JPH081075Y2 - Volatile scatter remover - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The present invention is a device for producing plastic films such as polypropylene, polyester, nylon, etc., particularly a device for removing volatile scattered substances such as oligomers and oil mist, which is applied to the stretching device. It is about.

(Prior Art) Conventionally, the most general method for producing a stretched film is to circulate hot air whose temperature is controlled to preheat, stretch, heat set and cool the film.

However, this method has a drawback in that sublimates, oil mist and the like scatter in the hot air during operation and adhere to the film being manufactured. In addition,
Examples of the scattered substances include oligomers during polyester stretching and additive evaporation components during polypropylene stretching.

By the way, in order to remove these scattered matters, conventionally, for example, as shown in JP-A-58-65731, polyester oligomers are passed through the oxidation catalyst layer at a normal operating temperature without further heating the hot air. A method of burning off is disclosed. This method is characterized in that a noble metal such as platinum is supported on the oxidation catalyst layer and burned at a relatively low temperature of 200 to 250 ° C.

(Problems to be Solved by the Invention) However, even if the above-mentioned conventional method is applied to stretching of a polypropylene film, the hot air temperature is usually as low as 160 ° C., so that a sufficient combustion effect cannot be obtained. In addition, the performance was rapidly deteriorated by the catalyst poison of oil mist generated from the additive, which was not practical.

On the other hand, for example, Japanese Unexamined Patent Publication (Kokai) No. 60-97829 discloses a method for removing oligomers and oil mist by using an adsorbent such as activated carbon, alumina and clay, and it is said that activated carbon pellets are particularly effective. However, general adsorbents such as activated carbon have so-called selectivity, which limits the substances that can be adsorbed, and has the characteristic that the adsorption capacity decreases as the adsorption temperature rises. For example, the stretching temperature of the polyester film is 230 to 250 ° C., which is the temperature at which the adsorbed substance is usually desorbed from the activated carbon, and it is extremely inefficient to carry out the adsorption operation of the oligomer at this temperature, and a large amount of activated carbon I need. In addition, oil mists are generally difficult to adsorb and tend to break through early.

Further, the adsorbent which has reached the breakthrough, it is necessary to desorb the adsorbed substance by the desorption operation, but for this purpose, it is necessary to desorb at a temperature 150 to 200 ° C. higher than the adsorption temperature,
Generally, it is a form of entrusting the regeneration treatment to the adsorbent manufacturer.

The present invention provides a solution to the conventional problems such as the limitation of the hot air temperature range and the catalyst poison in the conventional oxidation catalyst, the selectivity of the adsorbent in the adsorbent, the lowering of the adsorption capacity in a high temperature atmosphere, and the short life. It is an object of the present invention to provide a volatile scattering material removing device for a plastic film stretching device that can solve the problems and stably remove volatile scattering materials in hot air in various film stretching processes.

(Means for Solving the Problems) Therefore, the present invention has a circulation path of hot air for heating a film, a radiation conversion ability, and is partitioned by a ceramic body having no air permeability, and an internal heat source is Invisible directly, a high temperature combustion chamber that constitutes a so-called optically closed space, a heat exchanger, and a portion of the circulating hot air is introduced from the circulation path into the high temperature combustion chamber via the heat exchanger, It is composed of an inlet duct and an outlet duct for circulating hot air so as to return to the same hot air circulation path via the same heat exchanger, and this is a means for solving the problem.

(Function) A part of the hot air that heats the film circulating in the hot air circulation path is partitioned by a ceramic body that has a radiant conversion ability (it is heated by the radiant heat and emits radiant heat) and has no air permeability. Moreover, the internal heat source (electric heater, etc.) is introduced through a heat exchanger into a high temperature combustion chamber that constitutes a so-called optically closed space, which cannot be seen directly from the outside, and is again passed through the heat exchanger. The hot air is returned to the circulation path, and the volatile scattered substances or components in the hot air can be completely burned and removed in the high temperature combustion chamber.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a detailed cross-sectional view of a high temperature combustion chamber of one embodiment, which is a main part of the present invention, and FIG. 2 is the high temperature combustion chamber. And the temperature profiles before and after that, showing that the high temperature confinement effect is different depending on the presence or absence of the ceramic bodies 103a and 103b having the radiation converting ability and having no air permeability.

Now, the basic structure of the high temperature combustion chamber 100 shown in FIG. 1 has a cylindrical or square-shaped radiant conversion ability, and a non-breathable ceramic body 102, 103a, 103b and a flat radiant conversion ability, and has a ventilation characteristic. It is composed of an electric heater 101 in a space surrounded by a non-conductive ceramic body 104, and constitutes a so-called optically closed space in which the electric heater 101 inside cannot be directly seen from the outside. Then, by introducing the air 203a containing volatile scattered substances such as oligomers into the high temperature combustion chamber 100, the scattered substances can be efficiently burned and decomposed.

Next, based on the principle shown in FIG. 1 and FIG. 2, a high temperature combustion chamber 10 made of a ceramic body having a radiation converting ability and having no air permeability.
An example in which the heat exchanger 105 is combined with 0 and is connected to a stretched film manufacturing apparatus is shown in FIG. In FIG. 3, 200 is the hot air circulation device of the stretched film manufacturing apparatus, and 150 is the high temperature combustion chamber 1.
This is a device for removing volatile scattered substances, which comprises 00 and a heat exchanger 105.

The hot air circulation device unit 200 of the stretched film manufacturing apparatus,
A fan 201 for circulating the hot air 203, a motor 202 for driving the fan 201, and a duct 20 serving as a passage for the hot air 203.
4. A nozzle box 205 for jetting the hot air 203 to blow it onto the film 206, a clip traveling mechanism 207 for pulling the film 206 left and right, and a heater 208 for heating the hot air 203.

On the other hand, the volatile scattered matter removing device 150 includes an inlet duct 106 for receiving a part 203a of the circulating hot air 203 and a heat exchanger 10.
5 、 Ceramic body with radiation conversion ability and no air permeability 102-10
4, outlet duct 1 of high temperature combustion chamber 100 consisting of electric heater 101
It is composed of 07.

Next, the operation of the embodiment shown in FIG. 3 configured as described above will be described. Volatile scattered matters such as oligomers volatilized and scattered from the film 206 are introduced together with the hot air 203a into the inlet duct 10.
After passing 6 through the heat exchanger 105, a ceramic body made of ceramic or the like having a radiation conversion ability and having no air permeability 102 to 1
04, and the high temperature combustion chamber 100 composed of the electric heater 101,
Complete combustion is achieved by passing through the path shown by the arrow in FIG.

Then, the combustion gas generated by this combustion is returned to the heat exchanger 105.
At the same time, the air 203a containing oligomers or the like before combustion is preheated, and at the same time, the combustion gas itself is cooled and the outlet duct 107
It is discharged to the vicinity of the heater 208 inside the hot air circulation device 200 via the above. In this embodiment, the electric heater 102 is used as the heat source for the high temperature combustion chamber 100, but the same effect can be obtained by introducing the fuel gas such as propane.

(Effect of the Invention) According to the present invention as described in detail above, since the volatile scattered substances in the hot air are burned and removed, the concentration of the volatile scattered substances in the hot air in the hot air circulation path can be significantly reduced, and Compared with the conventional method, it is possible to stably remove the volatile scattered substances in the circulating hot air, and it is possible to produce a high quality film with few defects at an extremely low cost.

[Brief description of drawings]

FIG. 1 is a detailed cross-sectional view of a high temperature combustion chamber according to an embodiment of the present invention, FIG. 2 is a diagram showing the temperature profile of the high temperature combustion chamber and the temperature profiles before and after the same, and FIG. 3 is a high temperature combustion chamber of FIG. It is sectional drawing of the volatile scattered material removal apparatus containing the hot air circulation apparatus part of the stretched film manufacturing apparatus which consists of a combination of heat exchangers. Explanation of the main parts of the figure 100 …… High temperature combustion chamber, 101 …… Electric heaters 102,103a, 103b, 104 …… Ceramic body that has radiant conversion capability and is not breathable 103 …… Part of hot air, 105 …… Heat Exchanger 106 …… Inlet duct, 107 …… Outlet duct 150 …… Volatile scatter removal device 200 …… Hot air circulation unit, 201 …… Fan 202 …… Motor, 203 …… Hot air 204 …… Circulation path, 205 ...... Nozzle box 206 …… Film, 208 …… Heater

Claims (1)

[Scope of utility model registration request] 1. A circulation path of hot air for heating a film, which has a radiation conversion ability and is partitioned by a ceramic body having no air permeability,
In addition, the internal heat source cannot be directly seen from the outside, a high temperature combustion chamber that constitutes a so-called optically closed space, a heat exchanger, and the high temperature combustion chamber, a part of the circulating hot air is circulated from the circulation path. A volatile scattered matter removing device comprising an inlet and an outlet duct for circulating hot air introduced through a heat exchanger and returning to the hot air circulation path through the heat exchanger again.