How To Grind Titanium Dioxide?|Titanium Dioxide Grinding Mill For Sale

Titanium dioxide scientific name is titanium dioxide (TiO2), which is a white inorganic pigment with non-toxicity, excellent opacity, whiteness and brightness. Titanium dioxide accounts for more than 80% of all white pigments used, and is widely used in coatings, plastics, papermaking, printing inks, chemical fibers, rubber and cosmetics. In the production process of titanium dioxide, raw titanium ore, acid slag, finished titanium dioxide, etc. all need to go through the grinding process, so how to grind titanium dioxide? As a titanium dioxide grinding mill manufacturer, HCM will introduce you in detail next.

At present, there are two main ways to produce rutile titanium dioxide: sulfuric acid method and chlorination method. Compared with the two, the chlorination method tends to be used in most cases, because the pollution caused by the sulfuric acid method is more serious and the quality of the finished product is not high. However, although these two methods have different details in the specific implementation, the general production process is the same, which is composed of two parts: the production of titanium dioxide base material and the post-processing of it. The current domestic general titanium dioxide post-processing process: grinding-classification-coating-washing-drying-pulverizing-product.

1. Grinding

Grinding, also known as grinding and dispersing, is a process of mechanically grinding the TiO2 slurry dispersed by adding a dispersant, in order to separate the agglomerated TiO2 particles into individual particles. Commonly used mechanical grinding equipment is vertical mill, air-swept mill, Raymond mill, etc. The particles of titanium dioxide after grinding are spherical, without edges and corners, and the particle size below 2 μm is relatively concentrated.

2. Classification

The classification is to separate the large particles in the ground slurry, and further control the particle size of the titanium dioxide, so that the titanium dioxide particles reach the state of primary particles and meet the requirements of the coating. Domestic manufacturers generally use the method of gravity water separation to classify titanium dioxide particles, but this method has low efficiency, small production capacity, and it is difficult to control the particle size distribution of the product.

3. Envelope

The coating is the surface treatment, which is the core step in the whole post-treatment process and also the difficulty. There are many types of encapsulation methods currently, as shown in the figure. In China, a chemical reaction is generally used to form a film on the surface of the classified particles in a coating tank, and then various types of titanium dioxide products are obtained by adding different coating agents and changing the relevant conditions during the reaction. However, due to the late start of the domestic coating industry and the relatively insufficient technical production conditions, the overall level of the coating needs to be improved.

4. Washing

After surface treatment, the surface of the TiO2 slurry will adhere to a little water-soluble salt during the reaction process, especially the chloride group of chloride salts, which will seriously affect the application performance of the product (such as weather resistance, whiteness, etc.), Therefore, the salts must be removed by washing with water. The widely used washing equipment in China is the leaf filter. The leaf filter washing scheme has simple technological process, low investment, low operation requirements, and easy maintenance of the equipment. However, the washing water consumption is high, the solid content of the filter cake is low (35% to 40%), and a large amount of fuel needs to be consumed, resulting in high production costs.

5. Dry

After the titanium dioxide is washed and filtered, it contains a lot of water and needs to be dried. Common production processes mainly include spin flash drying, belt drying and spray drying. The heat utilization rate of spray drying is relatively high, but it is only suitable for materials with low solid content, while the heat utilization rate of belt drying is low, and the diameter of the discharge agglomerate is relatively large, which will increase the trouble for the subsequent processing process. The dryer used in spin flash drying is a continuous drying equipment, which has a high utilization rate of heat. However, domestic titanium dioxide production plants mainly use coal gas to provide fuel for the dryer, which has higher requirements for coal gas. , the sulfur and ash content in the gas are required to be relatively low.

6. Crush

Most of the titanium dioxide collected after drying are particle aggregates, which need to be pulverized to make the particle size meet the standard requirements, so as to obtain the highest possible opacity and covering performance. The titanium dioxide grinding mill produced by HCMilling(Guilin Hongcheng) can realize ultra-fine grinding of titanium dioxide with uniform particle size. The TiO solid powder with particle size less than 3mm and moisture content less than 0.5% can be ground into fine particle size powder with 325 mesh (0.045mm) sieve residue less than 0.1% and uniform particle size distribution.

Please contact mkt@hcmilling.com or call at +86-773-3568321, HCM will tailor for you the most suitable grinding mill program based on your needs, more details please check www.hcmilling.com.