JPH01171808A - Controller for moisture of plastic waste earth - Google Patents

Abstract

PURPOSE:To reduce the amount of scatter in moisture of plastic waste earth, by measuring the moisture and the weight of fragments of dried plate-like waste earth, processing the measured values on real time and adding water thereto. CONSTITUTION:Mud slurry 1 is dehydrated in a dehydrator 11 to be plate-like waste earth 2. It becomes dried plate-like waste earth 3 in a storage chamber 12 and then fragments 4 in a crusher 13. The weight of the fragments 4 is measured with a weigher 24 immediately after being crushed in the crusher 13 or on a conveying device 14. The moisture of the fragments 4 is measured on real time with a moisture meter 23 and measured values are entered into a processing unit 25 together with the values of weight. The processing unit 25 processes such values periodically, derives the average moisture of the fragments from the values of moisture and weight a controlled unit of fragments and the difference between the aimed moisture and the average moisture. If the average moisture is less than the aimed moisture, the processing unit sends an instruction to the dehydrator 27 to make it to add water. Then, the fragments have the aimed moisture and such fragments are conveyed into a deaerator-kneader 15 to be plastic waste earth 5, where the amount of scatter in moisture of the plastic waste earth 5 is + or -0.5%.

Description

[Detailed description of the invention] B1 Purpose of the invention [Industrial application field] This invention relates to a moisture control device for plastic clay used as a raw material for ceramics.

Specifically, the present invention relates to a clay moisture control device aimed at reducing variations in moisture content of plastic clay.

[Prior Art] In the process of producing plastic clay, slurry is dehydrated using a dewatering device such as a filter press to form a plate-shaped clay, and the clay is naturally dried in a storage room. The dried plate-shaped clay is crushed into small pieces for feeding into a pug mill, and water is added to adjust the moisture content. The crushed material and water are degassed and kneaded using a vacuum mixer such as a pug mill to form plastic clay.

Conventionally, adjustment of the moisture value of plastic clay to a target value is performed in a plate-shaped clay that has been air-dried in a process prior to feeding into a pug mill. In other words, judgments are made based on experience, such as the degree of dents when a part of the plate-shaped clay that has been left to air dry in a storage room for more than a day is pressed with one's fingers, or the state of the cracks when the plate-shaped clay is split. Moisture values are measured using samples taken from lots selected by pushing the material into the soil and estimating the moisture value from the depth of the push.

However, the plate-shaped clay that has been left to dry naturally in the storage room for more than a day,
Although the variation in the moisture value of each part of the lot is smaller compared to plate-shaped clay dehydrated using a filter press, etc., the variation is large in relation to the requirements, and a considerable number of steps are required to improve accuracy. The sample had to be measured, which required a lot of man-hours.

Moreover, it is difficult to sample the central part of ten or more plate-shaped clay blocks due to the location, and it is not easy to accurately capture the entire lot and measure the moisture content.

In addition, phyto-backing of plastic clay is also carried out by measuring the amount of plastic clay, but this method is difficult to obtain properly after the results are obtained.

[Problems to be Solved by the Invention] If the moisture value of this plastic clay varies greatly from its target value, cracks, deformation, dimensional defects, etc. may occur during the molding, drying, firing, etc. processes of manufacturing the product. This can lead to product defects.

Therefore, it is an object of the present invention to provide a plastic clay moisture control device that measures the moisture content of crushed materials immediately before being fed into a pug mill and adjusts the moisture content of the plastic clay to a target value with small variations. do.

1. Structure of the invention [Means for solving the problem] The present invention provides a method of crushing and crushing the plate-shaped clay 2 in the step of creating a plastic clay for ceramics from the slurry 1 through the plate-shaped clay 2. A crushing device 13 that transports the crushed materials, a conveying device 14 that conveys the crushed materials, a level adjustment device 22 that adjusts the level of the crushed materials on the conveying device 14, and a moisture content of the crushed materials being transported by the conveying device 14. Moisture meter 23 for measuring value and weight
And a weighing scale 24, and a calculation processing bag for inputting the moisture value and weight measurement value in real time! 25, and a water addition amount control device 27 that adds water based on the difference between the plastic clay moisture value and the target value in response to a command from the arithmetic processing unit 25. be.

[Function] The function of the present invention will be explained with reference to FIG. 1, which shows the relationship between the flow of materials and the device for processing materials in the plastic clay moisture control device of the present invention. The slurry 1 is made into plate-shaped clay 2 in a dewatering device 11, dried plate-shaped clay 3 in a storage room 12, and crushed into small pieces 4 in a crushing device 13.

The level adjustment device is for adjusting the height of the crushed material layer on the conveying device 14. The weight of the shredded material is measured immediately after being shredded by the shredding device 13 or on a weighing scale 2 on the conveying device.
Measured by 4. The moisture value of the crushed material is measured in real time by a moisture meter 23 and is input to the processing unit 25 in the same way as the weight. The arithmetic processing unit 25 calculates the average moisture value of the crushed material in a certain control unit from the moisture value and weight of the crushed material measured at regular intervals, and if there is a shortage of the target moisture value, it issues a command to the hydration IIIal device 27. , water adding device 28
Water is added from In this way, the crushed material has a moisture content of the target value and is fed into the deaeration/kneading device 15 to be made into the plastic clay 5.

[Example] An example of the present invention is shown.

[Example 1] Sludge 1 is dehydrated using a filter press to form plate-shaped clay 2. The weight of one sheet of this plate-shaped clay 2 is 30 kg, and 10 pieces is about 15 pieces. The plate-shaped clay 2 is stored in a storage room to form a dried plate-shaped clay 3. A lot is selected based on judgment based on experience such as holding down a part of this dried plate-shaped clay 3 with one's fingers, splitting it, pushing a spring-loaded needle into the plate-shaped clay, and estimating the moisture content from the depth of the push. The dried plate-shaped clay 3 of the lot selected in this way is sent to the crushing device 13, and the average length is 10 m.
It is considered as crushed material of small pieces of about 4. Crushed material 4 is pug mill 1
5 onto a belt conveyor 14.

The presence or absence of crushing eJI4 on the belt conveyor 14 is detected by sensor 2.
It is determined by 1. A level adjustment device 22 is provided for adjusting the height of the crushed material 4 delivered on the belt conveyor 14. In this way, a certain amount of crushed material 4 is continuously conveyed to the pug mill 15 on the belt conveyor 14. The moisture value and the weight per unit area are measured using a moisture meter 23 (for example, an infrared moisture needle) and a weight scale 24 (for example, a conveyor scale) installed directly below the moisture meter. In other words, sampling is performed for each unit length of the belt conveyor 14 (the encoder is pulsed), the moisture value at sampling point i is XIJ, and the moisture meter 2 is
3 is 3, the weight of the crushed material 4 is WI, and the sampling period (k pulses) is T 1 from the belt conveyor speed.
1 @ 0, control is performed every 9 samplings, and the target moisture value is set to 0. The weight of the crushed material for each control unit is W and the amount of water added is -x, and the correction coefficient is determined at the adjustment stage.

These measured values are input to the arithmetic processing unit 22 in real time. The frequency of control is performed at a constant cycle of tT@·O, and can be adjusted by a sensor 26 (for example, an encoder) installed at the rear of the belt conveyor 14.

On the other hand, the arithmetic processing device 25 calculates the average moisture value of the crushed material in a certain control unit from the input measurement value, calculates the difference from the target moisture value, and instructs the water addition amount control device 27 to Water is added from the spray part 28 to the crushed material 4 that has been fed into the pug mill 15 from the belt conveyor 14. The clay is degassed and kneaded in these pug mills to obtain plastic clay.

That is, the amount of water added per unit time is Δu=u/QT. However, there is also a method of determining the moisture content for each sampling.

The arithmetic processing unit 25 determines the timing at which the crushed material 4 is introduced into the pug mill 15 using an encoder 26 or the like, and instructs the water addition amount control device to output the dripping amount ΔU.

When the variation in the moisture content of the plastic clay thus obtained was measured, the variation was ±0.5% with respect to the target moisture content of 23.0%.

In addition to the crushing device used in this example, a Ni-Goo can also be used.

Further, a plurality of moisture meters 23 can be installed in the width direction of the belt conveyor 14.

[Example 2] As in Example 1, the crushed materials 4 are made into small pieces of about 10 mm on average, and before being conveyed to the belt conveyor 14, the weight of the crushed materials is weighed using a weighing scale 24, and the crushed materials are sent onto the belt conveyor 14. . The presence or absence of crushed material 4 on the belt conveyor 14 is determined by a sensor 21. A level adjustment device 22 is provided for adjusting the height of the crushed material 4 delivered on the belt conveyor 14. In this way, a certain amount of crushed material 4 is continuously conveyed to the pug mill 15 on the belt conveyor 14. The moisture value is measured with a moisture meter 23 (infrared moisture meter). The measurement values are input to the arithmetic processing unit 25 in real time, etc., in the same manner as in the first embodiment.

In addition, in either of Examples 1 and 2, the actual moisture value of the plastic clay is measured, it is determined whether it is within the range of variation of the target moisture value, and the result is input to the arithmetic processing device. You can also measure the stability of your water level by applying Phytovac.

C1 Effects of the Invention As explained above, according to the present invention, the water content and weight of the crushed dried plate-shaped clay are measured immediately before degassing and kneading,
By performing calculation processing and adding water in real time, we were able to reduce the variation in the moisture content of the plastic clay.

The use of this excellent plastic clay contributed to the efficient manufacture of products.

[Brief explanation of the drawing]

FIG. 1 shows the flow of the mechanism of the plastic clay moisture control device of the present invention. 1...Sludge 2...Plat-shaped clay 3...Dry plate-shaped clay 4...Crushed material 5...Plastic clay

Claims (1)

[Claims] In the process of creating plastic clay for ceramics from slurry 1 through plate-shaped clay 2, a crushing device 13 that crushes the plate-shaped clay 2 into crushed materials, and a conveying device 14 that transports the crushed materials , a level adjustment device 22 that adjusts the level of the crushed material 4 on the conveying device 14 , a scale 24 that weighs the weight of the crushed material 4 , and a moisture value of the crushed material 4 being conveyed by the conveying device 14 . a moisture meter 23 that measures the moisture content, an arithmetic processing unit 25 that inputs the measured moisture value and weight in real time, and an arithmetic processing unit 25 that calculates the amount of water to be added based on the difference between the plastic clay moisture value and the target value based on a command from the arithmetic processing unit 25. A plastic clay moisture control device for ceramics, comprising a water addition amount control device 27 for adding water.