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Implementing Advanced Energy Recovery Technologies
Spray dryer energy recovery systems are designed to capture and reuse the waste heat generated during the drying process, which can significantly improve energy efficiency and reduce costs.
Calculating ROI for Advanced Energy Recovery Systems
When installing an energy recovery system, it’s essential to take a holistic approach, understanding that “you invest once and benefit for years to come.” If your budget allows, choosing the more advanced solution is wise.
The cost per kW recovered is inversely related to the system’s efficiency, making a multi-stack system the best option, from an ROI perspective.
Meet The Engineer
Calculating the ROI period for each specific installation involves considering several key factors:
- Energy source cost
- Dryer process design (determining the optimal location for the inlet recuperator)
- Space management (assessing whether there’s enough space inside the factory or if equipment needs to be installed outside)
- Floor load rating (ensuring the floor can support the system’s weight)
- Additional pressure drops for the fans
- Plant downtime for installation
- Sustainability goals
- Other relevant factors (e.g., maintenance requirements)
There are many ways to configure an energy recovery system, but each design decision impacts energy utilization.
For the inlet recuperator, the most common location is as a pre-heater for the dryer’s main air. However, when the dryer process includes a sorption (or desiccant) dehumidifier, the recovered energy might be better used elsewhere in the system. In some cases, no inlet recuperator is installed, and the recovered energy is utilized elsewhere in the plant. In colder climates, this energy can be effectively used in a “winter heater” arrangement.
For the outlet recuperator, both vertical and horizontal installations are possible. However, horizontal installations require a higher investment due to the need for multiple CIP arrangements. Vertical installations can be designed for either air direction, allowing optimal integration into the process design.
Operational hours vary based on the exhaust system design. To optimize CIP costs, outlet recuperators are designed to operate for multiple dryer cycles. The plant’s policies determine the CIP sequence, which typically begins when the pressure drop reaches a set limit. The operational hours depend on whether the exhaust system includes cyclones, a wet scrubber, or a bag filter.
Expected Recovery Percentages:
Single-stack: 15-20% recovery
Multi-stack: 40-45% recovery
With these recovery percentages, installations generally achieve an ROI in less than three years and, in some cases, around one year. The incremental cost for a new dryer installation is relatively low when all factors are considered, making the investment highly favorable.
There is obviously much to consider when thinking about installing energy recovery technology. Work with one of our engineers, who will fully assess your plant’s unique situation to recommend the appropriate system for your facility. Call 410-822-6900 or send email to problem.solved@caloris.com.
Stay tuned for part 3 — Cost Benefit Analysis of Different Energy Recovery Technologies…