Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D1/00—Evaporating
  • B01D1/28—Evaporating with vapour compression
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D1/00—Evaporating
  • B01D1/0011—Heating features
  • B01D1/0041—Use of fluids
  • B01D1/0047—Use of fluids in a closed circuit
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
  • B01D5/0033—Other features
  • B01D5/0039—Recuperation of heat, e.g. use of heat pump(s), compression
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
  • B01D5/0078—Condensation of vapours; Recovering volatile solvents by condensation characterised by auxiliary systems or arrangements
  • B01D5/009—Collecting, removing and/or treatment of the condensate
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/02—Treatment of water, waste water, or sewage by heating
  • C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
  • C02F1/041—Treatment of water, waste water, or sewage by heating by distillation or evaporation by means of vapour compression
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2303/00—Specific treatment goals
  • C02F2303/12—Prevention of foaming

Definitions

• the invention relates to an evaporator with mechanical vapor compression.
• the invention more particularly relates to an evaporator with mechanical vapor compression, of the type which comprises an inlet of an effluent fluid to be treated supplying a separator which is intended to separate the fluid into concentrate and vapor, said separator comprising a demister intended for separating effluent particles from the vapor obtained, said separator supplying on the one hand concentrates an inlet of a high-pressure circulation pump whose output selectively supplies a concentrate outlet and an inlet of a heat exchanger with an outlet feeding again the separator, said separator supplying on the other hand with steam an inlet of a booster element whose outlet delivers steam through exchange elements of the exchanger to transform the steam into a distillate which feeds a inlet of a countercurrent exchanger for heating the effluent fluid prior to its introduction into the s distributor, whose outlet allows the recovery of the distillate.
• Such an evaporator has a recurring problem consisting in the spontaneous formation of foam in the separator.
• the high-pressure circulation pump has the role of circulating at high speed the effluent concentrate to be treated, for example dirty water, through the exchange elements of the exchanger to avoid that the effluent stagnates there and leaves there deposits by a well-known phenomenon of cooking.
• foam forms above the level of concentrate in the separator and bubbles form below the concentration level of said separator.
• the foam pollutes the separator, and in particular the vapors that feed the booster element before being introduced between the elements of the exchanger to form the distillate.
• the bubbles present in the concentrate can, in turn, be sucked back by the high pressure pump and cause cavitation phenomena in the pump.
• such an exchanger comprises an inlet in the body of the separator which is intended to allow the introduction of an antifoam compound partially to overcome this disadvantage.
• the invention overcomes this disadvantage by providing an evaporator provided with mechanical means to prevent the formation of foam and bubbles.
• the invention proposes an evaporator of the type described above, characterized in that an expansion device is interposed between an outlet of the exchanger and an inlet of the separator to limit the pressure of the concentrate from the front exchanger. its reintroduction into the separator, in order to limit the phenomena of formation of foam and bubbles in the separator.
• the expansion device comprises at least one flow restriction element, the flow restriction element is interposed at the junction of a first condenser connected to the outlet of the exchanger and a second inlet duct of the separator,
• the first duct comprises a flange for fixing a calibrator corresponding to a flange for fixing the second duct, the said ducts being assembled to one another by means of annular flanges;
• the internal diameter is greater than the external diameter of the condu ces and lower than the diameter of the flanges, which are supported on the backs of the associated flanges and are tightened against each other by means of screws, and
• the flow restriction element comprises at least one washer, of an outside diameter corresponding to that of the flanges and of an internal diameter less than the internal diameter of the condu ities, that is interposed between the flanges and clamped between said flanges by the flanges,
• the second inlet duct of the separator opens into the cylindrical body of said separator via a spray nozzle arranged substantially at mid-height of the separator body,
• the spray nozzle comprises an end of the second duct, oriented vertically downwards, which opens out through a first annular flange, opposite which is arranged with clearance a second annular flange of the same diameter, to ensure a radial spray; iale the concentrate between the flanges so as to orient it radially against the internal walls of the body of the separator to prevent the formation of foam inside the separator, - the booster element consists of a compressor, including with lobes,
• FIG. 1 is a diagrammatic view of an evaporator according to FIG. invention
• FIG. 2 is a side view of an evaporator according to the invention illustrating the deposition of the expansion device and the spray nozzle;
• FIG. 3 is a detailed view showing the detent device corresponding to the reference frame I of FIG. 2;
• FIG. 1 shows an evaporator 10 with mechanical vapor compression.
• the evaporator 10 comprises an inlet 12 of an effluent fluid to be treated. This input 1 2 feeds a separator 14 which is intended to separate the flu ide concentrate 16 and steam 18.
• the separator 14 comprises in particular in its body 22 a desiccant 20 that is intended to separate effluent particles from the steam 18 obtained.
• the separator 14 supplies a concentrate 24 with an inlet 24 of a high-pressure circulation pump 26, an outlet 28 of which selectively feeds a concentrate outlet 30 and / or an inlet 32 of an exchanger 34 of which an outlet 36 again feeds the separator 14 in order to further reduce the concentrate.
• the high pressure circulation pump has the role of circulating at high speed the effluent concentrate to be treated, for example dirty water, through the exchange elements 44. the exchanger 34 to prevent the effluent stagnates there and leaves deposits by a well-known cooking phenomenon.
• the separator 14 supplies steam to an inlet 38 of a booster element 40 whose outlet 42 delivers steam through exchange elements 44 of the exchanger 34.
• the overpressure of the steam in the booster element 40 makes it possible to increase the enthalpy of the vapor, which it can then return to the exchange elements 44 of the exchanger 34, in order to increase the enthalpy of the concentrate reinjected into the separator 14.
• An outlet 50 of the countercurrent exchanger allows the recovery of the distillate.
• the invention proposes an evaporator 10 provided with mechanical means intended to limit the formation of foam and bubbles in the separator and thus to facilitate evaporation in the entire piping of the evaporator 10.
• the invention proposes an evaporator 10 of the type described above, characterized in that a device 54 for expansion is interposed between the outlet 36 of the exchanger 34 and an inlet 57 of the separator 14 to limit the pressure of the concentrate. from the heat exchanger 34 before its reintroduction into the separator 14, in order to limit the phenomena of foam formation in the separator 14.
• the expansion device 54 comprises at least one flow restriction element. This configuration is not limiting of the invention, and other means could be used to limit the pressure exiting the exchanger 34.
• the flow restriction element 54 is interposed at the junction of a first duct 56 connected to the outlet of the exchanger and a second inlet duct 58 supplying the inlet 57. separator 14.
• the first duct 56 comprises a flange 60 for fixing a diameter corresponding to a flange 62 for fixing the second duct 58, said ducts being assembled to each other via annular flanges 65, 66 associated with an internal diameter D 6 o greater than the external diameter D 5 658 of the ducts 56, 58 and smaller than the diameter D 6 oe 2 of the flanges 60, 62, which bear against the back of the flanges 60, 62 associated and are tightened against each other by means of screws (not shown) of axis "V".
• the flow restriction element comprises at least one washer 64, of an external diameter corresponding to the diameter D 6 o62 collars 60, 62 and an inner diameter D 64 less than the internal diameter dsess ducts 56, 58.
• This washer 64 is interposed between the flanges 60, 62 and is clamped between said flanges 60, 62 by the flanges 65, 66.
• a seal 68, 70 is interposed between each face of the washer 64 and the collar 60, 62 of the first or second conduit 56, 58.
• the second inlet duct 58 of the separator opens inside the cylindrical body 22 of said separator 14 via at least one spray nozzle 72 arranged substantially half way up. height of the body 22 of the separator 14.
• Each spray nozzle 72 is also advantageously shaped to prevent foaming.
• each nozzle 72 has an end 74 of the second duct 58, oriented vertically downwards, which opens through a first annular flange 76.
• this first annular flange 76 is arranged with clearance a second annular flange 78 of the same diameter.
• This configuration makes it possible to ensure radial spraying of the concentrate between the flanges 76, 78, as represented by the arrows of FIG. 2, so as to orient it radially against the internal walls 80 of the body 22 of the separator 14.
• the concentrate licks thus said walls 80, which prevents the formation of foam inside the separator 14.
• the booster element 40 consists of a compressor, including lobes.
• the booster 40 may also be a side channel booster. It will also be noted that the elements 44 of the exchanger 34 are preferably horizontal tubes, which make it possible to limit the fouling.
• the invention therefore proposes an evaporator making it possible to substantially limit the formation of foam and bubbles in the separator 14 and thus to limit the pollution of the distillate 14 and of all the elements in which it circulates.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Life Sciences & Earth Sciences (AREA)
• Hydrology & Water Resources (AREA)
• Engineering & Computer Science (AREA)
• Environmental & Geological Engineering (AREA)
• Water Supply & Treatment (AREA)
• Organic Chemistry (AREA)
• Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=40039876

Family Applications (1)

Country Status (4)

Cited By (2)

Families Citing this family (4)

Family Cites Families (7)

• 2008
  • 2008-03-10 FR FR0851515A patent/FR2928276B1/fr active Active
• 2009
  • 2009-03-09 EP EP09719678A patent/EP2252384A1/de not_active Withdrawn
  • 2009-03-09 WO PCT/EP2009/052711 patent/WO2009112451A1/fr not_active Ceased
  • 2009-03-09 JP JP2010550153A patent/JP2011513058A/ja active Pending

Non-Patent Citations (1)

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