DD219267A1 - METHOD FOR DRYING CERAMIC ARTICLES - Google Patents

Abstract

The invention relates to a process for the drying of ceramic articles. It is applicable to the industry of ceramics, especially in the leather hard and dry-drying range of ceramic articles. The aim of the invention is to carry out the drying with room air without additional heat input and with speed energy, thereby reducing energy consumption and by uniform drying lower the Rohbruchanteil and the equipment cost. The essence of the invention is that the entire article surface with Raumlauft, which has a temperature of 20-30 C and a relative humidity to about 70%, is blown from below and above by means of blowing and in 30-50 minutes the articles of about 22% moisture dried to about 1.5% residual moisture.

Description

Title of the invention. ·· ... Process for drying ceramic articles

Field of application of the invention

The invention relates to sin process for drying of ceramic articles in the field of hard leather and Wsißtrocknung within the ceramic industry.

Characteristic of the known technical solutions

Ceramic articles · must be subjected to drying before firing. This is necessary so that the abandoned kiln can leave the kiln in high quality. .

To speed up the drying process, the process stage is carried out using heat and at a temperature in the range of about 40 ⁰ C to 120 ⁰ C. However, this process requires for evaporation or evaporation of the article moisture large amounts of heat And extends over the field of leather hard and white drying. The drying process is determined by the type of raw materials used, the article form, the external drying conditions and the condition and design of the drying device. However, the multiplicity of the fiinflußgrößen also leads to insufficient quality of the dried articles, which is associated with deformation and cracking, even if they are not sufficiently coordinated.

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Conventional. Troubleshooting are in the Literaturstelien "technology of fine ceramics" German publishing house for primary industry, "technology of coarse ceramics"'3d. 2 and 3 publishing house for building, Berlin, '' Trocknungstechnik ¹ · vol. 1 and 2 Springer publishing house Berlin ,. "The drying" publisher Sauarländer set out.

Object of the invention. '.

The aim of the invention is to significantly reduce energy consumption by reducing the drying technology using room air as the drying agent, to reduce the proportion of raw fractions and to lower the equipment ratio.

Explanation of the essence of the invention.

According to the conventional method of convection drying, the drying intensity is determined by the external conditions drying agent temperature, relative desiccant and desiccant speed. 'In the field of leather hard drying about 40 ⁰ C, it is primarily important to run the drying process with a balanced vote of the three mentioned Wirkgrößen to each other anderanfalls the drying is associated with quality losses and it comes to the deformation and in the course of cracking the Items. In contrast, the Waißtr-ocknung is carried out at higher temperatures of about 120 ⁰ C.

According to the invention, the drying effect is achieved with the use of only one drying condition, namely the drying medium rate. Namely room air with dsm existing climate is sucked as desiccant by a conveyor organ, and passed through pipe with blower until just before the article · .Ober'Düsen aar blowing device leaves the desiccant with high exit

speed, which results in a large heat transfer coefficient at the article impact bar, the piping system. The entrained by the Trsibstrahl the nozzles. Room air is called after combination of both streams as desiccant.

A large number of die openings in the article area indicate that the drying agent on the article surface meets the guarantee that a high drying intensity and an even removal of the fibers and a tension-free drainage over the entire surface of the article takes place. The drying dnsness is increased by changing the distance of the nozzles to the article and thus the impact speed. Also by applying tailpipes with variable distance from the nozzle and different motive jet quantity of mass transfer can be influenced «An exhaust air bites promotes the spent drying agent from the dryer into the atmosphere or returns it as circulating air in the process. The transport of the articles through the dryer is done by a conventional device, which promotes the articles from the task to the discharge, with simultaneous drying. In contrast, the entire blowing device is stationary, but locally adjustable, housed in the dryer rack. As a drying agent is

According to the invention, room air with a temperature of 20-30 C and a relative humidity of up to approx. 70 % is used. With stated room climate and high desiccant speed can be dried after detachment of the articles of a metal or plaster mold with an initial moisture content of about 22 % within 30 - 50 minutes to about »1.5 % Final Fattentsgahalt.

embodiment

The invention will be explained in more detail with reference to an embodiment. , , ,

In the accompanying drawings is shown :.

Fig. 1 Schematic diagram of the drying with \ · Kaitluftanblasung (top view)

Fig. 2 section of Tellartransportes with blowing device

Through the dryer 4 are conveyor chains 3 "with swings 2, which have sine great free and level surface, towards 3.1 continuously performed over the entire dryer height" on the swings 2 ceramic Article 1 next to each other are sold "for the purpose is drying ^ Room air 14 sucked in via pipe section 9 from the gasifier IQ and conveyed via .Rohrung 8 with "opening 22 and blowing device 5 to the article 1. In der'Rohrleitung 8 with blowing device 5 nozzle holes 6 in the vicinity of the article 6 at a small distance from each other 'arranged. After leaving the Treibstrahlas 21 from the Düssnöffnung 6 to the pipe -8, catch pipes 7 are arranged · The pipe 8 with catching pipe 7 are installed in the dryer 4 above and below the swings 2 occupied by Article 1. Pipe with catching pipe 7 of the blowing device 5 are displaced in the vertical direction 20, if necessary. The conveyed through die.Rohrleitung 8 from the blower 10 room air 14 enters via 'nozzle holes 5 as blowing jets 21 at high Kerngeschwindig- speed in the catch tube 7, wherein room air is entrained 14 and after mixing beidar streams as desiccant 14, 21 at a still high speed the catch tube 7 leaves-. The drying agent 14, 21 now applies to the. Entire surface of the article 1 and performs the dispensed-Articlefsuchte at high heat transfer coefficients with dsm, desiccant 14, 21 from. For the article drying air 14 is sucked through repeatedly arranged 'openings 13 and supplied via a fan and applied as a drying means 14, 21 the dryer 4 by passing items 1 through openings 15 promotes aer fan 17, the drying means 14, 21 via conduit 16, 18 to the free

or it is mixed as circulating air of the room air 14 partially or completely. Regulator valves 11, 12 and IS can be used to regulate the quantity.

Claims (1)

  claim. 1. A method for drying ceramic articles in the field asr Ledsrhart- and white drying characterized in that with ambient air (14) at a'.Temperatur of about '20 - 30 G and a relative humidity to ca' 70 %. and high Trocknüngsmittelgeschwindigkait in one , Drier (4) with a blowing device (5) dried Method according to item 1, characterized in that ambient air (14) acts as a drying agent (14, 21) on the ceramic articles (1) vertically or obliquely and from both sides'.