The Need to Reduce Industrial Energy Consumption and Recover Waste Heat
Waste heat generated in industrial processes is pure potential. With smart engineering, this potential can be harnessed to reduce a facility’s carbon footprint and energy consumption. With a typical Return On Investment (ROI) of two to four years, JOA energy recovery systems might be the easiest step you can take towards a more environmentally friendly and cost-efficient production process.
The Importance of Industrial Energy Saving
Wherever production takes place, energy is consumed and costs are incurred. The amount of energy expended varies from process to process and from facility to facility, but using less energy will always lead to cost savings while also contributing to your greenhouse gas reduction and sustainable development goals (SDG).
Excess heat can be reused in various ways. In each scenario (air-to-air, air-to-water, or air-to-steam), a closed-loop solution is preferred over other solutions. A selection matrix answers the following questions regarding each of the potential reuse scenarios:
- How much heat can be reused?
- What investment is required to capture and reuse this heat efficiently?
- What is the ROI?
- Is the heat source easily accessible, or are there physical obstacles that complicate access?
- Is it feasible to split a heat stream and reuse it in two or more secondary processes?
How to Recover Energy from Industrial Processes
The generation of electricity and steam are major cost factors in production processes and key factors in reducing a factory’s carbon footprint. The design rule that JOA generally follows to make the control system as direct and simple as possible is to make the energy provider also the consumer of the generated (recovered) steam or hot water. The Energy Recovery Scrubber skid, with its large turn-down ratio, can handle condensing exhaust air streams. Condensation is targeted to occur only within the scrubber, preventing contamination in the piping network.
Energy Assessment Before Creating an Overview of Possibilities
- Site visits
- Interviews with operators/technicians
- Airflow measurements & data collection
- Determining sensible and latent heat content for each available source
- Inspections
JOA thoroughly investigates how energy is created and which consumers are available. In many vapor extraction applications, such as (spray) dryers, the excess energy in the exhaust stream must be treated before entering the filter or scrub unit (e.g., a quench chamber). Utilizing the phase change (condensation) of the moist air could provide a great opportunity for the direct generation of steam and hot water. This can be achieved using energy recovery skids and scrubbers.
Since we both build and integrate equipment into our designed systems, we can effectively recover energy in exhaust air while ensuring a healthy industrial work environment and compliant emission levels.
Smoke Removal in Dryers, Flash Towers, Roof Structures, etc.
Smoke removal often results in an exhaust air stream with high temperatures and high absolute humidity, indicating significant energy recovery potential. A key factor for the extraction system is preventing condensation of vapors at high temperatures, as this facilitates the buildup of flammable dust in the extraction system pipes.
Occasionally, we also recommend smoke tests to determine the potential effectiveness of the existing exhaust system hood at various fan speeds.
Energy Recovery Systems That Can Be Integrated
Heat streams can be recovered in various ways:
- Closed-loop air-to-air: In this solution, the heat-carrying medium is the same in both the source and the consumer. Closed-loop air-to-air solutions are very simple to implement: heat is recovered from the source and transferred to another heat exchanger point, where air for the secondary process is preheated and used.
- Closed-loop air-to-steam: Sources with high heat content can be used to create steam. When heat is recovered at 300°C, it is possible to create high-pressure steam. Even an exhaust temperature of 100°C can be used to create low-pressure steam up to 3 bar. In regular processes, this might not seem like much, but in our experience, 2 or 3 bar is often sufficient in a closed-loop solution.
- Air-to-water: Often, heat can be recovered in inline wet scrub systems such as the JOA inline venturi scrubber. We have successfully recovered exhaust air from dryers and flash towers for direct steam or hot water. Energy recovery using this method ranges from 70% to 85%.
JOA Offers the Following Systems for Energy Saving
- Heat recovery units
- Heat pumps
- Heat exchangers
- Energy recovery scrubbers
- Efficient dust removal with Inline Venturi Washer
Design Considerations for Custom Equipment
Each JOA system is designed based on data. Thorough data collection at the beginning of the design phase leads to highly efficient systems upon delivery.
- Extraction rate and capacity
- Temperatures
- Static pressure
- Relative humidity
- Absolute humidity
- Dew point
Benefits of JOA Energy Recovery Solutions
- Custom solution: We truly understand your process.
- Highly efficient scrubbers and system designs
- Solutions for all potential heat suppliers and consumers
- We truly understand air: Top specialists in emission control and air filtration
- Capable of recovering potential energy, even from low-grade waste heat sources
- Lowest ROI time: Clear scenarios provided. Typically, our solutions have an ROI period of 2-4 years and a lifecycle that extends much further.
