Vacuum Scraper Dryer

1. Product Overview An externally heated conductive batch dryer, specially developed for high-concentration mother liquor discharged from MEE (Multi-Effect Evaporation) and MVR (Mechanical Vapor Recompression) systems. It is mainly used for volume reduction of high-concentration saline wastewater mother liquor, realizing drying and volume reduction via vacuum low-temperature heating and scraper stirring. It greatly reduces enterprise disposal costs, with corrosion resistance and stable operation, supporting fully automatic batch operation, and is suitable for high-concentration mother liquor treatment in chemical, environmental protection and other industries. 2. Working Principle • Heating & Vacuum Environment: The drying cylinder is heated by steam or thermal oil through its outer jacket, with a stable vacuum of -0.08~-0.09 MPa (-80~-90 KPa) maintained inside. • Feeding & Drying Process: Evaporated mother liquor is pumped into the storage tank, then quantitatively fed into the drying cylinder at one time via a flowmeter. The stirring shaft rotates forward and reverse regularly, driving scrapers to agitate the material, ensuring full contact with the cylinder inner wall. Heat is transferred through the cylinder wall, making the material boil at 40~50 ℃, and moisture evaporates under vacuum. • Steam Treatment & Recycling: Secondary steam generated by evaporation is purified by a dust collector and demister, then condensed into water in the condenser and stored in the condensate tank, which can be reused as reclaimed water or discharged after secondary treatment. • Batch Cycle: After the mother liquor is dried into solid, the system is vented, and the dry material (granular or powdery) is pushed out by scrapers, collected and packed via a chute. The whole process is fully automatic controlled by PLC, with automatic cycle switching after each batch. 3. Core Features - High Vacuum & Low Energy Consumption: Operating vacuum: -80~-90 KPa; evaporation temperature: 40~50 ℃. No scaling, large heat transfer temperature difference, low moisture content of discharged material, and lower energy consumption. - Integrated & Intelligent Control: Integrates feeding, evaporation, drying, defoaming, condensation, vacuumizing and discharging; easy to install. PLC full-automatic control, with logical algorithm to judge drying end point, automatically adapting to feed concentration changes, avoiding over-drying or under-drying, and requiring minimal manual intervention. - Corrosion Resistance & Durability: Material contact parts: 2205 stainless steel (optional: 2205/316L/Titanium); secondary steam and condensate contact parts: 316L stainless steel. Mechanical seals at both ends of the stirring shaft ensure reliable sealing and long service life. - Stable Vacuum System: Equipped with automatic defoamer dosing device and demister to intercept entrained materials. The demister is automatically cleaned before each batch to avoid affecting the vacuum system. - Strong Targeted Performance: Specially designed for MEE/MVR system discharged mother liquor, solving problems such as evaporator scaling, pipe blockage and reduced evaporation capacity caused by COD, Ca²⁺, Mg²⁺ enrichment, ensuring stable operation of evaporators. - Environmental & Economical: Low evaporation temperature, low organic content in effluent, less tail gas; condensate water recyclable. Realizes mother liquor volume reduction, greatly reducing hazardous waste disposal costs. 4. Applicable Industries Mainly applied in chemical, environmental protection and other industries, dedicated to drying and volume reduction of high-concentration saline wastewater mother liquor discharged from MEE and MVR systems. It can treat mother liquor after ammonia distillation, supports non-standard customization and turnkey projects, adapts to batch intermittent processing needs, helping enterprises solve high-concentration mother liquor disposal problems and maintain stable evaporator operation.