Europe’s largest US-style ”corn-to-ethanol” plant

Pannonia Ethanol is sited on the west bank of the River Danube outside the town of Dunaföldár in Tolna County about 75 km south of the Hungarian capital Budapest. Dunaföldár is an agricultural community with a population of around 10 000 and Tolna is in the heart of one of the main Hungarian grain producing districts. According to 1990 – 2011 figures from the national statistics office Központi Statisztikai Hivatal (KSH), Hungarian maize production fluctuates between 4 and 9 million tonnes output. However planted acreages, roughly 1 million hectares per annum, have remained almost the same over the period, a reflection of varying yield per hectare in a given year. Furthermore, of approximately 182 000 farms that grow maize, only 10 percent have a farm larger than 20 ha yet these account for 80 percent of the total output. Tolna and neighbouring regions have the largest concentrations of these larger holdings.

US-style corn-to-ethanol

There has not been opposition to Pannonia Ethanol by those whose livelihoods and environment it may impact. On the contrary the local community and the Hungarian government have warmly welcomed the project. Indeed it was given “Special State Supported Project” status by the government on account of its environmental and economic benefits. It is the first project of an Irish American joint venture the Dublin (Ireland) based Ethanol Europe Renewables Ltd, EERL. Formed in 2010, EERL is owned by the family of former Irish property developer Mark Turley and the family of Granite Falls, Minnesota based ethanol plant builder Ron Fagen. Groundbreaking took place in August 2010 and 20 months later, in April 2012, the plant began operation. Today, the plant has an annual nameplate capacity to processing 650 000 tonnes of feed maize into 280 000 m³ ethanol and 160 000 tonnes of dried distillers grains and solubles (DDGS).

The overall design, engineering, procurement and construction (EPC) was carried out by Fagen Inc. via its subsidiary Fagen Europe LLC. All the process equipment was manufactured in the US with necessary European standard adaptations, for instance electrics, and shipped to Hungary. It is the first overseas installation for Fagen.

The plant utilises a closed-loop dry mill process technology developed by another US company, ICM Inc., a privately held US agricultural engineering company with proprietary food and feed technologies based in Colwich, Kansas. The dry mill process is widely used in US corn-to-ethanol plants. Fagen is a licensed ICM technology partner and has been involved in the construction of over 90 dry mill ethanol plants in the US.

In dry milling the entire grain kernel is ground into flour and put through the fermentation process whereas wet milling involves separating the grain kernel into its constituent components; germ, fibre, protein and starch prior to fermentation.

Local feedstock

The feedstock used is non-GMO (genetically modified organism) maize majority sourced from within a 100 km radius of Dunaföldár and delivered by truck to a colocated grain storage terminal. Sited on the riverbank, this terminal is owned and operated by Cargill Hungary, a subsidiary of global agro-industrial major Cargill. The terminal has a 30 000+ tonne grain storage capacity, about 15-20 days worth of feedstock, as well as river barge loading facilities for the DDGS produced by Pannonia.

– We use only non-GMO feedstock, most of which is grown in Hungary. This is very important to us as verified GMO-free DDGS, our main co-product, commands a significantly higher price, commented Ferenc Jánoki, Production Manager, Pannonia Ethanol. He explained that the company has its own sourcing staff that deal directly with farmers as well as grain suppliers. The minimum feedstock purchase contract is for a single truckload, about 25 tonnes.

– This means that practically every arable farmer in the region, regardless of farm size, has the opportunity to be a potential supplier in a given season, said Jánoki.

In other words Pannonia in itself is not expected to have any notable effect on the existing Hungarian farmland ownership structure, a point highlighted in an “Economic Impact Study” published in July 2012 by HÉTFA Center for Analysis.

Simultaneous saccharification and fermentation

The maize is conveyed from the Cargill terminal, screened to remove any foreign objects and contaminants and then milled into a flour by hammer mills. Recycled process water and enzymes are added to the milled grain in slurry tanks along with recycled water, thin stillage, from the post-distillation centrifuges. In the slurry tanks a reaction known as starch gelatinisation occurs. The process is further enhanced by use of a selective milling whereby the slurry is pumped through a separation device that separates and regrinds any remaining solids before returning it to the process stream.

Hydrolysis of the gelatinised starch into glucose, takes place in the liquefaction tanks. The process results in mash, which is then pumped to fermentation tanks where simultaneous saccharification and fermentation takes place. A glucoamylase enzyme breaks down the dextrins to form  simple sugars (saccharification) and added yeast converts the sugars into ethanol and carbon dioxide (CO₂).

– The actual fermentation takes 50-60 hours and results in a “beer” with about 15 percent ethanol by volume along with grain and yeast residues, said Jánoki.

The “beer” is pumped into one of three multi-column distillation units to separate the water with non-fermentable residues, referred to as whole stillage, from the ethanol.

– The ethanol leaving the distillation columns is approximately 95 percent by volume. A molecular sieve system removes the remaining water bringing it to 99 percent or higer, explained Jánoki.

The fuel-ready ethanol is then pumped to one of two 9 000 m³ onsite storage cisterns.

Corn oil and protein

The whole stillage is transferred from the bottom of the distillation columns to centrifuges to separate the solids, as a wet cake, from the liquid. The moisture content of the wet cake is around 60-65 percent. The remaining liquid, thin stillage contains about 5-10 percent solids and part is recycled back to the slurry tanks at the start of the process. The remaining volume of thin stillage is sent to the evaporators where it is concentrated into syrup containing 25-50 percent solids. The syrup, which is high in protein and fat content, is mixed back with wet cake, resulting in the product called wet distillers grains and solubles (WDGS).  WDGS is suitable for use as a fresh high-protein animal feed ration.

– A feature here is a corn oil recovery step. The idea is to recover the oil from the syrup prior to it being mixed with the WDGS, revealed Jánoki, adding that the non-food grade oil can be used as an animal feed ingredient or feedstock for producing biodiesel.

Consisting of a tricanter system and an emulsion concentrate breaker, the system separates and recovers the oil from the post-fermentation syrup stream as it leaves the evaporators. The oil is then pumped to settling tanks where the majority of any residual solids and are wax-bound oil have settled out and pumped back to the process.

To increase shelf life and transportability, around three quarters of  WDGS is conveyed to a drum dryer and converted into Dry DGS(DDGS), a high value product with 10-14 percent moisture content.

– Our Pannonia Gold DDGS is a top-quality GMO-free Hungarian animal feed, remarked Ferenc Jánoki.

Expansion in progress

From day one the plant was designed and built with capacity expansion in mind. Construction on the 12 ha site is already well underway for a doubling of production to 450 000 m³ ethanol per annum which will make Pannonia the single largest ethanol plant in Europe.

The Pannonia Ethanol project has represented to date an overall investment of around EUR 200 million, and it has received project finacing by US, Canadian and Hungarian lenders. It includes a gas-fired combined heat and power plant which supplies the process heat along with some of the electricity needs. Operating 24/7 the plant employs around 120 staff three times the number compared to a US plant of a similar capacity.

– We have our own grain purchasing staff as well as our own ethanol and DDGS sales staff. In accordance with Hungarian customs and excise regulations the entire site is fenced-off and has to have 24 hour manned surveillance, remarked Ferenc Jánoki.

A change compared to the original plant is that the French company Maguin from Saint-Quentin has been selected to supply the third DDGS dryer. A triple-pass turbo dryer, it has multiple energy coupling and heat recovery integrated across the second ethanol and DDGS production line. According to Maguin the overall energy consumption of the new process line will be about 32 percent less than the original process line ensuring that the future facility complies with the latest EU requirements for greenhouse gas (GHG) reduction. The new line is scheduled to start up this year.

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