Information

Permitted (O)– Carbon steel– Stainless steel– Aluminum– Other nonmetallic materials such as PTFE are permitted (if they will not break down)Source: http://www.ashrae4greenville.com/resources/Newsletter/2014/Intro-to-Ammoni-Refrigeration.pdf

Not permitted (X)– Copper and copper alloys such as brass are prohibited (but allowed for bearing materials)– Zinc (in continuous contact with ammonia)– Non-metallic materials that degrade upon exposure– Other nonmetallic materials such as PTFE are permitted (if they will not break down)Source: http://www.ashrae4greenville.com/resources/Newsletter/2014/Intro-to-Ammoni-Refrigeration.pdf

Reciprocating Compressor (Open Type) is the most common and mature compressor found in the market. Some of the popular brand in the market are MYCOM, Grasso, Vilter and Sabroe. The open type reciprocating compressor is driven by an external motor via direct drive or belt drive. The crankshaft is then move the piston up and down to generate the suction force for the refrigerant. The refrigerant vapor is then sucked into the compressor.After compressing the refrigerant to high pressure, the refrigerant (high pressure high temperature) is discharged to condenser.ADVANTAGE:1. High Coefficient Of Performance, especially during partial load2. Mature Technology3. Parts and technician are easily available4. Lower Initial CostDISADVANTAGE:1. More moving parts means higher chances of breakdown – Overhauling is recommended after 1 year of service2. More vulnerable to liquid flood back3. Relatively smaller capacity compared to Screw Compressor4. Lower Initial Cost

As per cited from Danfoss website, CVQ is an electronically operated constant-pressure pilot valve that functions together with
the EKC 361 electronic system or an EKC 366
controller. CVQ enables the electronic (and thus the remote)
control of a ICS or PM main valve.The CVQ valve is used to maintain a constant
pressure at the ICS or PM main valve inlet side
and can, via suction pressure regulation, very
accurately control the temperature of a medium
from an air or liquid cooler, etc.Today, CVQ valve is widely used in Cold Room, Palm Oil Industry (shortening or margarine plant) due to it’s fast response toward changes of suction pressure.Typical installation of CVQ valve

How common is ammonia refrigeration?

Many years ago, the food and beverage industry embraced ammonia refrigeration. The economic advantages alone made it the refrigerant of choice for cold storage facilities and food processing facilities as well as the dairy and meatpacking industries. Almost all of the food on the family breakfast, lunch and dinner table passes through an ammonia refrigeration facility before reaching your grocery store including fresh fruits and vegetables, meat, poultry and fish, frozen convenience foods, milk, cheese and ice cream, and beverages such as soft drinks, beer and wine.
How long has ammonia been used as a refrigerant?Ammonia was among the early refrigerants used in mechanical systems, and it’s the only one of the early refrigerants to secure a lasting role as a refrigerant. Mechanical refrigeration was developed in the 1800s based on the principle of vapor compression. The first practical refrigerating machine using vapor compression was developed in 1834 and by the late 1800s refrigeration systems were being used in breweries and cold storage warehouses. The basic design of the vapor compressor refrigeration system, using ammonia as a refrigerant in a closed cycle of evaporation, compression, condensation, and expansion, has changed very little since the early 1900s.When was ammonia first synthesized?Ammonia was first synthesized in 1823 by reacting air and hydrogen. The first commercial production of synthetic ammonia began in 1913. Presently, there are an estimated two billion metric tons of ammonia present in the world. Of this amount, approximately five percent is man-made. Approximately 18 million metric tons of ammonia are produced annually in North America alone, and of this amount, less than two percent is used for refrigeration.

A simple and easy understanding on the ammonia refrigeration cycle to create chilled water.https://www.youtube.com/watch?v=gtbbJpvIy9k&feature=emb_title