Phosphate-containing waste liquid and waste gas incineration flue gas multi-stage treatment system

Abstract

The utility model provides a multi-stage treatment system for incineration flue gas of waste liquid and waste gas containing phosphate. The multi-stage treatment system comprises a cooling settling furnace and a denitration settling furnace, the input end of the cooling settling furnace is communicated with the smoke output end of the incinerator, the upper part of the cooling settling furnace is a first smoke channel, and the lower part of the cooling settling furnace is a settling chamber; the first flue gas passage is communicated with the input end of the cooling settling furnace, and a first heat exchange assembly and a second heat exchange assembly are arranged in the first flue gas passage; the denitration settling furnace input end of the denitration settling furnace is communicated with the cooling settling furnace output end of the cooling settling furnace; the upper part is provided with a denitration assembly communicated with the input end of the denitration settling furnace, and the lower part is provided with a second flue gas passage; and a third heat exchange assembly is arranged on the second flue gas passage. According to the phosphate-containing waste liquid and waste gas incineration flue gas multi-stage treatment system, by controlling the temperature, stage sedimentation and denitration treatment can be conducted on the flue gas, and salt in the flue gas can be recycled while the flue gas obtained after waste liquid incineration is purified.

Description

Technical Field

[0001] The present application relates to the field of waste liquid and waste gas incineration, and in particular to a multi-stage flue gas treatment system for the incineration of phosphate-containing waste liquid and waste gas. Background Art

[0002] BDO (1,4-butanediol) and ethylene glycol are important organic and fine chemical raw materials, widely used in various fields. Both BDO and ethylene glycol plants generate large amounts of waste gas and liquid during operation. In addition to organic waste liquid, these waste liquids also contain two inorganic salts, disodium hydrogen phosphate and sodium dihydrogen phosphate. Physical property analysis shows that under high-temperature incineration, disodium hydrogen phosphate and sodium dihydrogen phosphate decompose to form sodium peroxide and phosphorus oxide (phosphorus pentoxide). Sodium peroxide reacts with carbon dioxide and water in the flue gas to form sodium carbonate, and sodium peroxide reacts with water vapor in the flue gas to form sodium hydroxide.

[0003] In the prior art, waste gas and liquid generated by BDO and ethylene glycol plants are typically treated through distillation or incineration. Distillation requires high process control, suffers from low efficiency, and is costly. Incineration, on the other hand, produces high levels of salts such as sodium carbonate, sodium peroxide, sodium hydroxide, and gaseous phosphorus oxide. The resulting flue gas concentrates in the incinerator, which can easily lead to corrosion and slagging and blockage in the incineration system. This requires frequent downtime for inspection and cleaning, and can even cause production accidents, impacting the incineration system's efficiency and operational safety. Utility Model Content

[0004] In response to the above problems, the present application provides a multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas, which can perform staged sedimentation and denitrification treatment on the flue gas by controlling the temperature. While purifying the flue gas after waste liquid incineration, it can also recover the salt in the flue gas.

[0005] To achieve the purpose of this application, this application provides the following technical solutions:

[0006] The present application provides a multi-stage flue gas treatment system for incineration of phosphate-containing waste liquid, comprising: a cooling and settling furnace, a denitrification and settling furnace;

[0007] The cooling and settling furnace input end of the cooling and settling furnace is connected to the flue gas output end of the incinerator, the upper part is a first flue gas passage, and the lower part is a settling chamber; the first flue gas passage is connected to the cooling and settling furnace input end, and a first heat exchange component and a second heat exchange component are arranged therein;

[0008] The denitrification sedimentation furnace input end of the denitrification sedimentation furnace is connected to the cooling sedimentation furnace output end of the cooling sedimentation furnace; the upper part has a denitrification component connected to the denitrification sedimentation furnace input end, and the lower part has a second flue gas passage; the second flue gas passage has a third heat exchange component.

[0009] In a possible implementation, a baffle is provided on the top of the settling chamber; the baffle extends into the interior of the settling chamber, and the bottom of the baffle is lower than the bottom of the output end of the cooling and settling furnace.

[0010] In a possible implementation, the output end of the cooling and settling furnace further has a fourth heat exchange component.

[0011] In a possible implementation, a first soot blowing component is provided in the flue gas passage of the cooling and settling furnace, for blowing away solid particles on the surfaces of the first heat exchange component and the second heat exchange component.

[0012] In a possible implementation, a third soot blowing component is provided in the bottom passage of the denitration settling furnace for blowing away solid particles on the surface of the third heat exchange component.

[0013] In a possible implementation, the bottom of the sedimentation chamber has a first discharge port.

[0014] In a possible implementation, the bottom of the bottom passage of the denitration sedimentation furnace is provided with a second discharge port.

[0015] In a possible implementation, the denitration component is a vertical flow denitration reactor.

[0016] In one possible implementation, the denitrification component includes: a denitrification agent spraying component and a partition; the denitrification agent spraying component is used to spray the denitrification agent into the interior of the denitrification sedimentation furnace, and the partition can be opened and closed, and when closed, the interior of the denitrification sedimentation furnace is divided into multiple spaces.

[0017] In a possible implementation, a second soot blowing assembly is provided at the partition of the denitration settling furnace for blowing away solid particles on the surface of the partition.

[0018] Beneficial effects:

[0019] The multi-stage flue gas treatment system for incineration of phosphate-containing waste liquid and waste gas provided in this application can perform phased sedimentation treatment on the flue gas generated by incineration, separate and recover substances such as sodium carbonate, sodium peroxide, sodium hydroxide, and gaseous phosphorus oxide in the flue gas, and perform denitrification treatment. This achieves efficient and continuous incineration treatment of the waste gas and waste liquid generated by the BDO unit and ethylene glycol unit during operation, avoiding slagging, blockage, and corrosion problems caused by incineration, while recovering substances such as sodium carbonate, sodium peroxide, sodium hydroxide, and gaseous phosphorus oxide in the waste liquid and waste gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present application and form a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not limit the present application.

[0021] Figure 1 A schematic structural diagram of a multi-stage system for treating flue gas from the incineration of phosphate-containing waste liquid provided in an embodiment of the present application;

[0022] Figure 2 A schematic structural diagram of a heat exchange component of a multi-stage flue gas treatment system for incineration of phosphate-containing waste liquid provided in an embodiment of the present application;

[0023] Figure 3 A schematic structural diagram of a heat exchange component of a multi-stage flue gas treatment system for incineration of phosphate-containing waste liquid provided in an embodiment of the present application.

[0024] Reference numerals:

[0025] 100 - cooling and settling furnace, 110 - cooling and settling furnace input, 120 - second heat exchange component, 130 - third heat exchange component, 140 - settling chamber, 141 - baffle, 142 - standby air input, 150 - fourth heat exchange component, 160 - cooling and settling furnace output, 170 - first discharge port, 180 - first sootblowing component;

[0026] 200-denitrification sedimentation furnace, 210-denitrification sedimentation furnace input end, 220-denitrification agent spraying assembly, 230-partition, 240-fifth heat exchange assembly, 250-denitrification sedimentation furnace output end, 260-second discharge port, 270-second soot blowing assembly, 280-third soot blowing assembly. DETAILED DESCRIPTION

[0027] To make the objectives, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0028] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the technical features indicated. Thus, features specified as "first" or "second" may explicitly or implicitly include one or more of such features; and in the description of this application, unless otherwise specified, "plurality" means two or more.

[0029] Example 1

[0030] Figure 1-3 A multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas provided in an embodiment of the present application includes: a cooling and settling furnace 100, a denitrification and settling furnace 200;

[0031] The cooling and settling furnace 100 has a cooling and settling furnace input end 110 connected to a flue gas output end of the incinerator, an upper portion of which is a first flue gas passage, and a lower portion of which is a settling chamber 140; the first flue gas passage is connected to the cooling and settling furnace input end 110, and is provided with a first heat exchange component 120 and a second heat exchange component 130;

[0032] The denitrification sedimentation furnace input end 210 of the denitrification sedimentation furnace 200 is connected to the cooling sedimentation furnace output end 160 of the cooling sedimentation furnace 100; the upper part has a denitrification component connected to the denitrification sedimentation furnace input end 210, and the lower part has a second flue gas passage; the second flue gas passage has a third heat exchange component 240.

[0033] Optionally, the first heat exchange component 120 is used to cool the flue gas temperature, the second heat exchange component 130 is used to control the flue gas temperature to remain within a first preset temperature range, and the third heat exchange component 240 is used to cool the flue gas, thereby improving the sedimentation efficiency.

[0034] In a possible implementation, a baffle 141 is provided on the top of the settling chamber 140 ; the baffle 141 extends into the settling chamber 140 , and the bottom of the baffle 141 is lower than the bottom of the output end 160 of the cooling and settling furnace.

[0035] The settling chamber is a conical shell, and the baffle 141 allows the fourth flue gas to sink into the settling chamber. In the process of raising the output cooling settling furnace 100, as many solid particles in the fourth flue gas as possible are settled into the settling chamber 140.

[0036] In a possible implementation, the cooling and settling furnace output end 160 further includes a fourth heat exchange component 150 .

[0037] The fourth heat exchange component 150 is used to maintain the flue gas within a second preset temperature range when entering the denitrification settling furnace 200, so as to facilitate efficient denitrification reaction between the flue gas and the denitrification agent.

[0038] In a possible embodiment, a first soot blowing assembly 180 is provided in the flue gas passage of the cooling and settling furnace 100 for blowing away solid particles on the surfaces of the first heat exchange assembly 120 and the second heat exchange assembly 130 .

[0039] Optionally, the first sootblowing assembly 180 is a sonic sootblower.

[0040] In a possible embodiment, a third soot blowing component 280 is provided in the bottom passage of the denitration settling furnace 200 for blowing away solid particles on the surface of the third heat exchange component 240 .

[0041] Optionally, the third sootblowing assembly 280 is a sonic sootblower.

[0042] In a possible embodiment, the bottom of the settling chamber 140 has a first discharge port 170 for discharging solid matter settled at the bottom of the settling chamber.

[0043] In a possible embodiment, the bottom of the bottom passage of the denitration settling furnace 200 has a second discharge port 260 for discharging solid matter settled at the bottom of the denitration settling furnace 200 .

[0044] In one possible embodiment, the denitration component is a vertical flow denitration reactor.

[0045] Among them, the vertical flow denitrification reactor includes: a baffle door, an injection grid, an SCR reactor, and a catalyst;

[0046] The horizontal section of the SCR reactor is equipped with flue gas diversion and distribution optimization devices, as well as an ammonia injection grid. The vertical section of the reactor houses the catalyst bed. The reactor utilizes a fixed-bed vertical channel design, initially equipped with two layers, with one layer reserved for future installation of catalyst should denitrification efficiency fall below the guaranteed value. This serves as a backup measure to enhance denitrification efficiency and extend the effective catalyst life. Each reactor is equipped with one reactor. Each reactor is designed to have three layers, with only two layers installed initially. The reactor is a vertical welded steel vessel with an internal catalyst support structure designed to withstand internal pressure, seismic loads, smoke, catalyst loads, and thermal stresses. The reactor shell is equipped with reinforcement ribs and insulation. Catalyst is loaded into the reactor through a side door via an external catalyst loading system.

[0047] The injection grid includes a supply box, an injection grid, an injection hole, and an injection system. The injection system is equipped with a throttle valve and a throttle orifice plate. While continuously analyzing the NOx concentration, the necessary amount of ammonia is adjusted to spray ammonia from the ammonia injection grid; thereby, ammonia is evenly distributed in the flue gas and is convenient for adjusting the NH3 / NO X Adjustment of molar ratio.

[0048] Optionally, the denitrification agent includes any one or more of liquid ammonia, urea and ammonia water.

[0049] In a possible embodiment, the denitrification component includes: a denitrification agent spraying component 220 and a partition 230; the denitrification agent spraying component 220 is used to spray the denitrification agent into the interior of the denitrification sedimentation furnace 200, and the partition 230 can be opened and closed, and when closed, the interior of the denitrification sedimentation furnace is divided into multiple spaces.

[0050] In a possible embodiment, a second sootblowing assembly 270 is provided at the partition 230 of the denitration settling furnace 200 for blowing away solid particles on the surface of the partition 230 .

[0051] In the several embodiments provided in this application, it should be understood that the disclosed systems, modules and methods can be implemented in other ways. For example, the module embodiments described above are merely illustrative. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of modules or units, which can be electrical, mechanical or other forms.

[0052] The above embodiments are intended only to illustrate the technical solutions of the present application and are not intended to limit them. The present application is not limited to the precise structures described above and illustrated in the accompanying drawings, and it cannot be assumed that the specific implementation of the present application is limited to these descriptions. For those skilled in the art of the present application, any changes and modifications made without departing from the concept of the present application should be deemed to fall within the scope of protection of the present application.

Claims

1. A multi-stage treatment system for flue gas from the incineration of phosphate-containing waste liquid and waste gas, characterized in that: include: A cooling and settling furnace (100) and a denitrification and settling furnace (200); The cooling and settling furnace input end (110) of the cooling and settling furnace (100) is connected to the flue gas output end of the incinerator, the upper portion is a first flue gas passage, and the lower portion is a settling chamber (140); the first flue gas passage is connected to the cooling and settling furnace input end (110), and a first heat exchange component (120) and a second heat exchange component (130) are arranged therein; The denitration settling furnace input end (210) of the denitration settling furnace (200) is connected to the cooling settling furnace output end (160) of the cooling settling furnace (100); the upper portion is provided with a denitration component connected to the denitration settling furnace input end (210), and the lower portion is provided with a second flue gas passage; and the second flue gas passage is provided with a third heat exchange component (240).

2. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 1 is characterized in that: The top of the settling chamber (140) is provided with a baffle (141); the baffle (141) extends into the interior of the settling chamber (140), and the bottom of the baffle (141) is lower than the bottom of the output end (160) of the cooling settling furnace.

3. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 1, characterized in that: The cooling and settling furnace output end (160) further comprises a fourth heat exchange component (150).

4. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 1, characterized in that: A first soot blowing component (180) is provided in the flue gas passage of the cooling and settling furnace (100) for blowing away solid particles on the surfaces of the first heat exchange component (120) and the second heat exchange component (130).

5. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 1, characterized in that: A third soot blowing assembly (280) is provided in the bottom passage of the denitration settling furnace (200) for blowing away solid particles on the surface of the third heat exchange assembly (240).

6. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 1, characterized in that: The bottom of the settling chamber (140) is provided with a first discharge port (170).

7. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 1, characterized in that: The bottom of the bottom passage of the denitration sedimentation furnace (200) is provided with a second discharge port (260).

8. The multi-stage flue gas treatment system for incineration of phosphate-containing waste liquid and waste gas according to claim 1, characterized in that: The denitration component is a vertical flow denitration reactor.

9. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 1, characterized in that: The denitration component comprises: a denitration agent spraying component (220) and a partition (230); the denitration agent spraying component (220) is used to spray the denitration agent into the interior of the denitration sedimentation furnace (200); the partition (230) can be opened and closed, and when closed, the interior of the denitration sedimentation furnace is divided into multiple spaces.

10. The multi-stage treatment system for phosphate-containing waste liquid and waste gas incineration flue gas according to claim 9, characterized in that: A second soot blowing assembly (270) is provided at the partition (230) of the denitration settling furnace (200) for blowing away solid particles on the surface of the partition (230).

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