CN216669825U

CN216669825U - Device for controlling oxidation process of wet desulphurization slurry in real time

Info

Publication number: CN216669825U
Application number: CN202122073275.6U
Authority: CN
Inventors: 房孝维; 何育东; 李兴华; 陶明; 何仰朋; 孟令海; 余昭; 吴晓龙; 李楠; 宦宣州; 王韶晖
Original assignee: Xian Thermal Power Research Institute Co Ltd
Current assignee: Xian Thermal Power Research Institute Co Ltd
Priority date: 2021-08-30
Filing date: 2021-08-30
Publication date: 2022-06-03
Anticipated expiration: 2031-08-30

Abstract

The utility model discloses a device for controlling the oxidation process of wet desulphurization slurry in real time, which comprises a control system, a hydrocyclone, a sulfite test box, a filtrate tank and a plurality of oxidation fans, wherein a sampling port of a gypsum slurry main pipe is communicated with an inlet of the hydrocyclone, an outlet at the top of the hydrocyclone is communicated with an inlet of the sulfite test box, an inlet of the filtrate tank at an outlet of the sulfite test box is communicated with an inlet of the sulfite test box, an output end of the sulfite test box is connected with an input end of the control system, and an output end of the control system is connected with control ends of the oxidation fans.

Description

Device for controlling oxidation process of wet desulphurization slurry in real time

Technical Field

The utility model belongs to the technical field of chemistry, and relates to a device for controlling the oxidation process of wet desulphurization slurry in real time.

Background

At present, the thermal power plant mainly adopts a limestone-gypsum wet desulphurization process to remove SO generated in the combustion process₂The sulfur (IV) containing substances in the slurry in the wet desulphurization process mainly comprise: sulfurous acid and corresponding acid salts and normal salts (e.g. H)₂SO₃、HSO₃ ^-、SO₃ ^2-、CaSO₃Etc.), all are +4 valent species. The oxidation degree of the slurry of the absorption tower in the wet desulphurization process is monitored in real time, the content of sulfur (IV) containing substances in the slurry is determined, the accurate adjustment of the oxidation air volume is facilitated, and the safe and energy-saving operation and automatic control of a desulphurization system are realized.

Evaluation of slurry oxidation process of absorption towerThe method of manual sampling-laboratory detection is adopted. Compared with the actual situation, the oxidation condition of the slurry tested by the method has larger delay, the sulfur (IV) containing substance is easy to oxidize, and the deviation between the laboratory detection result and the actual situation in the slurry is larger. The online monitoring mainly adopts an ORP (oxidation-reduction potential) method, and the oxidation-reduction potential (ORP) of a slurry system can be changed along with the progress of an oxidation-reduction reaction, so that the oxidation-reduction process of the slurry can be judged by the ORP method of the slurry, and the oxidation-reduction process can be used as a basis for adjusting the air quantity of an oxidation fan, so that the slurry is prevented from being under-oxidized or over-oxidized, and the quality of the gypsum is ensured. At present, the ORP method mostly only considers the influence of PH, but Ca is actually used²⁺(or SO)₄ ^2-) The concentration and the dissolved oxygen are related, and the corresponding relation between the obtained ORP value and the concentration of the sulfur (IV) containing substances is poor; in addition, the existing ORP method directly measures the slurry, and the slurry contains a large amount of solid matters carried by limestone, gypsum and flue gas, so that the scouring strength of the oxidation-reduction electrode is large, the service life of the electrode and the precision of a test result are influenced, and the control of the whole oxidation process is further influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome the defects of the prior art and provides a device for controlling the oxidation process of wet desulphurization slurry in real time, which can realize the real-time control of the oxidation process of the wet desulphurization slurry, simultaneously avoid the influence of solid scouring on the service life of an electrode and a detection result and has higher detection accuracy.

In order to achieve the aim, the device for controlling the oxidation process of the wet desulphurization slurry in real time comprises a control system, a hydrocyclone, a sulfite test box, a filtrate tank and a plurality of oxidation fans, wherein a sampling port of a gypsum slurry main pipe is communicated with an inlet of the hydrocyclone, an outlet at the top of the hydrocyclone is communicated with an inlet of the sulfite test box, an inlet of the filtrate tank at an outlet of the sulfite test box is communicated, an output end of the sulfite test box is connected with an input end of the control system, and an output end of the control system is connected with control ends of the oxidation fans.

The sampling port of the gypsum slurry main pipe is communicated with the inlet of the hydrocyclone through a pump.

The bottom outlet of the hydrocyclone is communicated with the inlet of the vacuum belt conveyor.

Feeding the slurry output by the gypsum slurry main pipe into a hydrocyclone for solid-liquid separation, wherein the separated supernatant enters a sulfite test box, the separated solid phase enters a vacuum belt conveyor, the sulfite content of the supernatant is measured through the sulfite test box and then is sent to a control system, the control system calculates the deviation between the sulfite content of the supernatant and the critical sulfite content, then each oxidation fan is controlled according to the deviation, so that the deviation between the sulfite content of the supernatant and the critical sulfite content is within a preset range, and after the deviation between the sulfite content of the supernatant and the critical sulfite content is within the preset range, the overflow slurry of the sulfite test box is fed into a filtrate tank.

The sulfite test box comprises a box body, and an oxidation-reduction electrode, a calcium ion online tester, a PH meter, an oxygen dissolving instrument and a thermometer which are arranged on the box body.

The box includes rectangular shape cuboid groove and is fixed in the foraminiferous apron of rectangular shape cuboid groove top opening part, and wherein, redox electrode, calcium ion on-line measuring appearance, PH meter, dissolved oxygen appearance and thermometer all insert in the through-hole on foraminiferous apron.

Also included is determining a critical sulfite content.

And the control system controls the number and the frequency of the oxidation fans according to the deviation.

The utility model has the following beneficial effects:

when the device for controlling the oxidation process of the wet desulphurization slurry in real time is in specific operation, the slurry output by the gypsum slurry main pipe is subjected to solid-liquid separation through the hydrocyclone, wherein the supernatant enters the sulfite test box, the influence of solid scouring on the service life of a motor and a detection result in the sulfite test box is avoided, and the detection precision is improved.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the cover plate according to the present invention;

FIG. 3 is a flow chart of the present invention.

Wherein, 1 is an oxidation fan, 2 is a control system, 3 is a sulfite test box, 4 is a gypsum slurry main pipe, 5 is a vacuum belt conveyor, 6 is a pump, 7 is a hydrocyclone, and 8 is a filtrate tank.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments, and are not intended to limit the scope of the present disclosure. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present disclosure. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

There is shown in the drawings a schematic block diagram of a disclosed embodiment in accordance with the utility model. The figures are not drawn to scale, wherein certain details are exaggerated and possibly omitted for clarity of presentation. The shapes of various regions, layers and their relative sizes and positional relationships shown in the drawings are merely exemplary, and deviations may occur in practice due to manufacturing tolerances or technical limitations, and a person skilled in the art may additionally design regions/layers having different shapes, sizes, relative positions, according to actual needs.

Referring to fig. 1 and 2, the device for controlling the oxidation process of the wet desulfurization slurry in real time comprises a control system 2, a hydrocyclone 7, a sulfite test box 3, a filtrate tank 8 and a plurality of oxidation fans 1, wherein a sampling port of a gypsum slurry main pipe 4 is communicated with an inlet of the hydrocyclone 7, an outlet at the top of the hydrocyclone 7 is communicated with an inlet of the sulfite test box 3, an outlet of the sulfite test box 3 is communicated with an inlet of the filtrate tank 8, an output end of the sulfite test box 3 is connected with an input end of the control system 2, and an output end of the control system 2 is connected with a control end of each oxidation fan 1.

Specifically, a sampling port of the gypsum slurry main pipe 4 is communicated with an inlet of a hydrocyclone 7 through a pump 6, and a bottom outlet of the hydrocyclone 7 is communicated with an inlet of a vacuum belt conveyor 5.

Referring to fig. 3, the specific working process of the present invention is as follows:

and feeding the slurry output by the gypsum slurry main pipe 4 into a hydrocyclone 7 for solid-liquid separation, wherein the separated supernatant enters a sulfite test box 3, the separated solid phase enters a vacuum belt conveyor 5, the sulfite content of the supernatant is measured through the sulfite test box 3 and then is sent to a control system 2, the control system 2 calculates the deviation between the sulfite content of the supernatant and the critical sulfite content, and then the working number and the frequency of the oxidation fan 1 are controlled according to the deviation. So that the deviation between the sulfite content of the supernatant and the critical sulfite content is within a preset range, and when the deviation between the sulfite content of the supernatant and the critical sulfite content is within the preset range, the overflow slurry of the sulfite test tank 3 is sent to the filtrate tank 8.

The sulfite test box 3 comprises a box body, and an oxidation-reduction electrode, a calcium ion online tester, a PH meter, an oxygen dissolving instrument and a thermometer which are arranged on the box body, and oxidation-reduction potential and Ca are respectively detected by the oxidation-reduction electrode, the calcium ion online tester, the PH meter, the oxygen dissolving instrument and the thermometer²⁺Concentration, H⁺Concentration, O₂The concentration and temperature signals are sent to a control system 2, and the control system 2 controls the concentration and temperature according to the oxidation-reduction potential and Ca²⁺Concentration, H⁺Concentration, O₂The concentration and temperature signal calculate the sulfite content of the supernatant, wherein the box body comprises a long-strip-shaped cuboid groove and a perforated cover plate fixed at the opening at the top of the long-strip-shaped cuboid groove, and the redox electrode, the calcium ion online tester, the PH meter, the dissolved oxygen meter and the thermometer are all inserted into a through hole in the perforated cover plate.

The utility model also comprises the following specific steps of determining the critical sulfite content:

1) obtaining a solid phase discharged from the bottom of the hydrocyclone 7, filtering to obtain a gypsum solid, flushing the gypsum solid by deionized water until the filtrate is neutral, and drying at 45 ℃ to obtain a gypsum sample;

2) determining the content of calcium sulfite in the gypsum sample by an iodometry method;

3) under different operating conditions, a comparison graph is drawn by taking the content of calcium sulfite in the gypsum sample as a horizontal coordinate and the content of sulfite overflowing from the hydrocyclone 7 as a vertical coordinate;

4) according to the requirement on the content of calcium sulfite in the gypsum, the corresponding content of sulfite in the overflow of the hydrocyclone 7 is obtained from the comparison graph, and the content of sulfite in the overflow of the hydrocyclone 7 is taken as the critical content of sulfite.

Example one

In this embodiment, the measured sulfite content is less than 95% of the critical sulfur (IV) containing material content, and the measured sulfite content is within the range of 95% to 100% of the critical sulfite content by reducing the frequency of the oxidation fan 1 or reducing the number of operating fans.

Example two

The sulfite content found in this example is greater than the critical sulfite content.

The measured sulfite content is in the interval of 95-100% of the critical sulfite content by increasing the frequency of the oxidation fan 1 or increasing the number of running fans.

EXAMPLE III

In this example, the measured sulfite content is 95% to 100% of the critical sulfite content.

The frequency or the number of running machines of the oxidation fan 1 is kept unchanged, so that the measured sulfite content is stabilized in the range of 95-100% of the critical sulfite content.

The applicant states that the present invention is illustrated by the above embodiments, but the present invention is not limited to the above embodiments, i.e. the present invention is not limited to the above embodiments. It will be apparent to those skilled in the art that any modifications of the present invention are within the scope and disclosure of the present invention.

Claims

1. The utility model provides a device of wet flue gas desulfurization thick liquid oxidation process real time control, a serial communication port, including control system (2), hydrocyclone (7), sulfite test box (3), filtrate tank (8) and a plurality of oxidation fan (1), wherein, the sample connection of gypsum thick liquid female pipe (4) is linked together with the entry of hydrocyclone (7), the top export of hydrocyclone (7) is linked together with the entry of sulfite test box (3), the export of sulfite test box (3) is linked together with the entry of filtrate tank (8), the output of sulfite test box (3) is connected with the input of control system (2), the output of control system (2) is connected with the control end of each oxidation fan (1).

2. The apparatus for real-time control of the oxidation process of a wet desulfurization slurry according to claim 1, wherein a sampling port of the gypsum slurry main pipe (4) is communicated with an inlet of the hydrocyclone (7) through a pump (6).

3. The device for controlling the oxidation process of the wet desulphurization slurry in real time as claimed in claim 1, wherein the bottom outlet of the hydrocyclone (7) is communicated with the inlet of the vacuum belt conveyor (5).

4. The apparatus for real-time control of oxidation process of wet desulfurization slurry according to claim 1, wherein the sulfite test chamber (3) comprises a chamber body and a redox electrode, a calcium ion online tester, a PH meter, an oxygen dissolution meter and a thermometer arranged on the chamber body.

5. The apparatus for real-time control of the oxidation process of wet desulfurization slurry according to claim 4, wherein the box body comprises an elongated rectangular parallelepiped tank and a perforated cover plate fixed at an opening at the top of the elongated rectangular parallelepiped tank, wherein the redox electrode, the calcium ion online tester, the PH meter, the dissolved oxygen meter and the thermometer are all inserted into a through hole on the perforated cover plate.