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How to Find the Reasons for Uneven Mixing of Dry Powder

The reasons for uneven powder mixing should be

1、 Due to the unique characteristics of the powder involved in mixing, the mixing is uneven

Find out if the powder itself is difficult to mix from the following questions.

1. Reasons for significant differences in light and heavy powders

The difficulty in evenly mixing light and heavy powders is a classic mixing problem in the mixing process, which is caused by the sinking motion trend of heavy powders and the upward floating motion trend of light powders.

2. Reasons why ultrafine powder is difficult to mix

Ultrafine powder particles are extremely small, with weak gravitational binding. Like ultra-light powder, they are prone to floating during mixing motion, making it difficult to evenly mix into the main powder.

3. Reasons for poor liquidity and easy mixing

Excessive fluidity is also one of the reasons why it is difficult to mix evenly, as the surface of particles is too smooth during mixing, which can easily lead to light, heavy, and large and small segregation phenomena. Even after even mixing, there will be secondary unevenness.

4. Reasons for poor liquidity and easy mixing

Poor fluidity is also one of the reasons why mixing is not easy, as the surface roughness between particles during mixing affects their mobility, thereby slowing down the process of mixing and uniformity.

5. Reasons for uneven mixing of trace elements

Because the content of trace elements is too low (such as one thousandth), and the role of trace elements is very important, there is a relatively high requirement for the uniformity of trace element mixing. Therefore, it is necessary to ensure that the trace elements are mixed thoroughly and evenly, with a dispersed distribution, in order to meet the quality requirements of the end product. So the difficulty of mixing tasks with trace elements will greatly increase.

2、 Check if the selected mixing equipment meets the mixing requirements of the powder to be mixed

1. The problems caused by selecting a two-dimensional mixer

From the working principle of a two-dimensional mixer, it is analyzed that its motion mode is simple and the motion intensity is very low, so its mixing ability and efficiency are poor, and can only meet very simple mixing tasks. If encountering mixed tasks with a certain mixed difficulty, it may lead to mixed failure.

2. Problems in selecting three-dimensional mixers, V-shaped mixers, and double cone mixers

The mixing principle of these three types of mixers is mainly based on the gravity diffusion principle. In terms of mixing, powders with good mixing conditions (such as particle size, specific gravity, and moderate fluidity) can basically achieve the goal of uniform mixing.

If a powder with poor fluidity is encountered, it is difficult to mix evenly, leading to mixing failure.

If encountering the classic problem of mixing light and heavy powders, it is difficult to achieve uniform mixing due to the inability to overcome the floating problem of light powders.

3. Problems in Choosing Spiral Belt Mixers and Single Cone Mixers

The mixing principle of these two types of mixers is mainly the forced shear mixing principle. From the working principle of the mixer, there are dead corners of the material, so it is difficult to achieve uniform mixing when mixing powder containing trace elements. This is because once trace elements with very low content gather in dead corners, it will inevitably lead to mixing failure.

4. Choose dual motion ® Mixers can solve many of the difficulties in mixing work mentioned above

From dual motion ® The working principle of the mixer is analyzed, and its mixing principle is the mixing principle of gravity diffusion type mixing and forced shear type mixing. Therefore, choosing such a mixer can solve problems such as:

① The difficulty of mixing light and heavy powders;

② The difficulty of mixing ultrafine powder;

③ The problem of difficult mixing of trace elements;

④ Difficulty in mixing liquidity;

⑤ Mixed tasks with high difficulty and long mixing time.

3、 Finding the Causes of Uneven Mixing from the Perspective of Mixing Technology

1. The mixing of trace elements can be carried out using the mixing process of equal increment method

Due to the low content of trace elements, they are difficult to mix evenly. Therefore, the equal quantity increasing method of manual feeding can be used for mixing. Although this method can achieve the goal of uniform mixing, its drawbacks are also obvious, such as high labor intensity, complex operation, and error prone.

2. Powder materials with poor wet flowability, hardening, false particles, and clumping characteristics can be solved using a pre-treatment mixing process

The process method is to pre-treat the above-mentioned powder characteristics that do not meet the mixing conditions before the mixing process to achieve the pre mixing conditions.

For example, wet powder needs to be dried; Targeted process measures such as crushing are required for powders with excessively large or heavy particles.