Dense phase pneumatic conveying systems transfer product as a slug of material at slow speed under high pressure. Dense phase systems normally operate as a batch transfer system where a batch of materials is weighed and discharged into a pressure vessel. The vessel is then pressurised, and the discharge valve opened therefore forcing the material along the conveying pipeline. This type of conveying system causes less damage to delicate materials which are susceptible to degradation when transferred at higher speeds.

Material is transferred to the receiving vessel which is fitted with a reverse jet filtration system which separated the transferring air from the material via a series of filter cartridges. The cartridges are automatically cleaned between batches using reverse air jets.