The INEOS Bio cellulosic ethanol plant in Vero Beach, Florida officially opened last year but has been reporting only spotty production of ethanol in the EPA’s EMTS transaction system for RINs.
Now, it has become clear why.
In a report filed by the State of Florida in recent months and obtained by The Digest, it was disclosed that “although the [INEOS Bio New Planet Energy] facility in Vero Beach, Florida is officially operating, very little fermentation or production of ethanol from the production fermentor has occurred, primarily because of the sensitivity of the bio-organisms in the fermentation process to high levels of [hydrogen cyanide] in the syngas.”
As a result, “installation of a HCN scrubber is essential for the fermentation process to be successful.”
According to INEOS Bio, the company remains highly committed to the project and sees the emergence of the problem with high HCN levels as the kind of challenge under at-scale operating conditions that exemplifies first-of-kind technology and that companies like INEOS have the team, technologies, and time to address.
Now, what is hydrogen cyanide and how deadly to organisms is it?
Better known as prussic acid, it was used as a killing agent in gas chambers on condemned prisoners; also used in the First World War by the US and Italy, and featured infamously in mass concentration camp killings in the Second World War under the brand name Zyklon B.
How much HCN?
According to Florida, at the INEOS plant, “the gasification of vegetative matter produces low levels of hydrogen cyanide (HCN) in the syngas of between 15 and 200 parts per million (ppm) depending on the operating conditions in the gasifier. In general, a higher gasifier temperature is required to achieve a lower HCN concentration. However, operating the gasifier at a very high temperature may lead to equipment unreliability, poor availability and high maintenance costs.”
The effect on the microorganism?
Florida reports: “The HCN in the syngas is toxic to the bio-organisms in the fermentation process and INPB has determined through pilot scale testing that HCN at a level of 15 ppm is too high for the bio-organisms in the fermentation process to survive. It has been determined that the maximum HCN concentration for bio-organisms survival is less than 10 ppm with levels of less than 1 ppm of HCN required for the fermentation bio-organisms to survive and to reliably meet the project design targets.”
Florida discloses, in its report, that the owners are “seeking authorization to construct and operate a wet scrubber to remove the HCN from the syngas after the gasification process at the INEOS Bio facility. This additional cleanup system will reduce the HCN concentration in the syngas to a level that is not harmful to the bio-organisms used in the fermentation process.”
Details of the additions at Vero Beach
The proposed fix includes a total of three new towers at the Vero Beach site. “This purpose of Tower 1 is to scrub HCN from syngas. The purpose of Tower 2 is to scrub HCN from the scrubbing water used in Tower 1 and the purpose of Tower 3 is to remove HCN from the air used in Tower 2 before releasing it into the atmosphere. Tower 3 employs a recirculating caustic/hypochlorite system to absorb the HCN from the air and convert it to thiocyanate.”
The HCN scrubbing system is designed to reduce the HCN concentration in the syngas to less than 5 ppm at the full gasification rate.
Status of the application
As of June, the state of Florida agreed that the “installation of a scrubber to remove HCN from the syngas will not results in an increase in emissions of any regulated PSD [Prevention of Significant Deterioration of Air Quality] pollution. With regard to the HAP [Hazardous Air Pollution] emission increase, the Department also concurs that due to the scrubbing of the syngas to remove HCN some emissions of this HAP will occur to the atmosphere. Consequently the Department will require an initial stack test on Tower 3 (Air HCN Scrubber) to verify the HCN emission rate of 3.8 TPY (0.87 pounds per hour).
Accordingly, the state has distributed a written “intent to Issue Air Permit” notice. The 14-Day comment period expired by the end of June. A draft final air permit has been issued by Florida.
Status of the fix
According to the project team, “INPB has implemented a pilot project at the Fayetteville, Arkansas, facility to test the sensitivity of the fermentation process to HCN concentration. The pilot project involved installation of HCN scrubbing and water regeneration unit to prove that the concept of HCN removal and regeneration can be successful at full scale.
The Fayetteville, Arkansas, system proved that fermentation is operable on mulch syngas after removal of HCN and provided design data for the proposed HCN removal and control system at the Vero Beach facility. The Vero Beach system requires a third column to remove the HCN from the air used to regenerate the recirculated scrubber water.
According to INEOS Bio management, the scrubber technology will be installed and commissioned by October and the plant should be resuming normal operations by the end of the year.
What we don’t yet know
First — although a formality at this stage, the State of Florida has not issued the amended air permit and construction, therefore, awaits that action.
Second, we don’t know precisely how long it will take to install, test and commission the new units — and return thereby, it is hoped, to nameplate production.
The Digest’s take
We’ve seen this from time to time in the sector. Unanticipated problems with a new feedstock causes the microorganism to struggle under industrial conditions. In this case — “vegetative matter” causing the trouble, as opposed to the yard waste, land clearing debris and untreated wood that the plant is permitted for, and the municipal solid waste that it is testing.
Back in August 2013, INEOS Bio COO Mark Niederschulte warned:
““With any plant, you turn it on, then start pushing it find out the bottlenecks. In this phase, we’ve got some not very expensive equipment to install – soon – probably September. Then we’ll see how those modifications lead us to another bottleneck, or it could be that that’s it. But we’re starting to see increased production, from better feedstock handling and processing, and improved overall operation. Until those mechanical changes are complete we’ll continue to see some constraints.”
The plant was mechanically completed in the first half of 2012 — and critics had became vocal about “shortcomings in the core technology” as early as last summer, when the plant did not complete its commissioning period more quickly.
In this case, there was a trade-off – operating the gasifier at higher temperatures would have solved the cyanide problem, but created other maintenance and reliability issues.
Bottom line: there’s good reason to suspect that the INEOS Bio facility will not be adding large batches of RINs into the system until much later in the year, or even 2015.
The complete data.
The complete Florida report can be downloaded here.
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