Colloidal mill grinding device in blending and preparation of heavy oil and fuel oil It is preferred to develop and utilize heavy oil fuel oil to completely or partially replace heavy oil fuel oil. Water-in-oil coal synthesis fuel oil for coal-based boilers is a technology of replacing oil with coal. It uses pulverized coal, coking by-products-coal tar, heavy oil, water, surfactant, emulsifier and catalyst as main raw materials to prepare liquid-solid slurry fuel for boilers through technologies such as blending, emulsification and grinding to accelerate homogenization. Because coal tar and pulverized coal are coal-based substances, this technology is a colloid mill. The main research contents are as follows: using coal tar and heavy oil as raw materials, blending oil is prepared by colloid mill shearing; Adding proper emulsifier and water into blended oil to prepare environment-friendly fuel emulsified oil for boiler;Study on viscosity reducer for reducing the viscosity of blended oil: Oil-coal slurry was prepared from blended oil and pulverized coal with a certain particle size. The main research results and conclusions are as follows: 1) The viscosity of blended oil is significantly affected by the increase of temperature. When the blending ratio is 2:1, the viscosity decreases by 94.2% from 50℃ to 92℃. 2) With the increase of heavy oil ratio from 2:1 to 7:1, the viscosity of blending oil increases correspondingly, and with the increase of temperature, the viscosity of blending oil decreases, and the decreasing rate is divided into two stages, the first stage is a high-speed decreasing zone (50℃T70℃) with an average decreasing rate of 115 mpas/℃, and the second stage is a gentle decreasing zone (70℃T92℃) with an average decreasing rate of 20 mpas. 3) When the blending ratio of heavy oil and coal tar is 6:1, it is blended at 50℃ under the main effects of high-speed shearing, dispersion, mixing, emulsification, homogenization, crushing and grinding by Haoxing CN.HAOSTAR multifunctional colloid mill. Colloid mill grinding device Except for the motor and some parts, all parts in contact with materials are made of high-strength stainless steel 304, 316, 316L, 2205 and alloy steel. In particular, the key dynamic and static grinding discs are strengthened. Therefore, they have good corrosion resistance and wear resistance, making the processed materials pollution-free, hygienic and pure, and can also be customized according to the special requirements of users.