Silo cleaning

Silo cleaning is a process to maximize the efficiency of storage silos that hold bulk powders or granules. In silos, material is fed through the top and removed from the bottom. Typical silo applications include animal feed, industrial powders, cement, and pharmaceuticals.

Free movement of stored materials, on a first-in, first-out basis, is essential in maximizing silo efficiency. The goal of silo efficiency is to ensure that oldest material is used first and does not contaminate newer, fresher material. Two main problems, rat holing and bridging, complicate silo efficiency. When rat holing occurs, powders adhere to the sides of silos. Bridging occurs when material blocks at the silo base.

Manual cleaning, by lowering a worker on a rope to free material, is the simplest way to clean silos. However, manual cleaning is dangerous due to the release of material and the possible presence of gases. In cases of bridging, an additional danger exists as the exit hole needs to be rodded from underneath, exposing the worker to falling powder.

Alternative cleaning methods include:

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