JP2001246215A - Method and apparatus for treating fine particles of fatty acid in exhaust gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently collect fine particles of fatty acid in exhaust gas containing scattered fatty acid generated at a time of the extrusion molding/ processing of a resin by an easy technique to safely remove them without causing the generation of a fire after collection. SOLUTION: Exhaust gas containing scattered fatty acid is heated to a temperature higher than the melting point of the fatty acid with a heater 4 to form fine particles of liquefied fatty acid and steam whose temperature is higher than the melting point of the fatty acid is sprayed on these fine particles to make moisture adhere to the surfaces of the fine particles and a large number pf the fine particles are permitted to adhere to each other by the adhesion force of moisture to grow to form fatty acid mist of large particles, and the exhaust gas containing this fatty acid mist is passed through a filter 6 to cause the fatty acid mist to adhere on the filter to remove the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for removing fatty acid fine particles in a gas generated during extrusion molding and processing of a resin.

[0002]

2. Description of the Related Art During extrusion molding and processing of a synthetic resin, additives (fatty acids and the like) incorporated in the resin to improve the moldability are volatilized or scattered together with a mist containing a resin component degraded by heating. As a result, gas containing dust is generated around the extruder, which deteriorates the working environment.

Therefore, conventionally, the generated gas is forcibly sucked by a fan from a hood together with the surrounding air and discharged into the atmosphere. However, the fatty acid fine particles solidify below 60 ° C. The exhaust gas temperature is reduced to less than 60 ° C. by mixing with ambient air, heat radiation in the discharge duct path, etc., and as a result, white smoke is blown out of the chimney, which is an environmental and sanitary problem.

[0004]

In order to solve this problem, conventionally, an exhaust gas containing fatty acid fine particles is removed by passing the exhaust gas containing a fatty acid fine particle through a water washing device (scrubber) or an electric dust collector. Released into the atmosphere.

However, when a water scrubber (scrubber) is used, the removal efficiency is very low at around 10%, and when an electrostatic precipitator is used, the collection efficiency is good, but on the other hand, fatty acids are not removed. There is a problem that the dust contained in the dust collector accumulates and causes a fire.

[0006]

An object of the present invention is to remove fatty acid fine particles from exhaust gas by a simple method and efficiently, and to remove fatty acid fine particles from exhaust gas safely without causing a fire after the collection. A method and an apparatus therefor.

[0007]

The method of the present invention for treating fatty acid fine particles in exhaust gas comprises heating the exhaust gas containing scattered fatty acids generated during extrusion molding and processing of the resin at a temperature higher than the melting point of the fatty acid. Water is attached to the surface of the fine particles by spraying water vapor at a temperature higher than the melting point of the fatty acid onto the fine particles, and a large number of the fine particles are combined and grown by the adhesive force of the water to produce a fatty acid of a large particle. The method is characterized in that the exhaust gas containing the fatty acid mist is passed through a filter to remove the fatty acid mist by adhering to the filter.

Further, the apparatus for treating fatty acid fine particles in exhaust gas according to the present invention is arranged in a fatty acid removing apparatus connected to an exhaust duct for exhaust gas containing scattered fatty acids generated during extrusion molding and processing of a resin in the direction of flow of the exhaust gas. A heater, a steam atomizer, and a filter are provided, and the exhaust gas from the exhaust duct is heated by the heater at a temperature higher than the melting point of the fatty acid to convert the fatty acid into liquid fine particles. Next, the exhaust gas is higher than the melting point of the fatty acid. A steam at a temperature is sprayed from the steam atomizer to attach moisture to the surface of the fatty acid, the plurality of fine particles are combined by the adhesive force of the moisture to grow into a fatty acid mist of large particles, and then the exhaust gas is passed through the filter. In this way, the fatty acid mist is attached to the filter so that the exhaust gas can be exhausted as the exhaust gas from which the fatty acid has been removed.

Further, in the apparatus of the present invention, a drain pipe for discharging the liquid fatty acid which is not captured by the filter and flows down is provided at the bottom of the apparatus.

Further, in the apparatus of the present invention, means for supplying hot water having a temperature higher than the melting point of the fatty acid so as to reach a liquid level at which the filter is submerged, in order to wash the fatty acid attached to the filter. Means for discharging the fatty acid liquid dissolved in the warm water and accumulated in the upper layer of the warm water to the outside of the apparatus.

Further, in the apparatus of the present invention, a plurality of fatty acid removing devices are arranged in parallel in the exhaust duct, and when one of the fatty acid removing devices is performing a fatty acid mist removing operation, the remaining fatty acid removing device is provided. The operation is sequentially switched between the fatty acid removal operation and the washing operation so that the fatty acid adhering to the filter is washed.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. Exhaust gas G containing scattered fatty acids generated during extrusion molding and processing of the resin is guided to the fatty acid removing device 2 by the exhaust duct 1 of FIG. The device 2 includes a heater 4, a steam atomizer 5, and a metal filter 6 such as a demister in the exhaust gas flow path main body 3 in the flow direction of the exhaust gas.

Exhaust gas from the exhaust duct 1 is heated by the heater 4 to a temperature higher than the melting point of the fatty acid, for example, 60 ° C. or higher, so that the fatty acid becomes liquid fine particles. In addition, fatty acids include stearic acid, palmitic acid, and myristic acid. The melting points of stearic acid are 70.1 ° C, the melting point of palmitic acid is 63 ° C, and the melting point of myristic acid is 53.8 ° C. The melting point drops below 60 ° C. in each case due to the inclusion. For example, the melting point of stearic acid containing impurities is 58 ° C.

The fatty acid fine particles are sprayed with steam at a temperature of 60 ° C. or more from the next steam sprayer 5 to adhere moisture to the surface, and a plurality of fine particles are combined by the adhesive force of the water and grow to form large particles. Mist.

When the exhaust gas passes through a metal filter 6 such as a demister, fatty acid mist is collected. Since the fatty acid mist is formed as large particles that have grown, the fatty acid mist is collected by the filter 6. It is easy and sufficient. The exhaust gas from which the fatty acids have been removed is sent to a chimney or the like by a blower 7,
Dissipated into the atmosphere.

The fatty acid mist collected by the filter 6 gradually solidifies by lowering the temperature to below 60 ° C. and solidifies on the filter, but the fatty acid mist not captured by the filter is removed by the apparatus. From the drain pipe 8 to the appropriate processing section for fatty acids.

After the fatty acid mist in the exhaust gas has been removed for a required time, it is necessary to remove the fatty acid adhering to the filter. For this purpose, as shown in FIG. 2, hot water 13 is supplied so as to have a liquid level in which the filter 6 is immersed in the apparatus, and hot water having a temperature higher than the melting point of the fatty acid is used.

As a result, the solid fatty acid adhering to the filter 6 is dissolved by the warm water, and the dissolved fatty acid 14 has a specific gravity smaller than that of the warm water 13 and thus accumulates in the upper layer of the warm water. It is discharged to appropriate disposal unit of the fatty acids by opening the opening and closing valve V ₁ of the overflow pipe 9 provided with a fatty acid 14 collected in the upper layer on the side of the device.

There are various types of hot water supply means. One example is hot water supply means from the drain pipe 8. In that case, connected via an on-off valve V ₂ hot water supply pipe 10 to the drain pipe 8, to the drain pipe 8 is provided an opening and closing valve V _3, V _4.

[0020] By thus, upon removal operation of the fatty acid mist is also closed off valve V ₁ of the overflow pipe is closed off valve V ₂ of the hot water supply pipe on-off valve V _3, V ₄ of the drain pipe is left open.

During the washing operation of the filter, the open / close valve V ₃ of the drain pipe is opened and V ₄ is closed, and the open / close valve V ₂ of the hot water supply pipe is opened to supply hot water until the filter sinks into the apparatus. in addition, the on-off valve V ₁ of the overflow pipe is opened.

Since the exhaust gas is sent from the exhaust duct 1 continuously for 24 hours, the operation of the fatty acid removing device cannot be stopped. To cope with this, in the present invention through the damper means V ₅ serving respectively opening and closing means to supply header 11a fatty removal device 2 connected to the exhaust duct 1 connected to the plurality based on parallel, also fatty acid removal device 2 Exhaust port is exhaust header 1
1b, and the header is connected to the blower 7 by one exhaust pipe 12.
Connect to

By doing so, only the opening / closing damper of a certain fatty acid removing device is closed, and the opening / closing dampers of the remaining fatty acid removing device are opened, and while the fatty acid mist removing operation is performed by the fatty acid removing device of the open damper, the opening / closing damper is closed. In the fatty acid removing device of the damper, the cleaning operation of the filter is performed, and the fatty acid mist removing operation of the fatty acid removing device and the cleaning operation of the filter are sequentially switched, whereby the fatty acid mist removing operation can be continuously performed.

At this time, the number of fatty acid removing devices is not two,
It is desirable to have three or more. If there are two units, each fatty acid removing device must be able to handle the maximum air volume of exhaust gas from the exhaust duct, and each fatty acid removing device is large,
Although a large capacity is required, if the number of fatty acid removing devices is, for example, 6, the remaining 5 units perform the removing operation while one unit performs the cleaning operation. Only 1/5 of the maximum air volume of the device, and there is an advantage that the size and capacity of each device can be reduced.

Further, the flow path main body 3 is formed as a U-shaped bend pipe as shown in the figure, and a coarse filter is provided on one gas suction pipe side and a dense filter is provided on the other discharge pipe side. The fatty acid mist can be more sufficiently removed by disposing

[0026]

According to the present invention, fatty acids can be easily and sufficiently removed from exhaust gas containing fatty acid fine particles generated during resin extrusion molding and processing by a heater, a steam atomizer, and a filter. Fatty acid removal efficiency is much higher than when a washing device is used.Furthermore, there is almost no risk of fire occurring when using an electrostatic precipitator, and a device with a relatively simple structure and low manufacturing cost is required. Can be provided.

Further, according to the present invention, it is not necessary to use any chemicals, so that fatty acids can be safely removed without damaging the working environment.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view showing an operation state of removing fatty acid mist by an embodiment of the apparatus according to the present invention.

FIG. 2 is a longitudinal sectional front view showing a cleaning operation state of a filter according to an embodiment of the apparatus according to the present invention.

FIG. 3 is a perspective view showing an embodiment of the present invention in which a plurality of fatty acid removing devices are provided in parallel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Exhaust duct 2 Fatty acid remover 3 Flow path main body 4 Heater 5 Steam sprayer 6 Filter 7 Blower 8 Drain pipe 9 Overflow pipe 10 Hot water supply pipe 11a Air supply header 11b Exhaust header 12 Exhaust pipe 13 Hot water 14 Melted fatty acid

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naobu Motozawa 3-4-2, Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Paper Mills Co., Ltd. (72) Hiroyuki Toge 4--11-34, Higashishinagawa, Shinagawa-ku, Tokyo No. Inside the Toyo Seisakusho Co., Ltd. (72) Inventor Muneshi Yamaguchi 4--11-34 Higashi-Shinagawa, Shinagawa-ku, Tokyo Inside the Toyo Seisakusho Co., Ltd. (72) Kinichi Odashima 4-1-134, Higashi-Shinagawa, Shinagawa-ku, Tokyo No. Inside the Toyo Seisakusho Co., Ltd. (72) Inventor Hisashi Yanaka 4-11-34, Higashishinagawa, Shinagawa-ku, Tokyo F-term inside the Toyo Seisakusho 4D032 AC07 AC39 BA03 BA06 BB05 CA01 CA10 DA10 4D058 JA12 JB03 JB24 KC04 LA01 MA12 MA51 QA01 QA03 QA05 QA11 RA02 RA15 SA15 UA01 UA25

Claims (5)

[Claims] 1. Exhaust gas containing scattered fatty acids generated during extrusion molding and processing of a resin is heated at a temperature higher than the melting point of the fatty acids to form liquefied fatty acid fine particles.
By spraying water vapor at a temperature higher than the melting point of the fatty acid, water is attached to the surface of the fine particles, and a large number of fine particles are combined and grown by the adhesive force of the water to form a fatty acid mist of large particles. A method for treating fatty acid fine particles in exhaust gas, wherein the fatty acid mist is attached to the filter and removed by passing exhaust gas containing the gas through a filter. 2. A heater, a steam atomizer, and a filter are sequentially provided in a flow direction of exhaust gas in a fatty acid removing device connected to an exhaust duct of exhaust gas containing scattered fatty acids generated during extrusion molding and processing of a resin. The exhaust gas is heated by the heater at a temperature higher than the melting point of the fatty acid to convert the fatty acid into liquid fine particles, and then a steam having a temperature higher than the melting point of the fatty acid is sprayed on the exhaust gas from the steam atomizer to the surface of the fatty acid. By adhering moisture, the plurality of fine particles are combined with each other by the adhesive force of the moisture to grow into a fatty acid mist of large particles, and then the exhaust gas is passed through the filter to attach the fatty acid mist to the filter, whereby the fatty acid is removed. Equipment for treating fatty acid fine particles in exhaust gas discharged as removed exhaust gas. 3. An apparatus for treating fatty acid fine particles in exhaust gas according to claim 2, wherein a drain pipe for discharging the liquid fatty acid that is not captured by the filter and flows down is provided at the bottom of the apparatus. 4. The apparatus according to claim 2, wherein hot water having a temperature higher than the melting point of the fatty acid is supplied so as to reach a liquid level at which the filter is submerged, in order to wash fatty acids attached to the filter. An apparatus for discharging fatty acid liquid dissolved in hot water and remaining in an upper layer of the warm water outside the apparatus. 5. The apparatus according to claim 2, wherein a plurality of fatty acid removing devices are connected in parallel to the exhaust duct, and when one of the fatty acid removing devices is performing a fatty acid mist removing operation, the remaining fatty acid removing device is connected to the exhaust duct. The apparatus for treating fatty acid fine particles in exhaust gas, wherein the fatty acid removing apparatus is sequentially switched between a fatty acid removing operation and a washing operation such that the fatty acid removing apparatus is operated to wash the fatty acid adhering to the filter.