JP3181773U - Solvent recovery device - Google Patents

Abstract

A solvent recovery device for efficiently recovering a solvent added to a raw material powder constituting a cemented carbide is provided.
A mixing machine 1 for mixing and drying raw powder of cemented carbide containing a solvent, a vacuum pump 2 for sucking a solvent generated when mixing and drying the raw material powder from the mixing machine, and a vacuum pump A condenser 3 for condensing the solvent sucked by the condenser, and a solvent recovery container 4 for storing the solvent condensed by the condenser. A condenser is provided after the vacuum pump for sucking the solvent, and the solvent sucked by the vacuum pump is condensed by the condenser and collected in a solvent collection container.
[Selection] Figure 1

Description

  The present invention relates to a recovery device that recovers a solvent added to a raw material powder in the process of manufacturing a cemented carbide in which a dispersed phase mainly composed of tungsten carbide (WC) is bonded with a metal phase made of a transition metal such as Co.

  Generally, a cemented carbide in which a dispersed phase mainly composed of tungsten carbide (WC) is bonded with a metal phase made of Co is manufactured through the following steps.

  First, a raw material powder containing WC powder and Co powder, which is a material of a cemented carbide, is stirred and pulverized by, for example, a mill. At this time, a solvent comprising acetone or an alcohol-based dispersion medium is added to the raw material powder, and the mixture is pulverized with stirring in a slurry state. The raw material powder stirred and ground by the mill is made into fine particles having a substantially uniform particle size.

  The raw material powder added with the solvent and stirred and pulverized is put into a mixer and dried while being mixed. The raw material powder dried by the mixer is made into a green compact having a certain shape by a mold apparatus. The green compact is fired at a temperature of about 1300 ° C. to 1400 ° C., thereby forming a cemented carbide used as a material for a cemented carbide tool such as a wear-resistant tool or a mold.

  By the way, the solvent functioning as a dispersion medium is added to the raw material powder pulverized by the mill as described above. This is to prevent the WC particles and the Co particles constituting the binder phase from aggregating to form large particles when the raw material powder is compression molded to form a green compact. When WC particles and Co particles are aggregated in the green compact formed by compressing the raw material powder to form large particles, the quality of the cemented carbide produced by firing this green compact varies. I will let you. As a result, high quality carbide tools cannot be manufactured. Therefore, as described above, a solvent is added to prevent aggregation of WC particles and Co particles constituting the raw material powder.

  Regarding the manufacturing method of this kind of cemented carbide, JP 2006-45601 A (Patent Document 1), JP 2012-24850 A (Patent Document 2), JP 2012-52237 A (Patent Document 3). There is what is described.

JP 2006-45601 A JP 2012-24850 A JP 2012-52237 A

  By the way, when the raw material powder to which the solvent is added is dried by a mixer, the solvent evaporates. This type of solvent can be reused by recovery. In addition, when the solvent is released to the external environment, it contaminates the external environment. Therefore, it is desired to recover the solvent generated when the raw material powder is dried.

  Therefore, an object of the present invention is to provide a solvent recovery apparatus that can efficiently recover a solvent used when manufacturing raw material powder constituting a cemented carbide, for example, a solvent composed of acetone or an alcohol-based dispersion medium. It is to provide.

  Moreover, this invention is providing the collection | recovery apparatus which enables collection | recovery of a solvent, without stopping the drying process of the raw material powder to which the solvent was added.

  The present invention proposed in order to achieve the above-mentioned object is composed of a mixer for mixing and drying a cemented carbide raw material powder to which a solvent is added, and a solvent generated when the raw material powder is mixed and dried. A solvent recovery device comprising: a vacuum pump for sucking the solvent from the mixer; a condenser for condensing the solvent sucked by the vacuum pump; and a solvent recovery container for storing the solvent condensed by the condenser. The condenser is provided in the subsequent stage of the vacuum pump for sucking the water, and the solvent sucked by the vacuum pump is condensed by the condenser and collected in the solvent collection container.

  The present invention further includes a nitrogen gas supply means, and the inside of the mixer and the flow path of the solvent from the mixer to the condenser via the vacuum pump are made a nitrogen atmosphere. At this time, it is desirable that the solvent recovery container has a nitrogen atmosphere.

  In the present invention, it is desirable to provide a filter for filtering the solvent sucked by the vacuum pump between the mixer and the vacuum pump.

  Further, the solvent recovery apparatus according to the present invention switches between a flow path provided with a flow rate adjusting valve and a flow path for directly flowing the solvent flowing out from the filter between the filter and the vacuum pump. An exhaust gas switching valve is provided to switch the flow path according to the flow rate of the solvent flowing out from the filter.

  Furthermore, in the solvent recovery apparatus according to the present invention, the solvent flow path between the mixer and the filter is provided with a flow path cutoff valve for blocking the flow path, and the solvent suction by the vacuum pump is performed. To block.

  In the solvent recovery apparatus according to the present invention, the mixer, the vacuum pump, and the condenser are cooled by cooling water, and the filter is heated by hot water.

  The solvent recovery device according to the present invention is a mixing and drying operation of the raw material powder by the mixer by providing a condenser for aggregating and recovering the solvent generated in the mixer after the suction pump for sucking the solvent from the mixer. Since the solvent can be recovered without stopping the operation, the mixer can be operated continuously.

  Since the flow path of the solvent recovered from the mixer and the mixer is a nitrogen atmosphere, it is possible to recover the solvent by preventing oxidation of the mixed powder and solvent.

  Also, depending on the amount of solvent flowing from the mixer through the filter, the solvent flow path is switched between a flow path that directly circulates to the vacuum pump and a flow path that is provided with a flow control valve. The amount of solvent sucked by the vacuum pump can be kept constant, and the solvent can be recovered stably.

  Furthermore, by providing a flow path shut-off valve in the solvent flow path between the mixer and the filter, a safe solvent recovery operation can be performed.

  Furthermore, the mixer, vacuum pump, and condenser are cooled with cooling water, and the filter is heated with warm water, so that efficient circulation is achieved while achieving stable distribution of solvent transport. Can be realized.

FIG. 1 is a schematic view showing a solvent recovery apparatus according to the present invention.

  Embodiments of a solvent recovery device according to the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the solvent recovery apparatus according to the present invention includes a mixer 1 that dries while mixing a raw material powder to which a solvent composed of acetone or an alcohol-based dispersion medium is added, and a mixed powder by the mixer 1. A vacuum pump 2 for sucking the solvent generated when mixing and drying from the mixer 1, a condenser 3 for condensing the solvent sucked by the vacuum pump 2, and a solvent recovery container for storing the solvent condensed by the condenser 3 4.

  The mixer 1, the vacuum pump 2, the condenser 3, and the solvent recovery container 4 are connected by piping that constitutes a flow path for the solvent generated from the mixer 1. Then, the raw material powder of the cemented carbide added with the solvent is introduced into the mixer 1.

  By the way, the raw material powder introduced into the mixer 1 is a cemented carbide raw material powder mainly composed of WC powder and Co powder, which is stirred and pulverized by a mill into fine particles having a substantially uniform particle size. Yes. This raw material powder is made into a slurry by adding a solvent made of acetone or an alcohol-based dispersion medium. The raw material powder to which the solvent is added to form a slurry is mixed and stirred in the mixer 1 to evaporate the solvent and form fine particles dispersed with each other.

  In addition, wax may be added to the cemented carbide raw material powder introduced into the mixer 1 together with the solvent. The raw material powder to which the wax is added is mixed with the mixer 1 and dried to form fine particles having a wax layer deposited on the surface.

  In addition, the mixer 1 is provided with a solvent outlet 6 through which the solvent vapor generated when the raw material powder to which the solvent is added is mixed and dried is led to the outside. A vacuum pump 2 is connected to the solvent outlet 6 via a pipe. The solvent vapor generated in the mixer 1 is sucked by the vacuum pump 2 through the solvent outlet 6. The solvent vapor sucked by the vacuum pump 2 is led out to a condenser 3 arranged at the rear stage of the vacuum pump 2.

  The solvent vapor introduced into the condenser 3 is condensed by the condenser 3 to be liquid. The liquid solvent is recovered in a container recovery container 4 connected to the condenser 3.

  A main exhaust valve 7 is provided between the solvent outlet 6 and the pipe. The main exhaust valve 7 opens and closes the mixer 1 and controls the outflow of the solvent from the mixer 1.

  The recovery device of the present embodiment includes a nitrogen gas supply mechanism 8, a pipe serving as a solvent flow path from the mixer 1 to the condenser 3 through the vacuum pump 2 from the mixer 1, and a solvent. Nitrogen gas is introduced into the collection container 4 to form a nitrogen atmosphere. By making the nitrogen atmosphere in the mixer 1, the pipe serving as the solvent flow path, and the part through which the solvent including the solvent recovery container 4 flows, the oxidation of the solvent and further the raw material powder in the mixer 1 is prevented, Deterioration of the recovered solvent can be prevented.

  The solvent recovery device is provided with a filter 9 between the mixer 1 and the vacuum pump 2 for filtering the solvent generated from the mixer 1 and sucked by the vacuum pump 2. By providing the filter 9, the solvent from which impurities have been removed can be recovered.

  Between the filter 9 and the vacuum pump 2, there is provided an exhaust switching valve 11 for switching between a flow path for directly flowing the solvent flowing out from the filter 9 to the vacuum pump 2 and a flow path provided with a flow rate adjusting valve 10. By switching the flow path according to the flow rate of the solvent flowing out from the filter 9, the suction amount of the solvent by the vacuum pump 2 can be made constant and the solvent can be recovered stably.

  In the recovery device of the present embodiment, a flow path shutoff valve 12 that shuts off the flow path is provided in the solvent flow path between the mixer 1 and the filter 9. The flow path shut-off valve 12 shuts off the flow path when the flow rate of the solvent flowing through the flow path becomes abnormal and blocks the suction of the solvent by the vacuum pump 2 so as to make the apparatus safe.

  The flow shutoff valve 12 and the vacuum pump 2 are manually operated by operating the operation panel 13.

  Furthermore, cooling water is supplied from a cooling water supply device (not shown) to the mixer 1, the vacuum pump 2, and the condenser 3 constituting the recovery device and cooled. The filter 9 is heated by supplying hot water from a hot water supply device (not shown).

  In addition, the ventilation fan 15 connected to the condenser 3 is installed outside the building 14 where the solvent recovery apparatus according to the present invention is installed, and the recovery apparatus is installed by discharging the solvent leaking from the condenser 3 to the outside. It prevents the leakage of solvent into the building.

  In the solvent recovery apparatus configured as described above, a raw material powder of cemented carbide mainly composed of WC powder and Co powder, which is made into a paste by adding a solvent composed of acetone or an alcohol-based dispersion medium. The raw material powder is introduced into the mixer 1 and dried while being mixed. When the raw material powder to which the solvent is added in the mixer 1 is mixed and dried, the solvent evaporates. The solvent vapor generated in the mixer is sucked into the vacuum pump 2 connected to the mixer 1 and flows out of the mixer 1 through the solvent outlet 6. The vapor of the solvent sucked by the vacuum pump 2 and discharged to the outside of the mixer 1 is supplied to the condenser 3 arranged at the rear stage of the vacuum pump 2, aggregated by the condenser 3 and then stored in the solvent recovery container 4. Collected.

  The solvent recovery apparatus according to the present invention is provided with a condenser 3 for aggregating the solvent and a recovery container 4 for the agglomerated solvent by the condenser 3 at the subsequent stage of the vacuum pump 2 for sucking the solvent flowing out from the mixer 1. Therefore, since the solvent can be recovered even while the mixer 1 is in operation, the mixing and drying of the cemented carbide raw material powder by the mixer 1 can be performed with high efficiency.

  1 Mixer, 2 Vacuum pump, 3 Condenser, 4 Solvent recovery container, 9 Filter, 10 Flow rate adjustment valve, 11 Exhaust gas switching valve, 12 Flow rate cutoff valve

Claims (7)

A mixer for mixing and drying the cemented carbide raw material powder to which a solvent is added;
A vacuum pump for sucking from the mixer the solvent generated when the raw material powder is mixed and dried;
A condenser for condensing the solvent sucked by the vacuum pump;
A solvent recovery container for storing the solvent condensed by the condenser,
The solvent recovery device characterized in that the condenser is provided after the vacuum pump for sucking the solvent, and the solvent sucked by the vacuum pump is condensed by the condenser and recovered in the solvent recovery container. .   The solvent according to claim 1, further comprising a nitrogen gas supply means, wherein the inside of the mixer and the flow path of the solvent from the mixer to the condenser through the vacuum pump are in a nitrogen atmosphere. Recovery device.   2. The solvent recovery apparatus according to claim 1, wherein the solvent recovery container has a nitrogen atmosphere.   The solvent recovery apparatus according to claim 1, wherein a filter for filtering the solvent sucked by the vacuum pump is provided between the mixer and the vacuum pump.   Between the filter and the vacuum pump, there is provided an exhaust switching valve for switching between a flow path for directly passing the exhaust solvent exhausted from the filter to the vacuum pump and a flow path provided with a flow rate adjusting valve, and the exhaust flow is discharged from the filter. 5. The solvent recovery apparatus according to claim 4, wherein the flow path is switched according to the flow rate of the solvent.   The solvent flow path between the mixer and the filter is provided with a flow path shut-off valve that shuts off the flow path, so that the suction of the solvent by the vacuum pump is shut off. 4. The solvent recovery apparatus according to 4.   2. The solvent recovery apparatus according to claim 1, wherein the mixer, the vacuum pump, and the condenser are cooled by cooling water, and the filter is heated by hot water.

Images