Category Archives for Evaporator

Plate Type Evaporators

The plate-type of evaporator is the version of liquid chiller gaining most rapidly in popularity. It is an outgrowth of the plate-and-frame heat exchanger which has been applied in the food industry for many decades. The plate-and-frame heat exchanger consists … Continue reading

03. May 2018 by Jim
Categories: Evaporator | Comments Off on Plate Type Evaporators

Sprayed Tube Liquid Chillers

In the concept of spray chillers, as shown schematically in Fig. 6.62, rather than immersing the tubes in liquid as is done in the conventional shell-andtube evaporator, liquid refrigerant from a circulating pump is sprayed over the tubes. The operating … Continue reading

03. May 2018 by Jim
Categories: Evaporator | Comments Off on Sprayed Tube Liquid Chillers

Shell And Tube Evaporators

In shell-and-tube evaporators the boiling refrigerant chills a liquid such as water or a brine/antifreeze. Some of the major forms of construction include: (1) refrigerant boiling in the tubes chilling in the shell the liquid flowing across the tube bundle … Continue reading

03. May 2018 by Jim
Categories: Evaporator | Comments Off on Shell And Tube Evaporators

Antifreeze-Sprayed Coils

An approach to controlling frost on low-temperature coils is to spray the coil with an antifreeze, such as ethylene glycol or propylene glycol. A characteristic of this equipment is that it generally provides a higher ratio of latent-to-sensible heat removal … Continue reading

02. May 2018 by Jim
Categories: Evaporator | Comments Off on Antifreeze-Sprayed Coils

Direct Expansion Ammonia Coils

Some veteran industrial refrigeration practicioners will state flatly that direct expansion should never be used with ammonia. This absolute condemnation of direct expansion for ammonia air coils should be challenged, because some of the unsuccessful attempts of the past can … Continue reading

02. May 2018 by Jim
Categories: Evaporator | Comments Off on Direct Expansion Ammonia Coils

Aluminum Versus Steel Coils For Ammonia

Section 6.9 has already listed the most popular choices of materials of construction for air coils, including copper tubes and aluminum fins for halocarbon coils and steel or aluminum for ammonia coils. Both all-steel galvanized coils and allaluminum are widely … Continue reading

02. May 2018 by Jim
Categories: Evaporator | Comments Off on Aluminum Versus Steel Coils For Ammonia

Water Defrost

The second-most-popular method of defrosting industrial refrigeration coils is by spraying water on the coil, although the method is a distant second to the popularity of hot-gas defrost. Water is sprayed over the coil and the mixture of water and … Continue reading

02. May 2018 by Jim
Categories: Evaporator | Comments Off on Water Defrost

Procedure For A Safe Hot-Gas Defrost

Because of the high incidence of damage in recent years to industrial refrigeration plants attributable to hot-gas defrosts, the recommended procedures are now more tightly prescribed. The critical times are at the initiation and at the termination of the defrost. … Continue reading

02. May 2018 by Jim
Categories: Evaporator | Comments Off on Procedure For A Safe Hot-Gas Defrost

Provisions External To The Defrost Control Group

The defrost process impacts the system beyond the confines of the coil itself and its associated defrost piping. For example, many plant operators maintain an artificially high condensing pressure, even when ambient conditions would permit the condensing temperature to drop, … Continue reading

02. May 2018 by Jim
Categories: Evaporator | Comments Off on Provisions External To The Defrost Control Group

Hot-Gas Defrost

When defrosting an air coil using hot gas, the basic procedure is to interrupt the supply of liquid refrigerant to the evaporator, restrict the outlet of the coil, then supply high-pressure vapor. The interior of the coil then achieves a … Continue reading

02. May 2018 by Jim
Categories: Evaporator | Comments Off on Hot-Gas Defrost

← Older posts