JPS5914403B2 - Method of combined operation of sulfur oxide receiving plant and sulfur dioxide conversion plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The invention combines a plant for the conversion of sulfur dioxide with a plant in which sulfur oxides are received from a gas or gas mixture onto a solid acceptor and subsequently released again by regeneration of the acceptor. and how to operate it.

Sulfur oxides can be removed from gases containing them, such as boiler flue gas, by reception on a solid acceptor.

Loaded acceptors continue to be regenerated.

The sulfur dioxide content of the regenerated off-gas leaving the plant where the sulfur oxides are received varies from zero or substantially zero initially to an intermediate maximum value during regeneration at the end of regeneration.

In the case of combined operation of a plant for the conversion of sulfur dioxide and the aforementioned plant, the varying sulfur dioxide concentration in the regenerated off-gas becomes the main control engineering difficulty for the former plant.

For example, in plants for the recovery of elemental sulfur, generally of the Claus type, sulfur is extracted from sulfur dioxide and hydrogen sulfide at least partially in the presence of a catalyst according to the reaction 2H2SSO2→S1H20. It is formed.

In order to ensure that the reaction proceeds as completely as possible and thus to keep the concentration of hydrogen sulfide and/or sulfur dioxide in the off-gas of said second plant as low as possible, hydrogen sulfide and sulfur dioxide are required stoichiometrically. It is very important that the amount of water is supplied at the desired ratio.

If the sulfur dioxide concentration changes as described above, the hydrogen sulfide concentration must change accordingly, or if hydrogen sulfide is supplied at a constant rate, sulfur dioxide must be additionally supplied. First, the feed rate depends on the sulfur dioxide concentration in the resulting regenerated off-gas.

The plant for the conversion of sulfur dioxide may consist of a sulfuric acid plant.

In such plants, sulfur dioxide is first catalytically converted to sulfur trioxide, and the sulfur trioxide is subsequently absorbed into a diluted or more concentrated sulfuric acid solution, in which case It is also highly undesirable for the starting gas stream to have an altered sulfur dioxide content.

The invention provides the possibility of operating a plant in which sulfur oxides are received in combination with a plant for the conversion of sulfur dioxide by linearization of the highly variable sulfur dioxide content in the regenerated off-gas. supply.

The invention is a method for operating a plant in which sulfur oxides are received from a gas or gas mixture on a solid acceptor and subsequently released again by regeneration of the acceptor, in combination with a plant for the conversion of sulfur dioxide, Said method, wherein the former plant comprises at least two reactors used alternately for the reception of sulfur oxides and subsequent regeneration of the loaded acceptor, resulting in a regenerated off-gas having a varying sulfur dioxide content. In order to obtain a constant or substantially constant sulfur dioxide flow to the plant for sulfur dioxide conversion and to maintain continuous compression of the sulfur dioxide-containing gas stream, the regenerated off-gas is cooled and condensed. After water removal, it is compressed in a compressor and stored under pressure in a gas holder, from which sulfur dioxide is supplied to the second plant, and the compressor is also connected to the gas holder on its suction side. and, on the other hand, whenever the sulfur dioxide content in the regenerated off-gas is zero or substantially zero, the regenerated off-gas is fed without compression to the combustion plant after said cooling and condensate removal, and the regenerated off-gas is fed to the combustion plant. sulfur dioxide is drawn from the gas holder by the compressor for compression.

The cooled regenerated off-gas is preferably compressed to a pressure of 1 to 10 atmospheres, more preferably 2 to 6 atmospheres.

In the following, a plant in which sulfur oxides are received from a gas or a gas mixture onto solid acceptors and subsequently released again by regeneration of these acceptors is
For simplicity, it will be referred to as the receiving plant or first plant.

In general, such a plant will include at least two actuators (or treatment spaces) used alternately for receiving, although it is possible that three or more actuators or treatment spaces may be used. It is.

Such plants can be used to remove sulfur oxides from flue gases so that the flue gases can be freely released into the atmosphere without causing air pollution.

The acceptors used within the receiving plant generally include metals and/or metal compounds supported on a support.

Particularly suitable acceptors of this type include copper oxides supported on an alumina support.

The plant for the conversion of sulfur dioxide will be referred to as the second plant for simplicity.

From the foregoing it will be appreciated that the second plant may be a sulfuric acid plant or a sulfur recovery plant.

It will be understood from the following description that the sulfur recovery plant is a variation of a conventional Claus plant with respect to the non-contact part of such a conventional plant for the recovery of elemental sulfur.

A plant for supplying a constant or substantially constant sulfur dioxide gas stream will be referred to as a homogenization plant for simplicity.

The regeneration off-gas leaving the receiving plant during regeneration is 325
~500°C, and the gas initially has a temperature of 100°C.
Desirably, the temperature is lower than 0.degree.

Preferably, the cooling is carried out in two stages, with the cooling in the first stage being carried out to a temperature just above the dew point at the applied pressure to produce a low pressure flow, and followed by the second stage? Cooling is then carried out to a temperature well below the dew point to form condensate water.

The latter stage consists of a column (co I
umu).

For example, the regenerated off-gas is cooled to a temperature of 35-70°C.

Steam stripping (str
(ipping), the condensate formed can be freed of dissolved sulfur dioxide, which can be recycled to the regenerated offgas.

If a hydrogen-containing regeneration gas is used, water vapor is formed through regeneration of the loaded acceptor.

In addition, water vapor is also preferably added to the regeneration gas.

The cooling of the regenerated off-gas therefore serves the additional purpose of removing all of the added and formed water vapor and further increasing the sulfur dioxide concentration of the regenerated off-gas.

After cooling, the regenerated off-gas may be compressed using any suitable compressor.

Preferably, the regenerated off-gas is recooled after compression.

The cooling may be carried out directly or indirectly, but most suitably the compressed off-gas is cooled in a manner prior to its compression, i.e. by countercurrent contact with water or an aqueous solution. .

As a result of the nature of the processing carried out within the receiving plant,
At some point during the process, the sulfur dioxide concentration in the off-gas is zero or substantially zero, and in such cases there is no water vapor mixed or unmixed with the gaseous components of the reducing gas used as regeneration gas. , or a mixture of steam and reducing gas is fed to the homogenization plant.

In order to be able to keep the compressor in operation in these cases, in a preferred embodiment of the process of the invention, the regenerated off-gas is compressed after cooling by a compressor, which also has suction side trowel sulfur dioxide. sulfur dioxide is withdrawn from the holder at a time when the sulfur dioxide content in the regenerated off-gas is zero or substantially zero.

Thus, during the period when the regenerated off-gas contains a high concentration of reducing gas and is free of sulfur dioxide, the off-gas, after condensation of the water vapor present in the off-gas as described above, is transferred to a suitable combustion plant, e.g. It is possible to feed the furnace of the boiler that generates it.

Another suitable combustion plant for the special regenerated off-gas is a second plant combustion furnace.

The embodiment described above makes it possible to select a smaller size of the gas holder, since the volume of gas to be stored is smaller.

Ensures that the valve in the line is opened and/or at the desired time
or the necessary control device should be present to enable it to be closed.

There is no need to discuss this point further as it will be well understood by those skilled in the art.

switching the valve group
For example, the signal to
conductivity), which increases rapidly in the presence of hydrogen, may be derived by measuring its conductivity.

The embodiment described is such that the contents of the gas holder are thoroughly mixed so that no concentration differences occur within the gas holder, and a gas stream having a substantially constant sulfur dioxide content is provided for subsequent treatment. It also has the advantage of being removed from the gas holder for the stage.

As a result of the foregoing, in the presence of suitable controls to provide continuous mixing, the compressor can remove sulfur dioxide from the gas holder even at times when the sulfur dioxide content in the regenerated off-gas is non-zero or substantially non-zero. Sulfur can be extracted.

For that purpose, a small partial stream of about 1 to 10% of the total volume of gas to be compressed is usually used.
It would be sufficient for the compressor to draw the ream).

The sulfur dioxide concentration in the gas stream leaving the gas holder towards the second plant ranges from 75 to 95% by volume, depending on the receiving plant and the regeneration gas used.

The gas holder to which the compressed sulfur dioxide-containing gas is supplied may have a constant volume or a constant pressure may be maintained therein.

In the former case, the pressure in the gas holder will change and will drop when the sulfur dioxide content in the regenerated off-gas is zero or virtually zero, while the sulfur dioxide from the gas holder is A constant supply is provided to two plants.

If a pressure of about 4 ky/ffl is thus used, the pressure in the gas holder will vary, for example, from 2.5 to 4 kg/i.

The degree to which the pressure in the gas holder drops will depend in common on the length of time that sulfur dioxide is not supplied to the homogenization plant and on the size of the gas holder.

In the latter case, the pressure therein is kept constant by changing the volume of the gas holder, ie by changing the liquid level in the gas holder.

A suitable liquid for this application is water.

However, since the latter method requires additional equipment, a method using a gas holder having a certain volume is preferred.

Sulfur dioxide stored in the gas holder. The gas holder can now be drawn off for the operation of a second plant, either for a sulfuric acid plant or a Claus plant, or for other processes where a constant sulfur dioxide stream is required. It may be a plant of

Since the production of sulfuric acid is always based on sulfur dioxide, the production of sulfuric acid will not need further discussion.

If the second plant is a Claus plant, the Claus plant should be adapted or, if necessary, modified, since hydrogen sulfide or a gas containing hydrogen sulfide is normally used as feedstock for the Claus plant. .

The invention also relates to an apparatus in which a sulfur oxide-containing gas is purified of sulfur oxides and the separated sulfur oxides are further converted to sulfur or elemental sulfur. including plants for;
Said plant comprises at least two reactors - a plant for supplying a constant sulfur dioxide gas stream and a plant for converting sulfur dioxide, wherein the plant for supplying a constant sulfur dioxide gas stream comprises: a compressor, a cooler and a gas holder, the suction inlet of the compressor being connected directly or indirectly with an outlet for regenerated off-gas containing sulfur dioxide from the plant for receiving the sulfur oxides; The outlet of the compressor is connected to the inlet of the cooler, while the inlet of the gas holder is connected to the outlet of the cooler, and the gas outlet of the gas holder is directly connected to the inlet of the plant for conversion of sulfur dioxide. It relates to a device characterized in that it is connected to or indirectly connected to.

The second outlet of the gas holder is connected to the suction inlet of the compressor.

The method of the invention will be further described in connection with the accompanying Figures 1-4 and examples.

The flowchart shown in FIG. 1 is divided into three parts, A containing the receiving plant, B containing the equalization plant, and C containing the second plant, in this case the Claus plant.

The system is completely closed with respect to sulfur compounds;
The gas discharged through the chimney therefore does not cause air pollution.

All of the sulfur compounds supplied through line 1 in the form of sulfur dioxide and through line 57 in the form of hydrogen sulfide are converted to elemental sulfur, which is removed from the system.

In the embodiment shown in FIG. 2, part B is the pressure vessel 1
9 is shown in a modified form.

In the figures, all identical components are indicated by identical numbers.

Although not shown in Figures 2 and 1, the necessary control equipment should be installed to close and/or open the valves as necessary depending on the sulfur dioxide content in the regenerated off-gas. will be understood by those skilled in the art.

The embodiment of the invention shown in FIG. 3 is particularly suitable for cases where there is no independent source of hydrogen sulfide for operation of a Claus plant.

The reformed part C consists of C1 and C2, the first part containing the partial reduction plant and the second part containing the Claus plant.

In the illustrated case, the entire sulfur dioxide gas stream originating from gas holder 19 passes through a pipe reactor 63, which is maintained at the desired reduction temperature by steam and/or boiling water or other suitable coolant. dripping

In the embodiment shown in FIG. 4, portion C1 includes a burner chamber 71 to which a non-catalytic reaction chamber 72 is connected.

A sulfur dioxide gas stream is fed to a burner within the burner chamber while a suitable hydrocarbon such as butane is mixed with the sulfur dioxide.

Example 1 Flue gas with a SO□ content of 0.25% by volume was
The process was carried out in an apparatus comprising a receiving plant as shown in Figure Parts A and B and a plant for supplying a constant sulfur dioxide stream.

The resulting sulfur dioxide was subsequently converted with sulfur in a second plant as shown in No. 4M.

Flue gas having a temperature of about 390° C. is fed through line 1 at substantially atmospheric pressure and mixed in a volume ratio of 65:1 with off-gas from combustion furnace 55 which is recirculated through line 56. did.

The temperature of the off-gas is about 490°C and the S02 content is 18
It was 3% by volume.

At the same time, approximately 5% of the flue gas treated in reactor 2 or 2' was recycled through line 7 to the suction side of fan 6.

The gas has a temperature of 452°C and about 0.026% by volume S
The remainder of the treated flue gas having a 0.02 content is introduced into the air preheater 4 of the boiler and then the flue gas is discharged and ventilated via line 5 to the stack after being loaded into the acceptor. was regenerated in reactor 2 or 2' as shown for reactor 2'.

This was done by introducing regeneration gas containing hydrogen and methane and diluted with water vapor through line 9 via line 8 at a pressure of 15 atmospheres and a temperature of 330°C.

The regeneration produces an average amount of off-gas of 2950 ONrr with a maximum SO□ content of 8.25% by volume and a temperature of 425°C.
l/h was obtained.

The regenerated off-gas thus obtained was passed through line 10 via cooler 11 to column 12, where it was cooled to a temperature of about 40°C.

The cold regenerated off-gas thus obtained is passed through line 13 via valve 24 and line 25 to combustion furnace 55 during periods when it predominantly contains hydrogen and methane, and during other periods. was passed through a pipe 13 to a valve 14 and a pipe 15 to a compressor 16.

The former period is about 30% of the total regeneration and switching time.
Met.

The amount of gas passed through compressor 16 to column 17 was 3500 Nrrt/h and had an SO2 content varying from 15% to 75%.

The lowest SOA degree is substantially sulfur dioxide-free line 1
The measurements are taken at the time when gas is being supplied through 5, which is the case just before and after the switching of valves 14 and 24.

The highest concentration, on the other hand, was measured at the midpoint of the period during which the gas was being supplied through line 15.

During the latter period, approximately 5% of the total gas flow was supplied to the compressor via line 22 and valve 23.

During the period when valve 14 was closed, the entire volume was recirculated from gas holder 19 via line 22.

The compressor inlet pressure was 1.15 atm, the outlet pressure was 4.0 atm, and the inlet temperature was about 40°C and the outlet temperature was about 145°C.

In order to keep the volume of the gas holder 19 as small as possible, the off-gas from the compressor is
℃ and subsequently passed through line 18 to a gas holder.

The gas flow via line 18 to gas holder 19 is 330
ONrn'/h, the amount of gas sent to the burner chamber 71 at a constant pressure of 2.2 atm via the valve 21 and the pipe 20 is 2200 Nm/h, and 67% to 72%.
The SO2 concentration varied at .

The pressure inside the gas holder is between 2.6 atm and 3.9 atm during operation.
It changed with atmospheric pressure.

A pressure of 3.9 atmospheres was reached when valve 14Z was closed, while a pressure of 2.6 atmospheres was reached when valve 14 was reopened.

Since the water vapor is condensed in column 12 and in column 17, the amount of water pumped by pump 27 from column 12 via line 26, which has a temperature of approximately 80°C, is The amount of water used for cooling purposes after cooling to about 35° C. was 21.6 m/h more.

The supercharged hot water contains 0.85% by weight of sulfur dioxide and is supplied via line 35, valve 36 and line 37 to stripper column 38, where the sulfur dioxide is converted into low pressure steam via line 40. It was released by injection of approximately 750 kg/h.

The released SO2 was recycled to column 12 via line 39, and the sulfur dioxide-free water was removed via line 41, pump 42, valve 43 and heat exchanger 44.

The bulk of the coolant was supplied via line 28 to a heat exchanger 29 where it was cooled against water.

After cooling, a portion of the coolant was supplied to column 12 via lines 30 and 31.

Another portion of coolant was supplied to column 17 via line 32, valve 33 and line 34 to cool the hot and compressed sulfur dioxide-containing gas as described above.

After cooling, the coolant flows through line 45, valve 46 and line 5.
0 and then recirculated to column 12.

The coolant introduced into or condensing in pressure vessel 19 was recycled to column 12 via line 48, valve 49 and line 50.

Via line 70, 750 Nm'/h of methane are added to the sulfur dioxide-rich gas from the gas holder, after which the gas mixture together with the required amount of air supplied through line 77 in burner chamber 71. After baking, the temperature in the burner is 1290° C., and the off-gas from the reaction chamber 72 contains 4.2% by volume of carbon disulfide, 3.6% by volume of sulfur dioxide, and 1.8% by volume of hydrogen plus oxidation. In addition to carbon, especially nitrogen, it contained carbon dioxide and elemental sulfur.

55 of the elemental sulfur formed in the combustion gases from the reaction chamber 72 cooled by water supplied through line 73.
% was removed as liquid sulfur through line 75 and at the same time 9/h of water vapor was produced which was removed through line 74.

The off-gas passes through line 76 to two contact Claus zones 5.
8' and 58", the first zone of which contains a catalyst for the reduction of sulfur dioxide in order to achieve substantially complete conversion of the hydrogen and carbon monoxide formed in the burner chamber 71. Filled.

The second catalytic zone contained a conventional Clauss catalyst.

In these zones, 80% of the sulfur content still present in the off-gas is converted to elemental sulfur and passed through line 59.
removed through.

The off-gas from contacting zones 58' and 5B'' still contains carbon disulfide, sulfur dioxide and elemental sulfur and is passed via line 54 to a combustion furnace 55 where it is treated with 130 ONrn'/h of fuel gas and excess 500℃ with air
The mixture was burned at a temperature of 100 ml, thus converting all remaining sulfur components to sulfur dioxide.

Excess air was supplied through line 51, fan 52 and line 53.

Combustion gases from furnace 55 were recycled to the receiving plant through line 56.

Excess reducing gas not required for regeneration may also be supplied to the combustion furnace via line 60 and used as fuel for combustion.

Additional fuel may therefore also be supplied via line 61.

Example 2 Flue gas having a SO□ content of 0.14% by volume was
Processing was carried out in an apparatus comprising a receiving plant and a homogenizing plant as shown in Figure Parts A and B.

The sulfur dioxide produced was subsequently converted to sulfur in a plant as shown in FIG.

A flue gas having a temperature of about 400° C. is fed through line 1 at substantially atmospheric pressure and with off-gas from the combustion furnace 55 recirculated through line 56 about 100° C.
They were mixed at a volume ratio of 1:1.

The temperature of the off-gas is about 500°C and the S02 content is 0.
It was 92% by volume.

At the same time, approximately 5% of the flue gas treated in reactor 2 or 2' was recycled through line 7 to the suction side of fan 6.

The gas has a temperature of 420°C and about 0.015% by volume S
It had an O2 content.

After being loaded, the acceptor was regenerated in reactor 2 or 2 as shown for reactor 2'.

This means that regeneration gas diluted with water vapor and containing hydrogen, carbon dioxide and traces of methane, carbon monoxide and nitrogen at a pressure of 1.5 atmospheres and a temperature of 300°C.
This was done by introducing it through line 8.

The regeneration produces an average amount of off-gas of 9700 Nrn with a maximum SO□ content of 8.35% by volume and a temperature of 420°C.
'/h was obtained.

The regenerated off-gas thus obtained is passed through line 10 and cooler 11 to column 12, where it is further heated to 40°C.
cooled to.

The cold regenerated off-gas thus obtained is passed through valve 24 and line 25 to combustion furnace 55 during periods when it primarily contains hydrogen and carbon dioxide, and during other periods through valve 14 and line 25. It was passed through the compressor 16 via the route 15.

The former period accounts for approximately 37.5% of the total regeneration and switching time.
It was 5%.

The amount of gas passed to column 17 via compressor 16 was 161 ON/h and had an 802 content varying from 10% to 55%.

The lowest concentration is measured when gas is being supplied through line 15 substantially free of sulfur dioxide, which is the case just before or after switching valves 14 and 24, while the highest concentration is when gas is being supplied through line 15 substantially free of sulfur dioxide. It was reached at the midpoint of the time being fed via line 15.

During the latter period, approximately 5% of the total gas flow was supplied to the compressor via line 22 and control valve 23.

During the period when valve 14 was closed, the entire volume was recirculated from gas holder 19 via line 22.

The inlet pressure of the compressor is 1.15 atm, and the outlet pressure is 4. θ atmospheric pressure, inlet temperature is about 40℃ and outlet temperature is about 1
The temperature was 50°C.

Off gas from the compressor is 40℃ in column 17
and subsequently passed via line 18 into the bottom compartment 19a of the gas holder 19.

The gas flow to the gas holder via line 18 is 1540
Nm/h and the amount of gas passed for catalytic reduction of sulfur dioxide via valve 21 and line 20 to reactor 63 at 3.5 atm is 91 ONrrt/h and at 43-47% It had a varying degree of 804 degrees.

In order to keep the pressure in the bottom of the gas holder constant during the period when the valve 14 is closed, water is supplied from the upper compartment 19b via a conduit 81, a valve 82 and a conduit 83 which exit below the liquid level 80. Water is introduced into the lower compartment at a rate of 2587 TVh, and during the period when valve 14 is open, water is introduced from the lower compartment through line 48, pump 84, line 8
5, 15 to the upper compartment via valve 86 and conduit 8γ
It was pumped at a speed of 8 m/h.

Since water vapor condenses in column 12 and also in column 17, excess cooling water saturated with SO2 was stripped and removed as described in Example 1.

Coolant introduced into the lower compartment or condensed therein to increase the volume of water circulating between the upper and lower compartments was recirculated to column 12 via valve 49 and line 50. .

130 ONrrr”/h of reducing gas having a temperature of 300° C. and containing mainly hydrogen and carbon monoxide as active components
was added via line 62 to the gas coming from gas holder 19 and subsequently passed to pipe reactor 63.

The gas mixture is 50 O gas per liter of catalyst per hour.
passed through the reactor at a space velocity of Nl.

Meanwhile, two-thirds of the sulfur dioxide present is converted to hydrogen sulfide, 82% of which is further reacted with the sulfur dioxide still present, which causes the gas mixture to pass through line 64 to the Clauss for further conversion. It was removed in liquid form via line 5g before being introduced into plant 58.

The catalyst used in reactor 63 was sulfurized Co
/Mo/A I 20 s catalyst.

During the reduction of sulfur dioxide, a large amount of heat is generated, which takes into account the boiler feed water, which is supplied via line 68 and is preheated in vessel 66 before being introduced via line 67 into vessel 63. It is not used for converting into high pressure steam of kg/ffl.

The water vapor was removed from vessel 63 via steam line 65 and separated from the water trapped within vessel 66.

The amount of dry steam generated and leaving vessel 66 via line 69 was 13,701 #/h.

88% of the sulfur component still present in the gas leaving the reduction reactor, which contained inter alia 2.6% by volume and 8021.3% by volume of H2S, was further converted to elemental sulfur in the Claus plant 58.

Offgases from the Claus plant containing hydrogen sulfide, sulfur dioxide, and elemental sulfur, among others, were combusted with excess air and fuel gas as described in Example 1 and recycled to the receiving plant.

Example 3 Flue gas having an SO□ content of 0.135% by volume was
It was processed in an apparatus comprising a receiving plant and a homogenization plant as shown in parts A and B of the figure and fed to a sulfuric acid plant as a second plant.

Flue gas having a temperature of about 400° C. is fed through line 1 and mixed with off-gas from combustion furnace 55 in a volume ratio of about 60=1, the temperature of which is about 500° C. and S02 The content was 0.83%.

After loading, the acceptor was regenerated in reactor 2 or 2 as shown for reactor 2'.

This is obtained by partial combustion of naphtha diluted with steam and with air and inter alia (H2+C
0) 20%, (N2+C02) 41% and H2O38
% by introducing regeneration gas through line 8 at a pressure of 1.5 atmospheres and a temperature of 400°C.

The regeneration results in an average amount of off-gas of 980 ONm'/ with a maximum S02 content of 8.3% by volume and a temperature of 420°C.
h occurred.

The off-gas was treated in a homogenization plant as in Example 1, but the amount of gas was different.

The amount of gas passed through the compressor 16 and column 17 to the gas holder 19 is 49
60 Nm”/h and its SO2 content is 5%
It varied between ~18%.

The amount of gas passed from the gas holder through the pipe 20 is 3
125Nrn'/h, and its SO2 content is 1
It varied between 3.2% and 14.3%.

The gas was fed to a conventional plant for the production of sulfuric acid via catalytic oxidation of sulfur dioxide to sulfur trioxide and absorption into a sulfuric acid solution.

[Brief explanation of the drawing]

FIG. 1 shows a receiving plant and a second plant operated in combination such that a gas stream having a varying sulfur dioxide content is converted by a homogenizing plant into a gas stream having a constant sulfur dioxide content. Show a flowchart. FIG. 2 shows a variation of the flowchart shown in FIG. 1 for a homogenization plant. FIG. 3 shows a modification of the flowchart shown in FIG. 1 for a second plant. FIG. 4 shows a modification of the flowchart shown in FIG. 1 for a second plant. 2, 2'-...reactor, 11...
Cooler, 12...Column, 16...
Compressor, 17...Column, 19...
... Gas holder, 38 ... Stripper column, 55 ... Combustion furnace, 58 ... Claus plant, 63 ... Pipe reactor, 1
1... Burner chamber, 72... Catalyst reaction chamber.

Claims (1)

[Claims] 1. A process in which a plant for the conversion of sulfur dioxide is operated in combination with a plant for the conversion of sulfur dioxide, in which sulfur oxides are accepted from a gas or gas mixture onto a solid acceptor and subsequently released again by regeneration of said acceptor, the former being In said method, the plant comprises at least two reactors used alternately for the reception of sulfur oxides and subsequent regeneration of the loaded acceptor to produce a regenerated off-gas having a varying sulfur dioxide content, In order to obtain a constant or substantially constant dioxide value yellow stream to the plant for the conversion of sulfur dioxide and to maintain continuous compression of the sulfur dioxide-containing gas stream,
After cooling and removal of condensate, the regenerated off-gas is compressed in a compressor and stored under pressure in a gas holder, from which sulfur dioxide is supplied to the second plant, and sulfur dioxide is supplied to the second plant in the compressor or on its suction side. connected to a gas holder, while the regenerated off-gas is fed without compression to the combustion plant after said cooling and condensate removal, whenever the sulfur dioxide content in the regenerated off-gas is zero or substantially zero; A method characterized in that sulfur dioxide is drawn from the gas holder by the compressor for compression when the sulfur dioxide is supplied to a combustion plant.