Biochain Study tour Review
Partners:
 Danish Research Partners:
o University Southern Denmark (SDU)
WP0 leader, WP2 leader,
WP3 partner (PhD) and WP4. (Post Doc)
o Technical University of Denmark (DTU-M)
WP1 leader and WP2 participants.
o Technical University of Denmark (DTU-E)
WP3 leader and WP2 partner.
o University of Copenhagen
WP4 leader andWP2 participant.
o University of Aarhus (AU)
WP4 partner and WP2 partner.
o Knowledge Centre for Agriculture
WP5 leader and WP2 partner.
 Industrial Partners:
o Fredericia Spildevand A/S
WP1 partner and WP2 partner.
o Energinet-DK
WP1 partner and WP2 partner
o Maabjerg Energy Concept (MEC) :
WP1 partner and WP2 partner.
Visited Plants
1. Fredericia Wastewater Treatment and Biogas Plant
2. Foulum Biogas Plant and Research Center
3. Maabjerg Biogas Plant
Fredericia Wastewater Treatment and Biogas Plant
Figure1: Fredericia and Fredericia wastewater treatment plant (Reference: presentation of
Annemarie Gotfredsen during the Biochain tour, 2013/01/23)
Fredericia wastewater plant is the one of the largest wastewater treatment plants in
Denmark. In 2014, they are one of Denmark's 10 best performing companies
measured by the Supply Secretariat benchmark. The large amounts of discharging
waste water around 9.3 million m3 mainly comes from industries, dairy and oil
company. Inlet is 65% from industries like dairy and oil company and the rest is from
household wastes. This plant produced 6900 tons of dewatered sludge, 25% TS in
the last year. The total number of employees working in the administration,
transport, wastewater and piping operation sections are 34. There is an overall
treatment process drawn in the next page.
Before visiting the whole treatment process Annemarie Gotfredsen, the director,
gave a presentation including the information, aims and challenges.
Their visions are:
1. To become energy neutral before 2019
2. To become a refinement facility
3. To increase the biogas production (30%)
Removing Big Stuff
Biological treatment:
Settlement
Aerobic and Anaerobic
Biogas Plant
Sludge Treatment
The total capacity and average load are 420000PE and 286000PE respectively. There
are two biogas plants of 2000 m3 for each one producing totally 1.7 milliom m3
anually. The plants are working under mesophilic condition, 40°C and 35 days
hydrolic retention time. Before selling energy to DONG they have been producing
500000 KWh and after entering into partnership with DONG Energy in 2008, they
purchased of surplus biogas and Upgrading system to natural gas quality.
Annual turnover is about 100 million DKK. Fixed investment is 2.5 million DKK, 2.2
millin DKK for wiring and 0.3 million DKK for purification plant.
Now, their focusing areas are power, gas production, water and heat and they are
going to decrease the electricity, water and heat and increase the gas production.
One of the issues that they are going to deal with is that the outlet contains
ammonia and phosphorous should have been treated.
Foulum Biogas Plant and Research Center
Foulum Research Center is a part of Aarhus University and the main fields of the
research are in animal husbandry and plant production. Furthermore, Foulum
carries out a large part of the interdisciplinary research, i.e. ecology, animal
husbandry production and welfare. In the area of animal husbandry the facilities
include livestock buldings, livestock/herds, a food stuff factory and a
slaughterhouse. Research into cattle, pigs, mink, sheep and poultry is emphasized.
The areas of plant production include facilities for experimental cultivation as well as
research in applied cropping systems and specialized facilities. They are also working
on greenhouse gas emission and biogas production and there is a biogas plant in the
Foulum.
Figure 2: Foulum Research Center, (Reference:
http://agritechblog.files.wordpress.com/2011/11/au-djf.jpg)
At the first Søren O. Petersen gave a presentation about his research and areas
regarding greenhouse gas emission and specially N2O from a variety of slurries and
digestates. After the presentation we went to visit the biogas plant in Foulum.
The biogas plant is working under thermophilic condition, 50°C and 14 days hydrolic
retention time. The capacity of the digester is 1100 m3 and they uses animal manure
as a main substrate and straw as a co-substrate. The pretreatment is used to crush
the straw by extruder.
They are also working on methane production from pure culture by hydrogen and
carbon dioxide on pilot scale with collaboration of the university from USA.
Maabjerg Energy Concept and Biogas Plant
The Maabjerg Energy Concept envisions creating a comprehensive, sustainable
energy solution, based on local and CO2-neutral raw materials, by using the latest
technologies. The project merges several energy supply objectives in a holistic
system concept, where the synergy between the individual solutions is used
optimally and with great effectiveness, through the utilization and alignment of
energy streams between the individual plants
Figure 4: Maabjerg Energy Concept
The Maabjerg biogas plant is the largest biogas plant in Denmark and one of the
largest biogas plants in the world and for construction of the plant they did not
received any subsidy. One of their big challenges was to satisfy the people living
near the plant that there will not be any odor due to the plant and traffic owing to
transportation and trucks. The number of employees working in the biogas plant
except truck drivers is 10 and 4000 sensors has been using to control the whole
plant keep it in stable condition.
There are two lines for feeding, green line and sludge line. The green line is fed with
550000 tons of manures, 120000 tons of biological industrial waste and 2000 tons of
crops and totally would be 672000 tons per year. The sludge line treats 120000 tons
per year of sewage sludge containing 3.5% solids. The organic nitrogen and
phosphorous input is 780 and 585 tons per year respectively.
Figure 3: Maabjerg Biogas Plant (Reference:
http://ethanolproducer.com/articles/9173/denmark-sets-high-goals-for-renewables)
The transportation should be less than 50 km and the five trucks similar to dairy
trucks are used for this purpose and one more is required. The trucks are supported
by driving company.
The digestion condition is mesophilic, 37˚C and 23 days hydrolic retention time. The
volume of digester is 8000 m3 and annual biogas production is 18 million m3. Before
the feed goes to the digesters, it is heated to 73°C. After digestion, digestate goes to
the tanks for storage to release the excess biogas about 10% of whole biogas. Then
the liquid and solid phase separated from each other by centrifuges.