Simon Lang, head of sales/new pumps at HERMETIC-Pumpen GmbH, discusses the opportunities, technologies, and challenges present in the growing ammonia sector.How is the ammonia sector growing?
In 2021, around 180 million tons of ammonia were manufactured globally. We expect that the ammonia market will continue to grow, especially in the co-firing branch and tank storage sector. Roughly 75% of ammonia is being used to produce fertilizers. Various substances derived from ammonia serve as starting materials for polymers. As a fire-resistant, non-hazardous refrigerant regarding the greenhouse effect, ammonia is being used in refrigeration technology. In the quest for alternative fuels, ammonia is also increasingly brought up as a topic for discussion as a potential hydrogen carrier, as well as an alternative to hydrogen.
What types of pumps are used in the ammonia market and how?
In the ammonia market, we find conventional centrifugal pumps with mechanical seals and sealless pumps. HERMETIC only produces/provides sealless pumps. In contrast to conventional centrifugal pumps with mechanical seals, canned motor pumps do not have any vulnerable dynamic seals. Instead, canned motor pumps have a second hermetic safety containment that prevents any leakage of pumped media and emissions.
The design-based omission of wear-prone components, such as shaft seals, couplings and roller bearings, ensures a high degree of operational safety, almost negligible wear and the best MTBF (mean time between failure) values compared to other pump technologies.
What solutions does HERMETIC offer the ammonia industry?
HERMETIC offers canned motor pump technology. We can provide pumps for the chemical market, for industrial refrigeration but also for tank storage.
One example is a compact pumping solution for discharging condensed ammonia.
A HERMETIC CNF-type canned motor pump is used to discharge condensed ammonia. It is suitable for liquefied gases, boiling media and condensates with a vapor pressure of up to 10 bar. With an integrated auxiliary impeller and internal fluid return, it is suitable for conveying liquids close to vapors phase. The range of applications for CNF variants includes delivery heads of up to 220 m, flow rates of up to 1800 m³/h, fluid temperatures from -120 °C to +360 °C, power ratings of up to 220 kW and pressure ratings of up to 25 bar.
The present system uses a single-stage CNF 65-40-200 pump with a flow rate of 15m³/h and a delivery head of 45m. The N34L-2 motor provides a shaft power of 10.5kW. The operating temperature is 40°C and the vapour pressure is 1.2 bar. Thanks to internal recirculation, a partial flow for cooling the motor and lubricating the plain bearings is branched off at the periphery of the impeller and, after flowing through the motor, it is conveyed back to the pressure side. An auxiliary impeller is used to increase the pressure to prevent the fluid from changing to the gaseous state due to the pressure loss downstream of the impeller.
Conventional pumps require external recirculation ducts for this purpose. A higher risk of leakage exists in this case since more seals, flanges and pipes are required. Plus, the cost of installation is also higher. With a recirculation within the pump, HERMETIC offers a slim pump solution that requires little installation space and effort. The canned motor filled with liquid is wear- and maintenance-free during continuous operation due to hydrodynamic sleeve bearings.
Another example is the V-line modular system, which offers attractively priced CNF series pumps with standardized pump/motor combinations. This modular concept supports plant engineering with a choice of variants with different hydraulics, motor ratings and material versions, including matching monitoring technology. The range of applications for CNF variants includes delivery heads from 12 m to 145 m, flow rates from 1.5 m³/h to 130 m³/h, fluid temperatures from -50°C to +180°C, power ratings from 6.0 kW to 33 kW and pressure ratings of up to 16 bar.
What are the key challenges associated with pumping ammonia?
The physical properties of ammonia (low viscosity and density, low temperature) are a challenge for pumps. High corrosivity and the harmful or toxic property of ammonia require high material resistance and leak-proofness of the equipment used. Since canned motor pumps are hermetically sealed and offer a high level of safety, they are particularly well suited to this purpose, especially when discharging condensed ammonia and pumping liquid ammonia into storage tanks.
What do you believe the future holds for the ammonia sector?
We believe that the market will grow especially due to the energy sector and the energy transition. Pumps will have an important role because the requirements and regulations for safe production and plants will increase. Our technology guarantees no leakage for greater protection of people and the environment.
What new pump developments/technologies or approaches are being developed for the ammonia sector?
The market is asking for highly qualified canned motor pump technology for all standard ammonia applications, in particular for ammonia tank store plants, for pumps installed in tanks. Also retractable pump solutions are requested.