GROUND FREEZING: THE USE OF LIQUID NITROGEN SYSTEMS CONVERTED TO BRINE

摘要

There has been a trend in recent years in performing the initial formation freezing using liquid nitrogen(LIN) and then converting the system to circulating refrigerated brine. While proponents of this methodstate it decreases freezing time, it can also be considered an alternative to inadequate refrigeration capacity.This method was used on several small projects in the 1980s. Problems such as broken pipes, frozen brine,and unsafe work conditions caused contractors to re-think the method. This paper discusses these problemsand also presents work schedules showing no schedule reduction. In fact, this method can lead to longertime as well as significantly higher costs.