Material metering units in the production of SSS

Modern plants for the production of dry mixes use a bunker system of unloading and dosing, which made it possible to move away from traditional designs with screws in favor of gravity installations.

Dried sand and other raw materials are fed to the top of the drying tower, from which the materials are moved by gravity. The design is based on a hopper unloading and dosing system based on fluidization technology. In most cases, this design does not require the use of screw conveyors, provides high accuracy and productivity, and is characterized by low maintenance volumes. The installation is very compact. Optimal unloading of the hopper is achieved by using fine raw materials: fine sand, limestone powder, cement, burnt lime and various dry powdered chemicals. Fluidization is an economical discharge method that requires a minimum amount of dry compressed air. Fluidization efficiency with minimal air consumption is achieved by installing special fluidization elements in the conical part of the hopper. In addition to these elements, a double gate is often used, which ensures accurate dosing of additives. It has a smaller built-in shutter inside for precise feed.

Recently, new gravity feed metering valves have appeared on the market, designed for less bulk materials, and are perfectly suitable for dosing gypsum flour or color pigments. The movement of the material is supported by a combination of fluidization and vibration, so that the metering valve is highly accurate and fast. It can dispense both very small and very large volumes of material.