The Raymond(R) flash drying system was designed in the early 1920’s as an integral addition to our size reduction and classification equipment product line. We maintain a database of drying and design specifications to draw from when engineering your system. As a result, we are able to provide proven designs for unique applications and ensure that each system will perform to your specifications.
Raymond(R) Cage Mill
The cage mill design consists of an agitator type rotor enclosed in a welded steel housing with carbon steel liners and a tangential outlet. A rotor and blade assembly with sets of variable length, carbon steel bars are arranged and welded concentrically on a steel spider.
The cage mill housing is provided with bolted, machined, gas and dust tight, flanged joints. The v-belt driven mill is supplied with heavy-duty self-aligning ball bearings that allow for trouble free, smooth operation under the high temperature conditions the mill experiences.
Raymond(R) Cage Mill Flash Drying System
The cage mill flash drying system design consists principally of a feed conveyor, cage mill, air heater, and dust collector and system fan along with the connective ductwork to incorporate these components into a complete system.
The feed material is discharged from the feed silo into the cage mill feeder then into the feed inlet of the cage mill flash dryer.
Once the material enters the cage mill, it is vigorously agitated while being combined with the hot gas stream from the air heater. The cage mill creates turbulence and retention time for more efficient drying. The cage mill flash drying system gets its high thermal efficiency from the use of a high temperature differential between the inlet and vent temperatures. Its short retention time in the hot zone results in lower product temperatures compared to other dryer methods. This reduces the heat losses to the product and lowers the risk of calcining during the drying phase. The circular motion of the rotor helps tangentially direct the feed into the drying column and on into the primary collector where the drying process is completed.
The feedstock is metered out of the silo into the cage mill flash drying system that produces a uniform surface moisture material. This initial process step delivers a more consistent feed (landplaster) to the flash calcining system. It greatly improves control of the calcining process by smoothing out large temperature swings that can occur with the widely variable feed moistures these types of materials can experience. The improved feed consistency prevents sudden swings in feed moisture from causing fluctuations in the stucco’s combined water that can cause problems on the boardline. A primary cyclone and/or baghouse acts as the collection vessel for the product while a system fan serves as the primary air mover.
The dried synthetic gypsum (landplaster) is then discharged into a transfer screw conveyor for transport and distribution into a feed silo located ahead of the calcining systems.
Advantages of the Raymond(R) Cage Mill System
- Disintegrates and agitates material.
- Improves drying by increasing turbulence and retention time.
- Accepts a wide range of material size and moisture conditions.
- Heavy-duty design for continuous 24-hour operation, minimum maintenance.
- Low product temperatures are advantageous for heat sensitive materials.
- Rotor mounts on retractable carriage and includes replaceable blades.
- Available with flash drying/calcining.