Tube sterilizer is an efficient and reliable continuous heat exchange equipment widely used for pasteurization or high-temperature short-time (HTST) sterilization of liquid foods such as juice, milk, and beverages. The core working principle is to use the product to be sterilized flowing inside the tube and the heat medium (or refrigerant) flowing outside the tube to indirectly exchange heat through the stainless steel tube wall, in order to achieve the process goals of rapid heating, precise insulation sterilization, and rapid cooling.
Core working principle and component analysis
Heat exchange structure:
The core component is a bundle of hundreds of thin-walled stainless steel tubes arranged in parallel and fixed on the tube plate. The product flows inside the tube, while the heat transfer medium (hot water/steam for heating and ice water for cooling) flows in the opposite direction outside the tube (shell side).
This "tube shell" reverse flow design, along with a large heat transfer area, achieves extremely high heat transfer efficiency.
Accurate control of the manufacturing process:
Heating section: The product is quickly and evenly heated to the preset sterilization temperature (e.g. 72-85 ° C for pasteurization, 85-127 ° C for HTST sterilization).
Insulation section: The heated product flows into an insulation tube (or holding section) and is maintained at this precise temperature for a precise time (usually several seconds to tens of seconds) to kill pathogens and the majority of spoilage bacteria, while minimizing damage to the product's color, flavor, and nutrition.
Cooling section: The sterilized product is quickly cooled to the required low temperature for filling (such as 4-25 ° C), and the cold released in the cooling section is often recycled to preheat the newly entered cold product, significantly saving energy.
Homogenized fluid treatment:
The product flows in a turbulent state inside the tube, ensuring uniform heat transfer, avoiding overheating or insufficient heating of some products, and reducing material coking or deposition on the tube wall.
System composition and advantages
A complete tubular sterilizer system typically includes:
Material balance cylinder and conveying pump
Hot water system (or steam injection system) and temperature controller
Ice water system
Automated control systems and safety devices (such as temperature recorders, automatic steering valves, etc.)