At Kuhlman Incorporated, we have decades of experience managing the design, construction, installation, and servicing of mechanical refrigeration systems. This expertise gives us the insight needed to develop solutions that meet and overcome various refrigeration challenges. One such case that tested our ability to design, develop, and deliver effective and efficient refrigeration systems is outlined below.
The Challenge
A soft drink manufacturer and distributor approached our team with a request for a more efficient compressor room design to justify the receipt of an $104,000 grant from the local Utility Company.
The existing system consisted of the following components:
- Allen Bradley PLC unit. The system uses high-pressure liquid to feed out to the loads in the plant, which necessitated the use of a discharge pressure control system to ensure adequate pressure was maintained. An Allen Bradley PLC controlled the compressor discharge pressure – starting and stopping the system’s condenser fans and pumps to maintain 175 psig or 93º F condensing pressure – and the suction pressure – turning the compressor on and off in rapid succession to maintain 20 psig or 5º F suction setpoint.
- Seven Vilter 448 reciprocating compressors. Each compressor operated with a suction temperature of 5º F and a condensing temperature of 93º F to achieve refrigeration capacities of up to 63 tons. This design resulted in a total system compression capacity of 441 tons of refrigeration. Since the system’s load was 361 tons of refrigeration, the system had only 80 tons of reserve capacity.
The Solution
After evaluating the facility’s refrigeration load requirements and considering the higher energy efficiency requirements, our team came up with the following compressor room design:
- Allen Bradley PLC unit. The new system design uses pumped liquid to feed out to the loads in the plant. This change eliminates the need for strict discharge pressure control. Instead, the system incorporates a floating discharge control system that allows discharge pressure to float between 150 psig (or 85º F) and 103 psig (or 65º F) condensing temperature. Similar to the existing system, the new system uses an Allen Bradley PLC. However, this PLC has custom programming that takes into account system loads and outdoor weather conditions to adjust the discharge setpoint. This ability allows the facility to maintain the discharge pressure to more precise levels from day to day.
- Two Vilter VSSC-751 screw compressors with VFD control. These compressors operate at suction temperatures of 28º F and condensing temperatures of 85º F, giving each a refrigeration capacity of 361 tons. Their much higher performance capabilities decrease the number of units needed and increase the system’s overall refrigeration capacity to 722 tons with 361 tons of reserve capacity.
The Result
Our proposed design overcame all points of the challenge. It met and far exceeded the refrigeration capacities required and provided more streamlined and efficient operation. Once completed, it saved significantly in energy costs.
Quality Refrigeration System Solutions
The case study described above is representative of the quality of the system optimization and retrofitting solutions we provide to our clients on a regular basis. Our extensive experience working with mechanical refrigeration systems makes us an ideal partner for any industrial refrigeration needs. To learn more about our refrigeration system capabilities or partner with us on a refrigeration system project, contact us today.
Partner With the Refrigeration Experts at Kuhlman Incorporated
Equipped with decades of industry experience, our team has the expertise to fulfill any refrigeration system need for new, refurbished, or existing equipment. By ensuring our customers’ systems are optimized and efficient, we provide them with significant savings regarding time, investment, and energy costs.
Whether you require custom design-build assistance, troubleshooting, maintenance, repair, or training, we’ve got you covered.