Contact me


email: denkmann@nhtres.com

A website dedicated to advancing the art and science of ammonia refrigeration
         
Home

About DTS

PSM audits

How does Ammonia Refrigeration Work?

How does Ammonia Refrigeration Differs?

Downloads

Contact me

 
 
 
 
 
 

What is this website, NHtres all about and whos website is it?

 

Finally, after way too many years, I have been dragged into the computer age, more specifically the Age of the Internet.  This is my website, one I have set aside for the common good of our societies as prescribed in Scriptures.  The common good I speak of is the advancement of the art and science of ammonia refrigeration.  Because this site is open to all who may wander in, many will wonder "What is ammonia refrigeration and why a website about it?"  Since this sentence contains two questions, Ill address the second before the first. (more)


Why Ammonia?

 

First of all, why ammonia as a refrigerant? Don't we have other choices? Yes, many. The Handbook of Fundamentals, published by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) lists over 100 different fluids that can be used in a vapor-compression refrigeration system (or unit). Because refrigeration is used in so many different fields, I am going to limit my discussion to food processing. In this arena, our refrigeration systems become very large. A typical (if this is possible!) food processing facility may have enough refrigeration capacity to provide air-conditioning to several thousand homes. When working with very large systems, refrigerant compressors also become large - 1,500 hp in a single compressor motor is not at all uncommon. (more)


History of NH3 as a refrigerant

 

Ammonia first came into commercial use in the mid-1850's and began to take hold in the late 1890's. As our nation turned into the 20th Century, ice harvesting was the largest single employer group in the U.S. at the time - more people were employed cutting ice out of lakes and rivers than any other type of job. An unusually warm winter occurred during the late 1880's - natural ice became scare and had to be imported from Europe at great expense. Natural ice, regarded by many at the time as 'God's ice', precluded many people from purchasing the new 'synthetic' ice. However, this marked the beginning of ice production using new-fangled machinery at the time: an ammonia refrigeration system. Companies such as Henry Vogt Machine (boilers came along first followed by ice machine in the 1930's), Vilter, Frick, Wolf-Linde et al got started right about this time as the demand for ammonia refrigeration ice-making machinery mushroomed.

 

Whats NHtres all about?

 

NHtres.com is a website dedicated for your use hopefully and eventually to become the "home" page for people working in ammonia refrigeration (besides the news sites, etc).  Do you have a topic youd like to discuss among others in this industry?  You can post it here on the discussion page.  Need help with a head scratcher?  Youve come to the right place you can post it here also.  Im always available for consultation and will respond to questions you pose to me on this site, however be aware that the discussion page is open to every visitor.  If you have something youd rather not be posted here, you can email me. (more)


Ammonia Refrigeration Systems

 

Large refrigeration systems are just that - large, often containing thousands of cubic feet of internal volume. Most of this volume is contained within heat exchangers (evaporators, condensers). Next on this list come vessels - on both the high and low system sides. These vessels and heat exchangers must be interconnected with piping - this too adds volume. So after we add up the volumes of all connected components, we have to put refrigerant into the 'whole'. As a rough average, somewhere around 25% to 33% of the total system volume is taken up with ammonia in its liquid state. The balance of the system has vapor in it. (more)

Fig 1 Compressor it is here that cold ammonia vapor returning from the freezer evaporators is recovered, compressed and sent off to condensers for reliquification.

 

website design and promotion: Web Design Chicago