A plasma furnace and method for jointly disposing of solid and liquid hazardous waste

Abstract

The present invention discloses a plasma furnace and method for jointly disposing of solid and liquid hazardous wastes, which relates to the field of hazardous waste disposal and solves the problems of insufficient disposal scope and disposal effect in traditional plasma hazardous waste disposal technologies. The furnace body includes an upper gas zone and a lower molten pool inside. The gas zone is connected to a solid hazardous waste feed inlet and a gas outlet, and the molten pool is connected to a slag outlet. A thermal plasma torch and a liquid hazardous waste feed sleeve are provided at the bottom of the furnace body. The thermal plasma torch generates a plasma flame, and the plasma flame passes upward through the bottom of the furnace body and is sprayed into the molten pool to heat and stir the molten pool, forming a stable slag circulation flow in the molten pool. The liquid hazardous waste is sprayed into the plasma flame from the bottom of the furnace body through the liquid hazardous waste feed sleeve and enters the molten pool together with the plasma flame. The effects of achieving both the oxidation and decomposition of organic pollutants and the solidification and capture of inorganic pollutants, and improving the applicable scope and efficiency of plasma hazardous waste disposal are achieved.

Description

Technical Field

[0001] The present invention relates to the field of hazardous waste disposal, and particularly to a plasma furnace and method for jointly disposing of solid and liquid hazardous wastes. Background Art

[0002] Thermal plasma hazardous waste disposal has advantages such as fast disposal rate, thorough disposal of harmful substances, and high volume reduction rate, and is becoming a hot technology in the field of hazardous waste disposal. For different types of hazardous wastes, the adopted thermal plasma disposal processes are not the same. For solid hazardous wastes, the thermal plasma disposal generally uses a plasma furnace as the reaction device and adopts a process route of "gasification and incineration of organic components and vitrification of inorganic components by melting".

[0003] Existing plasma furnaces generally have three defects. One is the uneven temperature distribution in the furnace, where heavy metals are prone to volatilize in the high-temperature area and solid wastes are not easily melted in the low-temperature area. The second is that the solid wastes are prone to float on the surface of the molten pool after entering the furnace, resulting in poor contact between harmful substances and the molten pool. The third is that the bottom of the molten pool is prone to excessive solidification of the slag due to heat dissipation, blocking the slag discharge port.

[0004] For liquid hazardous wastes, especially liquid organic hazardous wastes, the thermal plasma disposal generally adopts the method of injecting liquid organic hazardous wastes into the thermal plasma stream, and uses the characteristic that the plasma can break the molecular bonds of organic hazardous wastes to quickly oxidize and decompose them into inorganic gaseous small molecules. This method has a good removal effect on organic pollutants, but has a poor disposal effect on liquid hazardous wastes containing harmful substances such as heavy metals and radioactive elements.

[0005] The differences in the thermal plasma disposal processes for different types of hazardous wastes make it difficult to adopt a universal thermal plasma disposal process to achieve good disposal effects on various types of hazardous wastes. Some plasma hazardous waste disposal technologies adopt the method of separately setting feeding ports for solid and liquid hazardous wastes at the top of the plasma hazardous waste disposal equipment, or the method of mixing and feeding solid and liquid hazardous wastes, hoping to achieve the joint disposal of solid and liquid hazardous wastes, but the effect is not ideal;

[0006] First, after the liquid hazardous waste is fed from the top of the equipment, it starts to volatilize during the falling process and escapes from the gas outlet, resulting in incomplete disposal of the liquid hazardous waste. Second, due to the instability of the thermal plasma and the temperature difference inside the thermal plasma disposal equipment, the plasma concentration, temperature, and oxygen concentration experienced by the liquid hazardous waste often do not meet the requirements for complete decomposition. Third, if the liquid hazardous waste contains heavy metals, these heavy metal components are difficult to enter the molten pool and be locked by the glass body. Finally, since the plasma generation area of such technologies is generally located above the molten pool, the heating efficiency of the plasma for the molten pool is low, resulting in a series of problems such as high energy consumption, uneven temperature of the molten pool, and easy blockage of the slag discharge port. Summary of the Invention

[0007] The object of the present invention is to provide a plasma furnace for jointly disposing of solid and liquid hazardous wastes, which is used to solve the deficiencies in the disposal scope and disposal effect of the above-mentioned plasma hazardous waste disposal technology, and to provide a plasma disposal furnace and its usage method that can efficiently jointly dispose of solid and liquid hazardous wastes, can not only achieve the oxidative decomposition of organic pollutants, but also complete the solidification and capture of inorganic pollutants, so as to improve the applicable scope and efficiency of plasma hazardous waste disposal.

[0008] The above technical object of the present invention is achieved by the following technical solutions:

[0009] A plasma furnace for jointly disposing of solid and liquid hazardous wastes, including a furnace body. The interior of the furnace body includes a gas zone in the upper part and a molten pool in the lower part. The gas zone is connected to a solid hazardous waste feed port and a gas outlet, and the molten pool is connected to a slag outlet.

[0010] A thermal plasma torch and a liquid hazardous waste feed sleeve are provided at the bottom of the furnace body. The thermal plasma torch generates a plasma flame, and the plasma flame passes upward through the bottom of the furnace body and sprays into the molten pool, heating and stirring the molten pool to form a stable slag circulation in the molten pool.

[0011] The liquid hazardous waste is sprayed into the plasma flame from the bottom of the furnace body through the liquid hazardous waste feed sleeve and enters the molten pool together with the plasma flame.

[0012] Furthermore, the thermal plasma torch is located in the middle of the molten pool, and the direction of the slag circulation is upward in the middle of the molten pool and downward around the molten pool.

[0013] Furthermore, the liquid hazardous waste feed sleeve is externally connected to the thermal plasma torch, and the plasma flame passes through the liquid hazardous waste feed sleeve and then sprays into the molten pool from the bottom of the molten pool.

[0014] Furthermore, the inner wall of the liquid hazardous waste feed sleeve is provided with a protective gas spray port, a liquid hazardous waste spray port, and an oxidation gas spray port, and the bottom is provided with a protective gas inlet, a liquid hazardous waste inlet, and an oxidation gas inlet.

[0015] A protective gas channel is connected between the protective gas inlet and the protective gas spray port, a liquid hazardous waste channel is connected between the liquid hazardous waste inlet and the liquid hazardous waste spray port, and an oxidation gas channel is connected between the oxidation gas inlet and the oxidation gas spray port.

[0016] Furthermore, the protective gas is nitrogen or an inert gas, and the oxidation gas is pure oxygen, air, or oxygen-enriched air.

[0017] Furthermore, the thermal plasma torch is detachably connected to the liquid hazardous waste feed sleeve.

[0018] Furthermore, the thermal plasma torch uses air, nitrogen, water vapor, oxygen, inert gas or a mixture thereof as the plasma working medium.

[0019] Furthermore, inside the furnace body, water-cooled walls are provided on the side walls and the bottom of the molten pool part, and a heat-insulating refractory material layer is laid on the inner wall of other parts.

[0020] Furthermore, a heating device for preventing the condensation of the liquid slag in its vicinity is provided at the position of the slag outlet.

[0021] The purpose of the present invention also lies in providing a method for jointly disposing of solid and liquid hazardous wastes, which has the advantages of low energy consumption, thorough treatment of harmful components, fast disposal speed, high heavy metal capture rate, and stable molten pool.

[0022] The above technical objectives of the present invention are achieved through the following technical solutions:

[0023] A method for jointly disposing of solid and liquid hazardous wastes includes the following steps:

[0024] Step 1: Connect the thermal plasma torch to the liquid hazardous waste feeding sleeve.

[0025] Step 2: Feed the vitreous slag from the solid hazardous waste feeding port so that the vitreous slag accumulates in the furnace body to form a material bed.

[0026] Step 3: Turn on the water-cooling switch of the furnace body water-cooled wall and the liquid hazardous waste feeding sleeve, and open the protective gas inlet of the liquid hazardous waste feeding sleeve.

[0027] Step 4: Turn on the thermal plasma torch, and the plasma flame is sprayed into the furnace body to melt the vitreous slag, forming a vitreous molten pool. Under the continuous pushing of the plasma flame, the molten pool forms a stable circulation flow with the middle rising and the surrounding falling.

[0028] Step 5: If disposing of solid hazardous waste, feed the solid hazardous waste from the solid hazardous waste feeding port. The solid hazardous waste falls into the molten pool and is involved in the molten pool circulation. The organic components in the solid hazardous waste are decomposed into gaseous small molecules at the high temperature of the molten pool, and the inorganic components in the solid hazardous waste are quickly melted, and the harmful components are locked by the molten pool.

[0029] Step 6: If disposing of liquid hazardous waste, open the oxidation gas inlet and the liquid hazardous waste inlet. The oxidation gas and the liquid hazardous waste are respectively sprayed into the plasma flame from the oxidation gas nozzle and the liquid hazardous waste nozzle. The organic components in the liquid hazardous waste are quickly oxidized and decomposed in the plasma flame, and the inorganic components such as heavy metals in the liquid hazardous waste enter the molten pool along with the plasma flame and are absorbed and locked by the slag in the molten pool.

[0030] Step 7: When the height of the molten pool liquid level reaches the set high level, stop feeding, open the slag outlet, discharge the slag until the molten pool liquid level drops to the set low level, and then close the slag outlet;

[0031] Step 8: According to the type of hazardous waste to be disposed of, alternately perform the above Steps 5-7 to achieve continuous combined disposal of solid and liquid hazardous wastes;

[0032] Step 9: After the disposal is completed, stop feeding, close the oxidizing gas inlet, gradually reduce the power of the thermal plasma torch, and empty the slag;

[0033] Step 10: Turn off the thermal plasma torch, close the protective gas inlet, and let the system cool naturally.

[0034] Another object of the present invention is to provide another method for combined disposal of solid and liquid hazardous wastes, which is characterized by including the following steps:

[0035] Step 1: Sealingly connect the thermal plasma torch with the liquid hazardous waste feeding sleeve;

[0036] Step 2: Feed vitreous slag from the solid hazardous waste feed inlet, so that the vitreous slag accumulates in the furnace body to form a material bed;

[0037] Step 3: Open the water cooling switches of the furnace body water-cooled wall and the liquid hazardous waste feeding sleeve, and open the protective gas inlet of the liquid hazardous waste feeding sleeve;

[0038] Step 4: Turn on the thermal plasma torch, spray the plasma flame into the furnace body, melt the vitreous slag to form a vitreous molten pool, and under the continuous push of the plasma flame, the molten pool forms a stable circulation with the middle rising and the surrounding falling;

[0039] Step 5: Feed solid hazardous waste from the solid hazardous waste feed inlet, the solid hazardous waste falls into the molten pool and is involved in the molten pool circulation. The organic components in the solid hazardous waste are decomposed into gaseous small molecules at the high temperature of the molten pool, the inorganic components in the solid hazardous waste are quickly melted, and the harmful components are locked by the molten pool;

[0040] Step 6: Open the oxidizing gas inlet and the liquid hazardous waste inlet, the oxidizing gas and the liquid hazardous waste are respectively sprayed into the plasma flame from the oxidizing gas nozzle and the liquid hazardous waste nozzle. The organic components in the liquid hazardous waste are quickly oxidized and decomposed in the plasma flame, and the inorganic components in the liquid hazardous waste such as heavy metals enter the molten pool along with the plasma flame and are absorbed and locked by the slag in the molten pool;

[0041] Step 7: When the height of the molten pool liquid level reaches the set value, keep feeding, open the slag outlet, control the outflow rate of the slag, so that the amount of liquid slag generated and the amount of slag discharged maintain a dynamic balance, and the height of the molten slag liquid level in the furnace remains stable to achieve continuous feeding and slag discharging;

[0042] Step 8: After the disposal is completed, stop feeding, close the inlet of the oxidation gas, gradually reduce the power of the thermal plasma torch, and empty the slag.

[0043] Step 9: Turn off the thermal plasma torch and the inlet of the protective gas, and let the system cool naturally.

[0044] In summary, the present invention has the following beneficial effects:

[0045] Not only can a set of equipment be used to simultaneously achieve the efficient and harmless disposal of solid hazardous waste and liquid hazardous waste, but also it has a series of advantages such as low energy consumption, thorough treatment of harmful components, fast disposal speed, high heavy metal capture rate, and stable molten pool.

[0046] Using a single thermal plasma furnace to achieve the comprehensive disposal of liquid hazardous waste and solid hazardous waste, the device has a simple structure, a wide range of disposal objects, thorough disposal, and no secondary pollution.

[0047] The thermal plasma is injected from the bottom of the furnace body, driving the formation of a stable circulation in the molten pool, promoting the exchange of substances and energy inside the molten pool, realizing the uniformity of the composition and temperature of the molten pool, and avoiding problems such as local overheating of the molten pool and blockage of the slag outlet by the cooling of the slag at the bottom of the molten pool.

[0048] The circulation in the pool draws the solid hazardous waste fed into the furnace into the deep part of the molten pool by the circulation in the molten pool. The solid hazardous waste melts in the deep part of the molten pool, achieving full contact between the solid hazardous waste and the liquid slag in the molten pool, accelerating the melting of the solid hazardous waste, and promoting the locking of harmful components by the molten pool.

[0049] The liquid hazardous waste is disposed of thoroughly. The organic harmful components in the liquid hazardous waste are rapidly oxidized and decomposed in the plasma flame, and the residual components enter the molten pool for further reaction. Harmful substances such as heavy metals and radioactive components are absorbed and locked by the molten pool, avoiding secondary pollution.

[0050] The disposal objects and disposal methods of the thermal plasma furnace can be adjusted flexibly in real time according to needs, and there is no need to stop the machine during the adjustment process. Description of the Drawings

[0051] Figure 1 is the overall structural schematic diagram of the thermal plasma furnace for the combined disposal of solid and liquid hazardous waste provided by the present invention;

[0052] Figure 2 is the detailed schematic diagram of the connection part between the liquid hazardous waste feeding sleeve and the furnace body in the present invention.

[0053] In the figure, 1 is the molten pool; 2 is the plasma flame; 3 is the slag circulation; 4 is the solid hazardous waste feed inlet; 5 is the liquid hazardous waste feed sleeve; 6 is the gas zone; 7 is the gas outlet; 8 is the slag outlet; 9 is the thermal plasma torch; 10 is the water-cooled wall; 11 is the heat-insulating refractory layer; 12 is the protective gas nozzle; 13 is the liquid hazardous waste nozzle; 14 is the oxidation gas nozzle; 15 is the protective gas inlet; 16 is the protective gas channel; 17 is the liquid hazardous waste inlet; 18 is the oxidation gas inlet; 19 is the liquid hazardous waste channel; 20 is the oxidation gas channel; 21 is the plasma outlet; 22 is the self-sealing device; 23 is the slag adhering layer. Detailed implementation manners

[0054] The following further describes the detailed implementation manners of the present invention in conjunction with the accompanying drawings. This embodiment does not constitute a limitation to the present invention.

[0055] A plasma furnace for jointly disposing of solid and liquid hazardous waste, as Figure 1 shown, includes a furnace body. The interior of the furnace body includes a gas zone 6 in the upper part and a molten pool 1 in the lower part; the gas zone 6 communicates with the solid hazardous waste feed inlet 4 and the gas outlet 7; the molten pool 1 is composed of liquid slag and communicates with the slag outlet 8 at the bottom.

[0056] As Figure 1 shown, a thermal plasma torch 9 and a liquid hazardous waste feed sleeve 5 are provided at the bottom of the furnace body. The thermal plasma torch 9 generates a plasma flame 2, and the plasma flame 2 passes upward through the bottom of the furnace body and the liquid hazardous waste feed sleeve 5 and is sprayed into the furnace body to heat and stir the molten pool 1, and a stable slag circulation 3 is formed in the molten pool 1;

[0057] The thermal plasma torch 9 is located in the middle of the molten pool 1. The high-speed plasma flame 2 drives the liquid slag in the middle of the molten pool 1 to rise upward, and then a stable slag circulation 3 is formed in the molten pool 1, so that the direction of the slag circulation 3 is upward in the middle of the molten pool 1 and downward around the molten pool 1.

[0058] As Figure 1 shown, specifically, the solid hazardous waste feed inlet 4 is located at the top of the furnace body, the liquid hazardous waste feed sleeve 5 is located at the bottom of the furnace body, and the plasma flame 2 generated by the thermal plasma torch 9 is sprayed into the molten pool 1 from the bottom through the liquid hazardous waste feed sleeve 5; the gas outlet 7 is located above the side wall of the furnace body, and the slag outlet 8 is located on the side wall of the furnace body near the bottom of the molten pool 1.

[0059] As Figure 2As shown in the figure, the liquid hazardous waste feed sleeve 5 is externally connected to the thermal plasma torch 9, and the plasma flame 2 passes through the liquid hazardous waste feed sleeve 5 and then sprays into the bottom of the molten pool 1; the liquid hazardous waste feed sleeve 5 is a hollow structure made of metal and is water-cooled; a hole matching the outer diameter of the liquid hazardous waste feed sleeve 5 is opened in the center of the bottom of the furnace body, and the liquid hazardous waste feed sleeve 5 extends into the hole and is fixed in the center of the bottom of the furnace body, and the connection between the liquid hazardous waste feed sleeve 5 and the furnace body is kept sealed.

[0060] As Figure 2 shown in the figure, the inner wall of the liquid hazardous waste feed sleeve 5 is provided with a protective gas nozzle 12, a liquid hazardous waste nozzle 13 and an oxidation gas nozzle 14, and the bottom is provided with a protective gas inlet 15, a liquid hazardous waste inlet 17 and an oxidation gas inlet 18.

[0061] A protective gas channel 16 is connected between the protective gas inlet 15 and the protective gas nozzle 12, a liquid hazardous waste channel 19 is connected between the liquid hazardous waste inlet 17 and the liquid hazardous waste nozzle 13, and an oxidation gas channel 20 is connected between the oxidation gas inlet 18 and the oxidation gas nozzle 14;

[0062] The protective gas is used to prevent the high-temperature plasma flame 2 from ablating the liquid hazardous waste feed sleeve 5, and is nitrogen or an inert gas. After entering the liquid hazardous waste feed sleeve 5 from the protective gas inlet 15, it passes through the protective gas channel 16 and is sprayed into the plasma flame 2 from the protective gas nozzle 12;

[0063] The oxidation gas is pure oxygen, air or oxygen-enriched air. After the liquid hazardous waste is sprayed out from the liquid hazardous waste nozzle 13, it decomposes in the environment of the high temperature and high free radical groups of the plasma flame 2 and reacts with the oxidation gas to generate harmless gas small molecules;

[0064] The flow rates of the protective gas, the liquid hazardous waste and the oxidation gas can be adjusted by an external control system.

[0065] As Figure 2 shown in the figure, the thermal plasma torch 9 and the liquid hazardous waste feed sleeve 5 can be hermetically connected, and convenient loading and unloading can be achieved through this hermetic connection, so that the thermal plasma torch 9 is detachably connected to the liquid hazardous waste feed sleeve 5;

[0066] The installation position of the thermal plasma torch 9 is coaxial with the liquid hazardous waste feed sleeve 5, and the plasma outlet 21 at the upper end of the thermal plasma torch 9 is located on the axis; a self-sealing device 22 can also be provided at the interface position of the liquid hazardous waste feed sleeve 5 and the thermal plasma torch 9. When the thermal plasma torch 9 is removed for maintenance, replacement, etc., the opening in the middle of the liquid hazardous waste feed sleeve 5 can be hermetically sealed, and it can also be directly installed and sealed at the opening position in the middle of the liquid hazardous waste feed sleeve 5 through a sealing cover or other devices after the thermal plasma torch 9 is removed.

[0067] As Figure 1As shown, the thermal plasma torch 9 uses air, nitrogen, water vapor, oxygen, inert gas or a mixture thereof as the plasma working fluid (air is used in this embodiment); inside the furnace body, water-cooled walls 10 are provided on the side walls and bottom of the molten pool 1 part, and a heat-insulating refractory material layer 11 is laid on the inner walls of other parts;

[0068] During operation, a stable slag adhering layer 23 is formed between the molten pool 1 and the water-cooled walls 10, which can protect the heat-insulating refractory material layer 11 and the water-cooled walls 10; a heating device is arranged near the position of the slag outlet 8 to prevent the liquid slag near the slag outlet 8 from condensing and blocking the slag outlet 8.

[0069] As Figure 1 shown, after the solid hazardous waste is fed through the solid hazardous waste feed port 4, it falls into the molten pool 1 and is involved in the deep part of the molten pool 1 by the slag circulation 3. Under the agitation of the slag circulation 3, the solid hazardous waste is in full contact with the high-temperature liquid slag in the molten pool 1, accelerating the melting and decomposition of the solid hazardous waste. At the same time, it promotes the locking of the harmful components in the solid hazardous waste by the molten pool 1 (since the melting and decomposition of the solid hazardous waste occur in the deep part of the molten pool 1, the harmful components such as heavy metals and radioactive elements contained in the solid hazardous waste are more easily locked and absorbed by the molten pool 1);

[0070] The liquid hazardous waste is sprayed into the plasma flame 2 from the bottom of the furnace body through the liquid hazardous waste feed sleeve 5 and enters the molten pool 1 together with the plasma flame 2; at the same time, oxidation gas can also be sprayed into the plasma flame 2 from the liquid hazardous waste feed sleeve 5. Under the high-temperature, high-oxidation and high-concentration active group environment of the plasma flame 2, the organic harmful components in the liquid hazardous waste are rapidly oxidized and decomposed by the high temperature and high-concentration active groups of the plasma flame. The decomposed components enter the molten pool 1 together with the plasma flame 2, making the decomposition products of the liquid hazardous waste in full contact with the molten pool 1, promoting the capture of the inorganic harmful components such as heavy metals and radioactive components in the liquid hazardous waste by the molten pool 1. At the same time, the high-temperature environment in the molten pool 1 also provides more high-temperature reaction time for the complete oxidation and decomposition of the liquid hazardous waste to achieve the rapid harmless treatment of the liquid hazardous waste and avoid the secondary generation of harmful substances. The gaseous small molecules generated by the decomposition of the liquid hazardous waste pass through the molten pool 1 in the form of bubbles, enter the gas zone 6, and finally are discharged from the furnace body through the gas outlet 7;

[0071] The gases generated by the decomposition of the solid hazardous waste and the liquid hazardous waste overflow from the molten pool 1 under the action of buoyancy, enter the gas zone 6 above the molten pool 1, and are finally discharged from the gas outlet 7, and the liquid slag is discharged from the slag outlet 8.

[0072] Example 1: Intermittently disposing of solid hazardous waste and liquid hazardous waste, with intermittent slag discharging:

[0073] The method for intermittently disposing of solid hazardous waste and liquid hazardous waste using this thermal plasma furnace includes the following steps:

[0074] Step 1: Seal and connect the hot plasma torch 9 with the liquid hazardous waste feeding sleeve 5;

[0075] Step 2: Feed vitreous slag from the solid hazardous waste feed port 4 so that the vitreous slag accumulates in the furnace body to form a material bed;

[0076] Step 3: Turn on the water cooling switches of the furnace water wall 10 and the liquid hazardous waste feeding sleeve 5, and open the protective gas inlet 15 of the liquid hazardous waste feeding sleeve 5;

[0077] Step 4: Turn on the hot plasma torch 9, spray the plasma flame 2 into the furnace body to melt the vitreous slag, forming a vitreous molten pool 1. Driven continuously by the plasma flame 2, the molten pool 1 forms a stable circulation with the middle rising and the surrounding falling. Adjust the power of the hot plasma torch 9 to keep the temperature of the molten pool 1 at 1500 °C;

[0078] Step 5: If disposing of solid hazardous waste, feed the solid hazardous waste from the solid hazardous waste feed port 4. The solid hazardous waste falls into the molten pool 1 and is involved in the circulation of the molten pool 1. The organic components in the solid hazardous waste decompose into gaseous small molecules at the high temperature of the molten pool 1, and the inorganic components in the solid hazardous waste are quickly melted, and the harmful components are locked by the molten pool 1;

[0079] Step 6: If disposing of liquid hazardous waste, open the oxidation gas inlet 18 and the liquid hazardous waste inlet 17. The oxidation gas and the liquid hazardous waste are respectively sprayed into the plasma flame 2 from the oxidation gas nozzle 14 and the liquid hazardous waste nozzle 13. The organic components in the liquid hazardous waste are quickly oxidized and decomposed in the plasma flame 2, and the inorganic components in the liquid hazardous waste such as heavy metals enter the molten pool 1 along with the plasma flame 2 and are absorbed and locked by the slag in the molten pool 1;

[0080] Step 7: When the liquid level height of the molten pool 1 reaches the set high material level, suspend feeding, open the slag outlet 8, discharge the slag until the liquid level of the molten pool 1 drops to the set low material level, and then close the slag outlet 8;

[0081] Step 8: According to the type of hazardous waste to be disposed, alternately perform the above Steps 5 - 7 to achieve continuous combined disposal of solid and liquid hazardous waste;

[0082] Step 9: After the disposal is completed, stop feeding, close the oxidation gas inlet 18, gradually reduce the power of the hot plasma torch 9, and empty the slag;

[0083] Step 10: Turn off the hot plasma torch 9, close the protective gas inlet 15, and let the system cool naturally.

[0084] In order to ensure the locking effect of vitreous slag on harmful substances such as heavy metals and radioactive substances, during the hazardous waste treatment process, when the silicon content in the hazardous waste is relatively low, materials with a high silicon content (such as glass or vitreous slag) can be introduced through the solid hazardous waste feed inlet 4 during the feeding process to ensure the silicon content in the molten pool 1.

[0085] When the silicon content in the hazardous waste is relatively low, materials with a high silicon content such as glass or vitreous slag can be introduced into the furnace from the solid hazardous waste feeding port during the feeding process to ensure the silicon content in the molten pool 1.

[0086] Example 2: The principle of this example is generally the same as that of Example 1.

[0087] The difference is that this example uses this thermal plasma furnace to simultaneously dispose of solid hazardous waste and liquid hazardous waste with continuous slag discharge, including the following steps:

[0088] Step 1: Seal the connection between the thermal plasma torch 9 and the liquid hazardous waste feeding sleeve 5.

[0089] Step 2: Introduce vitreous slag from the solid hazardous waste feed inlet 4 so that the vitreous slag accumulates in the furnace body to form a material bed.

[0090] Step 3: Open the water cooling switches of the furnace body water wall 10 and the liquid hazardous waste feeding sleeve 5, and open the protective gas inlet 15 of the liquid hazardous waste feeding sleeve 5.

[0091] Step 4: Turn on the thermal plasma torch 9, and the plasma flame 2 is sprayed into the furnace body to melt the vitreous slag, forming a vitreous molten pool 1. Under the continuous pushing of the plasma flame 2, the molten pool 1 forms a stable circulation with the middle rising and the surrounding descending. Adjust the power of the thermal plasma torch 9 to keep the temperature of the molten pool 1 at 1550 °C.

[0092] Step 5: Introduce solid hazardous waste from the solid hazardous waste feed inlet 4. The solid hazardous waste falls into the molten pool 1 and is involved in the circulation of the molten pool 1. The organic components in the solid hazardous waste are decomposed into gaseous small molecules at the high temperature of the molten pool 1, and the inorganic components in the solid hazardous waste are quickly melted, and the harmful components are locked by the molten pool 1.

[0093] Step 6: Open the oxidation gas inlet 18 and the liquid hazardous waste inlet 17. The oxidation gas and the liquid hazardous waste are respectively sprayed into the plasma flame 2 from the oxidation gas nozzle 14 and the liquid hazardous waste nozzle 13. The organic components in the liquid hazardous waste are quickly oxidized and decomposed in the plasma flame 2, and the inorganic components in the liquid hazardous waste such as heavy metals enter the molten pool 1 along with the plasma flame 2 and are absorbed and locked by the slag in the molten pool 1.

[0094] Step 7: When the liquid level height of the molten pool 1 reaches the set value, continue feeding, open the slag outlet 8, control the outflow rate of the slag, so that the amount of the generated liquid slag and the discharged slag maintains a dynamic balance, and the liquid level height of the slag in the furnace remains stable, so as to achieve continuous feeding and slag discharging;

[0095] Step 8: After the treatment is completed, stop feeding, close the oxidation gas inlet 18, gradually reduce the power of the thermal plasma torch 9, and empty the slag;

[0096] Step 9: Turn off the thermal plasma torch 9, close the protective gas inlet 15, and let the system cool naturally.

[0097] The above is only the preferred embodiment of the present invention, and it is not used to limit the present invention. Those skilled in the art can make various modifications or equivalent replacements to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent replacements should also be regarded as falling within the protection scope of the technical solution of the present invention.

Claims

1. A plasma furnace for jointly disposing of solid and liquid hazardous waste, comprising a furnace body. The interior of the furnace body includes a gas zone in the upper part and a molten pool in the lower part. The gas zone is connected to a solid hazardous waste feed inlet and a gas outlet, and the molten pool is connected to a slag outlet. It is characterized in that: A thermal plasma torch and a liquid hazardous waste feed sleeve are provided at the bottom of the furnace body. The thermal plasma torch generates a plasma flame, and the plasma flame passes upward through the bottom of the furnace body and sprays into the molten pool, heating and stirring the molten pool to form a stable slag circulation in the molten pool. The liquid hazardous waste is sprayed into the plasma flame from the bottom of the furnace body through the liquid hazardous waste feed sleeve and enters the molten pool together with the plasma flame. The inner wall of the liquid hazardous waste feed sleeve is provided with a protective gas nozzle, a liquid hazardous waste nozzle and an oxidizing gas nozzle, and the bottom is provided with a protective gas inlet, a liquid hazardous waste inlet and an oxidizing gas inlet. A protective gas channel is connected between the protective gas inlet and the protective gas nozzle, a liquid hazardous waste channel is connected between the liquid hazardous waste inlet and the liquid hazardous waste nozzle, and an oxidizing gas channel is connected between the oxidizing gas inlet and the oxidizing gas nozzle.

2. The plasma furnace for jointly disposing of solid and liquid hazardous wastes according to claim 1, wherein: The thermal plasma torch is located in the middle of the molten pool, and the direction of the slag circulation is upward in the middle of the molten pool and downward around the molten pool.

3. The plasma furnace for jointly disposing of solid and liquid hazardous waste according to claim 1, characterized in that: The liquid hazardous waste feed sleeve is externally connected to the thermal plasma torch, and the plasma flame passes through the liquid hazardous waste feed sleeve and then sprays into the molten pool from the bottom.

4. The plasma furnace for jointly disposing solid and liquid hazardous wastes according to claim 1, characterized in that: The protective gas is nitrogen or an inert gas, and the oxidizing gas is pure oxygen, air or oxygen-enriched air.

5. The plasma furnace for jointly disposing solid and liquid hazardous wastes according to claim 1 or 3, characterized in that: The thermal plasma torch is detachably connected to the liquid hazardous waste feed sleeve.

6. The plasma furnace for jointly treating solid and liquid hazardous wastes according to claim 1, characterized in that: The thermal plasma torch uses air, nitrogen, water vapor, oxygen, an inert gas or a mixture thereof as a plasma working medium.

7. The plasma furnace for jointly disposing of solid and liquid hazardous wastes according to claim 1, characterized in that: Inside the furnace body, water-cooled walls are provided on the side walls and the bottom of the molten pool part, and a heat-insulating refractory material layer is laid on the inner walls of other parts.

8. The plasma furnace for jointly disposing solid and liquid hazardous waste according to claim 1 or 7, characterized in that: A heating device for preventing the condensation of liquid slag near the slag outlet is provided at the position of the slag outlet.

9. A method for using a plasma furnace for jointly treating solid and liquid hazardous waste as described in claim 7, characterized in that, It includes the following steps: Step 1: Connect the thermal plasma torch to the liquid hazardous waste feed sleeve. Step 2: Feed vitreous slag from the solid hazardous waste feed inlet so that the vitreous slag accumulates in the furnace body to form a material bed. Step 3: Turn on the water-cooling switch of the water-cooled wall of the furnace body and the liquid hazardous waste feed sleeve, and turn on the protective gas inlet of the liquid hazardous waste feed sleeve. Step 4: Turn on the thermal plasma torch, and the plasma flame sprays into the furnace body to melt the vitreous slag to form a vitreous molten pool. Under the continuous promotion of the plasma flame, the molten pool forms a stable circulation with rising in the middle and falling around. Step 5: If disposing of solid hazardous waste, feed solid hazardous waste from the solid hazardous waste feed inlet. The solid hazardous waste falls into the molten pool and is involved in the molten pool circulation. The organic components in the solid hazardous waste are decomposed into gaseous small molecules at the high temperature of the molten pool, and the inorganic components in the solid hazardous waste are quickly melted, and the harmful components are locked by the molten pool. Step 6: If disposing of liquid hazardous waste, turn on the oxidizing gas inlet and the liquid hazardous waste inlet. The oxidizing gas and the liquid hazardous waste are respectively sprayed into the plasma flame from the oxidizing gas nozzle and the liquid hazardous waste nozzle. The organic components in the liquid hazardous waste are quickly oxidized and decomposed in the plasma flame, and the inorganic components in the liquid hazardous waste enter the molten pool together with the plasma flame and are absorbed and locked by the slag in the molten pool. Step 7: When the height of the molten pool liquid level reaches the set high material level, suspend the feeding, open the slag outlet, discharge the slag until the molten pool liquid level drops to the set low material level, and then close the slag outlet; Step 8: According to the type of hazardous waste to be treated, alternately perform the above Steps 5-7 to achieve continuous combined treatment of solid and liquid hazardous waste; Step 9: After the treatment is completed, stop the feeding, close the oxidation gas inlet, gradually reduce the power of the thermal plasma torch, and empty the slag; Step 10: Turn off the thermal plasma torch, close the protective gas inlet, and let the system cool naturally.

10. A method for using a plasma furnace for jointly treating solid and liquid hazardous waste as described in claim 7, characterized in that, It includes the following steps: Step 1: Seal and connect the thermal plasma torch with the liquid hazardous waste feeding sleeve; Step 2: Feed the vitreous slag from the solid hazardous waste feed port so that the vitreous slag accumulates in the furnace body to form a material bed; Step 3: Turn on the water cooling switches of the furnace body water-cooled wall and the liquid hazardous waste feeding sleeve, and open the protective gas inlet of the liquid hazardous waste feeding sleeve; Step 4: Turn on the thermal plasma torch, spray the plasma flame into the furnace body, melt the vitreous slag to form a vitreous molten pool, and under the continuous push of the plasma flame, the molten pool forms a stable circulation with the middle rising and the surrounding falling; Step 5: Feed the solid hazardous waste from the solid hazardous waste feed port, the solid hazardous waste falls into the molten pool and is involved in the molten pool circulation. The organic components in the solid hazardous waste are decomposed into gaseous small molecules at the high temperature of the molten pool, the inorganic components in the solid hazardous waste are quickly melted, and the harmful components are locked by the molten pool; Step 6: Open the oxidation gas inlet and the liquid hazardous waste inlet, and the oxidation gas and the liquid hazardous waste are respectively sprayed into the plasma flame from the oxidation gas nozzle and the liquid hazardous waste nozzle. The organic components in the liquid hazardous waste are quickly oxidized and decomposed in the plasma flame, and the inorganic components in the liquid hazardous waste enter the molten pool along with the plasma flame and are absorbed and locked by the slag in the molten pool; Step 7: When the height of the molten pool liquid level reaches the set value, keep feeding, open the slag outlet, control the outflow rate of the slag, so that the amount of liquid slag generated and the amount of slag discharged maintain a dynamic balance, and the height of the molten slag liquid level in the furnace remains stable to achieve continuous feeding and slag discharging; Step 8: After the treatment is completed, stop the feeding, close the oxidation gas inlet, gradually reduce the power of the thermal plasma torch, and empty the slag; Step 9: Turn off the thermal plasma torch, close the protective gas inlet, and let the system cool naturally.

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