Dual Fuel--Colocating Ethanol, Biodiesel

Biodiesel tanks are popping up in the tank farms at some ethanol plants these days. This article first appeared in the May issue of EPM.
By Keith Loria | April 13, 2016

During the past decade, there has been a great deal of innovation and thought put into the synergies between ethanol and biodiesel production, as plants share infrastructure and process essentials. Colocating biodiesel production at an ethanol plant also could be considered a good hedge for an ethanol plant, adding value to the corn oil produced and supplying a different segment of the fuel market.

For ethanol producers, it means greater diversification and better fulfillment of the renewable fuel standard’s (RFS) vision, bringing in revenue from biodiesel sales and D4 RIN generation (the renewable identification numbers needed by obligated parties to demonstrate RFS compliance). Always looking for new opportunities, the ethanol industry is keeping an eye on the first adopters. In this issue, Ethanol Producer Magazine checks in on several projects.

WB Services recently completed a 2 MMgy biodiesel plant at Adkins Energy LLC in Lena, Illinois. “The biodiesel plant is adjacent to Adkins’ ethanol plant and the two are integrated through several stretches of piping,” says Ray Baker, general manager at Adkins. “It is sized for a capacity of 2 MMgy per year, which is closely matched to our corn oil output and local market demand for biodiesel.”

Adkins has been producing biodiesel for about one year, he says, running both a traditional chemical and new enzymatic process.

“Our operations team has really enjoyed working with the enzyme process since it has similarities to the ethanol production process,” Baker says. “We’ve had several start up challenges throughout the year, but have worked our way through the majority of them. Our staff has done an excellent job transitioning to biodiesel production and they have been consistently improving output, yield and efficiencies throughout this first year.”

 Issues solved during the first year included optimizing methanol recovery and its transfer to ethanol operations and meeting guaranteed performance standards with the chemical process. Several combinations of equipment and procedural changes were made to improve the traditional process.
There are several advantages to colocation, Baker says. “All of our biodiesel coproduct and wash water streams are sent to the ethanol plant for processing. Through our ethanol operations, we are able to push our glycerin out to the distillers grains, our unused methanol is sent through distillation with our ethanol, and our remaining wash water is reused in the ethanol process. Our biodiesel coproducts are able to provide strong returns through existing ethanol product lines without creating the need for new market development.”

WB Services installed both a traditional acid esterification and base transesterification system and an enzymatic process—a newer technology in the biodiesel space. Having the ability to choose between two processes was a key reason Adkins chose the technologies.

 “There are several reasons, but the main reason is to allow for operational flexibility based on market and cost-of-production economics,” Baker says. “Using the enzymatic process eliminates the use and potential employee exposure to sulfuric acid, while also extending the life of the process equipment.”

WB Services has two other projects under construction, both 3 MMgy renewable diesel plants at Kansas ethanol plants. East Kansas Agri-Energy LLC was expected to begin operations early this year and the project at Prairie Horizon Agri-Energy LLC is expected to wrap up in the second quarter.

Super Jatrodiesel
Like WB Services, Ohio-based Jatrodiesel is offering two technologies for biodiesel production colocated with ethanol production. The company has built two plants that now are in production—Mid America Bio Energy, North Platte, Nebraska, and CHS-Patriot at Annawan, Illinois, says Raj Mosali, CEO. The MABE plant is using traditional biodiesel technologies with acid and base catalysts in a continuous process, while the CHS-Patriot facility is using Jatrodiesel’s trademarked Super technology, a continuous process with no catalyst.

“Both plants are working well and have met or exceeded our expectations in terms of quality, yields and volume,” Mosali says. “A typical biodiesel plant takes about three to five months to ramp up to a consistently producing plant with concerted effort from the operators and management. The biodiesel production process, like any chemical process, is a multistage process and needs staff that is qualified and trained. Once the plant is at that point, especially a plant using Super, it is a fairly hands-free operation and very robust.”

Colocation advantages are multifold, Mosali notes, and include feedstock availability with no transportation cost, the ability to use glycerin, the biodiesel byproduct, more profitably and reduced costs from the sharing of utilities. He adds that operators are better prepped at a typical ethanol location than a stand-alone biodiesel plant.

The 5 MMgy plant at CHS-Patriot is the first of its kind. Built next to the 130 MMgy CHS-Patriot plant, the multifeedstock biodiesel plant can process up to 13,700 gallons per day.

Jatrodiesel’s Super technology is quite different from the traditional biodiesel process. Jatrodiesel describes its Super technology as a single-stage process that eliminates esterification and transesterification, and puts no limit on free fatty acid (FFA) levels in feedstock. It cuts the cost of traditional biodiesel refining by 25 to 28 percent, the company says, in part by eliminating the need for conventional catalysts.

Feedstock is mixed with methanol and is introduced into the Super column, which operates in a supercritical environment. High temperatures and pressures are maintained in the continuous process and complete conversion takes place in minutes with minimal or no loss in yield, according to Jatrodiesel. The feedstock’s water content has no effect on the process. The mixture coming from the Super column is then sent through a separation process to isolate biodiesel from glycerin, and the excess methanol is recovered. The biodiesel is then either water- or dry-washed to remove excess glycerin.

“Other than the operational savings, some of the other advantages are the ability to use oils up to 100 percent FFA; glycerin byproduct quality of 95 percent or higher, fetching higher price per pound; and a simplicity of operations, making it is easier to train operators. Process related issues are minimal,” Mosali says.

Getting Online
“Patriot was interested in the technology at a very early stage of its development. Once Jatrodiesel built a large pilot (300,000 gallons per year) at its facility in Miamisburg, Ohio, and all the process parameters checked out well, Patriot showed interest in building the plant,” Mosali says.

“There is no precedence in the market for a plant using supercritical technology at these volumes. Due to this plant being the first commercial implementation of the technology, we had to figure out quite a few things at a reasonable price—pumps, instrumentation, reactors, heat exchangers, condensers, boilers, automation, safety related issues and piping.”

The majority of Jatrodiesel’s projects are turnkey projects, but for this one, it implemented on an engineering-only basis.  “We provided all drawings, engineering support, equipment specifications as well as quotes for all equipment, startup, training, HACCP (hazard analysis) support and post startup support, etc., to reduce cost to build the plant,” Mosali says.

“We started testing instrumentation and check backs in February (2015) but then CHS bought Patriot. As with any new acquisition, CHS wanted the project, including the new plant, to conform to all their internal standards. The process delayed the startup by multiple months and eventually we went back into the startup mode in late 2015.”

As with any new technology commercialization, Jatrodiesel encountered a few issues, but fortunately they were small and fixable.

“During the pilot phase we knew the operations would be simple compared to a traditional plant, and on a production basis, when the fact was proved, it was very exciting,” Mosali says. “The system and the process is extremely stable. Due to the elimination of the catalyst, all the related process issues that plague traditional biodiesel plants are gone.

“If something goes wrong in a traditional plant, usually the issues will multiply after that. In the case of Super process, the product is recoverable from any part of the process without any loss of yield and with minimal effort.”

 The CHS plant is slated to use corn oil as its primary source of feedstock, but it will be able to process other feedstocks if, and when, CHS decides to use them, including used cooking oil, animal fats, yellow grease, brown grease, virgin oils, palm oil, coconut oil. Even algae can be processed when it is available in the future in larger volumes.

More plants using the new technology are under development, Mosali reports. Jatrodiesel has just signed a Phase 1 contract with an ethanol producer for a second biodiesel plant using its Super technology.

“We are going through Phase 1 of the process (permitting, etc.),” Mosali says, noting more details will be forthcoming. “We have multiple other ethanol plants that are interested and are in various stages of decision process.”

One other biodiesel plant has come online in the past year. In Madrid, Nebraska, Mid American Agri Products-Wheatland LLC developed its biodiesel technology in-house with the support of an Omaha engineering firm, explains Robert Lundeen, CEO of the 48 MMgy ethanol plant.

The 3 MMgy biodiesel plant was started up in the third quarter of 2015 and has sold biodiesel, although the company is still fine-tuning operations.  The company plans to ramp up or slow down biodiesel production depending on market conditions.

“There are times that we may want to make biodiesel with our corn oil and there are times that it’s best for us to sell our corn oil to the feeding operations around,” Lundeen says, noting that there is good demand from the local feed market for corn oil.
 

Author: Keith Loria
freelance writer
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