Oxalic acid delivery device

Abstract

The invention discloses an oxalic acid conveying device. The oxalic acid conveying device comprises a box, a box cover and a plurality of separation plates. The box is formed by an upper side plate, a lower side plate, a left side plate, a right side plate and a rear side plate in a surrounded mode. The box cover covers a front side box opening of the box in a seal mode. The separation plates are arranged up and down and welded in the box. The box is divided into a plurality of areas by the separation plates. A heating plate is installed in each area. A gas inlet connector used for leading in nitrogen gas is arranged in the position, close to the bottom end, of the left side plate or the right side plate of the box. The separation plates are provided with ports for ventilation. A gas outlet connector is arranged on the upper side plate and is provided with a gas channel used for communicating with a furnace liner reaction cavity of a debinding furnace. According to the designed oxalic acid conveying device, supply of a gas oxalic acid catalyst is achieved, thus the debinding furnace decomposes polyformaldehyde through gas oxalic acid as the catalyst, the problem that oxalic acid can enter the debinding furnace after sublimation in the catalytic debinding process is solved, so that conveying supply can also be completed without the usage of compressed air.

Description

technical field [0001] The invention relates to an auxiliary device for a degreasing furnace, and more particularly relates to an oxalic acid conveying device applied to a catalytic degreasing furnace in metal injection molding and ceramic injection molding. Background technique [0002] The process principle of catalytic degreasing is to use the characteristics of solid polyoxymethylene (POM) to quickly crack into gaseous formaldehyde molecules under an acidic atmosphere at a certain temperature (about 100 ° C), in which the acid exists as a catalyst. Its cracking formula is as follows: [0003] (CH 2 O) n (acidic solution)—→nCH 2 o [0004] At present, the catalyst commonly used in catalytic degreasing process is nitric acid (HNO 3 ), a diaphragm pump or plunger pump is generally used to complete the delivery of nitric acid to the degreasing furnace. The structure principle of plunger pump is as follows: figure 1 As shown, when the eccentric wheel 71 controls the pi...

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Problems solved by technology

[0008] Therefore, it is not conducive to the application of catalytic degreasing technology to these metal powders that are easily oxidized by nitric acid

[0009] 2. Nitric acid produces a large amount of nitrogen oxides, which cannot be effectively decomposed and pollutes the atmosphere. There is HNO in the exhaust gas 3 and NO x , is one of the causes of acid rain, which is harmful to the environment and can cause pollution to water bodies, soil and the atmosphere

[0011] 1. The existing gaseous conveying device cannot maintain high-temperature operation, because oxalic acid begins to sublimate at 100°C, it is easy to condense, and it is easy to cause channel blockage and affect production. It is not suitable to use traditional gaseous conveying devices; and traditional gaseous conveying devices only realize A large amount of delivery, unable to achieve quantitative delivery

[0012] 2. The existing gaseous conveying devices use air compressors to complete the conveying, and a large amount of air will flow in immediately, because the catalytic degreasing process of metal injection molding and ceramic injection molding cannot have air inflow, otherwise serious safety accidents will occur. Therefore, the air compression method cannot be used for gaseous transportation; moreover, it must be completely sealed without air leakage, which cannot be achieved by existing transportation devices.

[0013] 3. In addition, the existing gaseous conveying device takes up a lot of space, the procedure is complicated, and the price is expensive, which will bring a certain economic burden to some small and medium-sized enterprises with small scale and low output, and hinder the development of enterprises

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