What’s on a Blending Skid?

A blending skid typically consists of several instruments and components that work together to facilitate the blending process. While the specific configuration may vary depending on the application and industry, here are some common instruments and components found on blending skids:

1. Storage Tanks or Silos: These containers store the materials to be blended, such as liquids, powders, or granules. They are typically designed to hold the required volume of each component, allowing for easy access and controlled dispensing.
2. Metering Devices: These instruments accurately measure the flow rates of different components during the blending process. They can include flow meters, mass flow controllers, or volumetric measuring devices. Metering devices play a critical role in achieving precise blend ratios.
3. Control Valves: These valves regulate the flow of materials through the system. They can be manually operated or automated, allowing for accurate control of the flow rates and blending ratios. Control valves can be actuated by pneumatic, hydraulic, or electric mechanisms.
4. Pumps: Pumps are used to move liquids or slurries from storage tanks to the blending skid and through the blending process. They create the necessary pressure and flow rates to ensure efficient blending.
5. Mixers: Mixers, such as agitators or static mixers, are used to thoroughly blend the components, ensuring uniform distribution and homogeneity of the mixture. These mixers can be positioned in-line or within blending tanks to facilitate the blending process.
6. Sensors and Transmitters: These instruments monitor various parameters during blending, such as temperature, pressure, level, and pH. They provide real-time feedback to control systems, allowing for continuous monitoring and adjustment of the blending process.
7. Control System: The blending skid is typically equipped with a control system that integrates the various instruments and components. It allows for automated control and regulation of flow rates, blend ratios, and other blending parameters to ensure consistency and accuracy.
8. Safety Devices: Safety devices, such as pressure relief valves, emergency stop buttons, or alarms, are incorporated into blending skids to ensure the safe operation of the system, protect against overpressure or hazardous conditions, and comply with safety regulations.

It’s important to note that the specific instruments and components on a blending skid can vary depending on the specific requirements of the application. Industrial standards, safety regulations, and the nature of the materials being processed also influence the selection of instruments and components.

On a blending skid, different types of flow meters can be used to accurately measure the flow rates of the components being blended. The choice of flow meter depends on factors such as the nature of the materials, flow rates, accuracy requirements, and budget considerations. Here are some commonly used flow meters on blending skids:

1. Differential Pressure (DP) Flow Meters: DP flow meters, such as orifice plates, Venturi tubes, or flow nozzles, utilize the pressure difference across a constriction in the flow path to determine the flow rate. These meters are widely used due to their simplicity and cost-effectiveness. However, they may require additional calculations and compensation to accurately measure non-ideal fluids or handle varying process conditions.
2. Magnetic Flow Meters: Magnetic flow meters, also known as electromagnetic flow meters, use Faraday’s Law of electromagnetic induction to measure the flow rate of conductive liquids. They are particularly suitable for applications with high flow rates and conductive fluids, such as water or chemicals. Magnetic flow meters offer good accuracy, low-pressure drop, and resistance to corrosion and clogging.
3. Coriolis Flow Meters: Coriolis flow meters rely on the Coriolis effect, which measures the mass flow rate by detecting the deflection of fluid flowing through vibrating tubes. These meters can measure mass flow directly and are known for their high accuracy, consistency across a range of fluid properties, and suitability for various types of liquids and slurries.
4. Ultrasonic Flow Meters: Ultrasonic flow meters utilize ultrasonic signals to measure the flow rate by calculating the time it takes for the sound waves to travel through the fluid. They come in two types: Doppler and transit-time. Doppler flow meters measure the change in frequency caused by particles or bubbles in the fluid, while transit-time flow meters measure the time difference between upstream and downstream signals. Ultrasonic flow meters are non-intrusive, meaning they do not contact the fluid, making them a good choice for clean and non-conductive fluids.
5. Volumetric Flow Meters: Volumetric flow meters, such as positive displacement meters or turbine meters, measure the flow rate by directly calculating the volume of fluid passing through the meter. They are suitable for applications where accurate volume measurement is crucial. Positive displacement meters are commonly used for viscous liquids, while turbine meters are often used for clean liquids with high flow rates.

The selection of a flow meter for a specific blending skid depends on factors like the characteristics of the materials being blended, the required accuracy, maintenance considerations, and budget constraints. It is important to consult with industry experts or flow meter manufacturers to determine the most suitable flow meter for a particular blending skid application.