A high-salt waste liquid pretreatment system and incineration system

Abstract

The utility model provides a kind of high-salt waste liquid pretreatment system and incineration system.The pretreatment system includes sequentially connected feed unit, pretreatment unit, air supply unit and air induction unit;Feed unit includes auxiliary fuel lance and waste liquid lance;Pretreatment unit includes sequentially interconnected combustion chamber and cooling device of burner body;Auxiliary fuel lance, waste liquid lance are connected with burner body respectively;Air supply unit includes air blower, air blower is connected with burner body, combustion chamber respectively;The inlet of air induction unit is connected with the gas outlet of cooling device.The pretreatment system can be based on the coordinated cooperation of feed unit, air supply unit and other units, realize the pre-temperature control combustion of high-salt waste liquid, be conducive to the separation of organic matter and salt in high-salt waste liquid, remove salt in high-salt waste liquid, solve the plugging problem of incineration system, prolong the operation cycle of subsequent device.

Description

Technical Field

[0001] This utility model belongs to the field of hazardous waste incineration technology, specifically relating to a high-salt waste liquid pretreatment system and an incineration system. Background Technology

[0002] According to market feedback, the amount of high-salt waste liquid is gradually increasing. The melting point of salt is usually between 600 and 900°C, which is lower than the requirement of ≥1100°C for the flue gas temperature at the incinerator outlet. When too much salt enters the incineration unit, the flue gas temperature at the incinerator outlet drops sharply, resulting in the accumulation of solid salt at the outlet. This can cause blockage of the slag outlet, severe coking of the incinerator, downstream equipment, and flue, which not only increases operating costs but also requires frequent shutdowns for cleaning, hindering the long-term stable operation of the incineration system. Utility Model Content

[0003] To overcome the problem of salt in waste liquid damaging incineration equipment, this invention provides a high-salt waste liquid pretreatment system and an incineration system. This pretreatment system, through the coordinated operation of the feeding unit, air supply unit, and other units, achieves pre-temperature controlled combustion of the high-salt waste liquid, facilitating the separation of organic matter and salt in the waste liquid and ensuring that the heat loss on ignition of the high-salt waste liquid slag is less than 5%. In this pretreatment system, the cooling device of the pretreatment unit can control the temperature of the outlet flue gas to be lower than the melting point of salt, which is beneficial for the thorough removal of salt, reducing the salt content entering subsequent treatment equipment, and ensuring the long-term stable operation of the subsequent treatment equipment.

[0004] The present invention solves the above-mentioned technical problems through the following technical solution:

[0005] This invention provides a high-salt waste liquid pretreatment system, comprising a feeding unit, a pretreatment unit, an air supply unit, and an induced draft unit connected in sequence. The feeding unit includes an auxiliary fuel spray gun and a waste liquid spray gun, which are used to atomize the auxiliary fuel and the waste liquid, respectively. The pretreatment unit includes a burner body, a combustion chamber, and a cooling device connected in sequence. The auxiliary fuel spray gun and the waste liquid spray gun are connected to the burner body. The air supply unit includes a blower connected to the burner body and the combustion chamber. The inlet of the induced draft unit is connected to the gas outlet of the cooling device, and the induced draft unit is used to introduce the gas after the pretreatment unit into the subsequent treatment device.

[0006] In this invention, the high-salt waste liquid is a waste liquid conventionally understood in the art, wherein the mass content of soluble salts is >2%, such as distillation residue containing sodium salts, potassium salts, sulfates, etc. The pretreatment system of this invention renders the organic matter in the waste liquid harmless without altering the form of the salts in the waste liquid.

[0007] In this invention, the combination of the pretreatment unit and the air supply unit helps to form a reasonable combustion environment in the combustion chamber, ensuring that the combustible components in the waste liquid can be separated from the salt. The above-mentioned high-salt waste liquid pretreatment system can make the heat loss on ignition of the slag less than 5%, which meets the specifications and can prevent the salt from forming coke in the system.

[0008] In this invention, the auxiliary fuel spray gun and the waste liquid spray gun can be devices that atomize materials, such as a single-channel spray gun. The atomized auxiliary fuel and waste liquid are beneficial to the stable operation of the combustion chamber. The auxiliary fuel can be adjusted according to the characteristics of the waste liquid and the operating conditions of the system to maintain the temperature of the combustion chamber.

[0009] In this invention, the subsequent processing device generally includes an incineration device or an incinerator.

[0010] In some embodiments, the auxiliary fuel spray gun includes a two-fluid spray gun for atomizing auxiliary fuel with compressed air.

[0011] In some embodiments, the waste liquid spray gun includes a two-fluid spray gun for atomizing waste liquid with compressed air.

[0012] In this invention, the two-fluid spray gun uses compressed air to atomize auxiliary fuel and inject it into the burner body, allowing it to fully contact the atomized flue gas for heat and mass transfer. Firstly, it controls the flue gas temperature at the pretreatment unit outlet, causing salts in the flue gas to solidify. Secondly, the spray gun promotes airflow interaction, causing condensed salt particles in the flue gas to collide and increase in size, which is beneficial for sedimentation. Using the aforementioned two-fluid spray gun to atomize auxiliary fuel or waste liquid achieves more stable and better results.

[0013] In a specific implementation, the feeding unit further includes an auxiliary fuel supply device and a waste liquid supply device; the auxiliary fuel supply device is connected to the auxiliary fuel spray gun through a first pipe, and an auxiliary fuel regulating device is provided on the first pipe; the waste liquid supply device is connected to the waste liquid spray gun through a second pipe, and a waste liquid regulating device is provided on the second pipe; the auxiliary fuel regulating device and the waste liquid regulating device are respectively electrically connected to the instrumentation and control system to control the feeding amount of auxiliary fuel and waste liquid.

[0014] In some embodiments, an ignition device is provided inside the burner body, and the ignition device is located at the outlet of the auxiliary fuel spray gun for igniting the auxiliary fuel sprayed by the auxiliary fuel spray gun.

[0015] In a specific embodiment, the upper part of the side wall of the burner body is provided with an opening for installing the auxiliary fuel spray gun; the lower part of the side wall of the burner body is provided with an opening for installing the waste liquid spray gun; and the bottom of the burner body is provided with a primary air nozzle, which is connected to the blower.

[0016] Those skilled in the art should know that the part above the centerline of the burner body is called the upper part of the burner body, and the part below the centerline of the burner body is called the lower part of the burner body.

[0017] In a preferred embodiment, the pretreatment unit includes a pretreatment furnace, and the combustion chamber and the cooling device are both located in the pretreatment furnace; the burner body is installed on the pretreatment furnace; the combustion chamber includes a furnace body and refractory material; the combustion chamber is provided with a secondary air nozzle, and the secondary air nozzle is connected to the fan.

[0018] In this invention, the temperature of the combustion chamber can be adjusted according to the characteristics of the combustibles in the waste liquid, and is usually in the range of 400-700℃; the outlet temperature of the pretreatment furnace can be adjusted according to the characteristics of the salt in the waste liquid, and is usually in the range of 400-600℃.

[0019] In this utility model, the connection between the combustion chamber and the cooling device includes the following structures: Structure 1: The combustion chamber and the cooling device each include an independent chamber, and the outlet of the combustion chamber is connected to the inlet of the cooling device; Structure 2: The combustion chamber has an internal chamber that is connected to the induced draft unit, and the cooling device is located inside the internal chamber.

[0020] In some embodiments, the pretreatment unit further includes a slag discharge device located at the bottom of the cooling device for discharging the slag formed after cooling.

[0021] In some embodiments, the high-salt waste liquid pretreatment system further includes a dust removal unit; the dust removal unit is located between the pretreatment unit and the induced draft unit; the dust removal unit can remove solid salt in the flue gas that has not formed large particles of slag, thereby further removing salt from the flue gas.

[0022] In a specific implementation, the dust removal unit includes a dust collector and an ash discharge device located at the bottom of the dust collector. The inlet of the dust collector is connected to the outlet of the cooling device, and the outlet of the dust collector is connected to the inlet of the induced draft fan of the induced draft unit.

[0023] In this invention, the induced draft unit can effectively overcome the resistance of flue gas in the pretreatment system, so that the interior of the pretreatment system is in a full negative pressure mode, avoiding flue gas leakage and affecting the surrounding environment; so that the flue gas can be introduced into the subsequent treatment device (such as: incineration device), which is conducive to the stable operation of the subsequent treatment device; to achieve isolation between the pretreatment system and the subsequent treatment device; and when the pretreatment system needs to be shut down for maintenance, it will not affect the normal operation of the subsequent treatment device.

[0024] In some embodiments, the burner body is provided with a monitoring device for controlling the safe and stable operation of the burner body; the monitoring device includes a flame detector, a thermometer, a pressure gauge and a flow meter.

[0025] In this invention, the high-salt waste liquid pretreatment system operates under full negative pressure, wherein the combustion chamber is under slight negative pressure, ranging from -20 Pa to -50 Pa. This facilitates flue gas collection and allows the vast majority of the solidified waste salt from the cooling device to enter the slag discharge device or dust collector, maximizing waste salt collection and ensuring all flue gas enters the subsequent treatment devices.

[0026] This utility model also provides a high-salt waste liquid incineration system, which includes the high-salt waste liquid pretreatment system and incineration device as described above; the outlet of the induced draft unit is connected to the incineration device.

[0027] This utility model has at least the following beneficial effects:

[0028] 1. The pretreatment system of this utility model can separate most of the salt (60-80%) from the waste liquid, greatly reducing the salt content entering the subsequent treatment device. It has a positive effect on the refractory materials, coking and ash accumulation of the subsequent treatment device (such as: incineration device), which is conducive to the long-term operation of the subsequent treatment device.

[0029] 2. This utility model achieves automatic control of the combustion chamber temperature field by atomizing auxiliary fuel and waste liquid and controlling the feed amount of auxiliary fuel and waste liquid; furthermore, it can be adjusted according to the combustible composition characteristics of high-salt waste liquid to control the heat loss on ignition of slag within the range of ≤5%.

[0030] 3. This utility model can automatically control the outlet flue gas temperature of the pretreatment unit, so that the temperature of the flue gas generated by the pretreatment unit is lower than the melting point of the salt, and the salt in the flue gas is solid, thus avoiding coking and blockage.

[0031] 4. This utility model can isolate the pretreatment system from the subsequent treatment device, so that the subsequent treatment device can continue to operate when the pretreatment system is shut down for maintenance, thus enabling the main incineration device to operate for a long period of time. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the high-salt waste liquid pretreatment system of this utility model.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1-Auxiliary fuel supply device, 2-Auxiliary fuel regulating device, 3-Auxiliary fuel spray gun, 4-Waste liquid supply device, 5-Waste liquid regulating device, 6-Waste liquid spray gun, 7-Burner body, 8-Instrumentation and control system, 9-Blower, 10-Combustion chamber, 11-Cooling device, 12-Slag discharge device, 13-Dust collector, 14-Ash discharge device, 15-Induced draft fan. Detailed Implementation

[0035] To enable those skilled in the art to understand the features and effects of this utility model, the terms and expressions mentioned in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding this utility model, and in case of conflict, the definitions in this specification shall prevail.

[0036] In this document, the terms “contains,” “includes,” “containing,” and similar terms encompass the meanings of “basically composed of” and “composed of.” For example, when this document discloses “A contains B and C,” “A is basically composed of B and C” and “A is composed of B and C” should be considered as having been disclosed in this document.

[0037] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0038] Unless otherwise specified, percentages in this article refer to mass percentages.

[0039] For the sake of brevity, not all possible combinations of the technical features of each embodiment are described in this document. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features of each embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0040] Example 1

[0041] This embodiment discloses a high-salt waste liquid pretreatment system; Figure 1 This is a schematic diagram of the high-salt waste liquid pretreatment system of this utility model.

[0042] This high-salt waste liquid pretreatment system includes a feeding unit, a pretreatment unit, an air supply unit, a dust removal unit, an induced draft unit, and an instrumentation and control system. Among them:

[0043] The feeding unit includes an auxiliary fuel supply device 1 and an auxiliary fuel spray gun 3, a waste liquid supply device 4 and a waste liquid spray gun 6, and supporting pipelines. The auxiliary fuel supply device 1 and the auxiliary fuel spray gun 3 are connected via a first pipeline, which is equipped with an auxiliary fuel regulating device 2 electrically connected to the instrumentation and control system 8. The auxiliary fuel spray gun 3 is a two-fluid spray gun that uses compressed air to atomize the auxiliary fuel. The waste liquid supply device 4 and the waste liquid spray gun 6 are connected via a second pipeline, which is equipped with a waste liquid regulating device 5 electrically connected to the instrumentation and control system 8. The waste liquid spray gun 6 is also a two-fluid spray gun that uses compressed air to atomize the waste liquid.

[0044] The pretreatment unit includes a burner body 7 and a pretreatment furnace arranged in sequence. An auxiliary fuel spray gun 3, an ignition device, and a waste liquid spray gun 6 are installed sequentially from top to bottom on the burner body 7. The ignition device is located at the outlet of the auxiliary fuel spray gun 3 to ignite the auxiliary fuel atomized by the auxiliary fuel spray gun 3. The burner body 7 is mounted on the pretreatment furnace and has a primary air nozzle located at the bottom of the burner body 7 and connected to a fan to distribute the airflow entering the pretreatment unit from the fan, thus stabilizing the flame. The pretreatment furnace includes a combustion chamber 10, a cooling device 11, and a slag discharge device arranged in sequence. 12. The combustion chamber 10 consists of a furnace body and refractory materials, and has an internal chamber that is connected to the induced draft unit. The cooling device 11 is located inside the chamber. The atomized high-salt waste liquid is placed in the combustion chamber 10 and burned under set conditions, with the combustion temperature controlled by auxiliary fuel. The cooling device 11 at the rear of the combustion chamber 10 can control the outlet flue gas temperature according to the material characteristics, so that the salt and impurities in the outlet flue gas become solid. Part of the slag is discharged from the slag discharge device at the bottom of the cooling device 11, and the other part becomes fly ash and is carried away by the flue gas. The burner body 7 is equipped with a monitoring device for controlling the safe and stable operation of the burner body 7. The monitoring device includes a flame detector, thermometer, pressure gauge and flow meter, which is electrically connected to the instrumentation and control system 8.

[0045] The air supply unit includes a blower 9, supporting pipelines and instrumentation and control system; the blower 9 is connected to the primary air nozzle of the burner body 7 and the secondary air nozzle of the combustion chamber 10 through pipelines to provide the air required for combustion and control the stable operation of the pretreatment unit.

[0046] The dust removal unit includes a dust collector 13 and an ash discharge device 14; the inlet of the dust collector 13 is connected to the outlet of the cooling device 11, and the outlet of the dust collector 13 is connected to the inlet of the induced draft fan 15 of the induced draft unit; the dust collector 13 separates the salt in the flue gas at the outlet of the pretreatment furnace and discharges it from the ash discharge device 14 at the bottom of the dust collector 13.

[0047] The induced draft unit includes an induced draft fan 15 and a flue; the induced draft fan 15 overcomes the resistance of the pretreatment furnace, dust collector 13 and flue, and provides power for the flue gas to be sent into the subsequent incineration unit.

[0048] The high-salt waste liquid pretreatment system of this embodiment can remove most of the salt in the waste liquid, reduce the damage of salt to the refractory materials of the incineration unit, and reduce the hazards to safe and stable operation of the flue gas system such as ash accumulation and slagging.

[0049] Example 2

[0050] This embodiment discloses the method of using the high-salt waste liquid pretreatment system of Example 1, which includes the following process:

[0051] The pretreatment unit operates under a slight negative pressure, typically controlled between -20 Pa and -60 Pa. Auxiliary fuel stored in the auxiliary fuel supply unit and high-salt waste liquid stored in the waste liquid supply unit are injected into the incinerator body through auxiliary fuel and waste liquid spray guns, respectively, for combustion, achieving separation of salt and combustibles in the waste liquid. During this process, the temperature field of the combustion chamber can be adjusted by controlling the auxiliary fuel regulating device, waste liquid regulating device, and air supply unit, which are electrically connected to the instrumentation and control system. By controlling the waste liquid feed rate, auxiliary fuel consumption, and air supply rate, the temperature of the combustion chamber is controlled between 400 and 700°C, ensuring the separation of salt and combustibles and guaranteeing a slag loss on ignition of <5%. The slag loss on ignition is obtained by burning the slag from the pretreatment unit according to specifications and calculating the percentage of weight loss relative to the weight before burning (surface moisture should be removed before burning).

[0052] The cooling device at the rear of the combustion chamber controls the outlet flue gas temperature of the pretreatment unit, keeping it below the melting point of the salt in the waste liquid. This ensures that part of the crystallized waste liquid enters the slag discharge device of the cooling device, while the other part is collected by the dust collector. After passing through this cooling device, the temperature of the flue gas is below the melting point of the salt, typically controlled between 400 and 600°C.

[0053] The dust removal unit located downstream of the pretreatment unit removes solid salt particles from the flue gas; the induced draft fan downstream of the dust removal unit overcomes the flue gas resistance of the pretreatment system and sends the flue gas into the incineration unit (main incinerator); after the pretreatment system, most of the salt in the high-salt waste liquid can be removed.

[0054] When the pretreatment system is severely coked, the pretreatment system and the main incinerator can be isolated. Only the pretreatment system needs to be shut down for maintenance, while the main incinerator can continue to operate, achieving stable long-term operation of the main incinerator.

[0055] When the pretreatment system is severely coked, the pretreatment system and the main incinerator can be isolated by setting a valve control after the induced draft fan and closing the valve after the induced draft fan. Only the pretreatment system needs to be shut down for maintenance, while the main incinerator can continue to operate, achieving stable long-term operation of the main incinerator.

[0056] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the principles of the present utility model should be included within the protection scope of the present utility model.

[0057] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A high-salt wastewater pretreatment system, characterized in that, It includes a feeding unit, a pretreatment unit, an air supply unit, and an exhaust unit connected in sequence; The feeding unit includes an auxiliary fuel spray gun and a waste liquid spray gun; the auxiliary fuel spray gun and the waste liquid spray gun are respectively used to atomize the auxiliary fuel and the waste liquid. The pretreatment unit includes a burner body, a combustion chamber, and a cooling device arranged in sequence; the auxiliary fuel spray gun and the waste liquid spray gun are respectively connected to the burner body. The air supply unit includes a blower, which is connected to the burner body and the combustion chamber respectively. The inlet of the exhaust fan unit is connected to the gas outlet of the cooling device, and the exhaust fan unit is used to introduce the gas after the pretreatment unit into the subsequent treatment device.

2. The high-salt wastewater pretreatment system as described in claim 1, characterized in that, The auxiliary fuel spray gun includes a two-fluid spray gun, used to atomize auxiliary fuel using compressed air; The waste liquid spray gun includes a two-fluid spray gun, used to atomize waste liquid using compressed air.

3. The high-salt wastewater pretreatment system as described in claim 2, characterized in that, The feeding unit also includes an auxiliary fuel supply device and a waste liquid supply device; The auxiliary fuel supply device is connected to the auxiliary fuel spray gun through a first pipe, and an auxiliary fuel regulating device is provided on the first pipe. The waste liquid supply device is connected to the waste liquid spray gun through a second pipe, and a waste liquid regulating device is provided on the second pipe. The auxiliary fuel regulating device and the waste liquid regulating device are electrically connected to the instrumentation and control system, respectively, and are used to control the feed rate of auxiliary fuel and waste liquid.

4. The high-salt wastewater pretreatment system as described in claim 1, characterized in that, An ignition device is provided inside the burner body. The ignition device is located at the outlet of the auxiliary fuel spray gun and is used to ignite the auxiliary fuel sprayed by the auxiliary fuel spray gun.

5. The high-salt wastewater pretreatment system as described in claim 4, characterized in that, An opening for installing the auxiliary fuel spray gun is provided on the upper part of the side wall of the burner body. An opening for installing the waste liquid spray gun is provided on the lower part of the side wall of the burner body. The burner body has a primary air nozzle at its bottom, which is connected to the blower.

6. The high-salt wastewater pretreatment system as described in claim 5, characterized in that, The pretreatment unit includes a pretreatment furnace, and the combustion chamber and the cooling device are both located in the pretreatment furnace; the burner body is installed on the pretreatment furnace; The combustion chamber includes a furnace body and refractory material; the combustion chamber is provided with a secondary air nozzle, which is connected to the blower.

7. The high-salt wastewater pretreatment system as described in claim 1, characterized in that, The pretreatment unit also includes a slag discharge device, which is located at the bottom of the cooling device and is used to discharge the slag formed after cooling.

8. The high-salt wastewater pretreatment system as described in claim 1, characterized in that, The high-salt waste liquid pretreatment system also includes a dust removal unit; the dust removal unit is located between the pretreatment unit and the exhaust fan unit; The dust removal unit includes a dust collector and an ash discharge device located at the bottom of the dust collector. The inlet of the dust collector is connected to the outlet of the cooling device, and the outlet of the dust collector is connected to the inlet of the induced draft fan of the induced draft unit.

9. The high-salt wastewater pretreatment system as described in claim 1, characterized in that, The burner body is equipped with a monitoring device for controlling the safe and stable operation of the burner body; the monitoring device includes a flame detector, a thermometer, a pressure gauge and a flow meter; the monitoring device is electrically connected to the instrumentation and control system.

10. A high-salt waste liquid incineration system, characterized in that, It includes a high-salt waste liquid pretreatment system and an incineration device as described in any one of claims 1-9; the outlet of the induced draft unit is connected to the incineration device.

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