Commercial chillers, provided by Technical Systems Inc., make it easier for builders to excavate any construction site.
Photo Credit: McNeil, Gray & Rice

SEATTLE — SoilFreeze, based in Seattle, provides a unique technology that can reduce time and costs during construction projects. As the only U.S. construction company specializing in ground-freezing technology, SoilFreeze provides services like structural shoring, groundwater cutoff and soil contamination remediation for health care facilities and other commercial buildings.

To get the job done, SoilFreeze relies on commercial refrigeration systems manufactured and produced by Technical Systems Inc. (TSI), a division of Pryor, Okla.-based RAE Corporation. Through the partnership, SoilFreeze has access to innovative and sustainable forms of technology that can complete projects seamlessly and in short amounts of time.

Commercial Chilling

Commercial refrigeration systems work by using a liquid refrigerant to cool evaporator tubes and absorb heat from the chilled water circulating through the machine. The chilled vapor is then drawn out of the evaporator by the compressor. From there, the compressor pumps the refrigerant vapor to the condenser, raising its pressure and temperature. The refrigerant condenses on or in the condenser tubes, giving up its heat to the cooling water (or air). The high-pressure liquid refrigerant from the condenser then passes through the expansion device that reduces the refrigerant pressure and temperature as it enters the evaporator. The refrigerant again flows over the chilled-water coils absorbing more heat and completing the cycle.

Commercial refrigeration systems allow builders to develop a waterproof barrier by freezing the ground. This eliminates the need to pump groundwater out of an excavation site and to treat and store it somewhere else. It also eliminates the risk of spreading contaminated groundwater into previously uncontaminated areas.

The process of freezing the ground before an excavation is time-consuming, but with the right technology and tools, it saves time as the excavation does not need to be stopped repeatedly in order to shore up and waterproof newly excavated areas.

Construction Sites

When working on construction sites, the first step SoilFreeze takes is installing piping vertically in the ground to form a freezing system around the perimeter of the excavation site. From there, a flow system is hooked up to these pipes in order to circulate refrigerant through a chilling system; this fluid pulls heat out of the ground and is re-cooled by the chillers continuously until the ground reaches -20 degrees Fahrenheit. This process takes between four and eight weeks, depending on soil conditions and ambient temperatures.

Once the ground reaches -20 degrees Fahrenheit, the refrigerant solution continues to circulate to maintain this temperature and keep the ground structurally sound throughout the excavation process. Excavation work ranges in duration based on the construction project, but can last up to two years or more.

“Long-term, extensive ground freezing requires extremely reliable chilling equipment and technology,” said Larry Applegate, president of SoilFreeze, in a statement. “We contacted RAE Corporation many years ago to purchase our very first chiller. Over time, we’ve continued to purchase their equipment, because they have proven to meet our needs.”

TSI has modified their commercial chillers to better meet the needs of SoilFreeze. According to a statement from Jeremy Colvard, vice president at RAE Corporation, the chillers built for SoilFreeze are designed to be loaded and unloaded with forklifts or cranes, and to be controlled remotely.

“We designed a microprocessor control system so that Larry [Applegate] and his team can remotely connect to and communicate with the refrigeration units,” said Colvard in a statement.

This article was provided by Pryor, Okla.-based Technical Systems Chilling Equipment. The company creates technologically advanced equipment used in health care facilities and other commercial buildings to improve building performance. They can be contacted at 918-825-7222.