Recycling method of tower washing material after spraying of hard alloy mixture

Abstract

The invention discloses a recovery processing method of a tower washing material after spraying of a hard alloy mixture, and relates to the technical field of hard alloys, a ball mill is used for ball milling, and various components in the tower washing material are uniformly mixed; filtering the slurry through a stainless steel filter screen to remove impurities in the tower washing material; carrying out vacuum drying treatment on the slurry to remove moisture in the tower washing material; the dried material is subjected to dewaxing, oxygen reduction and high-temperature calcination treatment through a dewaxing furnace, paraffin in the tower washing material is removed, meanwhile, hydrogen and oxygen reduction can be carried out, the oxygen content in the tower washing material is reduced, and residual oleic acid and other non-metal impurities in the tower washing material can be combusted and removed at high temperature through high-temperature calcination. And detecting the treated tower washing material to obtain a qualified mixture. According to the method, independent treatment equipment is not needed, operation can be conducted through existing equipment such as a ball mill, a vacuum dryer, a vibration screening machine and a high-temperature dewaxing furnace, and the method has the advantages of being simple in process, easy to operate and the like.

Description

Technical Field

[0001] The invention relates to the technical field of cemented carbide, and in particular to a method for processing materials washed out of a spray tower after spray granulation of a cemented carbide mixture. Background Art

[0002] The production process of cemented carbide generally includes batching, ball milling, drying, waxing, granulation, pressing, dewaxing, sintering and other processes. Now more and more cemented carbide manufacturers have changed the original drying, waxing and granulation process to advanced spray drying production process in order to improve product quality. During the spray drying process of the mixture, a layer of material will adhere to the wall of the spray tower. According to the process requirements, the spray tower will be cleaned regularly or when the brand is changed. During the cleaning process, because the mixture contains wax, the adhesion is relatively strong and it is not easy to clean. Therefore, in order to facilitate cleaning, a certain proportion of phosphoric acid will be added to the cleaning water tank. The washed powder will be soaked in water for a long time, which will cause the oxygen content and some impurities to exceed the standard and cannot be used as a mixture again. The traditional method is usually to clean out these tower washing materials, put them in an oven for drying, and then treat them as waste. As waste, its value will be reduced and the utilization rate of raw materials will also be reduced.

[0003] In summary, in order to improve the use value of tower washing materials, after a long period of experiments, a new processing method for tower washing materials is now provided. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a method for processing tower wash materials produced after spray drying of a cemented carbide mixture. The tower wash materials can be processed into qualified materials by utilizing existing production equipment and new processing technology without investing in new production equipment.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical scheme: a method for recycling tower washing materials after spraying of cemented carbide mixture, characterized in that: the process is as follows: the tower washing materials in the cleaning water tank are cleaned out, precipitated for a certain period of time, and then the water in the upper layer is discharged, and then the tower washing materials are loaded into a ball mill, and appropriate amounts of alloy balls and alcohol are added for ball milling. After a certain period of ball milling, the various components in the tower washing materials are evenly mixed to form a slurry, and the slurry is filtered by a screen to remove impurities, and precipitated for a certain period of time, and then the mixed liquid of alcohol and water in the upper layer is discharged, and then the slurry is loaded into a dryer for drying, and the stirring rod is set to rotate forward and reverse, and the stirring is stopped after drying for a certain period of time, and vacuum drying is performed, and then vacuum cooling is performed. After cooling, it is sieved to obtain a dry material, and the dry material is loaded into a dewaxing furnace for hydrogen dewaxing, reduction, and high-temperature calcination to obtain a qualified mixture.

[0006] Preferably, the ball mill is a tilting ball mill.

[0007] Preferably, the dryer is a double Z-type vacuum dryer.

[0008] Preferably, the sieve is a stainless steel sieve of 250 mesh or above.

[0009] Preferably, the sedimentation time of the slurry is 4-12 hours.

[0010] Preferably, during ball milling, the ball-to-material ratio is 1.0-1.5, the amount of alcohol added is 200-250 ml / KG, and the ball milling time is 6-10 hours.

[0011] Preferably, the forward and reverse stirring time is set to 30 minutes, and the stirring is stopped after drying for 1 hour, and vacuum drying is performed, and the drying is terminated when the vacuum degree reaches 0.9 MPa.

[0012] Preferably, after cooling, the tower wash material is vibrated and sieved using an 80-mesh stainless steel screen.

[0013] Preferably, when the tower washing material is subjected to dewaxing and calcining treatment, the equipment used is a dewaxing equipment having a hydrogen dewaxing function and capable of withstanding a high temperature of 1000°C.

[0014] Preferably, the dewaxing temperature, time and hydrogen flow rate are set as follows: first heating to 180°C for 150 minutes, keeping warm for 60 minutes, and the hydrogen flow rate is 2.0-2.6m 3 / h; then heat to 260℃ for 180 minutes, keep warm for 60 minutes, and the hydrogen flow rate is 2.0-2.6m 3 / h; then heated to 360°C for 600 minutes, with a hydrogen flow rate of 2.0-2.6m 3 / h; then heated to 450°C for 150 minutes, with a hydrogen flow rate of 2.0-2.6m 3 / h, keep warm for 60 minutes; finally heat to 900℃ for 480 minutes, with hydrogen flow rate of 2.0-2.6m 3 / h; keep warm for 180 minutes, hydrogen flow rate is 2.0-2.6m 3 / h; after the insulation is completed, the material is naturally cooled and taken out of the furnace to obtain qualified tower washing material.

[0015] Compared with the prior art, the present invention has the following advantages and effects: The present invention utilizes a ball mill to evenly mix various components in the tower washing material; the slurry is filtered through a stainless steel filter to remove impurities in the tower washing material; the slurry is vacuum dried to remove moisture in the tower washing material; the dried material is dewaxed, oxygen reduced and high-temperature calcined in a dewaxing furnace to remove the paraffin in the tower washing material, and hydrogen and oxygen reduction can be performed to reduce the oxygen content in the tower washing material. The high-temperature calcination can burn and remove oleic acid and other non-metallic impurities remaining in the tower washing material at high temperature. The treated tower washing material is tested to become a qualified mixed material.

[0016] The present invention does not require investment in separate processing equipment, and can be operated using existing ball mills, vacuum dryers, vibrating sieving machines, high-temperature wax removal furnaces and other equipment, and has the advantages of simple process and simple operation. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention are clearly and completely described below. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0018] Example 1.

[0019] The present invention provides a technical solution: a method for recycling tower washing materials after spraying of cemented carbide mixture, the process is as follows: cleaning out the tower washing materials in the cleaning water tank, settling for a certain period of time, then discharging the water in the upper layer, then loading the tower washing materials into a tilting ball mill, adding an appropriate amount of alloy balls and alcohol for ball milling, through a certain period of ball milling, making the various components in the tower washing materials evenly mixed to form slurry, using a screen to filter the slurry to remove impurities, the screen is a stainless steel screen of 250 mesh or above, settling for a certain period of time, then discharging the alcohol and water in the upper layer. Mix the liquids, then load the slurry into a double Z-type vacuum dryer for drying. Set the stirring rod to rotate forward and reverse, and set the forward and reverse stirring time to 30 minutes. After drying for 1 hour, stop stirring the stirring rod and perform vacuum drying. When the vacuum degree reaches 0.9 MPa, the drying is terminated and vacuum cooling is performed. After the cooling is completed, the tower washing material is vibrated and sieved using an 80-mesh stainless steel screen to obtain a dry material. The dry material is loaded into a dewaxing furnace for hydrogen dewaxing, reduction, and high-temperature calcination. The equipment used is a dewaxing equipment with a hydrogen dewaxing function and capable of withstanding a high temperature of 1000°C to obtain a qualified mixed material.

[0020] Example 2.

[0021] In this embodiment, a method for recycling tower washing materials after spraying a cemented carbide mixture is provided, and the steps are as follows: Step 1, load 400KG of tower washing material into a tilting ball mill for ball milling, add appropriate amount of alloy balls and alcohol for ball milling, control the ball-to-material ratio at 1.0-1.5, add 200-250ml / KG of alcohol, and control the ball milling time at 6-10 hours. Ball mill for a certain period of time to allow the tower washing material to form a slurry.

[0022] Step 2: After the ball milling is completed, install a stainless steel screen with a mesh size of 250 or above on the vibrating screen to filter the slurry and remove impurities.

[0023] Step 3, precipitate the slurry for 4-12 hours, then extract the mixed liquid of alcohol and water in the upper layer, and then put the slurry into a Z-type vacuum dryer, and dry and sieve it according to conventional operating methods.

[0024] Step 4: Pack the dried tower wash material into stainless steel trays and then into a high-temperature dewaxing furnace for dewaxing. The dewaxing temperature, time and hydrogen flow rate are set as follows: first heat to 180°C for 150 minutes, keep warm for 60 minutes, and the hydrogen flow rate is 2.0-2.6m 3 / h; then heat to 260℃ for 180 minutes, keep warm for 60 minutes, and the hydrogen flow rate is 2.0-2.6m 3 / h; then heated to 360°C for 600 minutes, with a hydrogen flow rate of 2.0-2.6m 3 / h; then heated to 450°C for 150 minutes, with a hydrogen flow rate of 2.0-2.6m 3 / h, keep warm for 60 minutes; finally heat to 900℃ for 480 minutes, with hydrogen flow rate of 2.0-2.6m 3 / h; keep warm for 180 minutes, hydrogen flow rate is 2.0-2.6m 3 / h; after the insulation is completed, the material is naturally cooled and taken out of the furnace to obtain qualified tower washing material.

[0025] Although embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and concepts of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for recycling tower washing materials after spraying of cemented carbide mixture, characterized in that: The process is as follows: the tower washing material is loaded into a ball mill, and an appropriate amount of alloy balls and alcohol are added for ball milling. After a certain period of ball milling, the various components in the tower washing material are evenly mixed to form a slurry. The slurry is filtered with a screen to remove impurities. After settling for a certain period of time, the mixed liquid of alcohol and water on the upper layer is discharged, and then the slurry is loaded into a dryer for drying. The stirring rod is set to rotate forward and reverse. After drying for a certain period of time, the stirring is stopped, and vacuum drying is performed. After vacuum cooling, it is sieved after cooling to obtain a dry material, and the dry material is loaded into a dewaxing furnace for hydrogen dewaxing, reduction, and high-temperature calcination to obtain a qualified mixed material.

2. The method for recycling the tower washing material after the cemented carbide mixture spraying according to claim 1 is characterized in that: The ball mill is a tiltable ball mill.

3. The method for recycling the tower washing material after the cemented carbide mixture spraying according to claim 1 is characterized in that: The dryer is a double Z-type vacuum dryer.

4. The method for recycling the tower washing material after the cemented carbide mixture spraying according to claim 1 is characterized in that: The sieve is a stainless steel sieve of 250 mesh or above.

5. The method for recycling tower washing materials after spraying of cemented carbide mixture according to claim 1, characterized in that: The settling time of the slurry is 4-12 hours.

6. The method for recycling tower washing materials after spraying of cemented carbide mixture according to claim 1, characterized in that: During ball milling, the ball-to-material ratio is 1.0-1.5, the amount of alcohol added is 200-250 ml / KG, and the ball milling time is 6-10 hours.

7. The method for recycling tower washing materials after spraying of cemented carbide mixture according to claim 1, characterized in that: The forward and reverse stirring time was set to 30 minutes. After drying for 1 hour, stirring was stopped and vacuum drying was performed. Drying was completed when the vacuum degree reached 0.9 MPa.

8. The method for recycling tower washing materials after spraying of cemented carbide mixture according to claim 1, characterized in that: After cooling, the tower wash material is vibrated and sieved using an 80-mesh stainless steel screen.

9. The method for recycling tower washing materials after spraying of cemented carbide mixture according to claim 1, characterized in that: When the tower washing material is dewaxed and calcined, the equipment used is a dewaxing equipment with hydrogen dewaxing function and capable of withstanding a high temperature of 1000°C.

10. The method for recycling tower washing materials after spraying of cemented carbide mixture according to claim 1, characterized in that: The dewaxing temperature, time and hydrogen flow rate are set as follows: first, heat to 180°C for 150 minutes, keep warm for 60 minutes, and the hydrogen flow rate is 2.0-2.6m 3 / h; then heat to 260℃ for 180 minutes, keep warm for 60 minutes, and the hydrogen flow rate is 2.0-2.6m 3 / h; then heated to 360°C for 600 minutes, with a hydrogen flow rate of 2.0-2.6m 3 / h; then heated to 450°C for 150 minutes, with a hydrogen flow rate of 2.0-2.6m 3 / h, keep warm for 60 minutes; finally heat to 900℃ for 480 minutes, with hydrogen flow rate of 2.0-2.6m 3 / h; keep warm for 180 minutes, hydrogen flow rate is 2.0-2.6m 3 / h; after the insulation is completed, the material is naturally cooled and taken out of the furnace to obtain qualified tower washing material.