Multi-purpose pumps for performance

Stefano Calandri, Vanzetti Engineering, Italy, studies the response to the technological evolution of engines with a view to greater efficiency and intensified deployment of LNG structures.

More and more new ships are using methane engines for their propulsion system, particularly those with high-pressure systems. This is a reversal in trend compared to a few years ago, when low-pressure systems were more common. Moreover, in the small scale industrial sector, the cryogenic pump downstream applications that have seen a significant growth in the past few years are related to gas pipeline feeding, gas power generation stations, gas peak shaving plants, and LNG transfer in small-to-medium size shore terminals. Therefore, Vanzetti Engineering has significantly increased the supply of its high-pressure pumps for the marine sector in response to the increasing demand for this type of product for marine engine fuel supply systems.

Pumps for ships

The new trend in recent years about LNG marine engines is linked to their technological development, with a growing focus on more sustainability and greater efficiency. Vanzetti Engineering was already supplying high-pressure pumps for the marine sector in 2019. However, if up until 2020, 90% of the cryogenic pumps sold for this sector were low-pressure pumps (maximum 20 bar), from the start of 2021, orders for high-pressure pumps (maximum 350 bar) have increased considerably, to the point that today 50% of orders are for high-pressure pumps and 50% for low-pressure pumps.

Since 2021, the number of orders for VT-3 reciprocating high-pressure cryogenic pumps has boomed. This is due to the new market trend towards high-pressure systems, especially for large methane-powered vessels such as container ships, bulk carriers, gas and chemical carriers, and car carrier ships. Today, large ships can be fitted with high-pressure two-stroke engines and therefore require the Duplex, Triplex, or Quintuplex versions of reciprocating pumps. Vanzetti Engineering’s VT reciprocating cryogenic pumps supplied a large number of skid-mounted VT-3 Duplex and Triplex pumps for over 30 ships with high pressure fuel systems, to customers located in various geographic areas, in particular China, Korea, Singapore, and Norway.

Fuelling vehicles

To fuel vehicles with a natural gas engine (NGV) with compressed natural gas (CNG) or LNG, the company offers customised solutions for public stations and private fleets. LNG is stored in a

cryogenic tank, which provides fuel to the high-pressure reciprocating pump. Compressed LNG is pumped through an ambient vaporiser, where it is warmed and transformed into CNG. To complete the process, the CNG is then stored in a gaseous buffer, ready for refuelling vehicles. For this type of fuelling station, the supply proposed by Vanzetti Engineering consists of:

z Reciprocating piston pump model VT1 with 800 Nm3/h capacity (or two pumps to double the flow-rate) and 30 kW electrical motor power installed.

z Cold charge group to optimise the CNG temperature and the gaseous storage efficiency (optional).

z High-pressure ambient vaporisers for vents.

z Distribution and safety panel to protect non-cryogenic components from temperatures that are too low and over pressures.

z Electrical control cabinet (optional) with remote access for web browser monitoring.

Safety, reliability, and low maintenance

The company’s VT-3 reciprocating cryogenic pumps, which evolved from the previous VT-55 model, come in Simplex, Duplex, Triplex, or Quintuplex versions depending on the flow rate required and have a maximum pressure of 420 bar. The VT-3 model is an effective solution in terms of performance, safety, reliability, and low maintenance requirements and can be provided on a skid with all accessories including sensors, instrumentation, and valves for a safe and reliable control of the pump. VT Series cryogenic reciprocating pumps offer high efficiency, compatibility with cold converter and thermosyphon storage tanks, and easy installation thanks to 360˚ rotating inlet and outlet connections. Their maintenance is quick thanks to the integrated cartridge seal system. VT Series pumps can be used in CNG refuelling stations for road vehicles and for buffer filling.

Figure 1. Submerged cryogenic pump ARTIKA series.

Figure 2. Reciprocating cryogenic pump VT-3 series.

Centrifugal multi-stage submerged pumps

With numerous marine pump projects supplied and several in its order portfolio, ARTIKA submerged pumps can be the answer to various needs for small, medium, and large LNG carriers: fuel gas pumps, spray pumps, stripping pumps, and cargo pumps. Depending on the requirements, the ARTIKA models can pump the LNG from extremely low to very high flow rates, with supplied differential pressures that can vary from minimum levels up to approximately 20 bar necessary for the XDF two strokes’ engines. For example, for automotive sector LNG refuelling stations, Vanzetti Engineering proposes the ARTIKA 160 submerged pump that can be used for one or two LNG dispensers. The ARTIKA 120-3S is the smallest pump in the series and is used in marine sector applications. The ARTIKA 200-4S can deliver a guaranteed flow rate of over 30 m3/h at 35 bar, while the ARTIKA 200-6S is able to reach a differential pressure of 55 bar.

Both models can be used for FSRU projects. In order to meet the needs of applications that transfer LNG to small and medium size terminals, the ARKITA 300 is available in a 1 or 2 stage configuration, which can reach a flow rate of up to 270 m3/h. With a flow rate of up to 546 m3/h, the ARTIKA 400 will complete the current range of submerged LNG pumps designed by Vanzetti Engineering. With the ARTIKA Series, the company is able to supply all the cryogenic pumping equipment downstream of the liquefaction plants, on skids, and complete with all the accessories, sensors, and instruments. The features of ARTIKA pumps include the seal-less concept with the motor bearings permanently lubricated by LNG, which allows a perpetual cold condition for quick and efficient starting and stopping and a low maintenance frequency due to the absence of wear parts. The ARTIKA Series submerged cryogenic pumps for LNG are available in one-stage or multi-stage configurations (2, 3, 4, or 6). They are designed to work submerged in cryostats/sumps or in cryogenic tanks and are suitable for continuous and discontinuous operations. They feature helical inducers to minimise NPSH requirements, integrated motors to be used with inverter/VFD, and low noise (<80 dB) during operations.

External centrifugal pumps

The company has developed the hydraulic gearbox motor (HGM) series to expand its range of centrifugal cryogenic pumps to be mounted on tanker trucks. This extension range allows the company to meet any type of requirement for loading and unloading road tankers. A centrifugal cryogenic pump on truck board is used to transfer LNG from the truck to the refuelling station storage tank, allowing the pressure difference between the storage tank and the tank of the vehicle to be compensated. Unlike the hydraulic direct motor (HDM) series pumps, the HGM series pumps have a hydraulic motor and gearbox transmission to take maximum advantage of the

HGM technical features. The structure of the new HGM series is particularly robust and offers a maximum operating speed of 8190 RPM, with a maximum flow rate of 950 LPM. These new types of pumps, which includes the HGM 185 and HGM 200 models, offer significant advantages: the low weight allows the unload maximisation whereas the compact design requires a small amount of space for installing. The introduction of this new series enables the company to meet the needs of those who require a cost-effective solution, while maintaining a high-level of performance and reliability.

The HGM series is an additional solution for: road trailers unloading, storage/iso-containers loading/unloading, process and back-up operations, petrochemical industry applications, special applications with differential head and flow rates upon customer demand.

HGM technical features include: hydraulic motor and gearbox transmission, mechanical seal in rulon, inducer to minimise required NPSH, low noise emission (<80 dB).

Certified quality in compliance with international standards

Vanzetti Engineering’s production process is characterised by a high level of quality combined with customer satisfaction. Over the years, the company has won several awards and certifications for its cryogenic pumps and components produced in compliance with mandatory and voluntary standards. The quality management system, which is rigorously applied, allows full traceability to each production phase. From the design and construction to the inspection and testing of each component, the company operates in full compliance with all current Italian, European, and international standards: z UNI ISO 9001 Quality Management System.

z European PED.

z European Machinery Directive.

z European ATEX Directive.

z Technical Rules of the Customs Union (EAC).

z EIGA/IGC/CGA guidelines.

z Marine Class Certifications: BV, DNV, ABS, RINA, LR, CCS,

NK, KR, RMRS.

Conclusion

Vanzetti Engineering’s goals for the future include improving its products and research and development for the devices that will equip its next-generation systems. It is therefore essential for the company to go beyond the concept of consultancy and pure sales because it is of the utmost importance to participate proactively in every realisation; in this way, it will be possible to achieve numerous advances in technological deployment, which will translate into the generation of value and benefits. The company also pays attention to the entire after-sales phase, focusing on the customer, as giving the customer the opportunity to get to know the product in-depth means enhancing the technology and being able to exploit every feature of it to achieve maximum performance.

CryoMac® 4 LNG Fueling Nozzle Maximum safety for LNG fuel technology

DURABILITY þ Ball cage interface with receptacle adapter ring guides and locks the nozzle in place for optimum engagement and user interface to increase environmental seal life.

 SAFE

“Safety Stop”

for added safety and operator protection.