JP2002285178A - Air stream drying equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air stream drying equipment of high drying efficiency causing no local melting of waste plastics and affording waste plastics of a proper moisture content irrespective of the variation of the moisture content of waste plastics to be fed. SOLUTION: This air stream drying equipment has the following scheme: a helical wire material 1 is set in a hot air transport pipe 20 so as to uniformize the temperature of hot air; a moisture meter is set up on a quantitative feeder 30 to measure the moisture content of waste plastics, based on the measurement, the feed of the waster plastics is controlled; a returning transport pipe 3 for returning hot air or the like used for drying to the dryer body 40 is set up to guarantee the air flow in the dryer body even when the quantity of hot air is small, thereby improving drying efficiency; further, a 2nd moisture meter for measuring the moisture content of waste plastics after dried, the measurements are put to feedback to guarantee the quality of the waste plastics after dried.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flash drying device for hydrated materials, and more particularly to a flash drying device for waste plastics.

[0002]

2. Description of the Related Art FIG. 4 is a configuration diagram schematically showing the configuration of a conventional flash drying facility. In FIG. 4, the hot air generator 1
The hot air generated at 0 is guided to the dryer main body 40 by the hot air transport pipe 20. Further, waste plastic to be dried (hereinafter referred to as waste plastic) is cut out by a predetermined amount from the quantitative feeder 30 and supplied into the hot air transport pipe 20 by the supply screw 31 and transported to the dryer main body 40 by hot air. Is done. Then, in the dryer main body 40, the waste plastic is heated while being swirled by the hot air, and a part of the water contained in the waste plastic is separated as steam.

Further, waste plastic dried in the dryer main body 40 (hereinafter referred to as dried waste plastic), hot air used for drying, and steam generated during the drying (hereinafter, a mixture of the three are dried and mixed). The waste is guided to the dry matter separator 60 via the dry mixture transport pipe 50, and the dried waste plastic as a solid component and other gas components (hot air supplied for drying and hot air generated during the drying). Water vapor).

[0004] The separated solid matter (dry waste plastic) is supplied to a mixed layer 70. On the other hand, the gas content (hot air supplied for drying and water vapor generated during the drying) is passed through a gas content transport pipe 80 to the dry matter collector 9.
After being guided to zero and removing dust, it is released into the atmosphere.

[0005] Further, after the solid component (dry waste plastic) charged into the mixing layer 70 is discharged from the mixing tank, the solid component is passed through a predetermined granulation step to be used as fuel or blast furnace raw material (reducing agent). It's being used.

A thermocouple 41 is provided in the dryer main body 40, and the hot air generator 10 is controlled based on the measurement result of the thermocouple 41.

[0007]

When waste plastic is used as a fuel or a blast furnace raw material (reducing agent) (hereinafter the two are collectively referred to as a blast furnace raw material), a choke is used from the viewpoint of transportability and combustibility. It is necessary to granulate in a shape and a granule,
If the water content of the waste plastic exceeds 10%, granulation cannot be performed because heat for melting and solidifying the plastic is used for evaporating water, and so the material is dried before granulation to reduce the water content to 10%.
% Or less.

[0008] However, the conventional flash dryer which controls only the temperature of the airflow in the dryer body has the following problems.

1) Since the water content of the waste plastic is not constant, the waste plastic to be dealt with has passed while responding to the fluctuation of the water content. For this reason, it is necessary to spray water on the over-dried waste plastic to prevent the waste plastic from being over-dried with low moisture content and easily melting in the granulator and causing problems such as blockage. In the case of waste water or high-moisture waste, it was discharged undried to produce ungranulated materials.

[0010] 2) Further, since the temperature distribution of the airflow has a considerable variation, the waste plastic is melted at places where the temperature is locally high, and the waste plastic adheres to the thermocouple. For this reason, the control has been difficult due to a significant change in the measurement temperature.

3) Further, since the waste plastic is dried while colliding the waste plastic with a wall surface or the like, the waste plastic is transported by pneumatic transport, so that a certain speed or more is required. Therefore, even if the processing amount is small, the air volume cannot be reduced, and when the processing amount is small, the drying efficiency is low in inverse proportion to the processing amount.

An object of the present invention is to solve the above problems and to provide a flash drying apparatus capable of obtaining waste plastic having an appropriate water content without lowering the drying efficiency.

[0013]

The flash drying equipment of the present invention for solving such a problem is as follows. [1] Hot-air generating means for generating hot air, dry-substance supplying means for supplying a dry-substance to be dried to a hot-air transport pipe, a dryer body for drying the dry substance by the hot air, The dried object, a dried material separating means for separating the dried object to be dried from the dried mixture containing the hot air and the generated steam provided for drying, and the drying after the dried object to be dried is separated. An atmosphere discharging unit that releases separated air containing the supplied hot air and generated steam to the atmosphere, a hot air transport pipe that transports the hot air from the hot air generating means to the main body of the dryer, and the dry mixture from the main body of the dryer. And a separated air transport pipe for transporting the separated air from the dried substance separating means to the atmospheric discharge section, wherein the hot air transport is performed. Mix hot air into the pipe. Alternatively, a temperature equalizing means for turning is arranged. [2] Hot-air generating means for generating hot air, dry-substance supply means for supplying a dry-substance to be dried to a hot-air transport pipe, a dryer body for drying the dry-substance by the hot air, The dried object, a dried material separating means for separating the dried object to be dried from the dried mixture containing the hot air and the generated steam provided for drying, and the drying after the dried object to be dried is separated. An atmosphere discharging unit that releases separated air containing the supplied hot air and generated steam to the atmosphere, a hot air transport pipe that transports the hot air from the hot air generating means to the main body of the dryer, and the dry mixture from the main body of the dryer. A dry mixture transport pipe for transporting the dried product to the dried product separating means, and a separated air transport pipe for transporting the separated air from the dried product separating means to the atmospheric discharge section, wherein the drying target is Upstream of the material supply means or In the drying object supply means,
A water content measuring means for measuring a water content contained in the object to be dried, and a supply amount control for controlling an amount of the object to be dried to be supplied to the hot air transport pipe based on a measurement result of the water content measuring means. It is characterized by having means. [3] A hot air generating means for generating hot air, a drying object supply means for supplying a drying object to be dried to a hot air transport pipe, a dryer body for drying the drying object by the hot air, The dried object, a dried material separating means for separating the dried object to be dried from the dried mixture containing the hot air and the generated steam provided for drying, and the drying after the dried object to be dried is separated. An atmosphere discharging unit that releases separated air containing the supplied hot air and generated steam to the atmosphere, a hot air transport pipe that transports the hot air from the hot air generating unit to the dryer main body, and a drying mixture from the dryer main body. A dry mixture transport pipe for transporting the dried mixture to the dried product separating means, and a separated air transport pipe for transporting the separated air from the dried product separating means to the atmospheric discharge section, wherein the dry mixing Drying in the body transport tube A return transport pipe for returning a part of the mixture to the hot air transport pipe is provided. [4] In the above [3], a hot air generating means for generating hot air, a dry matter supply means for supplying a dry matter to be dried to a hot air transport pipe, and drying for drying the dry matter with the hot air. The main body of the machine, the dried object to be dried, the dried object separating means for separating the dried object to be dried from the dried mixture containing the hot air and the generated steam subjected to drying, and the dried object to be dried is separated. An air discharge unit that discharges the separated air containing the hot air and generated steam after drying to the atmosphere, a hot air transport pipe that transports the hot air from the hot air generating means to the main body of the dryer, and the dryer. In a flash drying apparatus having a dry mixture transport pipe for transporting the dry mixture from the main body to the dry substance separation means, and a separation air transport pipe for transporting the separated air from the dry substance separation means to the atmospheric discharge section. And the dry matter Downstream of the separating means or in the dried matter separating means, a moisture content measuring means for measuring the moisture content of the dried matter after the separated air is separated is installed, and the moisture content measuring means measures the moisture content. On the basis of the result, a return amount control means for controlling an amount of returning a part of the dry mixture in the dry mixture transport pipe to the hot air transport pipe is provided. [5] The method according to any one of [1] to [4], wherein the object to be dried is waste plastic. [6] In the above item [5], the dried object to be dried is used as a fuel or a blast furnace raw material.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] FIG. 1 is a configuration diagram schematically showing the configuration of an embodiment of a flash drying facility according to the present invention. In FIG. 1, the same portions as those in the conventional diagram described in FIG. 3 are denoted by the same reference numerals, and a part of the description will be omitted.

In FIG. 1, a spiral wire 1 is arranged in a hot air transport pipe 20. The spiral wire 1 mixes or swirls the hot air to make the temperature of the hot air in the hot air transport pipe 20 uniform. Therefore, since the variation in the temperature distribution of the hot air in the dryer main body 40 is eliminated, the waste plastic is melted in a locally high temperature portion, and the molten waste plastic adheres to the thermocouple 41, and the measured temperature is significantly increased. The conventional problem that the control (one or both of the temperature and the air volume) of the hot air generator 10 becomes difficult is solved.

Further, a waste plastic moisture meter 2 for measuring the water content of the waste plastic is provided in a casing 32 of the supply screw 31. Therefore, it is possible to control the supply amount of the quantitative supply device 30 based on the measurement result of the waste plastic moisture meter 2. That is, the supply amount is decreased in the case of waste plastic having a high water content, and the supply amount is increased in the case of waste plastic having a low water content.

The temperature equalizing means of the present invention is not limited to a spiral wire, and a spiral wing may be arranged, or a plate-shaped or massive flow resistor may be arranged. A turbulent or swirling flow may be generated in the flow resistor. [Embodiment 2] Fig. 2 is a configuration diagram schematically showing the configuration of another embodiment of the flash drying equipment according to the present invention. In FIG. 2, the same parts as those in the conventional drawing described in FIG. 3 are denoted by the same reference numerals, and a part of the description is omitted.

In FIG. 2, a hot air transport pipe 20 and a dry mixture transport pipe 50 are connected by a return transport pipe 3, and a return damper 4 for controlling a return amount is installed in the return transport pipe 3. Therefore, when the amount of waste plastic supplied from the fixed quantity supply device 30 is small, a part of the dry mixture can be supplied again to the dryer main body 40 via the return transport pipe 3. , The hot air generator 10 according to the amount of the waste plastic.
Even if the amount of hot air transported from the dryer is reduced, the flow rate of waste plastic transport in the dryer main body 40 is guaranteed. That is, even if the amount of waste plastic is small, the amount of hot air generated by the hot air generating furnace can be reduced, and the drying efficiency does not deteriorate even when the amount of waste plastic is small.

Further, in the casing 72 of the discharge screw 71 disposed below the mixing tank 70, a dry waste plastic moisture meter 5 for measuring the water content of the waste waste plastic is installed.
Therefore, based on the measurement result of the dried waste plastic moisture meter 5, the opening degree of the return damper 4 can be adjusted so that the moisture content of the dried waste plastic becomes, for example, 5% or less. That is, as the moisture content of the dried waste plastic is higher, the opening degree of the return damper 4 is increased, and the amount of repeatedly dried plastic is increased.

It should be noted that, based on the measurement result of the dried waste plastic moisture meter 5, the amount of waste plastic supplied from the quantitative feeder 30 is controlled, or the temperature or the amount of hot air generated by the hot air generator 10 is controlled. Good. [Embodiment 3] Fig. 3 is a configuration diagram schematically showing a configuration of another embodiment of the flash drying equipment according to the present invention. The invention shown in FIG. 3 includes the spiral wire 1 and the waste plastic moisture meter 2 shown in the first embodiment, and the return transport pipe 3, the return damper 4, and the dry waste plastic moisture meter 5 shown in the second embodiment. It is provided. Therefore, the functions and effects shown in the first embodiment and the second embodiment are achieved.

[0021]

According to the flash drying equipment of the present invention described above, the following remarkable effects can be obtained.

1) Since the temperature equalizing means is disposed in the hot air transport pipe, the temperature of the hot air is equalized, and the local melting of the waste plastic and the accompanying attachment of the waste plastic to the thermocouple are eliminated. The temperature control is stabilized and the accuracy of the temperature control is improved. Therefore, the quality of the dried waste plastic is improved.

2) Since the moisture meter for measuring the water content of the waste plastic is installed in the quantitative feeder, the supply amount of the waste plastic can be controlled based on the measurement result of the moisture meter. The quality of plastic is improved.

3) The hot air transport pipe on the upstream side of the dryer body and the dry mixture transport pipe on the downstream side of the dryer body are connected by the return transport pipe, and the dry mixture can be returned to the dryer body again. Therefore, even when the amount of hot air generated in the hot air generating furnace is small, the amount of air in the dryer main body can be guaranteed, so that it is not necessary to generate unnecessary hot air, and drying efficiency is improved.

4) Since a moisture meter for measuring the water content of the dried waste plastic is installed in the mixing tank, it is possible to adjust the amount of the dried mixture to be returned to the main body of the dryer based on the measurement result of the moisture meter. As a result, the quality of the dried waste plastic is improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing a configuration of an embodiment of a flash drying facility according to the present invention.

FIG. 2 is a configuration diagram schematically showing a configuration of another embodiment of the flash drying equipment according to the present invention.

FIG. 3 is a configuration diagram schematically showing the configuration of another embodiment of the flash drying equipment according to the present invention.

FIG. 4 is a configuration diagram schematically showing the configuration of a conventional flash drying facility.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spiral wire 2 Waste plastic moisture meter 3 Return transport pipe 4 Return damper 5 Dry waste plastic moisture meter 10 Hot air generator 20 Hot air transport pipe 30 Quantitative feeder 31 Supply screw 32 Casing 40 Dryer main body 41 Thermocouple 50 Dry mixing Body transport pipe 60 Dry matter separator 70 Mixing layer 80 Gas transport pipe 90 Dry matter dust collector

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ichiro Kuriyama 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Inside Nihon Kokan Co., Ltd. (72) Inventor Kazuhiro Teratsuji 1-1-2, Marunouchi, Chiyoda-ku, Tokyo F-term (reference) in Nippon Kokan Co., Ltd. 3L113 AA07 AB02 AB03 AC03 AC40 AC45 AC46 AC50 AC52 AC54 AC60 AC61 AC64 AC83 AC86 BA01 CA02 CB23 DA01 DA24 4H015 AA02 AA17 AB01 BA09 BB03 CB01 4K012 BE01 BE09

Claims (6)

[Claims] 1. A hot air generating means for generating hot air, a drying object supply means for supplying a drying object to be dried to a hot air transport pipe, a dryer body for drying the drying object by the hot air, A dried material to be dried, a dried material separating means for separating the dried material to be dried from the dry mixture containing the hot air and the generated steam subjected to drying, and after the dried material to be dried is separated, An air discharging unit that discharges the separated air containing the hot air and the generated steam used for drying to the atmosphere; a hot air transport pipe that transports the hot air from the hot air generating unit to the dryer main body; and the drying from the dryer main body. A flash drying apparatus having a dry mixture transport pipe for transporting the mixture to the dry substance separating means, and a separation air transport pipe for transporting the separated air from the dry substance separating means to the atmospheric discharge unit, In the hot air transport pipe, Flash drying equipment, characterized by arranging the temperature-equalizing means for mixing or swirling wind. 2. A hot air generating means for generating hot air, a dry matter supply means for supplying a dry matter to be dried to a hot air transport pipe, a dryer body for drying the dry matter by the hot air, A dried material to be dried, a dried material separating means for separating the dried material to be dried from the dry mixture containing the hot air and the generated steam subjected to drying, and after the dried material to be dried is separated, An air discharging unit that discharges the separated air containing the hot air and the generated steam used for drying to the atmosphere; a hot air transport pipe that transports the hot air from the hot air generating unit to the dryer main body; and the drying from the dryer main body. A flash drying apparatus having a dry mixture transport pipe for transporting the mixture to the dry substance separating means, and a separation air transport pipe for transporting the separated air from the dry substance separating means to the atmospheric discharge unit, Dry matter supply means Upstream or in the dried matter supply means, a moisture content measuring means for measuring the moisture content of the dried matter is installed, and based on the measurement result of the moisture content measuring means, the hot air transport pipe of the dried matter is provided. Flash drying equipment comprising a supply amount control means for controlling an amount supplied to the apparatus. 3. A hot air generating means for generating hot air, a drying object supply means for supplying a drying object to be dried to a hot air transport pipe, a dryer body for drying the drying object by the hot air, A dried material to be dried, a dried material separating means for separating the dried material to be dried from the dry mixture containing the hot air and the generated steam subjected to drying, and after the dried material to be dried is separated, An air discharging unit that discharges the separated air containing the hot air and the generated steam used for drying to the atmosphere, a hot air transport pipe that transports the hot air from the hot air generating unit to the dryer main body, and the drying from the dryer main body. A flash drying apparatus having a dry mixture transport pipe for transporting the mixture to the dry substance separating means, and a separation air transport pipe for transporting the separated air from the dry substance separating means to the atmospheric discharge unit, Dry mixture transport tube Flash drying equipment, wherein a portion of said dry mixture that installed the return transport pipe for returning the heated air transport pipe. 4. A hot air generating means for generating hot air, a dry matter supply means for supplying a dry matter to be dried to a hot air transport pipe, a dryer body for drying the dry matter by the hot air, A dried material to be dried, a dried material separating means for separating the dried material to be dried from the dry mixture containing the hot air and the generated steam subjected to drying, and after the dried material to be dried is separated, An air discharging unit that discharges the separated air containing the hot air and the generated steam used for drying to the atmosphere; a hot air transport pipe that transports the hot air from the hot air generating unit to the dryer main body; and the drying from the dryer main body. A flash drying apparatus having a dry mixture transport pipe for transporting the mixture to the dry substance separating means, and a separation air transport pipe for transporting the separated air from the dry substance separating means to the atmospheric discharge unit, For dry matter separation means Or downstream of the dried matter separating means, a moisture content measuring means for measuring the water content of the dried matter after the separated air is separated is installed, and the measurement result of the moisture content measuring means is provided. 4. The flash drying equipment according to claim 3, further comprising a return amount control means for controlling an amount of the part of the dry mixture in the dry mixture transport pipe that is returned to the hot air transport pipe. 5. The flash drying equipment according to claim 1, wherein the object to be dried is waste plastic. 6. The flash drying equipment according to claim 5, wherein the dried material to be dried is used as fuel or blast furnace raw material.