Abstract: A process for conversion of a first refrigeration system including a first medium temperature circuit and a first low temperature circuit configured to circulate a synthetic refrigerant to a second refrigeration system includes replacing the first low temperature circuit with a second low temperature circuit by adding a heat exchanger to the first refrigeration system such that the second low temperature circuit is in a heat exchange relationship with the first medium temperature circuit, replacing a condenser of the first medium temperature circuit with a gas cooler, and connecting the second low temperature circuit to the first medium temperature circuit via pipe connections such that the low temperature compressor is fluidly connected to a medium temperature compressor of the first medium temperature circuit.

Abstract: The present invention is an improved dry ice pellet manufacturing system including an automated helical injection system, a chamber having a greater filter screen ratio than prior art designs and a compressing mechanism. The automated helical injection system enables injected CO2 to follow an approximately helical path inside the extrusion chamber, such that CO2 snow begins to form, and is packed, at the die end of the chamber. The automated injection subsystem provides maximum ice production, the present system utilizes both staggered injection rates and a valve arrangement that improve (increases) upon the amount of CO2 injected into the extrusion chamber over time. The present invention further utilizes a chamber having a greater filter screen ratio than currently is used in the art. The extrusion chamber of the improved pelletizer of the present invention has approximately a 35% or greater filter screen ratio; filter screen ratio being defined as the ratio of filter screen area to chamber bore area.

Abstract: An improved dry ice pelletizer and method for significantly increased pellet production. The improvement consists of multiple injection ports used for the timed introduction of liquid carbon dioxide into a dry ice extrusion cylinder so that the cylinder can be more completely filled with carbon dioxide snow before extrusion takes place. Part of the improvement stems from the use of a solid mass of carbon dioxide, called a puck, which is chamfered and serves to capture carbon dioxide vapor and snow within the compression cylinder. The resulting improvement in carbon dioxide pellet output is roughly 400% over that achieved by conventional methods. The inventive improvement may also be installed as a retrofit to conventional dry ice pellet extrusion machines.