A little bit about the Research Centers in Germany…

Energy from biomass?

Yes, it is possible!

On the morning Monday of May 20th, EM42 fellows headed to the central station of Dresden, bound for the beautiful city of Leipzig. After a short trip and a small break, at 1 pm they arrived at the “German Centre for Biomass Research (DBFZ)”.

During the visit to DBFZ, they learned about the different processes to produce energy from biomass; and after a short explanation about the organization with international colleagues from China, Spain, Canada, Brazil, and Italy and the vision of sustainable resource basis, smart bioenergy – innovations for a sustainable future, they proceeded to visit its installations and laboratories that are divided into five departments: biogas, refinery, hydrothermal carbonization, heating technologies, and wood combustion.

Additionally, they had the opportunity to meet some of the researchers of the institution, as they explained to them; DBFZ with approximately 250 employees researches how to generate energy from biomass resources. In this regard, DBFZ works in joint collaboration with public and private institutions around the world.

Something that 30 years ago seemed impossible, now is a reality thanks to institutions like DBFZ that bet on studies based on the applied researches that develop practical solutions to current problems related to the integrated bioenergy provision.

The second day in Leipzig at 09:30am, EM42 fellows arrived at the “Helmholtz Centre for Environmental Research (UFZ)”, they were welcomed by Mr. Andreas Staak who introduced the visitors the UFZ installations, along the day some researchers explained in more detail the projects that UFZ is developing; as is the case of the “Center for Advanced Water Research (CAWR)” presented by Prof. Olaf Kolditz and Mr. Lars Bilke from the Visualization Laboratory; whom explained some projects developed for Asia (China and Jordan) related to water sustainability, at that time, the 3D animation developed by UFZ for the spatial planning was one of the most incredible experience that the fellows tried that day.

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After the lunch at UFZ canteen, Prof. Martin Volk presented the topic “Assessing and governing synergies between food production, biodiversity, and ecosystem services”; Additionally the Department of Urban and Environmental Sociology and the Department of Ecological Modelling presented some of the projects that UFZ is developing related to food-waste-energy sustainable environment; and impacts of the new policy instruments, technologies and change processes on pastoral land use as a social-ecological modeling approach.

Finally, the fellows had the opportunity to enjoy the game “NomaSed” developed by the Department of Ecological Modelling in order to create awareness to the stakeholders about the land use in agriculture activities. Of course, there were winners in this game!

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Time was relative short those days, however, the fellows tried to spend time together with a big Vietnamese dinner in the beautiful city of Leipzig during their free time.

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See you soon beautiful Leipzig!

by Ms. Magaly Beltran (Bolivia) and Ms. Tam Thanh (Vietnam)

The “sweet smelling” odor of the waste water treatment plant …

… an excursion to Stadtentwässerung Dresden.

CIPSEM course participants usually look forward to excursions because they provide more visual and practical learning which goes beyond the theoretical knowledge transfer that happens in the seminar room. However, prior to departure for this excursion to the Wastewater Treatment Plant (WWTP), EM-42 participants had mixed feelings as they feared stench from the plant while also excitedly anticipating the adventure of seeing the WWTP function in real time.

It was one of the beautiful days in Dresden with the sun shining brightly and a warm weather. Some participants dressed up in their least favorite clothes while some took “stench mitigation weapons” like tangerine to protect against the anticipated “sweet smelling” odor of the WWTP. On arrival at Stadtentwässerung Dresden, Mr. Sebastian, Public Relations Officer at the facility, highlighted some of the basic rules of the facility like no touching of barriers, no eating and drinking, wash hands at exit, etc. Additionally, it was learnt that this WWTP began its operation in 1910 and sits on 23 hectares of land. More interestingly, sewers used in the last century, dating back to 1888 were on display and are clearly different with open sewer systems whereas the 1900s had closed sewer systems, perhaps this could be described as evolution of the sewers! Interesting points to note, the plant was automated since 100 years ago and the distance of the sewerage is about 1800 km. The WWTP collects about 160000m3 of wastewater per day in addition to rain water because it is a combined system.

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Anaerobic digesters sighted in Stadtentwässerung Dresden, WWTP (photo by Ms. Haili Zhou)

The first step of the facility was shown, that is Neustadter Kanal, where the waste water flows in from the sewerage system of Dresden city. The next step, which is the mechanical treatment involved screening large objects like plastics, tissue towels, etc. in a series rack. At this point, the intensity of the stench was so strong that participants made “eew” sounds, many adopted the weapon of stench mitigation approach, while some covered their nose with one hand and at the same time, took pictures with the other (there was no giving up!). But then, the faeces should not be accused here because as revealed, it is the fats that stink the most! It was really interesting to see the screening bars working and being fully automated, no workers were seen. Furthermore, the channel where dense material such as sand or broken glass settles are removed through suction to prevent wear and tear of mechanical parts of the WWTP and a series of water distribution pumps of varying capacities were also sighted. After that was the primary sedimentation tanks where the suspended materials are removed using gravity. The denser sediments sink while the lighter ones like oils floats on the water. Also, the sludge at bottom of the sedimentation tanks and the floating scum are scraped and pumped into the anaerobic digesters for secondary wastewater treatment.

The next phase of the excursion involved learning about the biological treatment of wastewater through the activated sludge process. The reactors are the first step and here the participants met the Very Important Persons (VIPs) of this process who are also the most hardworking entities. They are called microorganisms! These nice bugs (mostly bacteria) were kept aerated with sufficient oxygen needed to breakdown organic matter (i.e. ammonia) in wastewater to nitrates. This aerobic process called nitrification produces nitrates rich water that could pollute water bodies if discharged without removal of the excess nitrates. Following this step was the denitrification process in which nitrates are reduced to gaseous nitrogen by facultative anaerobes like fungi in anoxic conditions.

From the biological treatment (both aerobic and anaerobic), the treated water is circulated to aeration tanks and then to the clarifier tanks. Remarkably, anaerobic digesters were sighted at a distance in the facility where sludge is channeled for biogas production which feeds into electricity generators. It was very impressive to learn that Stadtentwässerung Dresden generates 80% of its energy demand from renewable resources. Specifically, about 18000 MWh was said to be from the digestion towers. At the final clarifiers, the treated water is discharged into the Elbe river at a rate of 120000 m3 per day where discharging pipe is fitted with turbine that generates about 680 MWh of electricity. The highpoint of the day was the sighting of solar panels in the facility that generates about 160 MWh annually. At this point, participants totally forgot about the oozing stench of fresh wastewater and it was all about different postures for pictures – interessant!

The benefits of a WWTP cannot be overemphasized because, hygiene is very important to every citizen as well as; water resources protection and flood protection. Moreover, discharging untreated waste water into urban lakes or rivers would have detrimental effects, not only on the environment but also on the living organisms. Amidst the fears of odor from the WWTP, the participants gained practical knowledge that could be applied in their home countries. Hence, it was mission accomplished!

The entire EM42-fellows were grateful for the opportunity to visit a WWTP and this appreciation goes to Mr. Sebastian (Stadtentwässerung Dresden), Prof. Dr. P. Krebs (Institute for Urban Water Management, TU-Dresden) Mr. Roman Kiesshauer and all CIPSEM staff team, UNEP, UNESCO & BMU for all the support granted for a successful excursion to the treatment plant. The “sweet smelling odor” was not so bad after all. In fact, it was worth it!

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The excursion guide, Mr. Sebastian (left), Mr. Roman Kiesshauer (back) with EM42-Participants at the Stadtentwässerung Dresden WWTP (photo by Ms. Sreymoch Bun)

by Ms. Iquo Offiong (Nigeria)

Excursion to the Saxon Dam Authority and Ecological Research Station Neunzenhain

Authors: Ahimbisibwe Alfred (Uganda) and Clement G Tweh (Liberia)

“Water is Life”

You wake up in the morning some minutes late and you decide to rush through your preparation to be in time for the office. You rush to the bathroom, open the tap and lo… there is no water flowing. Your mind switches to panic mode. Can you go to the office without taking a bath? Or even without brushing your teeth?

This is a disastrous situation that the Saxon Dams Authority strives to avert by ensuring that there is always sufficient supply of high quality drinking water available to households and industry at any time all year round. Participants in the 41st Postgraduate Course of Environment Management for Developing and Emerging countries held an excursion to the Saxon Dams Authority’s drinking water reservoirs in Neunzenhain on 3rd and 4th May 2018 to learn about drinking water supply.

Two staff members of the Saxon Dam’s Authority and Dr. Lothar Paul of the Ecological Station Neunzenhain conducted the excursion. The Saxon Dams Authority manages fresh water resources in the Free State of Saxony of which dams make up 20%, the rest being rivers. They are in charge of 153 reservoirs, 23 of which are for drinking water and the rest for flood control. They also supply drinking water to 40% of Saxony’s population with storage capacity of 100 million m3 of water.

Participants were informed that the Saxon dams Authority supplies drinking water to six regional contractors who distribute water in the various cities in the state. In order to balance demand and supply, some dams are interconnected through tunnel systems or open channels and that the water quality has significantly improved due to strict requirements for purification of flue gas from coal power stations and industries that were previously responsible for acid rain.

Talsperre Neunzenhain II

Neunzenhain dams were constructed to provide drinking water for the city of Chemnitz, which was growing rapidly due to industrialization in the 19th Century. The first dam was built between 1891 and 1893 while Neunzenhain II was built between 1911 and 1914 using natural stones from the region. It is gravity dam whose weight of stones holds back the water. To avoid siltation in this dam, two pre-dams built upstream reduce the sediment load of incoming water. Secondly, 25 km² of the dam’s catchment area is forested giving it the best quality of water. The rivers flowing these forests also carry little sediments. However, every 10 years the Dams Authority does a general de-silting operation to maintain the capacity of the dam.

The Neunzenhain II dam was extensively repaired between 1996 and 2000 making it more robust with more monitoring devices to ensure its life is extended. During these works, a new concrete was built behind the stone wall and a monitoring tunnel also constructed. Important parameters monitored include

  1. Pressure: Due to high pressure in the water column, water tends to escape below the wall. To mitigate this, ground water below the dam wall is sucked out and drained away.
  2. Dam displacement: Due to alternating seasons, there is dam displacement especially in summer due to temperature difference on both sides of the dam. A maximum displacement measured is 8mm.

Water can be drawn from five different layers in the reservoir and such thermo-stratification allows for continuous supply of clear water even if silted water enters the dam by drawing water from lower layers, which actually remain clear.

Ecological Research Station Neunzenhain

Participants visited the Ecological Research Station in Neunzehain which was established in 1959 focus on research on drinking water reservoirs. This was after a realization that activities in the surrounding areas of the dams affect the quality of water. It was founded as a hydro-biological field station and they have collected a lot of ecological data on reservoirs.

Dr. Lothar Paul and Ms. Henrike Beesk presented research that is going on at the station on Cyano bacteria in the drinking water reservoirs and other micro organism such as phytoplankton, zooplankton and fish. Cyanobacteria produce toxins which can cause sickness and death in severe circumstances. The team also presented ecological interventions used to maintain the quality of water such as bio-manipulation and sanitization of the catchment. Bio-manipulation involves stocking of predator fishes in the reservoirs such as pike and trout to hunt the smaller fishes thus favouring growth of zooplankton which in turn reduce the phytoplankton that degrade water quality.

Emerging Issues

  1. Per capita water demand in Saxony has reduced from 200 m3 to 85 m3 and this is attributed to increased efficiency in use and change in industry to less water intensive industry
  2. To increase forest resilience, broad leaf tree species have been introduced to the previous coniferous monoculture and this diversity improves forest productivity and resilience.

Visiting the wastewater treatment plant Dresden-Kaditz

By Liu Haibo, China

Today we visited the wastewater treatment plant Dresden-Kaditz. Although the weather conditions were not beautiful with wind and rain, the EM40 course participants still happily visited the unit. This unit, as the only municipal sewage treatment plant in the area, has a long history but is maintained well and orderly. Although conventional sewage treatment technology is used, the plant is unique in its design / operation and management. Moreover the processing indicators can meet the management requirements.

Photos: T. Karp / Liu Haibo

Mr. Lucke, the head of the environmental analysis laboratory at the wastewater treatment plant, guided us along the treatment process, and explained the different treatment steps from inflow to coarse and fine screens to the different clarification tanks and sludge treatment. Seeing the huge groundwater pipes, we could feel our gap with Germany not only on the ground, more perhaps we can not see the place. During the visit, the participants were able to ask questions about the treatment process, the rainwater impact,and so on.

Excursion to the Ecological Station Neunzehnhain

By Louisa Chinyavu Mwenda (Kenya)

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Reservoir at the TUD Ecological Station Neunzehnhain

On 15th September 2016, the participants of the 68th UNEP/UNESCO/BMUB International Short Course on Integrated Water Resources Management and Health set out for the ecological station in Neunzehnhain.  Along the way from Dresden to the station, I observed that land is mainly characterized as large farms, and as we approached Neunzehnhain, the area becomes hilly and forests are abundant! When we arrived at the station, we were welcomed with breath taking views of the dam with an amazing forest backdrop (I shared the above picture with my friends back home and two suggested that area looks like a good “honeymoon” location!).
We were lucky to have a chance to get in deep within the dam, 30 meters deep to be precise, where we experienced a cool 6 degrees! Unfortunately for security reasons, we were not allowed to take pictures inside the dam. When we were done with the dam, we headed back to our new “home” to settle and rest… or preferably described as catching up! At the center there is no mobile network coverage and also no wifi, which I think worked okay as it promoted group dynamics and the participants bonded more with each other, discussing various cultural differences majorly on song and dance! The area is tranquil and serene, which is good for relaxing! Dr. Paul welcomed us heartily, such a charming man he is, and an expert too in water! We had a tantalizing meal with fresh fish (my favorite!) among other varieties. We also learned that one of the participants is a talented pianist and he entertained us with one piece before we left for bed. The next morning we had an interactive session on microbiology and we had the chance to actually be hands-on at the lab, which was exciting and very interesting especially to see some of the micro-organisms in the water samples. At about midday, we then set off to the Ore Mountains, at a restaurant where we had lunch facilitated by CIPSEM; and after we proceeded to other dams within the area, guided by Dr. Paul, for another session on water reservoirs before we left for Dresden.

Visit at the Junior Research Group INOWAS

The group left Dresden upstream the river Elbe to Pirna, as there is a TU Dresden outpost of the hydro-sciences department to visit the Junior Research Group INOWAS. The project is funded by the German Federal Ministry of Education and Research and runs until 2018. The research group around our host Dr. Catalin Stefan aims at providing stakeholders with a scientifically based decision support system for planning, design and management of applications in the water sector. The focus lies on the qualitative and quantitative assessment of the managed groundwater reservoirs by means of scenario analysis, prognosis and risk assessment and with regard to the influencing climatic factors. More information on the research can be found on their website: https://tu-dresden.de/bu/umwelt/hydro/inowas

(Photos: T. Karp)

Excursion to the DREWAG Drinking Water Purification plant at Dresden Tolkewitz

By Binh Pham Doan Thanh (Vietnam)

13 September, we had the next interesting excursion to Waterworks Tolkewitz, which was  built about one hundred years ago. It is placed on the left bank of the Elbe River and uses the river water as a source for producing drinking water. At the plant we were welcomed by the former head of the Water works Tolkewitz, a very kind and experienced man. During the following hour he explained the formation and development of the drinking water supply system of Dresden. After that, we visited the drinking water treatment area. The pipe system is completely isolated from the external environment to make sure that the water will always meet all standards and norms. It was a system worth learning. Finally, I would like to thank Dr. André Lindner for his translation work during the whole excursion.