JPS5932575Y2 - Sulfur dioxide reduction device coupled with Claus reactor - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a sulfur dioxide reduction device installed upstream of a Claus reactor to reduce a process gas containing sulfur compounds with a coal-based reducing agent.

In flue gas desulfurization equipment that recovers sulfur by reducing high concentration sulfur oxides with a coal-based reducing agent, in order to increase the sulfur recovery rate, the Claus reaction (2H2S+502= 2H20+3S) may be installed.

At this time, the Claus reaction should be performed ideally and 2S To tighten, set the gas ratio value to 202 This is desirable.

However, with conventional technology, it has been determined that it is difficult to maintain the gas ratio value at 2 in a reduction device using coal or coal-based carbon, so a slight excess of H2 is produced in the reduction device.
The gas ratio was adjusted to 2 by bypassing some of the raw gas, but since the amount of bypass was not very large, the pipes were clogged with dust, causing control problems. However, there were drawbacks such as reduced performance and difficulty in adjusting the flow rate.

In addition, the gas ratio value described above changes depending on the operating method of the reduction equipment (i.e., even if the operating temperature, amount of water vapor, or amount of transferred reducing agent is adjusted, etc.), but the response is very slow, so it is not practical. has not yet been reached.

The present invention provides a plurality of gas outlet ports at appropriate intervals in the SO2 reducer, and when extracting gas from these gas outlet ports, the gas ratio of the 2S installed before or after the Claus reactor is adjusted. Based on the signal from the gas detector that detects the O2 value, the position of the gas outlet is selected so that the gas ratio of the gas flowing into the Claus reactor becomes 2. Examples will be described with reference to the drawings.

In the figure, 1 is a vertical SO2 reducer, and 2 is a Claus reactor.

The reducer 1 has a reducing agent inlet 3 at the top, a used reducing agent outlet 4 at the bottom, and a process gas inlet 5 near the bottom. First gas outlet ports 6 are arranged above the port 5 at appropriate intervals from the bottom to the top, that is, in the flow direction of the processing gas.
, a second gas outlet 1, a third gas outlet 8, . . . are provided.

Also, a first duct 9 connected to the first gas outlet 6
A first on-off valve 12 is provided in the middle of the second duct 10, and a second on-off valve 13 is provided in the middle of the second duct 10 connected to the second gas extraction lower.
a third duct 1 connected to the third gas outlet 8;
A third on-off valve 14 is provided in the middle of the valve 1.

Reference numeral 15 denotes a merging duct in which the ducts 9 to 11 are joined together, which is connected to the Claus reactor 2, and a gas analyzer for detecting the gas ratio of 1'8 of the gas flowing through the merging duct 15. A gas detector 16 is provided, and a detected electric signal 19 from this gas detector 16 is compared with a setting electric signal 20 that sets the value of the gas ratio to 2, and the deviation is transmitted as a deviation electric signal 21. comparator 11 and this comparator 1T
Control electric signals 22 to 24 are sent to the on-off valves 12 to 14 so that the deviation is eliminated by receiving the deviation electric signal 21 from the
A valve opening/closing control device 18 is provided which controls the opening degrees of the opening/closing valves 12 to 14 and selects the gas outlet ports 6 to 8.

In addition, 25 is a reducing agent supply duct, 26 is a processing gas duct, 2T is a used reducing agent duct, and 28 is a sulfur recovery duct.

In the sulfur dioxide reduction device configured as shown in the figure, first, the reducing agent of coal or coal-based carbon is introduced into the inlet 3.
The used reducing agent is supplied into the SO2 reducer 1 and descends within the reducer 1 as shown by the dotted arrow, and the used reducing agent is discharged from the discharge port 4.

On the other hand, a processing gas containing a high concentration of sulfur compounds is introduced into the reducer 1 from the inlet 5 and rises inside the reducer 1 as shown by the solid arrow.

The process gas thus comes into countercurrent contact with the reducing agent in the reductor 1 and reacts with the reducing agent to generate sulfur or hydrogen sulfide.

Then, as will be described later, this gas is guided to the Claus reactor 2 through any one of the first duct 9 to the third duct 11 depending on the amount of hydrogen sulfide generated.

That is, the composition distribution of the processing gas in the reducer 1 is as shown in Table 1.

Therefore, the gases provided in the vertical direction of the SO□ reducer 1 are arranged so that the gas ratio O2 of H and S of the gas flowing into the Claus reactor 2 disposed after the SO□ reducer 1 is 2. Any one of the extraction ports 6 to 8 may be selected.

That is, the on-off valves 12 to 14 may be operated.

For example, if the value of the gas ratio in the middle part of the reducer 1 is 2, the first on-off valve 12 and the third on-off valve 14 are closed, and the second on-off valve 12 and the third on-off valve 14 are closed.
It is sufficient to open only the on-off valve 13 and supply the middle gas in the reducer 1 to the Claus reactor 2 from the second gas extraction lower.

However, when the value of the gas ratio is larger than 2, that is, when a large amount of H2S is generated, the second on-off valve 13 and the third
The on-off valve 14 is closed, the first on-off valve 12 is opened, and the gas in the lower part of the reducer 1 is supplied to the Claus reactor 2 from the first gas outlet 6, and conversely, when the value of the gas ratio is 2. If the amount is less, that is, if the generation of H2S is small, the first on-off valve 12 and the second on-off valve 13 are closed, the third on-off valve 14 is opened, and the inside of the reducer 1 is discharged from the third gas outlet 8. What is necessary is to supply the upper gas to the Claus reactor 2.

Of course, if necessary, each of the valves 12 to 14 may not only be fully opened or fully closed, but also adjusted to an appropriate opening degree.

The opening/closing control of each of the valves 12 to 14 is performed by the comparator 17 receiving the aforementioned detection electric signal 19 from the gas detector 16 and comparing it with the setting electric signal 20. This is done by sending a deviation electrical signal 21 to the valves 12 to 14, and the control device 18 correspondingly sending predetermined control electrical signals 22 to 24 to the valves 12 to 14.

Although a sulfur condenser is generally installed after the reducer 1 in the flow, its illustration is omitted in this embodiment.

In addition, the gas that generated sulfur in Claus reactor 2 is transferred to duct 2.
8 to a sulfur condenser (not shown).

As mentioned above, the present invention is installed upstream of the Claus reactor to introduce the coal-based reducing agent from the top and to reduce the SO2
In a sulfur dioxide reduction device that introduces a processing gas containing from the lower part and brings the reducing agent and the processing gas into countercurrent contact to generate a reducing gas, Since the SO2 reducer is equipped with a plurality of gas outlet ports, when extracting gas from the gas outlet ports, it is possible to simply use the fact that the composition distribution of the processing gas differs depending on the position in the reducer. By selecting the gas outlet, the O2 value of the waste ratio of the gas flowing into the gas reactor can be adjusted to 2, and the structure is simple and the operation is easy. , and an on-off valve provided for each duct connecting each of the gas outlet ports and the Claus reactor; A gas detector detects the value, and a detection signal from this gas detector is compared with a setting signal that sets the gas ratio value of the gas flowing into the Claus reactor to 2, and the deviation is transmitted as a deviation signal. and a valve opening/closing control device that receives a deviation signal from the comparator and controls the opening degree of the opening/closing valve so as to eliminate the deviation and selects the gas outlet. Even if the internal conditions of the reducer change, the operating conditions remain the same: selecting the gas outlet, and the response speed is fast.The effects of the present invention are extremely It's a dog.

[Brief explanation of the drawing]

The figure is an elevational view showing an outline of an embodiment of the present invention. 1... SO2 reducer, 2... Claus reactor, 3... Reducing agent inlet, 4...
Used reducing agent outlet, 5...processing gas inlet, 6. γ, 8...Gas outlet, 9, 10, 1
1...Duct, 12゜13.14...
Opening/closing valve, 15... Merging duct, 16...
・Gas detector, 1γ... Comparator, 18...
...Valve opening/closing control device.

Claims (1)

[Claims for Utility Model Registration] The reactor is installed upstream of the Claus reactor, and a coal-based reducing agent is introduced from the top, and a processing gas containing SO2 is introduced from the bottom, so that the reducing agent and the processing gas are brought into countercurrent contact. A sulfur dioxide reduction device that generates reducing gas, comprising an SO2 reducer having a plurality of gas outlet ports provided at appropriate intervals in the flow direction of the processing gas, and each of these gas outlet ports. and a gas detector provided either before or after the Claus reactor to detect the value of the waste ratio of H2S and □. , O2 A comparator that compares the detection signal from this gas detector with a setting signal that sets the value of the gas ratio of the gas flowing into the Claus reactor to 2, and transmits the deviation as a deviation signal; and a valve opening/closing control device that receives a deviation signal from a comparator and selects the gas outlet by controlling the opening degree of the opening/closing valve so that the deviation disappears. Sulfur dioxide reduction equipment.