Pneumatic conveying systems are used to convey powders, granules, and other dry bulk materials through closed pipelines. This conveying is powered by pressure differentials and the flow of a gas, such as air or nitrogen. Positive displacement blowers generate pressurized or vacuum air to provide the pressure differential along the pipeline. Depending on the type of application, pneumatic conveying systems can be designed in four different configurations: â?? Pressure conveying; for low and high volumes and long distances â?? Vacuum conveying; for unloading, short distances, collecting bulk materials from multiple points. â?? Combination vacuum-pressure pneumatic conveying systems. â?? Closed-loop pneumatic conveying systems; for materials that are sensitive to oxygen or moisture, nitrogen is often used in these applications. The correct selection of Roots blowers plays a vital role in the overall performance of the pneumatic conveying system. The physical and chemical properties of the bulk material, the conveying capacity, the conveying distance, and the environmental conditions are key factors in determining the appropriate type and size of Roots blowers.