Optimise industrial HVAC systems and cooling processes

Optimising industrial HVAC systems is a topic that will always resonate with plant engineers, because the energy consumption generated by such climate control and process equipment responsible for supplying airflow, heating, curing, or cooling, is directly proportional to the electricity cost.

Therefore, any opportunity to improve quality at a lower unit cost is of great interest to the energy industries and HVAC system suppliers, similarly when a significant and rapid return on investment (ROI) is foreseen for those patented processes with competitive advantages. 

While it's true that there are currently many opportunities to optimise industrial HVAC systems with flow measurement, through the selection of sensors or flow meters for heating, ventilation, air conditioning (HVAC), and process control systems, it's also important for plant engineers to understand the functionality of these new trends.

Among the flow measurement solutions that enable improved performance and optimisation of industrial HVAC systems are:

• Differential pressure (DP) flow meters: They measure volumetric flow rate and, depending on the secondary technology (orifice plates, averaging Pitot tubes, Venturis, sonic nozzles, and V-cones), are applicable to most liquids, gases, and vapours, and are also easy to use.
• Positive Displacement (PD) flow meters: They measure the volumetric flow rate of a liquid or gas by separating the flow stream into known volumes and counting them over time. 
• Turbine flow meters: They are based on a rotating rotor, which allows them to optimise industrial HVAC systems by measuring flow in clean liquids and gases, however, they introduce a pressure drop and their moving parts are subject to wear.
• Electromagnetic measurement technologiesThey determine the speed of a conductive liquid by passing it through a magnetic field and measuring the voltage developed. 
• Coriolis Devices: It is one of the 5 technologies used in hydrocarbon flow measurement for custody transfer and optimise industrial HVAC systems, they measure mass flow in liquids, slurries or gases by means of a vibrating flow tube and the reading compensates for any effects due to differences in temperature or density in the fluid.
• Ultrasonic systems They focus around transit time or Doppler frequency shift to measure average fluid velocity, these types of systems present no flow obstructions and the clamping type is non-intrusive.
• Vortex shedding devices They are particularly effective and one of the few applicable technologies for steam applications. These units have no moving parts and are tolerant of scaling, and they take advantage of the fact that the frequency with which vortices shed from a body placed in the flow stream is proportional to the fluid velocity.
• Thermal sensors Measuring the heat gain or loss of a fluid directly is often the most effective and economical solution for large pipelines or duct or stack applications.

What are the selection factors to consider for optimising industrial HVAC systems?

1. The first factor to consider before selecting a technology to improve efficiency and optimise industrial HVAC systems is to ensure the method matches the means of use, such as air, special process gases, or refrigeration processes.
2. Check that the accuracy, repeatability and flow range in the manufacturer's specifications match the plant's requirements, as accuracy and range can differ in water, air or gas.

It is recommended to observe the repeatability specification of a flow meter, which indicates how reliable the device is in maintaining its accuracy and managing plant safety during a production boom.

3. Consider the operating environment into which the new solution will be placed, such as the number of changeovers, the extremes of climatic temperature, and specific process humidity requirements, as some technologies are better suited for taking precise measurements in extremely low flows, dealing with high reduction or pressure-drop rates. 
4. Please can you clarify if the device can be directly inserted into the process pipe, or if it requires an inline configuration that would involve cutting and splicing the pipe in multiple places. This is of paramount importance as pressure drops cause costly inefficiencies and minimise the possibility of optimising industrial HVAC systems.
5. Consider the maintenance requirements for the flow sensor or meter, therefore, it is not only essential to look beyond the purchase price but to determine the initial cost, total installation cost, and the lifecycle cost. 

Some inexpensive flow meters require frequent maintenance or have a short lifespan, whereas more expensive ones are easier and less costly to install, maintain, and have a longer lifespan, providing a much better ROI and optimising industrial HVAC systems.

Accurately selecting sensors and flow meters is fundamental to increasing the efficiency of industrial HVAC systems and process equipment. For this reason, before starting, the available flow measurement technology options must be identified, along with their advantages and limitations, based on the plant's unique operations.

Considering the factors described above will allow for the determination of potential energy savings and justify the upgrade of industrial HVAC systems. If you wish to discover How digitisation can improve the safety of industrial processes y optimizar sistemas de climatización industrial, te invitamos a suscribirte al Technology for Industry Newsletter, a place where you can learn about new solutions available on the market to optimise your plant's operations.