BIOGASBiogas test facilityFaculty of Agricultural Sciences, University of Aarhus

The biogas test facility at DJF would be less useful if it did not have a con-tinuous feedstock. Fortunately, DJF is self-sufficient in the supply of nearly any type of feedstock imaginable to the plant. By varying the feed given to DJF’s cows, pigs, sheep, mink and poultry, the manures can be designed to meet the desired end purpose. With more than 500 ha of farmland available we can devise inputs of energy crops using new, conventional and unconventional crops. During the gasification stage we can survey and control the process to a previous-ly unknown level of detail in four independent biogas reactors with outlets for sampling at five levels and with the option of using thermophilic and mesophilic processes. Naturally, all of it will be assiduously monitored and documented. The gas leaving the reactor can be refined, analysed and used to drive a gas engine. The remainder can be sent through a decanter, and the solid frac-tion can subsequently be further processed or applied to farmland for the recycling of nutrients. All of this will be done using scientific monitoring and analysis equipment to document the results. See inside to get an idea of what we call “the facility with boundless bioenergy ideas”.

We have what is needed

We have many good ideas ourselves, but we expect many private enter-prises and institutions will be supplying ideas for projects aimed at both research and commercial sectors. This is why there is an entire test hall available for the use of companies within the biogas sector and for scientists working in this area. We have also built fine office facilities and laboratories, so that all the phases of a test, process or experiment can be carried out with all the faci-lities close at hand.

It is your facility too… A unique biogas test facilityEnergy from renewable resources is the heart of the biogas test facility at the Faculty of Agricultural Sciences, University of Aarhus (DJF). The facility offers unique opportunities for analysing processes and relationships in the production of energy from animal manure, biomass and organic waste products. The facility is one of the most flexible test plants in the world. This gives the Danish biogas sector the chance to lead in the development of new processes, techniques and machinery and hence to generate technology and knowledge of international calibre.

Faculty of Agricultural SciencesBlichers Allé 20

Postboks 50DK-8830 Tjele

Tlf.: +45 8999 1900www.agrsci.au.dk

Energy crops from the field and animal ma-nure from animals. These are the basis for the biogas process that produces heat, po-wer and nutrients. They form the basis for animal feed and for energy crops. In this way

the cycle is closed and another can begin.

Animal manureEnergy cropsWaste products

Biogas facility

Heat and powerNutrients

Closing the cycle

Biogas from farm and fieldThe basis for a biogas production is created on the farm and in the field. The farm ani-mals are fed a mixed ration to produce the manure that is the foundation for a biogas

production. There are also extensive areas at DJF for growing energy crops and the addi-tional facility at the test plant to incorporate animal fat and organic waste products.

Four reactors – full flexibilityThe biogas test plant is actually made up of four independent plants and six experi-mental areas that can run parallel and in-dependent experiments in separate lines.

They are connected in a matrix so that experi-ments can use either different or identical in-puts. The processes can be adjusted in terms of temperature, duration and input.

Experiments, tests and demonstrationsThe four reactors are the heart of the expe-rimental facilities and also where large and small adjustments in an experiment or test are made. Equally important is the test hall, which is divided into six areas and can ac-

commodate experimental set-ups to test equip-ment and processes. The adjoining showroom gives you a panoramic view of the hall from a fully equipped conference room.

Energy and nutrient recycling

Energy crops help increase the energy output from the plant. An area of more than 500 ha is used to grow different kinds of energy crops.

The manure from the pig, cattle, mink and poultry productions at DJF can be made

into different blends. The manure can, for example, be customised in terms of its

nutrient content.

Animal fat and other waste products can be stored and used in the biogas process as needed.

The plant has intensive surveillance and monitoring equipment. The office building contains the laboratory facilities for the day-to-day work at the biogas test facility.

The test hall has space for six experi-mental set-ups for testing equipment and processes. The building also has a showroom with panorama windows, conference facilities and AV facilities.

The end product from the biogas process is really just the beginning of a number of new processes. The biogas can be refined and converted to a biofuel, and the remaining

slurry can be separated into liquid and solid fractions that re-enter the nutrient cycle as soil conditioners, or are made into biofuels with specific nutrients as the only by-product.

With four mixing tanks of 30 m3 each, the input to the reactor is easy to control. There

are also feeders from substrate tanks containing, for example, vegetable or

animal waste products.

The test facility has four reactors – two with a volume of 30 m3 and two

with a volume of 10 m3. They all have capacity to run digestion processes

ranging from mesophilic to thermophilic.

Three post-digester gas tanks store the gas and the slurry for the final gasification process.

The gas is scrubbed and can then either be refined or used in the plant’s CHP unit.

A co-generating facility produces heat and power from the biogas furnished by the test reactors and the actual production unit.

A decanter enables the separation of the manure into liquid and solid fractions that can subsequently be further refined.

LivestockEnergy crops

Substrates

Mixing tanks

Office facilities

Four test reactors

Test hall and showroom

Gas storage

Separation

Heat and power