Process monitoring with in-line sensors involves the use of sensors that are placed directly within the moving stream of a process to measure various parameters such as temperature, pressure, flow rate, and chemical composition. This type of monitoring allows processes to be monitored in real-time, providing operators with immediate feedback on process performance. In-line sensors can be used in a variety of industries, including pharmaceuticals, food processing, and oil and gas, and can help improve process efficiency, reduce downtime, and improve product quality.
The utilization of in-line and online sensors for monitoring industrial mixing processes has become pivotal in enhancing adhesive production efficiency. This article provides a comprehensive review of various sensor techniques tailored for process control, particularly within the framework of Industry 4.0. Encompassing diverse industries such as pharmaceuticals, food, polymers, rubber, cement, and concrete, this exploration delves into liquid-liquid, gas-liquid, solid-liquid, solid-gas-liquid, and solids mixing applications. Beyond conventional methods, spectroscopic and tomographic techniques are also examined, shedding light on the myriad possibilities for optimizing adhesive manufacturing processes.
Some instruments commonly used to measure parameters in various industrial mixing processes are:
Flowmeters:
Electromagnetic flowmeters are used for measuring liquid flow rates.
Pressure Transmitters:
- Differential pressure transmitters for monitoring pressure differentials in pipelines and vessels.
- Absolute pressure transmitters for measuring the total pressure within closed systems.
Temperature Sensors:
Thermocouples for measuring temperature gradients in mixing vessels and pipelines.
Resistance temperature detectors (RTDs) for precise temperature measurement in various media.
pH Meters:
- pH meters for monitoring acidity or alkalinity levels in liquid mixtures are crucial for pH-sensitive processes.
Viscometers:
- Rotational viscometers for determining the viscosity of liquid mixtures, are essential for understanding flow behavior and consistency.
Conductivity Sensors:
- Conductivity sensors for measuring the electrical conductivity of solutions, indicating the concentration of dissolved ions.
Spectroscopic Analyzers:
- Near-infrared (NIR) spectrometers for non-destructive analysis of chemical composition in liquid mixtures.
- UV-Vis spectrophotometers for measuring absorbance and transmission properties of liquids, aiding in qualitative and quantitative analysis.
Imaging Systems:
- High-speed cameras for visualizing flow patterns and mixing dynamics in real time.
- X-ray imaging systems for non-invasive visualization of solid-liquid and solid-gas-liquid mixing processes.
Density Meters:
- Density meters for determining the density of liquid mixtures, crucial for quality control and process optimization.
Particle Size Analyzers:
- Laser diffraction particle size analyzers for characterizing particle size distribution in suspensions and emulsions.
- Dynamic light scattering (DLS) analyzers for measuring particle size and distribution in colloidal systems.