Arrangement method of drying equipment fan

How should fans be arranged in drying equipment?

Centrifugal fans are commonly used in drying systems. Fans can be placed in drying systems using either a single induced draft fan or a dual blower-induced draft (EDD) configuration. Each approach has its own advantages.

A single ED fan is placed after the dust recovery unit, allowing the drying equipment to operate under negative pressure. The advantage of this drying system is that dust and harmful gases are prevented from escaping into the atmosphere. However, due to the high negative pressure within the drying equipment, frequent fan startup and shutdown can cause partial instability within the tower and allow outside air to leak into the dryer. Therefore, the single ED configuration is only suitable for small drying systems.

For large drying equipment, two fans are typically used: one blower and the other induced draft. This system offers greater flexibility and can adjust the pipeline pressure distribution to improve the operating conditions of the dryer, allowing it to operate at a slightly negative pressure close to atmospheric pressure. This not only takes into account the advantages of negative pressure operation, but also avoids the defect of air leaking into the system due to large negative pressure operation, resulting in reduced drying efficiency. At the same time, micro-negative pressure operation can ensure that the dust recovery equipment has the highest recovery rate.