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1. Selection of glass-lined agitators (1) Function of anchor-type (frame-type) agitators: Glass-lined anchor-type and frame-type agitators belong to the same category of agitators; the frame-type can be considered as a reinforced version of the anchor-type. This type of mixer is suitable for mixing materials with high viscosity, enabling thorough mixing of the material inside the container with few dead zones. The main function of the stirrer on the fluid is shear. Due to the large diameter of the stirrer arms and frames, which are located close to the inner wall of the container on the outside, their rotation has an effect similar to that of the container walls; this helps to thin the laminar boundary layer of liquid on the inner wall of the container, thereby improving the heat transfer efficiency through the jacket. This type of mixer is generally designed for low-speed mixing, with a rotation speed of ≤80 rpm; the liquid inside remains in a laminar state, making it a mild-type mixer. It is used in the coarse crystallization process, which facilitates grain growth and improves the yield of crystals during filtration in the subsequent step. It is also suitable for heat transfer processes, and to a certain extent it can increase the heat transfer coefficient (α2) between the material and the container walls; for liquid-liquid dispersion processes, this type of agitator is a more appropriate choice. (2) Function of the impeller-type (triple-blade swept-back type) mixer: The standard term for such mixers is impeller-type mixers (internationally known as triple-blade swept-back type). Its features include a simple structure, strong output performance, low power consumption, wide applicability, and the ability to ensure overall circulation of the fluid within the container (also known as volumetric circulation). It is currently a suitable type of mixer for materials with medium to low viscosity. This stirrer causes the fluid to move in a circumferential direction due to the action of the blades, and through the shear force exerted by these blades, it facilitates the breakdown and mixing of bubbles and droplets, increases the contact area, and accelerates the processes of heat and mass transfer. During rotation, the tip of the blade exerts a centrifugal force on the liquid, pushing it toward the container walls and creating upward and downward circulating fluid flows, thereby increasing the heat transfer coefficient α2 between the liquid and the jacket walls. The impeller mixer, when operating at a speed of 130 r/min, achieves a high circulation rate with low power consumption; it has a wide range of applicability and is primarily used for mixing non-Newtonian fluids (i.e., fluids whose viscosity changes during processing). An impeller mixer equipped with appropriate baffles is suitable for processes such as mixing, heat transfer, polymerization, emulsification, gas absorption, and suspension. It can achieve effective stirring with relatively low power consumption. During a reaction, the viscosity of the material tends to increase rapidly, while the increase in stirring power is minimal; therefore, this mixer is suitable for applications involving polymerization where viscosity rises. This stirring induces a particularly significant upward and downward circulation of the liquid within the container, ensuring uniform mixing. It also results in a high output per unit of power, which enables a high rate of volume circulation and strong flow intensity of the liquid; it is thus suitable for applications that require intense turbulent mixing. In summary, glass-lined impeller mixers are effective for operations such as homogeneous mixing, solid-liquid suspension, gas-liquid mixing, and heterogeneous dispersion. Their advantages include the ability to create a large volume of circulation, as well as strong mixing elements that provide significant shear force. (3) Function of the paddle stirrer: The paddle stirrer used in sugar glass standards features two speed settings with straight or folded blades; there are 4 blades in total, and it operates on a radial flow principle. Straight blades create a radial flow within the liquid in the container, while folded blades result in a flow that is primarily radial but also includes axial components. The rotation speed of the mixer is generally 80 r/min and 125 r/min, which constitutes slow mixing; the paddle mixer primarily generates significant shear forces on the liquid inside the container. With appropriate baffles, a certain degree of upward and downward discharge of the liquid can be achieved. However, the convection of this stirred liquid is relatively poor, making it suitable mainly for the dispersion crystallization of low-viscosity materials. (4) Function of the axial flow mixer: This type of glass-lined mixer is not included in the standards for glass products, yet its use has increased significantly in recent years. Due to the development of the chemical and pharmaceutical industries, users place great emphasis on the mixing efficiency and energy savings of mixers. This type of mixer is characterized by a high circulation rate of the liquid volume within the container, as well as low electrical energy consumption per unit volume of material; it represents a new type of mixer among glass-lined products. This mixer is primarily used in processes such as the suspension of solid particles, the dissolution of solids, the dispersion of gases in liquids and the absorption of gases by liquids, the mixing of immiscible liquids, liquid emulsification, suspension polymerization, and liquid mixing. It requires relatively low power consumption, especially when used for solid-liquid suspension operations. The liquid flow generated by the axial flow mixer is of a large-volume circulation type, featuring uniform and gentle shear action. The impeller has a strong pumping capacity, capable of generating a uniform axial fluid flow; this allows for the rapid elimination of unevenities in the concentration and temperature of two or more substances within the container, thus achieving uniformity quickly. 2. For glass-lined heat exchange vessels, ① vapor-liquid heat transfer is used: when the material is subjected to steam condensation, a disc-type condenser is selected. ②Heat transfer between liquids: When the material is a liquid and the cooling medium is also a liquid, a sleeve heat exchanger is used. Tubular heat exchangers: Suitable for processes where rapid heat transfer is required and a large heat transfer area is necessary.