Welcome everyone back to LNG Academy Episode 3. Before we jump in, I’d like to acknowledge a few things.
First, the mission of LNG Academy is to spread LNG Education around the world. We aim to be as factual and non-biased as possible and focus our discussion on technical issues, with the hope that some of this knowledge will be beneficial to this great industry that we are proud to be part of and contribute to.
The opinions expressed in this podcast are solely based on those of the hosts. That is a perfect Segway to re-introduce my co-host, Mehdy Touil, LNG operations specialist. Mehdy, I’d like to express to you and our audience that I truly value you as a friend and colleague, and your presence on LinkedIn has truly inspired me. So merci, Mon Cher MEC
Lastly, I’d like to thank the sponsor of this podcast, Capstone Industrial Training Solutions, who has recently joined the Solaris group of companies. Capstone are leaders in the LNG and industrial training space, and Solaris leaders in engineering, project delivery and clean technology. For more information on Capstone and Solaris, please visit capstoneits.com and Solaris-mci.com.
Now let’s jump into our topic today, which is Cameron LNG Train 4.
In the last few weeks, we have seen a lot of activity on the US LNG scene: the FID approval for Sempra’s Port Arthur LNG Phase 1, FID for Venture Global’s Plaquemines LNG Phase 2, Freeport restart,… Basically, US LNG is trending. Baker Hughes won a large order from Bechtel to supply its Frame 7 gas turbines and refrigeration compressors for the first two trains at Port Arthur LNG. Congrats to Baker Hughes!
Meanwhile, Sempra is also focusing on Cameron LNG T4. What do we know about the project?
Let’s go back in time. In 2015, Cameron LNG filed with the US regulator, FERC, for the expansion of its existing 3-train facility with two additional trains, train four and train five plus one additional storage tank. In 2018, Sempra signed a memorandum with Total to cooperate on US LNG projects and the potential sale of 9 MTPA from the Cameron LNG Phase 2 project. In 2019, Sempra signed another memorandum, this time with Japanese Mitsui for the offtake of one-third of the planned capacity from Phase 2.
In August 2020, when Cameron LNG’s phase 1 last train, Train 3, entered commercial operations, Sempra announced that it could not give any assurance on the completion of its other LNG projects, including T4 and Costa Azul in Mexico. Remember, it was right at the start of the pandemic.
In June 2021, Sempra announced that instead of going with 2 trains of 5.0 million tons each, it was decided to cancel T5 and focus on scaling up the capacity of T4 to 6.75 million tons. The additional 160,000 cubic meter storage tank was also canceled.
Most recently, during its last earnings call, Sempra revealed that the front-end engineering & design process – the FEED – with Bechtel would be completed in the summer of this year. No indication was given on a potential Final Investment Decision in 2023.
Oh, very interesting looks like Sempra has been very busy.
What was the initial design for T4 and T5?
Initially, the proposed trains would have replicated the design of T1, 2, and 3. That is Air Products Propane precooled mixed refrigerant process, C3MR, with 2 Frame 7 EA gas turbines: one for the propane and HP MR compressors, and one for the LP and MP MR compressors. This is similar to other trains in the 4 to 5 million tons capacity range like the Qatargas South T3 to T5, Damietta LNG, Peru LNG, or the new trains at Arzew and Skikda in Algeria.
Alright, well we understand there is a design change for this new configuration. What is this design change? Can you expand on that a little bit?
The main design change was obviously the introduction of electric drive (or “E-Drive”) motors to replace the Frame 7 Gas Turbine drives for the refrigeration compressors, which are the main power consumers in LNG trains. The very first electric liquefaction facility was Equinor’s Hammerfest LNG in Norway, which uses Linde’s multi-fluid cascade process or MFC, and Siemens 65 MW and 32 MW variable speed drives for the refrigeration compressors. Power for the plant is generated by 05 LM6000 aero-derivative gas turbines. The next facility that we covered in the LNG academy episode 1 is Freeport LNG with its 690 MW sourced from the state of Texas grid. There are other projects down the road, most of them in Canada, like Woodfibre LNG, Cedar LNG, Ksi Lisims LNG, and LNG Canada Phase 2, and most recently Papua LNG developed by Total.
For Cameron LNG T4, the general project description mentions that the intent of the design modification is to reduce the overall scope 1 emissions, the direct emissions, from the project by eliminating the Frame 7 gas turbines and sourcing 300 MW of power externally. The output of the Frame 7 turbine at ISO conditions is 87 MW + 24 MW coming from the helper motor.
T4 will have a feed booster compressor to increase the inlet pressure to 68 bars, compared to 46 bars for T1, 2, and 3.
Also, the drier pre-cooler, which is a HH pressure propane chiller, will be provided with a separate propane loop including its own compressor driven by an electric motor. This is to allow the main propane system to be fully allocated to the liquefaction unit and scale up the capacity to 6.75 MTPA.
What is the new compression configuration Mehdy?
To maintain a proven size range, there is a restriction on the size of the electric motor drives to 75 MW. This means that instead of two gas turbine-driven compressor strings, the project will use three electric motor-driven compressor strings. The first string will be for the propane compressor casing, the second for the low-pressure mixed refrigerant compressor, and the third for the medium- and high-pressure MR compressors. Despite the change in drive, the liquefaction system’s process flow path remains the same as the original gas turbine design.
Ok and what are the other design changes?
By eliminating the gas turbines, you reduce considerably the plant scope-1 emissions, and you also eliminate the need for high-pressure fuel gas piping and vessels. But you also lose the waste heat recovery units that are included in the exhaust stack of the turbines. Most LNG trains use this lost energy to provide heating for the regeneration of the driers and other process users, mainly reboilers. In the case of Cameron LNG T4, gas-fired Hot Oil Heaters have been added to the system to provide this process heating. The heaters utilize low-pressure fuel gas to heat the thermal fluid which is circulated to the process users across the train.
Also, without the exhaust of the turbines, you have to think about a backup for dumping the acid gas stream from the acid gas removal unit in case the thermal oxidizer, which is an incinerator, is out of service or under maintenance. The project will include a low-pressure ground flare to enable the combustion of the acid gas stream hydrocarbons. We used to call it the sour flare in Qatargas because of the high H2S content.
It’s real interesting how a fundamental design change can have so many ancillary effects. What about the CCS component?
Cameron LNG is proposing a pre-investment tie-in on the acid gas inlet stream of the oxidizer on Train 4. In May last year, Sempra and its equity partners Total, Mitsubishi, and Mitsui signed an agreement for the development of the Hackberry Carbon Sequestration, the HCS project. The CO2 would be captured from Cameron LNG phase 1 and phase 2 and transported by pipeline to a compression facility. It will then be permanently stored in a saline aquifer using an injection well located approximately 8,000 feet under the surface of the earth with a capacity of up to two million tons of CO2 per year. However, FID for this scheme has not been reached yet.
Real interesting that we have seen so many of the carbon capture plants connected almost in tandem with LNG trains. Very interesting.
We’ve heard that several liquefaction plants in the US are having difficulties liquifying lean gas, would that be an issue for Cameron LNG T4 as well?
Not only in the US but in Australia and East Africa as well. Feed gas for Cameron LNG is supplied from the Cameron interstate pipeline, which is connected to 5 five major interstate pipelines linked to main markets in the US Midwest, Northeast, and Southeast. To meet pipeline specifications, gas producers tend to remove ethane and heavier components. It means that the methane-rich feed gas entering the liquefaction facility is low in C3, C4, and C5 but high in C6+ and contaminants like benzene. This is problematic as those will freeze in the cryogenic section, but you don’t have enough LPG to produce reflux and keep those contaminants at acceptable levels. You may need to reduce production or even shut down the train for defrosting in the most severe cases.
You need also to consider your refrigerant makeup requirements. Cameron LNG predicted a wide variation in the NGL recovery rates, which is why the Phase 1 design introduced small and large fractionation units in a parallel arrangement, and use ethylene instead of ethane for MR make-up. Another method is to inject LPG to support better separation and alter the physical properties of the contaminants, a method already in use by some US plants, including Cameron LNG to minimize the carry-over of those contaminants.
For the design of a C3MR train, you have 2 options: a scrub column integrated with the MCHE- all static equipment -, or a standalone turboexpander NGL recovery unit. The scrub column operates at the same pressure as the MCHE, which is not optimum for lean operations as liquefaction is more efficient at high pressure. For Cameron LNG T4, the NGL unit will use the open-art GSP process developed by Ortloff in the 70s with dual reflux for enhanced NGL recovery, with the addition of a compressor to increase the pressure at the inlet of the MCHE to 80 bars as compared to 70 bars for the Phase 1 trains.
Sorry, you said open art. I don’t think I understood that one.
Similar to open source, open art in process engineering means available to the public, in opposite to licensed technologies.
I would like to mention the economics of operating lean gas LNG facilities which may come at a high cost. You don’t have the benefits derived from NGLs and Condensate which are high-value byproducts. Below some gas price levels, your facility can become uneconomic. This is why efficiency is critical for lean gas liquefaction, and the high pressure allows for considerable savings in terms of refrigeration duty for larger capacities.
If Sempra and its partners decide to move forward with the project, Cameron LNG T4 will be the industry’s largest liquefaction train based on an all-electric configuration.
Amen to that. Well, we wish Sempra and its partners the best of luck in their Train 4 development.
Thank you Mehdy. Thank you audience and we will catch you on the next episode.