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ammonia21.com talked to Marcos Braz, President of MRBraz & Associates, and member of the IIAR Board of Directors. Having over 28 years of experience in refrigeration engineering, Braz explains the challenges of a project in Haiti, priorities in ammonia system design, as well as what could help bring ammonia to developing countries.

ammonia21: What exactly are you planning to do in Haiti? Can you explain in detail the kind of applications planned?

Braz: In Haiti, we worked on a request for the design of an block ice plant of 600 ice blocks /day of approximately 400 pounds each. We felt that there was a need for integration of the refrigeration system to meet the client requests. We tried to help the client with the design technology that apparently they did not have.

ammonia21: So what you just described was a project that you were working on before the earthquake. But now that the situation has changed tremendously in terms of infrastructure, how do you see this system helping the reconstruction of Haiti?

Braz: I think this refrigeration system will be very useful because it brings the ability to preserve food on a very simple to operate system with a lot of potential for creating immediate impact on producing ice for different functions. Those ice blocks can hold a lot of Btus on them and they are easy to be sent from place A to place B. I think this project will help to put in place some structure to preserve food in Haiti.

ammonia21: What are the technical challenges posed by this new project?

Braz: We did not have any drawings to understand the layout or structural elements and hence how the system would fit around the facility per se or the building. So we had really to make things compact and try to understand through descriptions by phone how things are there. All this adds complexity.

So we did not have the formal “send me your building drawings” and all these reference documents we are normally used to. You have to make assumptions and try to “read” the project through the telephone - not easy at all.

ammonia21: Besides the technical side, what do you find to be the most challenging task in your new project in Haiti?

Braz: Communication. Even before the earthquake, there were difficulties with phones and lines. With the earthquake communication just disappeared, it leveled. So you have zero communications. After the earthquake we had communication through satellite. The facility’s owner made a huge effort to cope with the disaster and tragedy and at the same time keep in focus and continue with this project that ultimately benefit the industry and people in Haiti.

ammonia21: Why ammonia, why a natural refrigerant?

Braz: I have an appreciation for this natural refrigerant. It is an abundant resource, it is self alarming, it is the future, it has all the benefits. I have been working in other countries besides US, such as Mexico and Brazil and you can always tell that people associates ammonia as a toxic refrigerant and so forth. People fear it, but I always start by reassuring them that we have the best detectors for ammonia, namely our noses. So if you have a plant with 300 employees, you have 300 detectors. It is important to note that just below 25ppm ammonia’s concentration is largely noted. Very far (about 20 fold) before will cause any permanent harm to an individual (500 PPM IDLH).

It is, self alarming, abundant, extremely efficient for carrying energy from point A to point B by using the smallest amount of mass and very manageable operating pressure. On a catastrophe scenario of, for example, loosing ammonia to a hurricane , basically you are just bringing back to nature what was of nature’s. Unlike, halocarbons (zeotropics and azeotropics) or frequently called “freons”, there is no impact to the environment.

ammonia21: You have close to 3 decades of experience in refrigeration engineering, starting off in Brazil. Why did you decide to focus on ammonia refrigeration?

Braz: Going back 30 years I started with food processing, I would say that energy performance was the first factor towards working with ammonia. In the US I had the opportunity to join the International Institute of Ammonia Refrigeration (IIAR) and that brought in a new vision towards this refrigerant and its impact on the environment. Since 1992 the Montreal Protocol has brought really a lot of attention to other refrigerants. Then I started to research further looking at the future, as I saw the refrigeration industry prospering. I have been supporting the idea of ammonia as the refrigerant of choice ever since.

ammonia21: Can you tell us more about your patented multiple-stage recirculating single-feed refrigeration system already installed in more than 10 facilities? How does this help to optimise efficiency, increase safety or lead to other benefits?

Braz: As you increase capacity of refrigeration, you would like to not just scale a lot more equipment, more horsepower with additional proportional refrigerant charges. So we tried to minimize piping and equipment sizes - a general trend in the market. It was a large refrigeration system, and we had to come up with something that did not look like a linear scale of the capacity versus equipment and charge. So we optimized the system’s equipment to achieve lowest initial capital cost and at the same time creating a very safe to operate system with liquid level self management. Meaning that any disturbance on the liquid levels that could put in risk compressor operation and therefore product safety, was automatically corrected avoiding unnecessary and prolonged shutdowns. Basically the multiple stage refrigeration system would understand “I am getting out of balance, I am going to balance myself” – quite an intelligent system.

ammonia21: Ammonia is still often sidelined by industry and policy because of safety concerns, in particular toxicity. How important is the safety aspect in your work and the activities of the whole ammonia refrigeration industry? How to make sure that a high safety standard is maintained at any time - which are the critical elements?

Braz: In my area of expertise – engineering refrigeration systems - you have to establish the priorities and design criteria. I think that the label of toxicity for ammonia is desirable, as it points out the fact that you have to be careful and focused. A good refrigeration system design needs to follow three principles, namely 1. It has to be safe; 2. Product integrity has to be respected;
3. The system has to be Energy efficient. If you make these your priorities – safety, product integrity and energy optimization - you will be very fine!

Hence, we are always trying to bring the industry to line up these priorities: You should not talk about energy savings if you do not have a safe operation. You should not talk about energy savings if you do not have a system that can sustain the temperatures desired for your product to reach the market. So you need all three pillars and stack them in priorities. The most important regarding ammonia is safety. Safety sustains everything: without that one you will not have the other two.

ammonia21: Why is ammonia so popular in the US and beyond? What factors have made it a success?

Braz: This goes back to energy efficiency, environment friendly and abundance of ammonia. You can bring ammonia technology to your customer with confidence. Larger refrigerated facilities looking for decades of operation and future expansions don’t have to worry about replacing this natural refrigerant while achieving lowest energy costs to operate. You will be making improvements but you will not have to worry about making a radical change in your refrigerated facility.

ammonia21: How wide-spread is ammonia in the US refrigeration industry, which market share does it have among all industrial refrigeration applications in the country?

Braz: I do not have a precise number but my feeling on this is that the market share of ammonia in industrial refrigeration systems in USA above 300 TR should be close to 95%.

ammonia21: What could be driving factors to establish ammonia refrigeration also in developing countries, from a technology, policy and industry point of view? What are the major barriers?

Braz: Mainly education. From governments, to end-users and operators, there is a lot of misconception. I have had the opportunity to work with authorities in Brazil, Mexico, and Japan and you can see the main issue is a question of understanding what ammonia refrigeration represents and not merely reaching conclusions by just labeling this very natural and environmental friendly refrigerant as toxic. We have a tendency to put a label on things and shy away from understanding what is behind - ‘label and bye’.

We need to promote ammonia in countries where there are opportunities for misconceptions. As you sit down to discuss with anyone that has reservations about using ammonia and you lay out the facts on the table, is very common to reach understanding and consensus to the benefits of this natural refrigerant. When you show the effiiciency of this refrigerant, the safety standards that are involved in this industry, the facts speak by themselves and ultimately the conclusion is that this is a refrigerant that is very energy efficient and will not harm the environment. I had opportunities in this regard – in USA and Overseas - and I am proud to say I had not had any discussion where we could not get across the misconceptions with simply educating by showing the real benefits of ammonia used as a refrigerant. I have seen situations, mostly outside the US, where people made the wrong or perhaps a less efficient decision because they did not have access to technical information about ammonia. Thus, education is truthfully key to enhance the applications of this natural refrigerant.