Rory Pasquariello

A consortium led by Mitsubishi Power, a subsidiary of Mitsubishi Heavy Industries (MHI) group, has completed the construction of an integrated coal gasification combined cycle (IGCC) plant in Iwaki, Fukushima, that was followed by the formal handover to the customer, Nakoso IGCC Power GK.

Operation of the new facility, which is a commercial power plant incorporating coal gasification technologies, got underway on April 16. Mitsubishi Power manufactured the core air-blown IGCC system, including the coal gasification furnace. The project called for creation of the world's largest IGCC configuration, roughly twice the scale of the Nakoso Unit 10 (former IGCC demonstration plant) completed earlier. This is the first domestically developed air-blown IGCC system of such large scale in commercial use. Compared to the Unit 10, power generation efficiency has been substantially enhanced reaching 48%, which was enabled by the gas turbine's having a higher combustion temperature.

In this case, the IGCC plant adopts a high-efficiency “combined cycle” methodology. Coal is gasified in a gasification furnace at high temperature under high pressure; sulfur, ash and the like are separated out and removed; and the refined gas is used as fuel to drive a gas turbine. In this configuration, the gas turbine is combined with a steam turbine that operates using the steam generated by a waste heat recovery boiler fueled by waste gas. Compared to conventional coal-fired power plants, IGCC plants provide greater power generation efficiency and help to reduce carbon emissions. For these reasons, they do respond to the needs of power providers in their efforts to make effective use of resources while simultaneously protecting the environment.

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Nakoso IGCC plant complete in Japan, to support Fukushima recovery

The latest Asia Turbomachinery & Pump Symposium (ATPS) aired virtually in February of 2021, a sister show to the Turbomachinery & Pump Symposium, organized by Texas A&M’s Turbomachinery Laboratory.

A jam-packed schedule touched on topics such as centrifugal compressors, gas turbine (GT) performance, combustion, additive manufacturing, turbomachinery in refineries, and operations & maintenance.

Ben Gunn and Rainer Kurz, both Managers at Solar Turbines, and Klaus Brun, Director at Elliott Group held a session on applications for centrifugal compressors, drivers, and gas turbines in the oil and gas industries. They discussed the types of equipment favored for use cases such as gas and oil wells, pipelines, storage, gas gathering and export compression, enhanced oil recovery, recycle compression, and refrigeration. As well as typical operating requirements they touched upon process behavior, dynamic behavior, and how to handle long and short-term process changes.

The speakers also discussed rotordynamics and defined limits for speed, pressure, and the number of impellers. They offered examples of driver performance characteristics to consider in gas turbine operation, including power as function of ambient conditions and the power output at various output speeds.

Kurz and Brunn were later joined by Bernhard Winkelmann, Director of Technology and Gas Turbine New Product Development at Solar Turbines in a gas turbine tutorial. They laid out the ideal operating conditions for gas turbines, real-world applications, and the controls and condition monitoring systems required to ensure safe and efficient operation.

"Site elevation, relative humidity, ambient temperatures, drive speed, fuel type, and load conditions must all be considered in gas turbine operation."

Site elevation, relative humidity, ambient temperatures, drive speed, fuel type, and load conditions must all be considered in gas turbine operation. Changes in ambient temperature impact full-load power and heat rate, as well as part-load performance and optimum power turbine speed. In addition, they mentioned the peculiarities of single-shaft and dual-shaft machines, as well as methods used to collect performance data for trending and comparison purposes.

Speakers from Solar Turbines presented at a later session on compressor station optimization. They highlighted the challenges involved in the interaction of multiple machines in a compressor station, the multiple services running within a station, and dealing with multiple stations along a pipeline. Optimization efforts centered upon fuel consumption, maximum throughput, minimum emissions, and lengthening maintenance intervals. To gain optimal performance, interactions of multiple machines should be considered on a component, station and system level, said Kurz.

Many new pipelines, in turns out, start out with 50% capacity or less and grow to full capacity over the years. Speakers helped attendees understand the various growth scenarios that might increase pipeline capacity and their repercussions. Single-stage compressors, for example, might have to be replaced with two-stage compressors. Alternatively, compressors may have to be installed in series to meet higher-

The show must go on: Takeaways from 2021 ATPS

Turbomachinery International interviewed Rod Christie, President and CEO, Turbomachinery and Process Solutions, at Baker Hughes.

We’ve completed all three LM9000 string tests for power generation and mechanical drive for the Arctic LNG 2 project.

Part of the package is on its way to be deployed at the Arctic LNG project. The tests showed that it is the most efficient simple cycle gas turbine in the world.

Our high-pressure ratio compressor (HPRC) provides increased tip speed and better head capability due to high-speed, high-efficiency impellers on a stacked rotor. The parallel shaft gear gives a nine times better gear ratio compared to epicyclic technology. The HPRC has optimized inlet and outlet flanges for a single-casing design. We reduced the number of stages so we could locate all three sections in one body. It provides a footprint reduction of 50% and has 30% less weight.

We are seeing a lot more attention on carbon capture. The next two or three years will see greater adoption of carbon capture, utilization, and storage technology. We are currently engaging in more than 20 projects globally that are in various stages of development.

 offers many opportunities for turbomachinery. It must be compressed to between 1500 and 2000 psi to be transported. Purpose-built pipelines are also needed as CO

 is corrosive. It can also be stored in old oil & gas reservoirs, unminable coal seams, and in saline reservoirs, as well as being used in enhanced oil recovery.

How active is the hydrogen turbomachinery market?

Later in the year, you should see some actual physical progress from a project perspective. We expect to see, both from a compression and turbine standpoint, projects move forward. We are waiting on some final investment decisions. Hydrogen projects will happen with greater frequency over the next two or three years. But they will be limited to specific applications and geographies. We anticipate niche rather than broad adoption. Transportation and high-end heating applications that harness hydrogen should gain broad adoption towards the end of the decade.

How will hydrogen impact the future of turbomachinery?

Investments in gas turbine technology today will be largely geared toward either switching to hydrogen or operating on a hydrogen blend in the future. That will generate plenty of orders for turbomachinery for some years to come.

But in any case, natural gas remains a destination fuel, not just a transition. The industry will be engaged in further slashing emissions. Sustainable applications of renewable gas are about two decades out. If we switched to hydrogen today, most of the population couldn’t afford it. So we need to rely on other fuels in the meantime, including transitioning from coal to gas.

 Rod Christie, President and CEO, Turbomachinery and Process Solutions, at Baker Hughes[/caption]

Q&A with CEO of Turbomachinery and Process Solutions at Baker Hughes

Just how important is software to the field of turbomachinery? This anecdote provides some insight:

In the summer of 1982, software monitoring a Siberian natural gas pipeline commanded the system to run a pressure test at a dangerously high pressure.

“It was a huge explosion. The Air Force thought it was a 3-kiloton blast,” wrote Thomas C. Reed, a former Air Force secretary who served in the National Security Council, in his 2004 memoir, “At the Abyss: An Insider’s History of the Cold War.”

According to Reed, the CIA planted the code in monitoring software it knew Russia would steal. The code ran fine for months until it triggered the blast, which resulted in no deaths. The story remains disputed, especially by former Russian intelligence officials. True or not, it shows that computer technology creates efficiencies valuable enough to steal and how the software can make or break your turbomachinery.

Computer software has come a long way since 1982. It is used to design new parts, monitor the condition of assets, analyze turbomachinery performance, and automate many functions formerly performed by people. The benefits of a digitalized, software-driven world for turbomachinery include the capacity to handle large amounts of data. Now, engineering teams can run larger, more complex simulations using cloud services and pass data seamlessly between teams.

"The benefits of a digitalized, software-driven world for turbomachinery include the capacity to handle large amounts of data."

Design engineers are increasingly using such simulations to bring their designs to market faster and make them greener and more efficient. The design cycle is shortening as technology improves and competition creates little margin for error. For gas turbines, simulation will be key to success of new fuel types such as hydrogen.

The internet is another factor that has risen the profile of software in turbomachinery. Every new product today connects to the internet in one way or another. Like many industries, advantages come to those who can use that data to create better products in the future. Real-time monitoring, for example, helps companies accumulate huge amounts of data that can later be mined to improve current products and improve future designs.

New technologies incorporated into turbomachinery include 3D printing or additive manufacturing (AM), artificial intelligence (AI), machine learning, big data, digitalization, and the internet of things (IoT). Turbomachinery specialists such as Concepts NREC, SoftInWay, Woodward, Siemens Energy, Mitsubishi Power, CFTurbo, Third Wave Systems, Emerson Automation, Open Mind, Howden, Baker Hughes, and GE Gas Power are among the leaders in advancing software and digitalization.

OMNIS by Concepts NREC is a user interface for all the company’s software that is in common with Numeca CFD.

Concepts NREC offers a suite of tools starting from preliminary design through full 3D computational fluid dynamics (CFD), finite element analysis (FEA), and 5-axis machining of turbomachinery. Together, the system is called the Agile Engineering Design System. The company also co-developed a new system called OMNIS with Numeca International. OMNIS is a user interface for all of the company’s software as well as Numeca’s CFD tools so the user can stay in a single environment for all design and analysis tasks.

“Design engineers are considering manufacturing earlier in the process,” said Dr. Peter Weitzman, President, Agile Engineering Software at Concepts NREC. “Many designers work hand in hand with manufacturing counterparts and in some cases are running 5-axis machining software themselves to ensure manufacturability early in the design process.”

Weitzman says that the turbomachinery design community has reached a tipping point where optimization is in widespread use and is a necessary part of being competitive. Thus, optimization tools must work hand in hand with design tools. Further, the optimization structure must be developed by turbomachinery designers for turbomachinery designers.

Simcenter is Siemens’ portfolio of simulation tools covering 3D CFD and FEA, 1D system simulation, and other applications. Engineers use these tools to investigate aspects of turbomachinery performance, from the early design phase to the late stages of product development. These tools enable engineers to investigate many options before any physical testing is carried out.

Simcenter tools work together, and transfer data between software and teams, speeding up collaboration. Simcenter is part of Siemens’ Xcelerator portfolio, enabling other systems to be directly integrated with simulation models.

“The digital twin for predictive maintenance is a reality for gas turbines and generators,” said Erik Munktell, Director of Energy & Turbomachinery at  Siemens Digital Industries Software.

Big data and wireless technologies have changed the way engineers design turbomachinery and the way plants use such software.

“The digital twin for predictive maintenance is a reality for gas turbines and generators,” said Erik Munktell, Director of Energy & Turbomachinery at  Siemens Digital Industries Software. “Data from turbines in operation can be fed back to performance simulations, enabling accurate predictions of component reliability. Engineers can plan for maintenance before component failure, reducing costly unplanned downtime.”

 SoftInWay AxSTREAM software is made up of various modules covering the engineering stack.

SoftInWay offers the AxSTREAM software platform for design, analysis, and optimization of turbomachinery and related systems. The platform is made up of various modules, covering the complete engineering stack, ranging from thermodynamics to aerodynamics, full 3D structural and CFD simulation, as well as

thermal-fluid systems and rotor dynamics.

“While digital twin technology is improving each day, we feel that true the digital twin is still very much in its infancy,” said Valentine Moroz, Chief Operations Officer, SoftInWay.

SoftInWay software helps engineers create a digital twin of a turbomachine or power plant and can follow its physical counterpart through the complete lifecycle from initial design specification to deployment, operation, monitoring, and servicing in the field.

Lack of data may be the largest obstacle to improving turbomachines and systems. While existing technology such as wireless sensors can help, the digital twin is going to be key in improving machine quality, performance, and operability.

OEMs are often unwilling to give up proprietary design data to end users. This can impact the validity of digital twin. SoftInWay is attempting to build enough technical assumptions into AxSTREAM to generate the data needed to create accurate digital twins.

2020 has seen a major shift in how companies think about turbomachinery design, simulation and analysis. With many engineers working from home, testing physical hardware in person has grown more difficult due to shutdown restrictions and supply chain bottlenecks. In response, companies are placing stronger emphasis on accurate and fast simulation as well as the ability to perform remotely with a geographically distributed team.

While others in the turbomachinery sector focus on monitoring and simulation software, Mitsubishi Power has a focus on the creation of autonomous power plants. The company is creating the building blocks of the world’s first autonomous power plant, T-Point 2, a grid-connected validation facility featuring the M501JAC gas turbine and the Tomoni digital software suite. Tomoni uses algorithms and massive amounts of data to conduct predictive analysis, monitor the plant’s performance, and make improvements.

The digital platform enables analytics and control systems to improve efficiency, generating more electricity with less fuel. Every aspect of plant operation is monitored and optimized.

CFturbo creates software for the conceptual design of axial, mixed-flow, and radial pumps, blowers, fans compressors, and turbines, as well as vaned stators and volutes. It supports reverse engineering, and components made with CFturbo can be exported to rapid prototyping and AM systems.

Company President Ralph Peter Mueller believes the market is growing for turbomachinery design and simulation software and related engineering services. The number of software vendors for turbomachinery design and simulation has risen, and new consulting firms have entered the market.

“We see major trends in massive CFD and FEA-simulation, including automated design exploration and optimization,” said Mueller. “Additionally, additive manufacturing makes much progress, not only for prototyping, but also for production parts. The aerospace industry drives this development. The development of new turbomachinery will be driven more and more by AI technology which can lead to reduced development cost and time.”

Third Wave Systems sells and supports Finite Element Analysis (FEA) software, and AdvantEdge machine modeling. The software helps users understand and capture data that is otherwise impossible to measure in machining tests. It provides data on stress state of a workpiece and can measure various inputs on performance.

AdvantEdge helps to reduce design iterations, simulate more designs, and adds focus to experimental results for faster decision making. As well as speeding time to market, it can help to improve tool performance by pushing tools to their limits, and analyze stress, temperature, and heat flow.

Emerson’s Ovation control platform includes analytics, digital twin, mobile and remote work, and cloud-based services. Emerson specializes in automation and uses modeling from AI and machine learning to identify impending process issues or equipment anomalies to trigger action to avoid downtime or damage. It also supports integrated vibration monitoring, generator excitation control, safety instrumented systems, distributed applications, virtualization, and digital twin embedded simulation.

Most recently, Tennessee Valley Authority (TVA) selected Emerson to modernize and optimize its Magnolia power plant. The Magnolia project is part of TVA’s five-year, $110 million investment to install digital technologies across its power generating fleet. Emerson’s software and technologies will support TVA’s efforts to digitally transform the Mississippi plant through advanced operations, enhanced cybersecurity and digital twin-enabled training.

Open Mind offers CAM and CAD software. The company’s hyperCAD-S software is meant for Numerical Control (NC) programmers conducting CAD-oriented tasks. It also sells hyperMILL, a modular CAM solution for 2.5D, 3D and 5-axis milling, and mill turning and machining operations such as high-speed cutting and high-performance cutting. Applications include milling impellers, blisks, turbine blades, tubes and tire molds.

Individual turbine blades are high-end components that have to meet many different requirements for surface quality and profile accuracy. 5-axis milling processes are commonly used in the production of impellers and blisks.

The machining of impellers and blisks places high demands on CAM software. Standard 5-axis strategies are often insufficient for NC programs to produce these components. Diffusers and casings can also be programmed with the software.

Woodward offers software designed to pair with its custom compressor and steam turbine-based controllers. The software is intended to be a plant’s standard control

platform. Woodward’s Vertex controller is designed for use on industrial-sized axial or centrifugal compressors. Standardization of controllers and related software program is aimed at saving plants in terms of the cost of spare parts and personnel training. Users can configure Vertex to function as a stand-alone control to manage and protect simple isolated plant compressors; or to control multi-function-based compressor packages with more input and output signals and integral network connections to the plant DCS.

“The use of one of these standard application programs, which are already operating and protecting turbomachinery in the field, greatly reduces the risk of a control failure and allows customers to add their own custom site-specific logic and or algorithms,” said Rich Kamphaus, Global Sales Director at Woodward. “Woodward’s new line of controllers, including Vertex, allows customers to easily view and modify control logic, interface with other plant controllers, and modify and expand hardware input/output signals or  program functionality.”

Howden provides condition monitoring and data analysis of equipment performance and processes for insight into the operation of rotating equipment. The Howden Uptime digital platform enables internet-connected products in plants to optimize operational performance. It provides real-time analysis, advice, recommendations, informed decision making, alerts for approaching failures or needed part replacements, and access to equipment documentation.

Howden Remote Assistance uses software known as Vuforia Chalk to combine augmented reality with real-time communications to connect remote product experts to on-site field technicians. The company’s Engineering Suite is a physics-based software package to model, simulate, analyze, and control the performance of process systems. It demonstrates how systems and processes behave in real-time in actual environments.

Howden Ventsim Design software is a 3D ventilation solution. Users create a 3D model of tunnels, shafts, and raises using existing 3D drawings. They can simulate and animate airflow and fan behavior in real-time and analyze mine ventilation within a visual environment.

Ventsim Control is a mine ventilation solution, including data analytics tools. Uses can change mine ventilation to fit working schedules and real-time operations. Fan speed is automatically reduced or increased or switched on and off according to shift changes or planned events such as blasting and position of vehicles and personnel.

Software requires sensors like Bently Nevada's Ranger Pro to gather information.

Bently Nevada, a Baker Hughes subsidiary, sells condition monitoring sensors and software. Its condition monitoring platform, called System 1, collects high resolution vibration, process, and control system data from a Bentley Nevada device, a Programmable Logic Controller, or from another historian. An alarm on any machine-mapped tag will trigger data capture from all other tags.

The strength of Bently Nevada’s platform is that it is centralized. Plant data is often siloed as it is collected concurrently from handheld devices, manufacturer-installed sensors and third-party sensors. Each monitoring tool collects small pockets of information. System 1 is meant to access all plant data and make plant-wide analyses.

Bently Nevada software can also visualize data collected by sensors. The HMI Builder visually represents an entire plant system and shows operational health.

The company launched a joint venture with Microsoft Azure and an AI company called C3.ai. called BakerHughesC3.ai. The jointly developed BHC3 Production Optimization was also recently released. This AI-based application allows well operators to view real-time production data, better project future production and optimize operations for improved oil and gas production rates.

APM is a suite of software and service solutions that connects disparate data sources and uses advanced analytics to turn data into actionable insights.

GE Digital’s Asset Performance Management (APM) software connects disparate data sources and uses analytics to turn data into actionable insights. APM works across all equipment, all OEMs, and all industries, across the plant, and across the fleet. GE says that software is fast advancing in the energy industry equipment sector, especially advanced analytics, machine learning, and digital twin software. ■

The benefits of a digitalized, software-driven world for turbomachinery include the capacity to handle large amounts of data. Now, engineering teams can run larger, more complex simulations using cloud services and pass data seamlessly between teams.

Software expands turbomachinery capabilities

 The good old days at the 2019 Turbomachinery & Pump Symposium.[/caption]

The Annual Turbomachinery & Pump Symposium is regarded by many as the premier turbomachinery event. Traditionally set in Houston, TX, the live event was cancelled due to Covid-19. Organizers at Texas A&M’s Turbomachinery Laboratory valiantly battled to provide a virtual version in December of 2020. However, there is nothing like the real thing.

A wealth of sessions made up for the lack of a buzzing exhibition floor. Topics covered included hydrogen compression, seals, gas turbine (GT) performance, combustion, additive manufacturing, turbomachinery in refineries, and operations & maintenance.

Rainer Kurz, Manager of Systems Analysis at Solar Turbines, walked attendees through the performance of the compressor, the combustor and the turbine section during a tutorial session. Also discussed were control concepts for single-shaft and two-shaft machines driving generators, compressors, and pumps.

GT performance characteristics depend on ambient and operating conditions. Consideration must be given to site elevation, ambient temperature, relative humidity, speed of driven equipment, fuel, and load conditions.

Kurz introduced data analysis methods and detailed the impact of degradation on component performance, engine performance, and approaches to mitigation.

His takeaways: Applications for industrial gas turbines will change but will be with us for a very long time. “With or without hydrogen, natural gas will play a key role in the transition towards a more sustainable energy future,” said Kurz.

As engineers seek to adjust turbomachinery to hydrogen service, challenges will inevitably materialize. One such challenge, hydrogen induced cracking (HIC), was the topic of another session.

Centrifugal compression is dependent on gas molecular weight. Aerodynamic head is developed by increasing the gas velocity to raise kinetic energy levels, then by converting the kinetic energy to potential energy through diffusion. The resulting impact is an increase in static gas pressure. The amount of kinetic energy imparted into the gas is a function of gas velocity and molar mass. To achieve high gas velocities, an increase in impeller rotational speed is required. This imparts higher stress on centrifugal impellers, which can exceed guidelines provided by American Petroleum Institute (API) Standard 617, eighth edition (2014).

To utilize the benefits of higher rotational speed, therefore, new strength limits for the application of materials in hydrogen gas compression are required. Svenja Haarmann, Head of Chemistry at Siemens Energy delivered a talk on the HIC resistance of common impeller alloys. She compared them, utilizing National Association of Corrosion Engineers (NACE) standard test method TM0177. The goal was to determine a test procedure and validate higher-strength materials suitable for hydrogen compression environments. Chemistry, microstructure, mechanical properties, and heat treatments were examined to explain the results observed and seek predictors for high-strength materials in hydrogen service.

“HIC can occur in highly stressed materials,” said Haarmann. “High rotational speed is required in hydrogen centrifugal compression to achieve a reasonable head rise per stage, leading to high impeller stresses.”

She noted that, per industry standards, the maximum yield strength for all materials used in hydrogen service is limited to 120 ksi. Test results indicate that this number is overly conservative. Testing reveled that some alloys could perform well at 145 ksi and another as high as 160 ksi. Such alloys, therefore, have high potential for hydrogen environments. Updating industry standards to allow higher impeller stress will allow smaller, faster running compressors in hydrogen service.

Many sessions at the conference were devoted to seals and especially dry gas seals (DGS). Pipeline sealing, for example, is challenging as you often don’t know what is coming down the pipeline. Therefore, operators are looking for increased reliability and better control of leakage or lost product, during normal opeation and catastrophic seal failures.

Jim Wasser, Global Director of Design Engineering and John Morton, Product Line Director, Advanced Wet Sealing Solutions, John Crane, said most operators use single seals of various kinds on crude duties. When they have to deal with NGLs, seal technology can vary greatly. In North America, for example, conditions can vary between -25°C to +30°C and viscosities from around 2 to in excess of 3,000 centistokes (cSt). Seal chamber pressures can be up to 1,200 psi.

Two years ago, John Crane introduced non-pusher secondary sealing technology to improve seal performance on crude services. That same technology has now been developed into a family of seals capable of handling non-crude liquid hydrocarbon applications.

“Non-pusher secondary sealing technology brings about no change in seal balance in high or low pressure applications, unlike seals utilizing a full convolution elastomer bellows,” said Wasser. “It can flex along the balance diameter and is capable of 0.8 mm shaft axial movement.”

He added that it is robust enough to handle high startup torque and shaft misalignment. No hard coating is required on the sleeve as there is no movement of the secondary sealing element.

Several discussion groups at the show took up seals. Stefan Cich, a Group Leader in the Machinery Section at Southwest Research Institute, led a discussion group on DGS systems. He took attendees through their history, starting in 1970 as a response to the need for a less complex and hazardous system than floating ring oil seals.

“Non-pusher secondary sealing technology brings about no change in seal balance in high or low pressure applications, unlike seals utilizing a full convolution elastomer bellows,” said Jim Wesser, Global Director of Design Engineering.

DGS are used as low-leakage shaft end seals for many centrifugal compressors and other turbomachines. Such sealing technologies help limit leakage. As governments and companies continue to limit carbon emissions, leakage

DGS configurations include single seals, tandem seals (sometimes with an intermediate labyrinth seal), said Cich. He also covered fundamentals, turbomachinery applications, and design considerations for reliability.

Seal testing can ensure design conditions are met. Test rigs can study off-design conditions such as transients or contaminant injection. In addition, he offered insight into failure modes specific to heat generation from

Combustion Components and Additive Manufacturing 

Additive manufacturing (AM or 3D printing) is particularly suitable for making small, complex parts and components, especially within the GT combustion system. Gianni Panfili, AM Manager and Kevin Sheehan, Head of Design for AM, at Siemens Energy, discussed how these methods are being used to improve the reliability and thermo-mechanical fatigue resistance of select parts by eliminating potential crack initiation points at braze locations. They touted benefits such as rapid prototyping, reduced part lead times, and lower repair and lifecycle costs.

AM is particularly suited for combustion system and hot gas path components, which are complex and function in harsh operating conditions. Combustion systems in gas turbines need to provide the necessary flow dynamics for efficient combustion and environmental control.

The speakers presented several use cases where AM methods were used to fabricate parts for GTs. AM burner heads were produced for a conventional dual-fuel injector on a 38 MW aeroderivative GT model. Siemens replaced the head portion of the burner with a single AM piece welded to the rest of the burner, simplifying the manufacturing and repair process.

In another example, AM was used to manufacture the central fuel injector of a dual-fuel, dry low emissions (DLE) variant for a 38 MW GT, commonly used in offshore applications. The component was manufactured as a single printed part, optimizing some features to enhance functionality, particularly the combustion noise signature at low power.

A group of experts from Elliott Group hosted a session on compressors, expanders, steam turbines, and GTs used in refinery applications. Speakers covered refinery processes, design conditions, and challenges.

Fluids pose aerodynamic and material challenges due to corrosive, flammable, and sometimes toxic elements. Therefore, refineries require a wide range of durable turbomachinery that must operate flexibly under harsh, fluid conditions. These requirements make the design, packaging, controls, application, and operation of turbomachines in refineries complex and challenging.

Speakers discussed operational and technical details of turbine and compression applications such as gas boost, refrigeration, hydrogen recycle, blow gas compression, coke gas compression, reformer recycle compression, steam turbine drivers, and GT drivers.

Siemens Energy provided another tutorial on aerodynamically induced forces acting on centrifugal compressors that can cause rotor vibration. There are several sources of non-synchronous forced vibration of centrifugal compressor rotors. Many of them are aerodynamic phenomena, created within the gas flow path of the compressor. Phenomena such as impeller stall, diffuser stall (with and without vanes), and flow instabilities caused by impeller to diffuser misalignment, are all characteristic flow disturbances that can cause forced vibration. However, the only indications of these phenomena may be found via rotor vibration signals. CFD analytical results and dynamic pressure transducer test data can be used to verify the presence of these phenomena.

Another discussion group zeroed in on operations and maintenance. Subjects discussed included LNG plant maintenance, continuing to maintain turbomachinery even if offline for an extended period, water washing, aging turbines, and condition monitoring.

During commissioning of a new eight-stage CO2 pipeline compressor, higher than expected seal vent flows were detected from carbon ring seals in the high pressure (HP) stages. The machine could not meet design performance.

Patrick Smith, Principal Engineering Associate at Air Products & Chemicals, laid out this case study. He described the design of the carbon ring seals, the history of the problem, the results of a root cause analysis, conclusions and corrective action taken.

The HP section of the eight stage, 4-pinion, integrally geared centrifugal compressor was running 11% short of capacity. It ran wet in the first five stages and dry in the others. The compressor was driven by a 13 MW (17,500 HP), 1,800 rpm motor. Pinion shaft seals were nitrogen-buffered carbon ring seals. The number of rings differed depending on pressure. While these kind of carbon rings can last many years, they operate with very tight clearance to control leakage.

The problems encountered applied to the stage 6 to 8 seals. In response, Air Products added a manual valve to the HP vent header to allow throttling and increasing back pressure.

“The root cause was found to be deformation of the seal support plates due to axial forces from differential pressure across the seal rings,” said Smith. “In response, we strengthened the seals by increasing the number of support ribs.”

From 11% below capacity prior to the outage, the new design reduced the HP section capacity to only 3% short of design capacity. The user reports no additional problems with the HP vent flow since this upgrade. ■

What we learned at the virtual Turbomachinery Symposium

The energy sector is in a constant state of change, perhaps more than ever. Stricter emissions requirements have come on the heels of shifting public support for environmental sustainability.

Efficiency has often been center stage in the turbomachinery sector, but as governments across the world promise carbon neutrality by mid-century, the end goal for OEMs has taken on a greater purpose. Gas turbines are now expected to burn more variations of fuel and be more flexible in their application, all while competing with wind, solar, and battery storage systems.

"With or without hydrogen, gas turbine technology continues to advance."

Natural gas generation will remain strong for decades

, according to reports from the International Energy Agency. But alternatives like 

 have garnered intense interest due to clean burning qualities and government support. Accordingly, most manufacturers offer turbines that can handle some level of natural gas-hydrogen blend. They are working to create future-proof turbines that can efficiently run on 100% hydrogen or a high hydrogen blend.

 The Ansaldo Energia AE94.3A F-Class outputs 495 MW in combined cycle and 992 MW in a 2+1 configuration.[/caption]

Ansaldo Energia is developing larger and more efficient H-class gas turbines for the combined cycle and peaking markets. Flexibility features include part-load operation, high turndown, and cycling operation to support the renewables, and the needs of large combined cycle plants.

In addition, the company is increasing the hydrogen combustion capability of all new engines and retrofits. The trick in developing blended fuel turbines is to reduce the negative side effects of hydrogen combustion such as derating, which drops power output and efficiency, increases emissions, and lowers operational flexibility. The company already has more than 200,000 operating hours in burning hydrogen-enriched fuels in its AE94.3A gas turbine.

Sequential combustion technology, such as that in Ansaldo Energia’s GT26 and GT36 turbine models, offers advantages for hydrogen combustion. The latest high-pressure tests at full engine conditions, demonstrated that the engine’s sequential combustion is suitable for hydrogen combustion.

Ansaldo Energia’s most popular gas turbines are the GT36 H-class and AE94.3A F-Class. The GT36 H-class outputs up to 538 MW and can use hydrogen up to 50% volume without derating. It is a good fit for combined cycle plants. The AE94.3A F-Class outputs 495 MW in combined cycle mode and 992 MW in a 2+1 configuration. It can burn up to 25% hydrogen by volume. Further improvements are under testing.

GE has a well-known gas turbine portfolio that includes H-class, F-class, B and E-class, and aeroderivative turbines. The HA and F-class turbines offer the greatest fuel flexibility and power.

The company’s ability to close transactions, particularly services parts & upgrades, has been impacted by constrained customer budgets and access to financing due to oil prices and economic slowdowns. GE said it anticipates the power market to continue to be impacted by overcapacity in the industry, increased price pressure from competition on servicing the installed base, and the uncertain timing of deal closures. The company has gained 32 orders so far in 2020. That compares with 52 for the first three quarters of 2019. The company remains the top gas turbine manufacturer; it is forecast to account for nearly 30% of units produced over the next decade.

GE’s 384 MW 7HA.02 combustion turbine, which can burn between 15-20% hydrogen by volume, is known for its ability to use various gas blends at high power and efficiency. The turbine is being used at the Long Ridge Energy Terminal, a 485 MW combined cycle power plant in Ohio, that will transition to run on hydrogen as soon as next year. The plant is the first purpose-built hydrogen plant in the U.S.

The company has also been developing a multi-tube combustion system known as the DLN 2.6e. Optimized for operation on natural gas, it can operate on blended hydrogen and natural gas, with up to 50% (by volume) hydrogen.

 Cross section of Opra OP16 turbine engine[/caption]

OPRA, a Dutch turbine OEM, has developed combustor technology to utilize up to 100% hydrogen in its gas turbines. Earlier this year, it ran its turbine successfully in a test using 100% hydrogen.

Its most popular model, the OP16, is an all-radial gas turbine, which provides robustness, reliability, efficiency, and low emissions. Its main markets are industrial, oil & gas and waste-to-energy applications.

The OP16 can operate on a wide range of gases, from ultra-low calorific gases (~5 MJ/kg) to high calorific gases including 100% H2 while fulfilling stringent emissions regulations. The turbine can also handle sour or contaminated gases often seen in oil & gas applications.

The OP16 comes in three variants: The OP16-3A, a diffusion combustor; the OP16-3B, a dry low NOx combustor; and the OP16-3C, a low-calorific fuel combustor.

 Kawasaki 1 MW class M1A -17 gas turbine.[/caption]

In the last decade, CO2 reduction has become a global trend. The Japanese government has set policy to expand the use of hydrogen to reduce CO2 emissions from its thermal power generation plants.

Kawasaki Heavy Industries came up with a hydrogen supply chain concept almost ten years ago and has been making company-wide efforts to build a hydrogen chain for producing, transporting, storing, and using hydrogen. The company is developing technologies that can handle a wide range of applications, from hydrogen mix with natural gas to 100% hydrogen combustion. These technologies are being developed for 1 MW gas turbines and will be gradually introduced to the market.

In Kobe, Japan, the company is conducting a hydrogen demonstration project. In 2018, it demonstrated that a 1 MW M1A-17 gas turbine could burn 100% hydrogen, utilizing the generated electricity and steam at a nearby large-scale event facility and hospital. This year, the demonstration is using an MMX combustor (Dry Low Emissions – DLE) instead of NOx reduction by water injection. The test operated at 100% hydrogen with DLE for the first time and achieved an efficiency improvement of 1 point from the wet (NOx) method.

“We are developing and demonstrating the technologies necessary to build a hydrogen supply chain in order to respond to the expansion of hydrogen utilization worldwide,” said Koji Tatsumi, Senior Manager of Gas Turbine Engineering Department for Kawasaki Heavy Industries.

“We are demonstrating in a pilot that we produce a large amount of low-cost hydrogen in resource-rich countries, transport it as liquefied hydrogen to other countries, and unload and store it.”

Kawasaki gas turbines are available in sizes from 1 MW up to 30 MW. The primary model is the 7 MW M7A gas turbine. It is suitable for paper manufacturers and chemical plants desiring in-house power and steam generation.

 Mitsubishi Power’s hydrogen gas turbine[/caption]

Mitsubishi Power offers gas turbines ranging from 30 MW to 560 MW. The company has developed turbines that can operate on a mixture of 30% hydrogen and 70% natural gas. They are now working toward one that runs on 100% hydrogen.

At the company’s T-Point 2, a complete combined cycle power plant operating in a 1x1 configuration (one gas turbine, one HRSG, and one steam turbine), turbine designs undergo long-term validation of at least 8,000 hours – equivalent to nearly one year of normal operation.

T-Point 2 aims to be the power plant of the future partly because it uses machine learning and artificial intelligence technologies that will be available in a digital product called Tomoni, a customizable suite of user-driven, digital power plant solutions. The company hopes for T-Point 2 to become the first autonomous power plant in the world.

Mitubishi Power’s most popular model is the J-Series Advanced Class JAC gas turbine – the industry’s largest. It operates at 64% efficiency and 99.6% reliability. The company has been focusing on improved output and fuel efficiency, along with hydrogen combustion and artificial intelligence. It is currently developing dry low NOx (DLN) combustion technology (multi-cluster combustor) for 100% hydrogen fueling. The technology is borrowed from MHI’s heavy-haul rocket launch division. These rockets run on 100% hydrogen.

“Although there is still a long path for natural gas and renewable power to continue to replace coal-fired power generation and decarbonize power grids around the world, we believe energy storage will be the next important development in decarbonizing power,” said Toshiyuki

“We plan to be leaders in natural gas power generation and in storage of renewable power. We offer both Lithium Ion battery storage and green hydrogen energy storage, and see these markets growing substantially already in 2020,” said Toshiyuki Hashi, Director, Executive Vice President, CEO, of Gas Power at Mitsubishi Power.

All of Siemens Energy’s large gas turbines, from the SGT5-2000E to SGT5/6-9000HL, are capable of running on up to 30% hydrogen by volume. Roadmaps are in place to develop the mid-term and long-term capability to higher hydrogen contents reaching 100%.

Similarly, the company has been enabling hydrogen operation in its medium and smaller gas turbines. The 24 MW SGT-600 runs on 60% hydrogen with near future targets of 75%, and the 50-62 MW SGT-800 runs on 50% hydrogen with an immediate target of 75% hydrogen.

All SGT turbine frames are used for power generation in either simple cycle, combined cycle or cogeneration applications. Those frames rated 40 MW or lower are also used for mechanical drive. Dry low NOx combustion systems are standard for all frames.

Recent developments at Siemens Energy include increased hydrogen co-firing capability of 85% in the near future depending on the market pull based on both rig testing at Siemens’ Clean Energy Center outside of Berlin, Germany and full engine testing in Finspang, Sweden. A road map is in place for 100% hydrogen, but 100% hydrogen capability needs joint R&D collaborations including industrial partners in order to realize full engine verifications. The company is also entering the commissioning phase of two SGT-600 DLE to run on hydrogen-rich process gas in Brazil.

 A group of Capstone C65 microturbines on a rooftop in Canada, powering an apartment building.[/caption]

Due to the limited supply of hydrogen, Capstone Turbines developed microturbines as a distributed generation energy source to be easily installed at the source of hydrogen generation, without the need for infrastructure.

The company has patented a hydrogen-fuel injector. And it’s been working with Argonne National Lab and UC Irvine to test current systems on hydrogen blends. Capstone sold its first hydrogen C65 earlier this year to Australia.

“At the moment, there is not a huge commercial market for hydrogen-fueled power generation, but we recognize the opportunity that this growing market could provide in the future,” said Don Ayers, Senior Director, Engineering and Quality, Capstone.

Capstone Turbine’s microturbines range from 30 kw to 1 MW. The larger unit can be deployed in arrays up to 10 MW. Capstone’s primary markets are energy efficiency, oil and gas, and renewable energy. Their microturbines are installed in combined heat and power (CHP) and combined cooling heat and power (CCHP), power-only, direct exhaust, and steam applications.

Capstone microturbines are often installed as the backbone of multiple microgrid installations. Many of its oil and gas projects are flare gas valorization applications using otherwise wasted gas as a power source. Its machines operate on a variety of fuels including natural gas, propane, butane, various sour gases, renewable fuels such as renewable natural gas, landfill gas, biogas or digester gas, kerosene, hydrogen, and diesel.

Capstone’s most popular model is the C65, though its C200/1000 series product has increased in volume since its launch in 2008. It is compact and can produce enough heat to provide hot water to a 100-room hotel while also providing about one third of its electrical requirements. ■

Gas turbine innovation, with or without hydrogen

A new range of small low flow, modular desiccant air dryers for critical air quality applications has been launched by SPX FLOW configured for the North American and LATAM markets. The Hankison HSHD Series Desiccant Air Dryers have been developed to protect moisture sensitive applications requiring low-pressure dew points.

With reduced footprint than previous designs, Hankison HSHD Series modular desiccant dryers provide high quality compressed air economically and efficiently. Moisture sensitive applications range from food processing and packaging to laboratories and pharmaceutical production.

The HSHD Series are pressure swing adsorption dryers and deliver pressure dew points to ISO 8573-1:2010 Air Quality Class 1 (-94°F/70°C) and Class 2 (-40°F/-40°C) with flow rates of 7 to 40 scfm (12 to 68 m3/h). Activated alumina, a highly porous material, efficiently adsorbs moisture from the processed air. The purge rate is kept to a minimum, effectively desorbing moisture from the desiccant bed, while reducing energy consumed, lowering operational costs.

HSHD dryers are comprised of two extruded aluminum columns equipped with desiccant cartridges. Air is passed through the on-line cartridge to remove the moisture, while the off-line cartridge is regenerating. After a pre-set time, based on the pressure dew point requirement, the airflow is redirected to the cartridge previously being regenerated. The desiccant cartridges are easy to service making routine maintenance simpler. The desiccant bed has been sized to prevent fluidization and desiccant aging, prolonging service life. In addition, a high-performance filtration, consisting of an oil removal pre-filter and particulate after-filter protect the dryer and downstream equipment for optimal performance.

Furthermore, with connectivity and automation becoming increasingly important, SPX FLOW has equipped the HSHD Series dryers with a controller that includes Modbus communication protocol. This enables the dryers to communicate seamlessly with other inplant devices, such as compressors and monitoring systems, as part of an Industry 4.0-ready solution. The controller is equipped with a 7” color touchscreen for optimized viewing and to facilitate navigation. Operators may also select pressure dew point performance for maximum application flexibility.

Constructed primarily of aluminum components, HSHD desiccant air dryers are shipped fully assembled and ready for installation. Multiple inlet and outlet options offer flexibility of installation and a heavy-duty muffler furnished inside the dryer cabinet makes for quiet operation. The units are delivered as standard with pre and post-filtration, base mount provisions for floor standing, but can be wall-mounted using an optional kit.

Hankison launches new range of modular desiccant dryers

GE Power saw sales drop 12% in the third quarter of 2020, while revenues increased 3%, driven by improved cost productivity and cuts in fixed costs, the company reported in its quarterly financial results. Revenues for the quarter reached $4.025 billion, up from $3.926 billion for the same period in 2019. Profit was also up by $300,000.

Both gas-based electricity generation and GE gas turbine utilization has remained stable, the company said. GE’s ability to close transactions, particularly services parts & upgrades, has been impacted by constrained customer budgets and access to financing due to oil prices and economic slowdown, especially in Gas Power. The company is catching up with suppliers on parts and projects that were delayed due to COVID-19 and expects to complete about 95% of all planned outages in the year.

“Although there may be market challenges in the near term, we believe gas will play a critical role in the energy transition and our view of the market has not materially changed, albeit timing on new orders is harder to forecast,” the company wrote in its quarterly report. “Power continues to right-size its business to better align with market demand and driving its businesses with an operational rigor and discipline that is focused on its customers’ lifecycle experience. In Gas Power, we continue to size the business for a 25-30 GW market, although acknowledge that the size any given year can vary. We remain focused on our underwriting discipline and risk management to ensure we are securing deals that meet our financial hurdles and we have a high confidence to deliver for our customers.”

GE Power said it anticipates the power market to continue to be impacted by overcapacity in the industry, increased price pressure from competition on servicing the installed base, and the uncertain timing of deal closures due to financing and the complexities of working in emerging markets. Market factors such as increasing energy efficiency and renewable energy penetration continue to impact long-term demand. The company had orders for 17 gas turbines in the quarter, making for 32 orders so far in 2020. That compares with 52 for the first three quarters of 2019.

GE Power revenue up for Q3, gas turbine utilization stable

 Mitsubishi Power’s first JAC gas turbine manufactured in America under way on the Savannah River, beginning its journey from Georgia to J-POWER USA’s 1,200 MW Jackson Generation project in Illinois.[/caption]

Mitsubishi Power shipped the first JAC gas turbine manufactured in America to J-POWER USA Development Co. Ltd. for its 1,200 MW Jackson Generation project in Elwood, Illinois.

The project supports the state’s commitment to renewable energy by providing efficient, flexible generation that complements additional wind and solar energy and reduces Illinois’ dependence on coal-fired generation. The M501JAC gas turbine in transit to Illinois is the first of two that Mitsubishi Power’s Savannah Machinery Works is manufacturing for the project and will be the first M501JAC installed in North America.

The Jackson Generation project’s combined-cycle power plant will be dispatched into the PJM regional transmission organization. It will help modernize and diversify Illinois’ power grid while generating enough electricity to power 1.2 million homes.

When the plant enters commercial service in 2022, it will be one of the world’s most fuel-efficient natural gas power plants, offering among the lowest carbon emissions of any combined-cycle plant. The project will produce 65 percent less carbon dioxide than a legacy coal-fired power plant. Because the plant is designed to enable more uptake of renewable power, the carbon reduction will be even greater when the plant is combined with renewables. The plant will be able to cycle quickly to meet fluctuating energy demands. It also will incorporate best available control technology to minimize emissions.

The JAC gas turbine’s fuel flexibility will enable the plant to use locally available fuel with higher ethane content, significantly improving project economics. The fuel flexibility combined with high efficiency will ultimately reduce electricity cost for consumers.

Introduced nearly a decade ago, the J-Series gas turbines, which are Mitsubishi Power’s largest, deliver a combination of 99.6 percent reliability and greater than 64 percent efficiency. The fleet has logged more than 1 million operating hours globally.

The original steam-cooled M501J design was upgraded with an enhanced air-cooled configuration in 2015. Since then, the JAC has logged more than 20,000 operating hours and 1,100 starts and has been verified at Mitsubishi Power’s grid-connected T-Point 2 facility in Japan. Mitsubishi Power’s rigorous verification process ensures high reliability both during start-up and once the turbine enters commercial service.

Like its twin, the second turbine for J-POWER USA’s Jackson Generation plant is being manufactured at Mitsubishi Power’s Savannah Machinery Works. The world-class facility opened in 2010 and today manufactures key gas turbine parts, provides complete steam turbine services, and manufactures advanced fuel-efficient gas turbines. The facility employs more than 180 people.

Mitsubishi Power ships first American-manufactured JAC turbine to Illinois

Until 2016, coal’s fall from grace and the growing share of renewables on the grid had caused the ST market to contract. But growth and stability have returned. Demand is returning for small- and mid-sized combined cycle power plants (CCPP), combined heat and power (CHP), petrochemicals, biomass and concentrated solar power (CSP) solutions. All include an ST element.

With sales recovering, globalization is another trend noted by ST OEMs. Most have established joint ventures with customers and suppliers across the world, which helps turbine companies boost market share, decrease costs, and gain access to new business.

Innovation in STs may not be fast paced when compared to the developmental progress made in the gas turbine field. Nevertheless, OEMs such as Mitsubishi Compressor, Doosan Škoda Power, Siemens Energy, Fincantieri, Triveni Turbine, Baker Hughes, Howden, Ansaldo Energia, Elliott, GE Steam Power and MAN Energy Solutions, among others, have made strides in performance optimization, reduction of carbon emissions, improved efficiency, start-up speed/flexibility and in raising steam parameters.

Turbomachinery International Magazine interviewed several of these OEMs to find out the latest trends dominating the steam turbine sector. They offer a diverse set of market insights.

A charge gas compressor drive steam turbine from MCO for a 1.8 MMTPA ethylene plant.

Mitsubishi Heavy Industries Compressor (MCO) said its steam turbines are used predominantly in the petrochemical market. Particularly for ethylene plants of 2.0 million tons per annum (MMTPA) and above, the company has developed 20” longer blades to allow a wider variability in operating range. It has also developed STs designed for capacities of 3.0 MMTPA. As a result, its machines can now provide up to 140 MW to drive the cracked gas compressors (CGC) that are central to ethylene plant operations.

Overall, MCO offers API 612-compliant ST packages ranging from 3 MW to 140 MW. In conjunction with other MHI group companies, the company also serves the power generation market.

In recent years, MCO has focused on enhancing the operational efficiencies, reliability and maintainability of its ST packages, according to Tomohiro Mori, Application Engineer, at MCO. They are capable of automatic operation. The sequence from start-up to shut down is controlled by the programmable logic controller (PLC).

One of the company’s most popular models is the 9EH. “9” indicates the frame size (basic diameter of the control stage is approx. 900 mm). “EH” refers to the condensing turbine with an extraction pressure that controls the turbine under high-temperature and high-pressure conditions. It is typically used with a cracked gas compressor in ethylene plants.

In addition, the 9EH model addresses higher plant capacity. It can handle steam at very high temperatures (566°C/1050°F) and pressures (150barg/2133psig). It also provides improvements in energy consumption: the extraction steam from a cracker gas compressor steam turbine is used as the inlet steam for the refrigerant compressor ST.

Wherever heat is available and there is a demand for power, you are likely to find one of turbomachinery’s oldest and world-changing inventions – the industrial steam turbine (ST). The technology has come a long way since its first modern manifestation in 1884, persisting through every market boom and bust.