FR2621670A1 - VALVE BLOCK FOR PRESSURE VARIATION ADSORPTION FACILITIES FOR THE SEPARATION OF GASEOUS MIXTURES, IN PARTICULAR FOR THE EXTRACTION OF OXYGEN AND NITROGEN FROM AIR - Google Patents

Abstract

Characterized in that in the valve block the adsorber valves 2 assigned to an adsorber are connected together by an adsorber gas line 1 forming a series, the valve block having a recess at the adsorber valves 2 , the recesses forming part of the production gas pipes 1, a pipe 6 being introduced into the recesses leading each time through a branch 5 to a production gas pipe 4, pipe 6 forming with the recess an annular slot and the 'axis of the pipe 6 leading to the production gas pipe 4 intersecting the axis of the adsorber gas pipe 1. The invention relates to a valve block for pressure-varying adsorption plants, serving for separation gas mixtures, in particular for the extraction of oxygen and nitrogen from air.

Description

I "Valve block for adsorption plants at

  pressure variation, used for the separation of

  gaseous substances, in particular for the extraction of oxygen

ne and nitrogen from the air ".

  The invention is used for the control of pressure swing adsorption plants for separating gaseous mixtures by adsorption, in particular for extracting oxygen.

and nitrogen from the air.

  More specifically, the invention relates to a

  valve block for vacuum adsorption plants

  of pressure, consisting of several

  pneumatically actuated absorber tubes arranged in a block, valves connected to adsorbers by adsorber gas lines and with production gas lines for incoming flowing gases,

  respectively leaving the adsorbers.

  For the separation of gaseous mixtures,

  frequently uses the process by ad-

  sorption because of its economic nature and because of its efficiency. The processes working with a pressure variation have particularly made

  in recent times for this application.

  tion. In these processes, desorption of the adsorbent

  loaded is carried out by pressure drop, fall

  supplemented by the application of a rinsing gas

cage.

  The known vacuum adsorption plants

  pressure manifests have a plurality of

  pes for the control of gas flows. These valves greatly increase the expense in material and cost. Therefore, one is tempted to limit the expense from the valves. According to DE-OS 3 310 759, it is known for this purpose how to assemble, in a block of valves,

  the valves integrated in the connecting pipes

  mainly. The valve blocks are provided each time on the gas inlet and on the gas outlet of

  adsorber. Because of the valve blocks, the pipe

  The adsorption process is significantly limited. The constructive configuration of these valve blocks is however not described in the document DE-OS

3,310,759.

  The object of the invention is to limit the

  think in material and cost concerning the valves

  and the adsorber pipes in the

  pressure swing adsorption

  put a construction mode of small footprint installations and is characterized in that in

  the valve block, the adsorber valves

  adsorber are connected together

  adsorber gas stream forming a series, the valve block having a recess at the adsorber valves, the recesses forming a part of

  production lines, a pipe being introduced

  in the recesses each time leading through a branch to a production gas pipe, the pipe forming with the recess an annular slot and

  the axis of the pipe leading to the production gas pipe

  cutting off the axis of the adsorber gas line.

  The object of the invention is to develop a valve block for a pressure swing adsorption plant, in which the adsorber valves of

  all the adsorbers belonging to the installation of ad-

  pressure swing sorption provided on one side

  the adsorber are arranged next to each other

  in the smallest possible volume.

  The problem is solved according to the invention, in that the adsorber valves affected in the adsorber valve block are connected forming a

  series by an adsorber gas pipe. Each con-

  The adsorber gas stream leads from a valve block to an adsorber and opens into it on an adsorber side. Production gas lines also lead to the valve block, for gases flowing through the adsorber gas lines, entering into

  adsorbers or leaving adsorbers. The

  The adsorber rods are connected to the production gas lines by branches in the valve block and are generally cross-shaped. An adsorber valve opens or closes

  thus the connection between a production gas pipe

  and an adsorber gas line. The block of

  The valves have a recess on each of the valves

  adsorber pes; the recesses form part of the adsorber gas pipes. A pipe leading through a branch to a production gas line

  is introduced into each of the recesses,

  mant an annular cleft with the recess. The annular slot and the pipe form part of an adsorber valve. The axis of the pipe leading to the pipe of

  production gas and the axis of the

  sorbeur cut each time. In this way, it is possible for the gas leaving the production gas duct to flow into the adsorber gas duct, through the branching in the pipe and the recess. Because an adsorber gas pipe

  leads from each adsorber to the valve block, the name

  of the adsorber gas pipes located in

  the valve block corresponds to the number of adsorbers

  bers belonging to the pressure swing adsorption plant. On the side of the pipe, which is opposed to the

  production gas line, a mem-

  brane which is able to close the passage opening

  formed by the end of the pipe when it is

cited by control gas.

  Because the inlet port is part of an adsorber valve, the adsorber valve is

  in this closed way, when the membrane is

allowed by the control gas.

  In adsorption plants with variable

  three adsorber pressure units, adsorber gas lines and production gas lines

  mutually interchangeable by virtue of their

  on the valve block. This is why

  picks of adsorber gas can lead to the place

  production gas pipelines on the pressure block

  to the point where the production gas pipes

  exit into the valve block. On this occasion, the production gas lines are in

  this case arranged in a location on which the

  adsorber gas flows are provided. In this case, the adsorber valves in the production gas lines form a row in the valve block. In order to allow an automatic start of the plant, the adsorber valves through which the gas mixture (for example air) which has to be subjected to an adsorption process in the adsorbers enters the block of valves , are

  each time provided with a pressure booster.

  Such a pressure booster consists of a second membrane and a pressure element, both of which are arranged on the side of the diaphragm closing the passage opening which is opposed to the passage opening of the pressure relief valve. adsorber. The surface of the second membrane solicited by the control gas is on this occasion greater than the surface of the

  the orifice of passage of the adsorber valve. The the-

  pressure is provided between the two membranes and transmits the pressure exerted on the second diaphragm

  to the membrane disposed on the passage opening.

  Suitably, a balance valve

  pressure break is arranged in the valve block

  in each adsorber gas line, a balancing valve connected to the pressure equalizing valves of the other adsorber gas lines. In each adsorber gas line, the adsorber valves assigned to an adsorber and a valve

  pressure balances are disposed of this

  in the valve block. The latter is

  green when pressure balancing is required

kill between deu / adsorbers.

  A block of valves is each time assigned to an adsorber side of several adsorbers. A

  pressure swing adsorption plant pre-

thus feels two blocks of valves.

  For the purposes of the invention, the term "production gas pipes" means the pipes through which the production gases are fed to the valve blocks or are evacuated from the valve blocks. The production gases are the mixture of

  gas to be separated (eg air), the flushing gas

  ge, the residual gas and the gas obtained

  proximally pure (eg oxygen). On the contrary, adsorber gas pipes are understood to mean the pipes arranged between the adsorbers and the

valve blocks.

  Other improvements of the invention are characterized in that the number of adsorber gas pipes in it corresponding to the number of adsorbers belonging to the pressure swing adsorption plant; to the through-holes of the adsorber valves, membranes,

  carried out in such a way as to provide an ob-

  ration, are arranged on these; the adsorber valves provided for the entry of adsorption gas

  have a pressure amplifier; am-

  pressure intensifier consists of a second mem-

  brane and a pressure member disposed on the diaphragm side closing the passage opening opposite the passage opening of the adsorber valve, the surface of the second membrane urged by the control gas being on this occasion bigger than the

  surface of the through hole and the pres-

  sion being provided between the two membranes; the ramifications

  fications are made in the shape of a cross; a sou-

  pressure balancing valve is disposed therein, in each adsorber gas line, valve connected to the pressure equalizing valves of each of the other adsorber gas lines; three adsorber pressure swing adsorption plants, adsorber gas lines

  and the production gas lines are interchangeable

  mutable in their arrangement on the block

of valves.

  The valve block consists of

  suitable aluminum or thermoplastic material.

  In the latter case, such a block of valves may be

  manufactured by injection molding.

  The invention has the advantage of being economically

  important material and weight and a good presentation of the adsorber valves belonging to the installation. Example of embodiment: The invention is explained in detail using

  of an example of realization and a drawing, in the-

  which: FIG. 1 shows a longitudinal section in a valve block, FIG. 2 represents a cross section in a valve block, FIG. 3 is a representation in space.

  a valve block connected to the lower side of the adsorber

Beur.

  In a variable adsorption plant

  pressure, the oxygen must be extracted from the air

  with a volume concentration of about 82%.

  The installation has 3 adsorbers arranged vertically

  next to each other. In each case a valve block is connected by adsorber gas lines to the bottom and top sides of the adsorber. The two valve blocks have the same constructive configuration, only the type of gases supplied is different. We will describe accordingly the

  valve block assigned to the lower side of adsorber

  Beur. The valve block has the shape of a square on the square base surface. It consists

  aluminum. The 3 adsorber gas lines 1

  Binding 1 block of valves to the other side of one of each of the adsorbers lead - as is visible in Figure 3 - to the upper side of the valve block, therein. In the valve block, 3 valves

  adsorber 2 are each arranged in the con-

  adsorber gas lines 1, so that the valve block has a total of 9 adsorber valves. AT

  this occasion, 3 adsorber valves 2 form each

  that once a row on 3 outer surfaces of the block

  of valves. 3 adsorber valves 2 are thus dis-

  laid one behind the other, in each

  adsorber gas i located in the valve block.

  The valve block present at each valve

  The adsorber gas pipes 1 thus consist in the block of longitudinal bore valves and of the adsorber gas pipes 1.

recesses 3.

  The three production gas lines 4 through which different gases are passed to or from the valve block lead to the fourth outer surface of the valve block, in which

  no adsorber valve 2 is disposed. The provision

  of the production gas lines 4 is

  at right angles to the gas supply lines

  sorbeur 1. Production gas pipelines 4

  in the valve block there is a cross-shaped branch 5 from which 3 gas lines lead each time through the inlet pipe 6 to an adsorber valve 2. Each pipe 6 forms with a recess 3 an annular slot. The surface of the

  annular slot corresponds to the cross-sectional area

the pipe 6.

  The axis of one of each of the pipes 6 cuts to

  this opportunity an axis of an adsorber pipe 1.

  The three production gas lines 4 are thus divided into the valve block and each lead to three adsorber valves 2. In the open position of an adsorber valve 2, the gas from the gas line Production 4 can therefore flow in an adsorber gas line 1, where it can be the opposite. A membrane 7 is each time assigned to the pipe 6, at right angles to it, a membrane consisting of an elastic polyurethane. On the side of the membrane 7 opposite the pipes 6 is provided the control air line 8 leading to a control valve. The control valves are in the form of three-way valves. A lane is used for this purpose to deaerate the control air duct 8 in the case where the membrane is not

  not solicited by the control air.

  For greater clarity, the

  8 is not shown in FIG. 3. The arrangement of the membranes 7 with respect to the pipes 9 is such that, during the loading of the

  membranes 7 by the control air 8, the membrane 7

  the pipe 6 and thereby closes the gas passage. If the adsorber valve 2 is open, the gas flows from the adsorber gas pipe 1, through the annular slot, passing over the

  membrane 7, going into the pipe 6, or vice versa.

  On their outer side, the adsorber valves 2

  are provided with a valve cover across the-

  which passes the control air line 8. That is why the valve covers of FIGS.

3 are provided with reference 2.

  The adsorber valves 2 are thus made

  in the form of pneumatic valves closing

  when solicited by the control air.

  In another embodiment of the block

  valve, which is assigned to the upper side of the

  sorbeur (not shown in the drawing), besides the 3 adsorber valves 2, a pressure equalization valve is still arranged in the valve block, in each adsorber gas pipe 1 and connected by a gas pipe to the pressure equalizing valves of every other adsorber gas line

  1. These pressure balancing valves

  that once a series in each gas pipe ad-

  sorbeur 1, with the 3 adsorber valves. They are made in the same way as the adsorber valves 2. They are closed by soliciting the control gas during the operation of the installation

  pressure swing adsorption, the two valves

  pressure balancing weights affected by the balancing

  Pressure breaking is only open during pressure compensation between two adsorbers. At this time, all the adsorber valves 2 disposed in the two valve blocks are closed. In order to

  guarantee at start-up an opening and closing

  of the 3 adsorber valves 2 connected to the production gas line 4, through which the compressed air flows into the valve block, these

  adsorber valves 2 are provided with an amplification

  pressure transmitter. These pressure amplifiers consist of a second membrane disposed at a distance from the membrane 7 located on the passage orifice of the adsorber valve and a movable pressure element, provided between the two membranes. The surface of the second membrane urged by the control gas is larger than the surface of the passage opening of the adsorber valve 2. The pressure element transmits the pressure exerted on the second membrane 7 disposed on the passage opening. In this way, a low pressure is already enough to close the

  corresponding adsorber valves 2, when starting

rage of the installation.

  During the operation of the pressure swing adsorption plant, the compressed air passes through the central production gas line 4 of the lower valve block, the compressed air in front of which

  to be subjected to an adsorption process in an adsorption

  Beur. The compressed air arrives from the production gas line 4 to the branch 5 and then to the three pipes 6 and thus to the three adsorber valves 2. Two of the three adsorber valves 2 are closed due to the solicitation of the adsorber. compressed air in the control air line 8, the third adsorber valve 2 disposed in the adsorber line

  1, leading to the adsorber in which the process takes place.

  above adsorption, is open. The compressed air passes through the pipe 6 into the adsorber valve 2 open,

  by going on the membrane 7 in the recess 3 and

  bank of it by the adsorber gas pipe 1

  at the lower end of the adsorber in question.

  The solicitation of the membrane 7 by the control air

  of and thus the opening and closing of the valve

  adsorber 2 is effected by means of an electronic control

  in chronological order, the control air

  of being on this occasion each time brought to the

  of adsorber 2 by the control valves and by

the control air line 8.

  While the adsorption process takes place in an adsorber, there is desorption process in the second adsorber, with simultaneous rinsing and

  third adsorber is prepared for a new

  Oxygen rinse adsorption process approx.

  very pure. On this occasion, the flushing gas

  the third adsorber passes through an adjacent adsorber gas line, from above into the lower valve block, flows down into the interior of the valve block into this adsorber gas line 2 and goes to the lowest adsorber valve 2, which is open, while the two adsorber valves 2 which are above and arranged in this adsorber gas line i are closed, it flows through the adsorber valve 2 the lowest and so by the pipe 6 the lowest and by the lower branch 5, going into the

  lower production gas line 4. Driving

  The lower production gas stream 4 leads as a flushing gas conduit to the valve block assigned to the adsorber upper side and the adsorber side thereof in the second adsorber. The flushing gas leaving the second adsorber, then strongly contaminated with

  impurities comes from above also like the gas

  duel appearing during desorption, passing through the third adsorber gas pipe 1 and going into the valve block. In this gas line of this adsorber 1, only the adsorber valve 2 is open. Contaminated rinsing gas passes through the

  adsorber valve 2 superior and arrives in the ra-

  mification 5 superior. Because the other two adsorber valves 2 are closed, the contaminated rinsing gas can flow only through the upper production gas line 4, through which it flows.

  leaves the valve block and the adsorp-

  pressure variation. In this way,

  the 9 adsorber valves 2 of the valve block,

  during the adsorption process, 3 are open and 6

are closed.

  After completion of the adsorption process in this adsorber, there is a pressure equalization between the first and the third adsorber. At this moment, the 9 adsorber valves 2 of the block of

valves are closed.

  When pressure balancing is complete

  The following process of adsorption in the third adsorber follows. On this occasion, compressed air

  is also directed by the production gas line

  4 in the lower valve block,

  the air passing through the central branch 5, by means of

  that adsorber valve 2, which is arranged in the

  adsorber gas duct 1 leading to the third adsorber

  getter. The other two adsorber valves 2 cen-

  trales are closed on this occasion. The rinsing gas from the second adsorber passes through the adjacent adsorber pipe 1, coming from above into the block.

  of valves, flows inside the valve block

  weighed down in this adsorber gas line 1 towards the lower adsorber valve 2 which is open, while the two adsorber valves 2 which are disposed over it in this adsorber gas line are closed. he goes through the valve

  lower adsorber 2 and then through the branching

  lower level in the production gas line

  4 lower. The other two adsorption valves

  2 below located in the gas pipes

  adsorber 1 leading to the first adsorber and the third

  sth adsorber, are closed at this time. The gas of

  rinsing flowing in the production gas line

  4 is placed in the upper part of the first adsorber. It flows through the first adsorber, leaves at its lower part, in the third adsorber pipe 1 and then flows

  from the top in the valve block. In this

  here, only the upper adsorber valve 2 is

  green in this adsorber gas line 1. Contaminated rinse gas passes through the adsorber valve

  2 superior and arrives in the upper 5 branch.

  pool. Since the other two adsorption valves

  2 are closed, the contaminated rinsing gas flows only through the gas line

  4 out of the valve block.

  If the adsorption process is complete

  in the third adsorber, an equilibrium

  pressure with the second adsorber, followed by a new adsorption process

  in the second adsorber. On this occasion, the

  adsorber 2 need to control the flow of gas are opened again, respectively.

closed.

  The valve block that is assigned to the three

  adsorbers, with a volume each time

  very, itself has a volume of 2600 cm3. His

weight is 8600 g.

Claims (4)

  1 ') Valve block for adsorption plants with pressure variation, consisting of   several pneumatically operated adsorber valves   located in a block, valves connected to the adsorbers by adsorber gas lines and with production gas lines for the gases flowing on entering or leaving the   adsorbers, characterized in that in the block of   the adsorber valves (2) allocated to an ad-   sorbeur are connected together by a gas pipe   adsorber (1) forming a series, the block of   popes having a recess (3) at the inlet valves   separator (2), the recesses (3) forming a part of the production gas lines (1), a pipe (6) being introduced into the recesses (3) leading each time   branching (5) to a gas line of   ducting (45), pipe (6) forming with the recess (3) an annular slot and the axis of the pipe (6) leading to the production gas line (4) intersecting the axis of the adsorber gas duct (1).   2-) valve block according to claim 1, characterized in that the number of the pipes of   adsorber gas (1) in it corresponds to   which is one of the adsorbers belonging to   pressure swing adsorption system.   3 ') valve block according to any one   claims 1 or 2, characterized in that   orifices for the passage of adsorber valves (2), membranes (7), made in a manner likely to   provide a closure, are arranged thereon.   4 ') Valve block according to any one of   Claims 1 to 3, characterized in that the   adsorber valves (2) provided for gas inlet   adsorption are provided with a pressure amplifier   if we. Valve block according to Claim 4, characterized in that the pressure booster is composed of a second diaphragm and a pressure element arranged on the diaphragm side (7) closing the passage opening opposite to the orifice of passage of the adsorber valve (2), the surface of the second membrane urged by the control gas being at this time greater than the surface of the passage orifice and the pressure element being provided enter both membranes.   6 *) Valve block according to any one   Claims 1 to 5, characterized in that the   ramifications (5) are made in the form of a cross.   7 ') Valve block according to any one of   Claims 1 to 6, characterized in that   pressure equalizing valve is disposed therein, in each adsorber gas line (1), valve connected to the pressure equalizing valves of each of the other adsorber gas lines (1). 8 ') Valve block according to any one of   Claims 1 to 7, characterized in that in   three adsorber pressure swing adsorption plants, adsorber gas lines   (1) and the production gas lines (4) are   terchangeables between them in their provision on the block of valves.   9e) Valve block according to claim   1, characterized in that it consists of   Suitable for aluminum or thermoplastic material.   In the latter case, such a block of valves may be   manufactured by injection molding.