Thermal processes often involve both heating and cooling stages. As a treated product or liquid effluent cools, some of its thermal energy may still be available for reuse.
Where operating conditions allow, this heat can be recovered and transferred to incoming process fluids, reducing the additional energy needed to bring them to the required temperature.
Actini Group integrates heat recovery solutions into selected thermal processing equipment for industrial facilities, laboratories and pilot-scale applications.
The aim is to reduce heating and cooling demand while maintaining the process conditions required for effective treatment.
Heat recovery involves transferring thermal energy from a warmer fluid to a cooler one through a heat exchanger.
In processes with heating and cooling stages, the outgoing treated fluid can be used to preheat the incoming fluid, recovering heat that would otherwise be rejected during cooling.
Using recovered heat to raise the temperature of an incoming fluid can reduce the additional energy required to reach the target processing temperature.
Recovering heat from the treated fluid can also reduce the thermal load on downstream cooling equipment, depending on the process configuration.
Heat recovery must be incorporated without compromising required treatment temperatures, holding times or other critical process parameters.
The availability of waste heat does not necessarily mean it can be recovered efficiently or economically.
The feasibility of heat recovery depends on the fluids involved, temperature differences and the way the installation operates.
The temperature difference between the fluid streams, their flow rates and changes in operating conditions determine how much useful heat can be transferred.
Viscosity, composition, suspended particles and fouling potential all influence heat exchanger selection, thermal performance and maintenance requirements.
Continuously operating systems may offer different heat recovery opportunities from equipment running intermittently or in batches.
Operating hours, production schedules and the availability of hot and cold streams should therefore be considered.
Depending on the application, equipment design must account for the risk of cross-contamination, cleaning requirements and the need to keep process streams separated.
ACTITUBE® is ACTINI's tube-in-tube heat exchange technology. Depending on the process configuration, it can be used for heating, cooling or heat recovery. Its suitability depends on fluid properties, operating temperatures, heat transfer requirements and cleaning constraints.
Continuous thermal effluent decontamination systems can recover heat between different stages of the treatment process. Selected ACTINI equipment ranges, including FDS, incorporate heat recovery stages designed to reduce the external energy required for treatment.
Heat recovery can also be considered in batch treatment systems, where heating and cooling take place during successive operating phases. The recovery arrangement depends on the equipment design, cycle requirements and available heat sources. The Actini ULTIBATCH range can include an optional heat recovery section.
The benefits of heat recovery depend on the equipment configuration and actual operating conditions.
A technical assessment should consider:
These inputs can be used to develop a heat balance and estimate the energy demand of an installation with and without heat recovery.
Potential savings should always be evaluated against clearly defined assumptions and realistic operating conditions.
Heat recovery is easier to evaluate when energy requirements and process constraints are identified during the initial engineering stages.
Actini Group can assess opportunities to incorporate heat recovery into new thermal processing equipment or, where technically feasible, as part of a modification to an existing installation.
The assessment can take into account process characteristics, available utilities, installation space and operating constraints.
In industrial process engineering, both terms generally describe the capture and reuse of available thermal energy for another heating or preheating requirement.
Heat recovery is the more commonly used expression in this context.
No. Feasibility depends on operating temperatures, flow rates, process configuration, operating schedules and technical constraints.
Some installations do not have the necessary conditions to make heat recovery practical or economically worthwhile.
Yes. Indirect heat exchangers transfer energy across a separating surface without intentionally mixing the fluid streams. However, the appropriate exchanger design and measures to manage cross-contamination risks depend on the application and its process requirements.
There is no universal percentage. Potential savings depend on temperature differences, flow rates, exchanger performance, equipment design and operating conditions. A process-specific heat balance is needed to estimate achievable savings.
In some cases, yes. A retrofit assessment should consider available temperature levels, space and piping arrangements, utility connections, hygienic requirements and the potential impact on process operation.
