Powder processing is fundamental to manufacturing across a vast range of industries, from food and pharmaceuticals to chemicals, ceramics, and additive manufacturing. The properties of powders, including flowability, compressibility, dissolution rate, and reactivity, are profoundly influenced by particle size distribution. Laser diffraction technology has become the gold standard for particle size measurement in industrial powder processing, offering the combination of speed, accuracy, and reproducibility that modern manufacturing demands.
Principles of Laser Diffraction
Laser diffraction measures particle size by analysing the angular distribution of light scattered when a laser beam passes through a dispersed particulate sample. Larger particles scatter light at smaller angles relative to the laser beam, while smaller particles scatter at wider angles. By measuring the intensity of scattered light across a range of angles using a multi-element detector, laser diffraction instruments calculate the particle size distribution that best explains the observed scattering pattern.
The technique offers several inherent advantages for powder processing applications. Measurements are fast, typically completed in seconds, enabling real-time monitoring and high-throughput quality control. The wide measurement range, from tens of nanometres to several millimetres, covers the full spectrum of industrial powder sizes in a single instrument. Sample preparation is straightforward, with both wet and dry dispersion options available to suit different material types and processing requirements.
Applications in Key Industries
- Cement and building materials β Controlling clinker fineness to optimise setting time, strength development, and energy efficiency in cement grinding
- Food and beverage β Monitoring particle size in flour milling, chocolate refining, spray drying, and emulsion processing for consistent product quality and texture
- Chemical manufacturing β Ensuring consistent particle size in pigments, fillers, catalysts, and agrochemical formulations
- Additive manufacturing β Characterising metal and polymer powders to ensure optimal flowability, packing density, and layer uniformity in 3D printing processes
- Ceramics and glass β Controlling particle size distribution to achieve desired sintering behaviour, microstructure, and mechanical properties
Wet and Dry Dispersion Strategies
Effective sample dispersion is critical for accurate particle size measurement. Our instruments offer both wet and dry dispersion options, each optimised for specific sample types and applications. Wet dispersion, where particles are suspended in a liquid medium with appropriate surfactants and ultrasonic treatment, is the default choice for most applications. Dry dispersion, where particles are dispersed in a compressed air stream, is preferred for materials that are sensitive to liquid contact, dissolution, or swelling, and for applications where the dry powder properties are of primary interest.
Process Analytical Technology Integration
The integration of laser diffraction analysers into manufacturing processes represents a significant advancement in powder processing efficiency. By installing instruments at critical points in milling, grinding, blending, and classification circuits, manufacturers can implement closed-loop control systems that automatically adjust process parameters to maintain target particle size specifications. This approach eliminates the delay between sampling and laboratory analysis, reduces off-specification production, and enables continuous process optimisation.
Standardisation and Method Development
International standards including ISO 13320 and USP Chapter 429 provide frameworks for laser diffraction measurement methodology. Our application scientists support customers worldwide in developing standardised measurement methods that comply with regulatory and industry standards, ensuring that particle size data is reliable, reproducible, and defensible across manufacturing sites and supply chains. By combining world-leading instrument technology with comprehensive application support, Malvern Panalytical helps powder processors achieve the measurement confidence they need to deliver consistent, high-quality products.