Slurry 3: Vacuum and Pressurised Air Systems for Slurry Transport
     1. INTRODUCTION
         1.1 Scope of Review
         1.2 Parts of a Pneumatic Conveying System
         1.3 Classification of Air Transport Systems
             1.3.1 Non-Newtonian Pseudohomogeneous Slurries or Pastes
             1.3.2 Settling Slurries
     2. SYSTEMS FOR SLURRIES
         2.1 Compressed Gas Systems
             2.1.1 Gas Injection combined with a Pump
             2.1.2 Gas Injection combined with Compressed Gas Hopper Feed
             2.1.3 Air-Lift Pump
             2.1.4 Pneuma Pump System
         2.2 Vacuum Systems
             2.2.1 Vacuum System without Air Bleed
             2.2.2 Vacuum System with Air Bleed
     3. SELECTION AND DESIGN OF SLURRY SYSTEMS
         3.1 Selection of Slurry Systems
         3.2 Design of Fine Particle, "Non-settling" Slurry Systems
             3.2.1 Measurement of slurry/paste flow properties
                 3.2.1.1 Selection of viscometer and test conditions
                 3.2.1.2 Use of appropriate flow model
                 3.2.1.3 Calculation of appropriate Reynolds number
             3.2.2 Identification of flow pattern
                 3.2.2.1 Horizontal pipe flow
                 3.2.2.2 Vertical pipe flow
             3.2.3 Air Injection into Discharge Pipe of a Pump
                 3.2.3.1 Prediction of extent of frictional pressure loss reduction in laminar flow
                 3.2.3.2 Prediction of pressure loss in turbulent flow
                 3.2.3.3 Prediction of conditions for maximum power savings
             3.2.4 Design of Air-lift Pump for "Non-Settling" Slurries
         3.3 Design of Coarse Particle, Settling Slurry Systems
             3.3.1 Design to reduce pressure drop and limit deposit velocity
             3.3.2 Design of air-lift pump for coarse solids lifting
     4. CASE STUDIES
         4.1 Transport of Carbonatation Mud in the Sugar Industry
         4.2 Concrete pump
         4.3 Asbestos slurry transfer
         4.4 Recovery of Food Pastes from Pipework
         4.5 Raising of Consolidated Sediment using a Vacuum System with Air Bleed
         4.6 Dredging Mud sediment using Compressed Air
     5. RESEARCH REQUIREMENTS
     6. NOMENCLATURE
     7. REFERENCES
         7.1 Non-Newtonian Slurries and Pastes (and polymer solutions)
         7.2 Settling Slurries
         7.3 RELATED REFERENCES FOR AIR/NEWTONIAN FLOWS
     8. SUPPLIERS OF PNEUMATIC CONVEYING SYSTEMS
     Legal Notices

• Part 1 Vacuum and Pressurised Air Systems for Slurry Transport

Volume SH 3: Part 1 Vacuum and Pressurised Air Systems for Slurry Transport

This part considers the transport of coarse or fine particle slurries using either compressed air or vacuum pumping systems.

Both high viscosity, fine particle slurries or pastes and coarse particle settling slurries can be transported more efficiently using either a compressed air or vacuum system. Injecting air into a viscous shear-thinning slurry in laminar pipeflow results in a decrease in the pressure gradient along the pipe. This can reduce pumping power consumption and facilitate the pipe transport of some particularly viscous slurries that could not otherwise readily be pumped. In addition, it may be possible to reduce the limit deposit velocity for the flow of settling solids in a horizontal pipe through air injection, although this has yet to be properly investigated. For both types of slurries, an air-lift pump is a very inexpensive option which is worth investigation for applications such as coal raising in mine shafts, dredging and removing compacted sediment from lagoons.

The review describes practical systems and provides equations for determining design parameters such as pressure drop.