DR Vol 12 : Recommended Procedures
     Introduction to the Drying Recommended Procedures
     1. Experimental Methods
         1.1 Moisture measurement
             1.1.1 Measurement of solids moisture content (general)
             1.1.2 Determination of moisture content by weight-loss (oven test) technique
         1.2 Drying kinetics
             1.2.1 Measurement of drying kinetics (general)
             1.2.2 Determining a drying curve by sampling or periodic weighing techniques
             1.2.3 Determining a drying curve by indirect (humidity measurement) method
         1.3 Drying equilibria
             1.3.1 Measurement of the equilibrium moisture content of a material (general)
             1.3.2 Simple measurement of the equilibrium moisture content of a material at ambient conditions
             1.3.3 Measurement of hydration or solvation level or polymorph form of a material under drying conditions
         1.4 Measurement of the humidity of a gas stream
         1.5 Materials handling properties
             1.5.1 Measurement of stickiness and materials handling properties (general)
             1.5.2 Measurement of the cohesion peak for a powder by a simple backmixing test
             1.5.3 Use of Warren Spring / Ajax tester to determine cohesion and adhesion
                 1.5.3.1 Introduction
                 1.5.3.2 Equipment
                 1.5.3.3 Preparation procedure
                 1.5.3.4 Procedure for a cohesion test
                 1.5.3.5 Performing a cohesion measurement
                 1.5.3.6 Alternative measurement method
                 1.5.3.7 References
                 1.5.3.8 ANNEX: WSL Cohesion test results sheet
             1.5.4 Measurement of the sticky-point temperature and thermal effects
             1.5.5 Measurement of cohesion and lump formation in a laboratory rotary evaporator-dryer
                 1.5.5.1 Introduction
                 1.5.5.2 Equipment
                 1.5.5.3 Preparation procedure
                 1.5.5.4 Procedure for a test
             1.5.6 Measurement of flowability and dynamic coefficient of friction (angle of repose)
                 1.5.6.1 Method 1 –Cone angle
                 1.5.6.2 Method 2: Hollow cylinder
         1.6 Other solids properties
             1.6.1 Measurement of bulk density of solids
             1.6.2 Measurement of particle (true) density
             1.6.3 Measurement of particle size distribution by sieve analysis
             1.6.4 Measurement of particle shape factor
             1.6.5 Thermal stability and heat sensitivity
             1.6.6 Measurement of agglomeration and balling-up effects
             1.6.7 Evaluation of attrition and dustiness
             1.6.8 Measurement of fluidisation velocity
             1.6.9 Use of optical microscopes and scanning electron microscope
     2. Initial Selection and Design Procedures
         2.1 Selection and Process Development
             2.1.1 Development of an overall solids processing flowsheet
             2.1.2 Selection of a suitable dryer
         2.2 Basic drying calculations
             2.2.1 Interconversion between humidity parameters
                 2.2.1.1 Introduction
                 2.2.1.2 Humidity terminology
                 2.2.1.3 Invariant and variable parameters
                 2.2.1.4 Systems other than air-water
                 2.2.1.5 Main humidity parameters and their calculation
                 2.2.1.6 Some common humidity calculations
                 2.2.1.7 References
                 2.2.1.8 Example Calculations
             2.2.2 Performing a heat and mass balance on a dryer
         2.3 Scoping (approximate) dryer design
             2.3.1 Scoping design of continuous convective dryers
             2.3.2 Scoping design of continuous contact dryers
             2.3.3 Approximate sizing of batch dryers with known batch size
         2.4 Detailed thermal design of a dryer
             2.4.1 Thermal design of a fluidised bed dryer
             2.4.2 Design of a pneumatic conveying (flash) dryer
             2.4.3 Design of a cascading (direct) rotary dryer
             2.4.4 Design of a convective through-circulation layer dryer
             2.4.5 Design of a convective cross-circulation layer dryer
             2.4.6 Design of a contact (conduction heated) layer dryer
             2.4.7 Design of a dielectric (radiofrequency or microwave) dryer
             2.4.8 Design of a spray dryer
     3. Dryer Operations
         3.1 Developing a reliable heat and mass balance for a dryer
         3.2 Performing on-plant measurements of essential process data
         3.3 Troubleshooting a dryer problem
             3.3.1 Introduction
             3.3.2 Problem Definition
             3.3.3 Data Collection
             3.3.4 Identification of Problem Cause
             3.3.5 Assessment of Possible Solutions
             3.3.6 Monitoring of Results

This volume will bring together the various experimental techniques described in various Manual Volumes and Research Reports. It will also present them in a standardised format, that of the SPS Recommended Procedures, to enable members to use the methods themselves and obtain reproducible results. Detailed descriptions of specific techniques and experimental rigs, including operating instructions, will be provided where appropriate. Recommended Procedures will also be provided for other areas of general usefulness, such as conducting literature searches using the SPS database. Individual Recommended Procedures will be produced as the opportunity arises.