tubes through which the main component flows wherein additional components are introduced in the centre of the conduit
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F33/00—Other mixers; Mixing plants; Combinations of mixers
  • B01F33/80—Mixing plants; Combinations of mixers
  • B01F33/834—Mixing in several steps, e.g. successive steps
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F2025/91—Direction of flow or arrangement of feed and discharge openings
  • B01F2025/911—Axial flow
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
  • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
  • B01F2025/91—Direction of flow or arrangement of feed and discharge openings
  • B01F2025/918—Counter current flow, i.e. flows moving in opposite direction and colliding
• • 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
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/0318—Processes
  • Y10T137/0324—With control of flow by a condition or characteristic of a fluid
  • Y10T137/0329—Mixing of plural fluids of diverse characteristics or conditions
• • 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
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/8593—Systems
  • Y10T137/87571—Multiple inlet with single outlet
  • Y10T137/87652—With means to promote mixing or combining of plural fluids

Definitions

• the invention relates to a method and a device for injecting two-phase CO, "gas + solid" in a gaseous transfer medium.
• CO 2 is used in many industrial applications; carbonation, pH regulation, neutralization of basic agents are examples among others.
• Carbon dioxide can be injected into a liquid medium or a gaseous medium.
• CO 2 is injected in gaseous form, or liquid depending on the case.
• EP 0 631 846 describes an apparatus intended to produce an aerosol for cleaning the interior surfaces of a tool chamber.
• EP 0 288 263 describes an apparatus for removing small particles from the surface of a substrate using a mixture of solid and gaseous carbon dioxide.
• US 4,389,820 describes a machine intended to generate a flow of accelerated sublimable particles for surface stripping.
• the use of CO 2 prevents surface contamination as well as atmospheric contamination.
• FR 2 198 778 describes a process and an apparatus for the preparation of foundry molds, a process in which carbon dioxide gas is used for the delivery of gaseous components in catalytic quantity, both during the gasification of the mixture of liquid chemical components and when adjusting the quantities of components to be added.
• An object of the present invention is to provide a solution to the problem of injecting carbon dioxide, especially in large quantities, into chambers containing a reactive or non-reactive gaseous medium, in transit under pressure.
• Another object is to propose an injection device capable of implementing this process.
• the invention relates first of all to a method of injecting carbon dioxide into a gaseous medium under transfer under pressure to be treated, present inside an enclosure, from liquid carbon dioxide; the process comprising the steps of: - transformation of the liquid carbon dioxide into two-phase "gas + solid" carbon dioxide by a direct expansion device,
• the carbon dioxide injected is in the "gas + solid" form, the injection takes place directly into the gaseous medium to be treated, through a wall of the enclosure which contains the medium to be treated.
• the enclosure may for example be a pipe or pipe present in a circuit.
• the transformation of liquid carbon dioxide into two-phase carbon dioxide involves a direct expansion device called cryogenic expansion.
• the device, of the variable flow valve type first causes a restriction in the flow of the fluid, then an increase in the flow diameter has the effect of relaxing the gas causing a loss of pressure so that the pressure in output of the device corresponds to that of the triple point of CO 2 .
• Liquid CO 2 is transformed into a mixture of CO 2 gas and solid CO 2 (dry ice).
• the process of the invention uses a cryogenic fluid with a density at least twenty times greater than its gas phase.
• the injection of carbon dioxide involves an injector which is inserted into the wall of the enclosure and transfers the "gas + solid" mixture to the center of the transfer channel for the gaseous medium.
• the injection of a gas inerting in carbon dioxide, at the outlet of the cryogenic valve prevents blockages at the outlet of said valve and at the outlet of injector, in the gaseous medium.
• the inerting gas ensuring a gas sweep at the level of the various elements of the device where the two- phase CO 2 circulates, prevents pollution by foreign bodies, in particular humidity, and prevents the accumulation of carbon dioxide snow at points where the geometry its circulation would be difficult without entrainment by the inerting gas.
• Liquid CO 2 is made available at a pressure generally between 10.10 5 and 22.10 5 Pa (i.e. between 10 and 22 bars) and at a temperature generally between -35 ° C and -20 ° C.
• the two-phase carbon dioxide is injected in such a way that it is injected into the heart of the gaseous medium and distributed partly in co-current and partly in counter-current to the gas flow.
• injecting carbon dioxide into the heart of the gas that is to say into the gas stream far from the walls, ensures the best possible mixing and entrainment of CO 2 , thus preventing its accumulation.
• the risk of formation of plugs is very great given the temperature of this CO 2 (-80 ° C), it is therefore essential to immediately disperse it in the gaseous medium to be treated.
• the presence of the inerting gas injected into the two- phase CO 2 according to the invention also makes it possible to limit the risk of blockages.
• This inerting gas must be inert vis-à-vis the chemical species present as well as regulatory bodies (flow control valves, injector specific to the invention, etc.). It is particularly advantageous to use as inerting gas carbon dioxide originating from the vaporization of a fraction of the liquid carbon dioxide made available, and taken upstream of the cryogenic expansion. It should be noted that C0 2 which does not introduce a new chemical species can by extension also be considered as an inert gas.
• the quantity of carbon dioxide injected is preferably regulated as a function of a set point of a physical or chemical parameter to be reached, the measurement of this parameter is carried out in the gaseous medium, downstream of the injection point.
• cryogenic valve with variable flow of the invention is controlled as a function of this instruction.
• an all-or-nothing cryogenic safety valve can also be placed upstream of the variable-flow cryogenic valve to cut off the supply of liquid CO 2 in the event of a malfunction, for example if the pressure is too high. high in the gaseous medium to be treated, if the temperature is too low or if another parameter, considered to be major, has exceeded an alert threshold.
• the operator of the installation can also order this valve. When the power supply to the cryogenic valve with variable flow is cut, the protection of the sensitive elements of the device by a low flow of the inerting gas is maintained.
• the invention relates to a process for enriching a gas stream with carbon dioxide from liquid carbon dioxide.
• the invention also relates to a device for injecting carbon dioxide for implementing one of the methods as defined above, characterized in that it comprises:
• variable-flow expansion valve intended to be supplied with liquid carbon dioxide
• injector inserted into a wall of the enclosure and penetrating into the heart of the gaseous medium
• the end of the injector consists of:
• the injector enters the enclosure over a length equivalent to half the width of said enclosure and according to a preferred variant, the device comprises for supplying inerting gas to the injection device, upstream cryogenic expansion device, means for sampling and vaporizing a fraction of the liquid carbon dioxide made available.
• the device can therefore operate by being connected to a single carbon dioxide supply source. It is also possible to use an inert gas present at the place of application or compressed air, it being understood that the inerting gas must not modify the behavior of the mixture obtained, and must not be contraindicated for the material. .
• An embodiment of the invention is given by way of nonlimiting example, illustrated by Figure 1 which is a schematic view of a device according to the invention and by Figures 2 and 2A which show an example of an injector according to the invention, the
• Figure 2A being a sectional view along the axis AA of the end of the injector of Figure 2.
• the injection device 1 is intended to supply two-phase carbon dioxide "gas + liquid" in a gaseous medium 2, under transfer under pressure in an enclosure 3, and this from a storage tank 4 of carbon dioxide liquid in which the liquid carbon dioxide is stored at a pressure between 14.10 5 and 20.10 5 Pa (i.e. between 14 and 20 bars) and at a temperature between -35 ° C and -20 ° C
• the device 1 comprises a liquid CO 2 supply line formed by a liquid line 5 extending from the reservoir 4 to a cryogenic valve with variable flow rate 6 which regulates a parameter "A" measured in the medium gas 2 downstream of the injection point.
• a filter 7 fitted with a stainless steel filter cartridge is placed upstream of the valve 6, it filters the liquid carbon dioxide in order to protect the valve seat from solid impurities which may be present in the pipes.
• an all-or-nothing type cryogenic safety valve 8 which cuts off the cryogenic CO 2 supply to the valve 6 when the control member 9 detects a overshoot of a safety parameter under control.
• a cryogenic expansion valve not shown in the Figure, protects the line downstream of the safety valve 8 after the latter has closed.
• the device 1 further comprises a line for supplying inerting gas, which in this case is gaseous CO 2 ; the line is formed in the order of a vaporizer 10, a pressure reducer 11, a manually adjusted flow valve 12, a flow meter with transmitter 13 and a non-return valve, 14.
• a line for supplying inerting gas which in this case is gaseous CO 2 ; the line is formed in the order of a vaporizer 10, a pressure reducer 11, a manually adjusted flow valve 12, a flow meter with transmitter 13 and a non-return valve, 14.
• a tee 15, supplied in the upper part with two- phase CO 2 coming from the ejector situated at the outlet of the valve 6, on the side in inerting gas (gaseous CO 2 ) is connected in the lower part to an injector 16 ensuring the injection of the two- phase CO 2 mixture into the gaseous medium 2 by transfer under pressure into the enclosure 3.
• the injector 16 transfers the CO 2 to the center of the gaseous medium transfer pipe.
• the interior of the tee 15 and of the injector 16 are protected from the medium to be treated by means of a low but permanent flow rate of the inerting gas.
• a control and regulation unit for the "A" parameter measures the value of the "A” parameter in the transfer line, processes - via the control device 9 - the signal received from “A” as well as the signals which come from the various safety parameters monitored (temperature and pressure of the gaseous medium to be treated, etc.).
• the opening level of the cryogenic valve with variable flow rate 6 to ensure that the parameter "A” is maintained at its set value; it also controls the closing of the cryogenic safety valve 8 in the event of a major fault affecting a safety parameter, or in the event of refusal of processing authorization on the part of the operator, as well as the opening or closing of the vent valve depending on the operating mode, generally synchronous with the other valves.
• the injector 16 is supplied with two- phase CO 2 coming from the ejector 17 at the outlet of the valve 6 and with inerting gas consisting of gaseous C0 2 . This supply is made via the tee 15 which receives the inerting C0 2 at the side inlet 18 and the two- phase CO 2 from 17 in the upper part.
• the injector 16 made of a heat-insulating material, for example made of polysulfone, conducts the "gas + solid" mixture towards the center of the pipe 3 for transferring the gaseous medium 2.
• the injector 16 is provided: - at its end with a deflector 19 with two slopes, forming an angle of 60 ° to orient part of the two- phase CO 2 against the current of the gaseous medium 2 in circulation, and the other part co-current
• the process of the invention is implemented for enriching CO 2 with natural gas combustion fumes.
• the parameter "A" to be regulated is the CO 2 content of these fumes. Initially at approximately 8% CO 2 , the fumes are enriched by the process of the invention up to contents of between 12 and 18%, for their subsequent use in a papermaking process.
• the smoke flow is around 12,000 m 3 / h.
• the amount of CO 2 used is around 1,200 m 3 / h CO 2 (gas equivalent) to reach 16% CO 2 in the flue gases.
• the fumes thus enriched are intended in particular for the manufacture of calcium carbonate.
• the presence of water vapor in these fumes creates, due to the interface between the hot fumes and the cryogenic source, problems linked to the risk of ice formation, in particular at the level of the lights of the injector. This risk is avoided thanks to the permanent inerting of the injector by a neutral and dry gas.
• the method of the invention is particularly applicable in many fields using CO 2 as a raw material.
• the enrichment implemented according to the invention not using gaseous CO 2 emerges from the dimensional constraints and the drawbacks which are linked to it.
• the invention is thus particularly suitable for industrial installations having fumes containing CO 2 , a polluting agent in the state, and moreover using CO 2 as a raw material.
• the method of the invention can also be used in cases where it is desired to treat CO 2 with a gaseous transfer medium.
• the process of the invention can thus be applied advantageously to the CO 2 enrichment of fumes for the manufacture of calcium carbonate for the paper industry.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Carbon And Carbon Compounds (AREA)
• Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Physical Or Chemical Processes And Apparatus (AREA)
• Separation Using Semi-Permeable Membranes (AREA)
• Catalysts (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=29763742

Family Applications (1)

Country Status (10)

Families Citing this family (6)

Family Cites Families (9)

• 2002
  • 2002-07-11 FR FR0208734A patent/FR2842123B1/fr not_active Expired - Fee Related
• 2003
  • 2003-07-07 EP EP03763931A patent/EP1534414B1/de not_active Expired - Lifetime
  • 2003-07-07 AU AU2003263267A patent/AU2003263267A1/en not_active Abandoned
  • 2003-07-07 CA CA 2490662 patent/CA2490662C/fr not_active Expired - Fee Related
  • 2003-07-07 WO PCT/FR2003/002097 patent/WO2004007061A2/fr active Application Filing
  • 2003-07-07 US US10/521,011 patent/US7648569B2/en not_active Expired - Fee Related
  • 2003-07-07 DE DE60329111T patent/DE60329111D1/de not_active Expired - Lifetime
  • 2003-07-07 AT AT03763931T patent/ATE441472T1/de not_active IP Right Cessation
  • 2003-07-07 BR BRPI0312329-4A patent/BR0312329B1/pt not_active IP Right Cessation
  • 2003-07-07 JP JP2004520728A patent/JP2005532161A/ja active Pending

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events