Chiller and Cycling Refrigerated Dryer Pioneers: The Evolution of MTA


What do the beginnings of innovative businesses have in common? Certainly abstract attributes like creativity, intelligence and dedication all play a part, but in many cases the origins of great businesses have another, more concrete thing in common — a garage. Amazon, for instance, was originally founded by Jeff Bezos in his garage. Walt and Roy Disney made some of their first animated films in their uncle’s garage. And, last but not least, Steve Jobs, Steve Wozniak and Ronald Wayne designed the first Apple computer in a garage.

 

MTA headquarters in Tribano, Italy

MTA’s headquarters in Tribano, Italy

 

As it happens, MTA (M.T.A. S.p.A.), a globally recognized company that produces chillers, refrigerated dryers and other air treatment equipment, also started in a garage. Since its inception in 1982, MTA has grown from four partners in Italy to an international organization with 440 employees across the globe. MTA is based in Tribano, Italy, and has an assembly facility in Conselve and a manufacturing facility that spans 25,000 m2 in Bagnoli. There are also seven sales offices located in countries around the world, including France, Germany, Spain, Romania, the U.S., and Australia.

 

The MTA assembly facility in Conselve, Italy

The MTA's assembly facility in Conselve, Italy

 

In our discussion with some of the key leaders at MTA, the team at Chiller & Cooling Best Practices® Magazine learned about the history of the company, key innovations that helped drive MTA’s success, and newer products that have the company poised for a promising future.

 

Pioneering Refrigerated Air Dryer Technology

In line with other great entrepreneurial stories, MTA started with four people in a garage, along with an idea that would help change an industry. In this case, the idea was a new concept for a refrigerated compressed air dryer — the thermal mass cycling dryer.

“We got our start in 1982,” Founder and Managing Director Antonio Pengo told us. “We didn’t have any money, but we had a lot of energy. We came from the dryer industry — three of us had a background in R&D engineering, one in sales. We made two heat exchangers in our garage. For thermal mass, we used paint cans filled with glycol.”

Aside from Mr. Pengo, the other founders included Giuseppe Cassetta, Mario Mantegazza and Giancarlo Milani. They helped pioneer the thermal mass dryer, or a cycling refrigerated dryer that cools compressed air and gases using a thermal storage medium. For their design, the founders of MTA used a glycol-water mixture. In contrast to a non-cycling dryer, which runs continuously, the thermal mass dryer has the ability to shut down at a set temperature and cool compressed air with the storage medium, helping to save energy.

The non-cycling thermal mass refrigerated dryer brought MTA global recognition as a compressed air dryer manufacturer. Their innovative dryer design could handle airflows of 20,000 m3/hour at 3 bar with a huge reduction in the necessary thermal mass media (80 kg vs. the typical 800 kg). At that time, the market for cycling refrigerated air dryers was on it’s way to becoming the major market segment it is today.

“MTA has and continues to be an engineering pioneer in energy saving technologies,” said Roberto Bettin, MTA’s Director of International Sales Companies. “Innovations in heat exchangers, thermal mass media and refrigeration circuits allow us to lead the way in helping refrigeration compressors cycle OFF.”

In 1989, MTA disrupted the cycling refrigerated dryer market again. This time it was with the introduction of a patented thermal mass dryer that used silica as the thermal storage media. Using aluminum fins and a compact silica mass, the new design was capable of generating even more energy savings while maintaining the expected pressure dew point range.

 

MTA Don Joyce, John Medeiros and Angelo Mastrangelo

MTA’s Don Joyce, John Medeiros and Angelo Mastrangelo next to their just-launched DE iTECH refrigerated air dryers at the 2015 AICD Conference and Exhibit

 

MTA Enters the Process Cooling Industry

Leveraging the success of its refrigerated dryer product line as a springboard, MTA started entering other markets. In 1991, the company released a tank air-cooled hermetic compressor (TAE) designed for plastic injection molding applications. MTA’s first chiller, the RPE, offered an alternative to traditional chillers. Similar to MTA’s refrigerated air dryer ideology, the new chiller created cold water storage, enabling the compressor to turn on and off as needed rather than running continuously.

Around 1995, MTA began adopting free-cooling techniques in its chiller system designs, using separate coils for the water and the refrigerant. While this type of design started as total free-cooling, a technique that could only capitalize on the very low ambient temperatures of winter months, it has since been improved to a design that can modulate between partial and total free-cooling. When a chiller operates at partial-mode free-cooling, the energy-saving benefits can be reaped during the transitional seasons of spring and fall as well.

“Low ambient temperatures can and should be used as a “free” energy source, replacing the electricity required to run refrigeration compressors,” said MTA U.S. Sales Manager, Don Joyce. “Partial-mode free-cooling is now possible by dual heat exchanger sets using their own fans, separating the chiller and free-cooling systems.”

Additionally, MTA’s typical process cooling applications now include far more than injection molding. The company serves customers in meat and poultry processing, plastics manufacturing, metalworking, welding, brewing and winemaking.

Eight years after MTA developed its first chiller, process cooling became its largest revenue stream, encompassing a whopping 55 percent of the business. Another 23 percent of the company’s business remained in compressed air treatment, and the final 22 percent came from industrial HVAC.

 

Innovating Again — New Refrigerated Air Dryers

MTA reached its most recent milestone in early 2014, when it launched its DE iTECH refrigerated dryers in Europe (launched for the U.S. market in May of 2015). Designed to handle airflows of 10 to 1000 scfm, MTA’s new cycling dryers exploit the synergies between process cooling and compressed air treatment — namely a technique similar to free-cooling, thermal storage operation, and the exact same ambient sensors.

The DEiTECH Family of Refrigerated Air Dryers

The DEiTECH Family of Refrigerated Air Dryers

 

The DE iTECH refrigerated dryer is based on the premise that dryers are typically sized for peak demands, yet rarely need to perform at that level. With MTA’s patented Pulse Technology, a microprocessor controls the dryer and adjusts the amount of refrigerant used to correspond with actual airflow. This is in direct contrast to non-cycling dryers that work continuously, indiscriminate to the level of airflow. The adjustments to refrigerant levels are based on temperature sensors, installed in both the compressed air and refrigerant circuits.

The dryer is a three-stage module, the first of which includes the air-to-air heat exchanger. The pre-cooling designed into the system operates on the same premise as free-cooling, in that it takes advantage of existing air temperatures. As air enters the dryer, it is pre-cooled by the outgoing air in the air-to-air heat exchanger. The effect is twofold: (1) Inlet air is pre-cooled, eliminating some of the work that the air-to-refrigerant heat exchanger needs to perform, and (2) The outgoing cold air is reheated to prevent condensate from forming on the plant’s piping.

The air then enters the air-to-fluid heat exchanger where it is cooled to the required dew point by the refrigerant circuit, which operates counter flow. Water vapor condenses out of the air and is efficiently separated by the demister and removed by the condensate drain. The cold air leaving the system then re-enters the air-to-air heat exchanger where it is reheated by the incoming air, as mentioned previously.

The refrigerant circuit operates separately, but within the same unit. Refrigerant is compressed from a gas into a high-pressure liquid, and it is then injected into the air-to-refrigerant heat exchanger through a bypass capillary. The microprocessor then controls when the refrigerant moves out of the heat exchanger via a solenoid valve. Depending on the airflow, refrigerant will remain in the air-to-refrigerant heat exchanger, where it acts as a thermal mass.

 

Deitech Schematic

 

Figure 1: Air enters the system and is pre-cooled by the air-to-air heat exchanger (1). It then moves down to the air-to-refrigerant heat exchanger (2), where it is brought to an exact dew point. Air then passes again through the air-to-air heat exchanger, where it is reheated to prevent pipe sweating. At the refrigerant compressor (3), refrigerant gas is pushed through the condenser (4) where it is converted to a high-pressure liquid. That liquid is then metered through a capillary (5) into the air-to-refrigerant heat exchanger. The refrigerant stays in the heat exchanger until the microprocessor allows it to pass through a solenoid valve.  During partial-load settings, a small portion of the refrigerant will pass through a bypass capillary (7).

 

Achieving Energy Savings with Different Modes of Operation

For high and medium airflows, the dryer runs constantly, maintaining complete and reliable dew point control. The aforementioned microprocessor opens and closes a solenoid valve installed on the suction pipe of the refrigeration compressor to release pulses of refrigerant back into the refrigerant compressor. As variations in airflow occur, the Pulse Technology adjusts accordingly and compresses less refrigerant during times of lower airflow. Consequently, the compressor uses less refrigerant and consumes less energy.

For low airflows, the dryer uses thermal storage operation and cycles on and off. When the refrigeration capacity is greater than the airflow, the excess capacity cools the heat exchanger. At a specified temperature, the refrigeration compressor can then turn off, leaving the remaining refrigerant in the circuit to act as a thermal mass in the air-to-refrigerant heat exchanger. The obvious advantage is that the refrigerant compressor works much less, saving in energy costs.

The DE iTECH refrigerated dryers have a digital readout display providing the real-time information maintenance personnel need to ensure proper operation. This controller has the capability to connect the dryer to a supervisory system, like a MODBUS, for remote visibility and control.  The following statuses are always accessible from the digital readout:

  • Status of the dryer, including “off,” “dry,” and “high dew point” indicators
  • Compressor status
  • Condensate drain status
  • Level of energy savings
  • Any alarm status, including three different coded alarms, a programmable user alarm, and a general alarm contact for remote alarm indication
  • Service warning that informs facility personnel that preventative maintenance should be performed

 

Growth and Investments in the U.S.

MTA has grown substantially in the more than thirty years it has been in business. What was once a tiny operation working out of a garage in Italy, is now an international company focused on expanding its market share abroad — particularly in the U.S.

According to John Medeiros, the Managing Director for the U.S., the U.S. is a big part of MTA’s global plans, especially with the cycling air and thermal mass dryers:

“The company is currently investing the required capital in inventory and human resources in order to expand,” said Medeiros. “We are supporting our chiller OEMs and compressed air sales channel partners with very significant levels of inventory in our Buffalo (New York) area warehouses.”

Medeiros added that he believes the release of the new DE iTECH refrigerated air dryers in the U.S. market will further stimulate company growth.

The synergies within MTA’s three key business segments — process cooling, compressed air treatment and HVAC — are all evident in the company’s product designs. From MTA’s innovative partial-mode free-cooling chillers to their newly introduced refrigerated dryers, all technologies are designed to run reliably and save in energy costs. The clever engineering and innovation that put MTA on the map has the company poised for another thirty years of success.

 

MTA employees at the company's 30th anniversary event

MTA employees at the company's 30th anniversary event

 

For more information, contact Don Joyce, MTA U.S. Sales Manager, tel: (716) 693-8651 or visit www.mta-it.com.

 

To read more about Cooling Technology, please visit www.coolingbestpractices.com/technology