This is a guest post by Dan Zegart of the Climate Investigations Center
With builder Southern Company still promising that the Kemper power plant will go online soon, a group of key engineers and managers who work on the plant’s so-far-inoperable gasifier has left the company.
Earlier this month, Southern Company posted a cluster of want ads on its web site for a “gasification owner,” a “refinery technician-mechanic,” a “refinery technician-entry level,” and a “gasification technician.”
Those four positions are located at the gasification island, home to the patented TRIG technology developed by Southern Company and Kellogg Brown & Root that is supposed to turn lignite coal from an adjacent mine into a cleaner burning syngas to produce electricity. The project’s twin gasifiers, however, have been troubled by frequent shutdowns and lengthy repairs.
The plant’s operations manager, one of the most senior positions at the facility, tasked with day-to-day oversight of the entire power plant and its roughly 100 permanent employees, was also for hire until the posting was pulled from the Southern Company website over the weekend.
“The Operations Manager will be responsible for providing leadership for the Kemper County Generating Facility,” according to the job summary, and must foster “reliable and efficient plant operations of the lignite processing, syngas production, gas cleanup, chemicals production and power generation units.”
If the history of the first-of-its-kind plant so far is any guide, it appears that relentless pressure by Southern Company to meet unrealistic construction and operations milestones paired with the failure of the coal gasification equipment to work for more than a few days at a time, and then at only a fraction of rated capacity, has led several demoralized engineers to leave what they see as a sinking ship.
The Mississippi Power Company, the Southern Company subsidiary that operates the plant, notified investors today that the plant will not go online as promised in mid-March but offered no new date, saying that will be provided in a company status update in early April. This time MPC blamed “certain tube leaks in one of the syngas coolers for gasifier “A” which caused “an outage on gasifier “A” to perform necessary corrective actions.”
A New York Times expose last July described what were apparently deliberately faked company estimates of when the plant could begin producing electricity – its commercial operating date, or COD – and correspondingly false estimates of how much Kemper would cost to build, first estimated at $1.2 billion and now at $7.1 billion. These allegations also figure into an SEC investigation and a series of lawsuits by investors, customers and at least one company involved with the project.
Southern Company chief executive officer Tom Fanning has called the New York Times’ allegations “garbage” and claims Kemper will yet perform as promised.
But Fanning also admitted last month that a company “Economic Viability Analysis” found that the plant can’t profitably generate electricity from coal and is only economical operating on cheap natural gas. A few weeks later, the credit rating of Southern’s Mississippi Power Company subsidiary, owner of the plant, slid to junk status.
With help from engineers familiar with the plant’s design, the Climate Investigations Center looked closely at a series of technical reports by an independent watchdog that seem to indicate that the plant and the technology it represents are in deep trouble and may never work properly.
In Meridian, the city nearest Kemper, the scuttlebutt is that a number of Kemper engineers and managers are looking for a way out of a project that increasingly seems ill-fated.
Low morale at Kemper Nothing New.
The New York Times piece featured audio of conversations recorded between plant engineers and managers commiserating about sloppy construction, non-existent quality control and inadequate safety measures as workers raced to meet deadlines.
In one recording, then-Operations Manager Tim Adams complained to a colleague that inspections that were to verify that the final construction of the plant’s equipment actually matched the original design were so inadequate that “we threw a damn fit over it.”
“They were just trying to hit milestones,” said Adams in the August 2014 recording. “They weren’t focused on all the other stuff. That wasn’t their marching orders.”
Seven months after that conversation, Adams quit and joined a petrochemical refiner in Alabama. Two years later, the position has apparently turned over again.
Aside from the operations manager, the gasification technician, according to the web site, is charged with operating and maintaining “the gasification power train, syngas clean-up, chemical product production, [and] Combined Cycle” and is to “monitor and troubleshoot the gasification processes and respond to emergency situations.”
(The combined cycle island, in contrast to the gasifier island, is where the syngas would be burned in a pair of combustion turbines to generate electricity. That part of the plant has been producing electricity since the summer of 2014, but on natural gas.)
The gasification owner is “directly responsible for providing tactical and strategic planning…[for]…all unit operations from lignite processing, syngas production, gas cleanup, chemicals production, and power generation,” according to Southern.
The gasification owner and gasification technician jobs are management. The refinery technician – mechanic position is a “multi-craft” union job that involves maintaining the plant’s equipment, and that requires “in-depth knowledge and understanding to operate all traditional… Integrated Gasification Combined Cycle or Petro/Chemical plant equipment.”
The refinery technician – entry level, also union, “performs plant operations, maintenance and instrumentation duties.”
Repeated calls over a period of days to Mississippi Power seeking comment about the job postings and other issues raised in this article were not returned.
A Coal-Fired Petroleum Plant
The word “refinery” appears in the Kemper job descriptions because the plant’s technology comes from the petrochemical industry and therefore most of Kemper’s key gasifier personnel have petrochemical – rather than coal power plant – backgrounds.
The TRIG gasifier is based on a fluid catalytic cracking process used in refineries to produce gasoline and other petrochemical products from oil, a process KBR, an oil industry heavyweight, was already expert in.
The problem is that the process was originally designed to work with fluids – not coal, and especially not lignite, a dirt-like, sticky coal that comes out of the ground at the adjacent Liberty mine at close to 50 percent moisture by weight, and is still at least 20% after drying. Lignite is more polluting and yields less energy than any other type of coal.
This is what the Kemper plant and TRIG are supposed to gasify, and TRIG does it by spraying granularized coal into a reactor at 1740 degrees Fahrenheit at 650 pounds per square inch of pressure, turning the coal into a gas.
For some reason, however, Kemper’s reactor is having a recurrent problem that’s prevented the gasifiers from running properly and still isn’t solved, according to reports by AECOM, an engineering and construction management firm that is the Independent Monitor for Kemper, acting as a watchdog on behalf of the Mississippi Public Service Commission.
The Independent Monitor’s monthly progress reports include punch-lists of problems that are preventing the plant from producing electricity from syngas instead of natural gas.
To do that would mean having gasifiers that can reliably produce syngas. But in identical language in every report since August, the IM calls attention to a recurrent problem in Gasifier B that required a shutdown and lengthy repair, a problem that had earlier closed Gasifier A.
A Pressurization Problem
The coal that is sprayed into the reactor is cold compared to the inside of the reactor, and a small portion of the coal is burned to offset the heat loss. But because the gasifier has almost zero oxygen, the vast majority of the coal “gasifies”, turning into syngas and ash.
If coal is fed at a high enough rate, the volume of syngas it produces boosts the pressure inside the gasifier to a level necessary for proper “fluidization” of the solids (ash) in the gasifier. This fluidization is what makes the design similar to a KBR fluid catalytic cracker used in an oil refinery.
However, if coal is not fed into the gasifier fast enough, the pressure can’t build to proper levels and fluidization can be lost, resulting in high temperatures – “temperature excursions” – and the formation of a sticky molten slag that adheres to the walls of the reactor like fatty deposits on an artery and hardens into stoney “ash clinkers” that can eventually grow large and fall to the bottom of the gasifier, clogging it up.
Once the flow inside the gasifier becomes unpredictable, large volumes of accumulated air mix with injected coal, causing the temperature spikes. Uneven fluidization means the gasifier operator has a hard time controlling the air mixing with the coal, leading to surges and an unstable process. The end result is that the gasifier has to be shut down and the ash and clinkers removed.
Repairs have been going on to the reactor vessel in one or another of the two gasifiers, according to the IM reports, virtually all year.
The January IM 2017 report, like five earlier ones, calls for determining the “root cause” of these “temperature excursions,” and even questions “the long-term viability of the modified refractory system design…in both gasifiers.”
During Southern Company’s most recent earnings call, on February 22, a financial analyst asked CEO Fanning whether it was true that “this issue about removing ash deposits has kind of plagued, maybe I’m inaccurate, but have plagued both gasifiers.”
“How does that get resolved?” asked the analyst.
Fanning said the problems had to do with “ash that was melted due to some temperature excursions as we brought the plants into and out of service. We think we’ve solved all of those problems.”
Fanning said the most recent ash situation, in Gasifier B, seemed also to be because “we started and stopped it about 7 or 8 times,” and “what we have seen is, when you turn the plant on and off, the fluidization inside the circulating fluidized bed boiler stops” and “some of the ash just started sticking to each other.”
“So they’re going to take the plant out of service, get it out, start it up, and they think it’ll run fine,” he concluded.
“That’s the early problem and they’ve solved it,” he added later.
Not Everyone is So Sure
Others seem to believe the root cause is probably the coal feed system for Kemper. It is called the PDAC, for Pressure Decoupled Advanced Coal feed. Like several other plant systems, PDAC is first-of-its-kind, and it has so far not been able to pump in coal at the designed rate.
Evidence for this being the cause of the ash problem comes from the very first of the “Key Technical Milestones Not Yet Achieved as of 31 JAN 2017” in the Independent Monitor reports:
Achieve and reliably sustain full design coal feed rate (~400 kpph) to each Gasifier for a to-be-determined minimum period of time while continuing to produce on-spec syngas, CO2, ammonia and WSA products.
In fact, the coal feed system at Kemper has long been a trouble-spot, according to the IM reports, which have noted persistent clogging of various lignite handling systems. The reason it’s unreliable may be Southern’s very limited experience with PDAC.
The entirety of Southern Company’s development, testing and modeling of the PDAC system took place at Southern’s “demo scale” TRIG plant in Wilsonville, Alabama, a 7-megawatt power plant. The next stop was Kemper itself – a full-scale commercial facility of 582 MW, representing an 83-fold scale-up from demonstration phase to operating conditions. The impossibility of reliably scaling up any technology by such a large factor in one leap is a basic engineering principle.
Randall Hodges, part of the IM team at AECOM, declined to comment on the ash clinker issue, and referred all questions to Mississippi Public Service Commission counsel Shawn Shurden. Shurden also declined to go on the record.
“We’re under obligation of due process and can’t make any statements that appear to prejudge issues before the PSC,” Shurden said..
Brett Wingo, the former manager of the gasification island who blew the whistle on Kemper’s schedule and safety irregularities for the New York Times story, made a series of predictions in the summer and fall of 2016 about systems that would probably prove troublesome and might fail. PDAC was at the top of the list.
“They’re only just now getting to the real first-of-its-kind systems,” said Wingo in September. “The whole coal handling process is really totally untested.”
At that time, Wingo had worked out probabilities for when Kemper might go on-line based on his knowledge of the plant, plus information from the IM reports. All dates are from 2017.
End of February <20%
End of March approx. 30%
End of April approx. 40%
End of May approx. 50%
End of June approx. 60%
End of July approx. 70%
End of August approx. 80%
September or later >90%
Wingo’s accompanying notes suggest that 70 percent probability “is the beginning of what it is reasonable to expect as a date.”
That would put COD for Kemper off until at least July 2017. At the time he calculated those probabilities, in August 2016, the company was promising the plant would be operating at the end of October. Since then Southern has made five other claims about when Kemper would be ready.
“The challenge is for them to get all these untested systems to work – and to work together,” Wingo said. “If that doesn’t go well, you’re looking at 2018 sometime. At which point you’d have to ask if it’s ever going to work.”
Image credit: Kemper plant twin towers of gasifiers A and B. Picture taken while the plant was still under construction. Climate Investigations Center.