@techreport{ChristGrossRenz1998, author = {Christ, Ansgar and Groß, Rolf Fritz and Renz, Ulrich}, title = {HGR: Untersuchung zur Minimierung von gasf{\"o}rmigen Schadstoffen aus Rauchgasen bei der Heißgasfiltration}, doi = {10.2314/GBV:504318411}, pages = {141 Seiten}, year = {1998}, abstract = {Gas- und Dampfturbinen-Kraftwerke mit Druckwirbelschicht- oder mit Druckvergasungsverfahren erm{\"o}glichen die Verstromung von Kohle mit hohem Wirkungsgrad und niedrigen Emissionen. Eine Voraussetzung f{\"u}r den Betrieb dieser Anlagen ist die Entstaubung der Rauchgase bei hohen Temperaturen und Dr{\"u}cken. Abreinigungsfilter mit keramischen Elementen werden dazu eingesetzt. Eine Reduzierung gasf{\"o}rmiger Schadstoffe unter den gleichen Bedingungen k{\"o}nnte Rauchgasw{\"a}sche ersetzen. Ziel des Gesamtvorhabens ist es, die Integration von Heißgasfiltration und katalytischem Abbau der Schadstoffe Kohlenmonoxid, Kohlenwasserstoffe und Stickoxide in einen Verfahrensschritt zu untersuchen. Die Arbeitsschwerpunkte dieses Teilvorhabens betreffen: die katalytische Wirkung eisenhaltiger Braunkohlenaschen, die Wirksamkeit des Calciumaluminat als Katalysator des Abbaus unverbrannter Kohlenwasserstoffe im Heißgasfilter, numerische Simulation der kombinierten Abscheidung von Partikeln und gasf{\"o}rmigen Schadstoffen aus Rauchgasen}, language = {de} } @article{CheenakulaPaulsenOttetal.2023, author = {Cheenakula, Dheeraja and Paulsen, Svea and Ott, Fabian and Gr{\"o}mping, Markus}, title = {Operational window of a deammonifying sludge for mainstream application in a municipal wastewater treatment plant}, series = {Water and Environment Journal}, journal = {Water and Environment Journal}, number = {Early View}, publisher = {Wiley}, address = {Chichester}, issn = {1747-6593}, doi = {10.1111/wej.12898}, pages = {1 -- 12}, year = {2023}, abstract = {The present work aimed to study the mainstream feasibility of the deammonifying sludge of side stream of municipal wastewater treatment plant (MWWTP) in Kaster, Germany. For this purpose, the deammonifying sludge available at the side stream was investigated for nitrogen (N) removal with respect to the operational factors temperature (15-30°C), pH value (6.0-8.0) and chemical oxygen demand (COD)/N ratio (≤1.5-6.0). The highest and lowest N-removal rates of 0.13 and 0.045 kg/(m³ d) are achieved at 30 and 15°C, respectively. Different conditions of pH and COD/N ratios in the SBRs of Partial nitritation/anammox (PN/A) significantly influenced both the metabolic processes and associated N-removal rates. The scientific insights gained from the current work signifies the possibility of mainstream PN/A at WWTPs. The current study forms a solid basis of operational window for the upcoming semi-technical trails to be conducted prior to the full-scale mainstream PN/A at WWTP Kaster and WWTPs globally.}, language = {en} } @article{CheenakulaHoffstadtKrafftetal.2022, author = {Cheenakula, Dheeraja and Hoffstadt, Kevin and Krafft, Simone and Reinecke, Diana and Klose, Holger and Kuperjans, Isabel and Gr{\"o}mping, Markus}, title = {Anaerobic digestion of algal-bacterial biomass of an Algal Turf Scrubber system}, series = {Biomass Conversion and Biorefinery}, volume = {13}, journal = {Biomass Conversion and Biorefinery}, publisher = {Springer}, address = {Berlin}, issn = {2190-6823}, doi = {10.1007/s13399-022-03236-z}, pages = {15 Seiten}, year = {2022}, abstract = {This study investigated the anaerobic digestion of an algal-bacterial biofilm grown in artificial wastewater in an Algal Turf Scrubber (ATS). The ATS system was located in a greenhouse (50°54′19ʺN, 6°24′55ʺE, Germany) and was exposed to seasonal conditions during the experiment period. The methane (CH4) potential of untreated algal-bacterial biofilm (UAB) and thermally pretreated biofilm (PAB) using different microbial inocula was determined by anaerobic batch fermentation. Methane productivity of UAB differed significantly between microbial inocula of digested wastepaper, a mixture of manure and maize silage, anaerobic sewage sludge, and percolated green waste. UAB using sewage sludge as inoculum showed the highest methane productivity. The share of methane in biogas was dependent on inoculum. Using PAB, a strong positive impact on methane productivity was identified for the digested wastepaper (116.4\%) and a mixture of manure and maize silage (107.4\%) inocula. By contrast, the methane yield was significantly reduced for the digested anaerobic sewage sludge (50.6\%) and percolated green waste (43.5\%) inocula. To further evaluate the potential of algal-bacterial biofilm for biogas production in wastewater treatment and biogas plants in a circular bioeconomy, scale-up calculations were conducted. It was found that a 0.116 km2 ATS would be required in an average municipal wastewater treatment plant which can be viewed as problematic in terms of space consumption. However, a substantial amount of energy surplus (4.7-12.5 MWh a-1) can be gained through the addition of algal-bacterial biomass to the anaerobic digester of a municipal wastewater treatment plant. Wastewater treatment and subsequent energy production through algae show dominancy over conventional technologies.}, language = {en} } @article{CheenakulaGriebelMontagetal.2023, author = {Cheenakula, Dheeraja and Griebel, Kai and Montag, David and Gr{\"o}mping, Markus}, title = {Concept development of a mainstream deammonification and comparison with conventional process in terms of energy, performance and economical construction perspectives}, series = {Frontiers in Microbiology}, volume = {14}, journal = {Frontiers in Microbiology}, number = {11155235}, editor = {Huang, Xiaowu}, publisher = {Frontiers}, issn = {1664-302X}, doi = {10.3389/fmicb.2023.1155235}, pages = {1 -- 15}, year = {2023}, abstract = {Deammonification for nitrogen removal in municipal wastewater in temperate and cold climate zones is currently limited to the side stream of municipal wastewater treatment plants (MWWTP). This study developed a conceptual model of a mainstream deammonification plant, designed for 30,000 P.E., considering possible solutions corresponding to the challenging mainstream conditions in Germany. In addition, the energy-saving potential, nitrogen elimination performance and construction-related costs of mainstream deammonification were compared to a conventional plant model, having a single-stage activated sludge process with upstream denitrification. The results revealed that an additional treatment step by combining chemical precipitation and ultra-fine screening is advantageous prior the mainstream deammonification. Hereby chemical oxygen demand (COD) can be reduced by 80\% so that the COD:N ratio can be reduced from 12 to 2.5. Laboratory experiments testing mainstream conditions of temperature (8-20°C), pH (6-9) and COD:N ratio (1-6) showed an achievable volumetric nitrogen removal rate (VNRR) of at least 50 gN/(m3∙d) for various deammonifying sludges from side stream deammonification systems in the state of North Rhine-Westphalia, Germany, where m3 denotes reactor volume. Assuming a retained Norganic content of 0.0035 kgNorg./(P.E.∙d) from the daily loads of N at carbon removal stage and a VNRR of 50 gN/(m3∙d) under mainstream conditions, a resident-specific reactor volume of 0.115 m3/(P.E.) is required for mainstream deammonification. This is in the same order of magnitude as the conventional activated sludge process, i.e., 0.173 m3/(P.E.) for an MWWTP of size class of 4. The conventional plant model yielded a total specific electricity demand of 35 kWh/(P.E.∙a) for the operation of the whole MWWTP and an energy recovery potential of 15.8 kWh/(P.E.∙a) through anaerobic digestion. In contrast, the developed mainstream deammonification model plant would require only a 21.5 kWh/(P.E.∙a) energy demand and result in 24 kWh/(P.E.∙a) energy recovery potential, enabling the mainstream deammonification model plant to be self-sufficient. The retrofitting costs for the implementation of mainstream deammonification in existing conventional MWWTPs are nearly negligible as the existing units like activated sludge reactors, aerators and monitoring technology are reusable. However, the mainstream deammonification must meet the performance requirement of VNRR of about 50 gN/(m3∙d) in this case.}, language = {en} } @incollection{ChansonBungMatos2015, author = {Chanson, Hubert and Bung, Daniel B. and Matos, J.}, title = {Stepped spillways and cascades}, series = {Energy dissipation in hydraulic structures / Hubert Chanson (ed.)}, booktitle = {Energy dissipation in hydraulic structures / Hubert Chanson (ed.)}, publisher = {CRC Press}, address = {Boca Raton, Fla. [u.a.]}, isbn = {978-1-138-02755-8 (print) ; 978-1-315-68029-3 (e-Book)}, pages = {45 -- 64}, year = {2015}, language = {en} } @inproceedings{BuehlerLeandroBungetal.2015, author = {B{\"u}hler, P. and Leandro, J. and Bung, Daniel B. and Lopes, P. and Carvalho, R.}, title = {Measuring void fraction of a stepped spillway with non-intrusive methods using different image resolutions}, series = {2nd International Workshop on Hydraulic Structures : Data Validation : Coimbra, Portugal, 8-9 May 2015}, booktitle = {2nd International Workshop on Hydraulic Structures : Data Validation : Coimbra, Portugal, 8-9 May 2015}, organization = {International Workshop on Hydraulic Structures : Data Validation <2, 2015, Coimbra>}, pages = {1 -- 8}, year = {2015}, language = {en} } @incollection{BurgerKirschMarcheretal.2014, author = {Burger, Ulrich and Kirsch, Ansgar and Marcher, Thomas and H{\"o}ser, Sebastian}, title = {Geologisch-geotechnischer Planungsprozess von Tunnelbauten mit Schwerpunkt tiefliegender Tunnel}, series = {Beton-Kalender ; Bd. 103: Unterirdisches Bauen, Grundbau, Eurocode 7}, booktitle = {Beton-Kalender ; Bd. 103: Unterirdisches Bauen, Grundbau, Eurocode 7}, publisher = {Ernst}, address = {Berlin}, isbn = {978-3-433-03051-6 ; 978-3-433-60335-2 ; 978-3-433-60508-0 ; 3-433-60508-4}, pages = {37 -- 62}, year = {2014}, language = {de} } @article{BungErpicumTullis2020, author = {Bung, Daniel Bernhard and Erpicum, S{\´e}bastien and Tullis, Blanke P.}, title = {Advances in hydraulic structures engineering}, series = {Journal of Hydraulic Engineering}, volume = {147}, journal = {Journal of Hydraulic Engineering}, number = {1}, publisher = {ASCE}, address = {Reston, Va.}, issn = {0733-9429 (Druckausgabe)}, doi = {10.1061/(ASCE)HY.1943-7900.0001851}, pages = {1 Seite}, year = {2020}, language = {en} } @inproceedings{BungValeroHermens2018, author = {Bung, Daniel B. and Valero, Daniel and Hermens, G.}, title = {Hybrid investigation on the hydraulic performance of a new trapezoidal fishway}, series = {7th IAHR International Symposium on Hydraulic Structures, ISHS 2018}, booktitle = {7th IAHR International Symposium on Hydraulic Structures, ISHS 2018}, isbn = {978-069213277-7}, doi = {10.15142/T3S06R}, pages = {184 -- 193}, year = {2018}, language = {de} } @inproceedings{BungValero2015, author = {Bung, Daniel B. and Valero, Daniel}, title = {Image processing for bubble image velocimetry in self-aerated flows}, series = {E-proceedings of the 36th IAHR World Congress 28 June - 3 July, 2015, The Hague, the Netherlands}, booktitle = {E-proceedings of the 36th IAHR World Congress 28 June - 3 July, 2015, The Hague, the Netherlands}, organization = {IAHR World Congress <36, 2015, Den Haag>}, pages = {1 -- 8}, year = {2015}, language = {en} } @inproceedings{BungValero2016, author = {Bung, Daniel B. and Valero, Daniel}, title = {Application of the optical flow method to velocity determination in hydraulic structure models}, series = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016}, booktitle = {Hydraulic Structures and Water System Management. 6th IAHR International Symposium on Hydraulic Structures, Portland, OR, 27-30 June 2016}, editor = {Crookston, B. and Tullis, B.}, isbn = {978-1-884575-75-4}, doi = {10.15142/T3150628160853}, pages = {223 -- 232}, year = {2016}, language = {en} } @inproceedings{BungValero2016, author = {Bung, Daniel B. and Valero, Daniel}, title = {Image processing techniques for velocity estimation in highly aerated flows: bubble image velocimetry vs. optical flow}, series = {Sustainable Hydraulics in the Era of Global Change : Proceedings of the 4th IAHR Europe Congress (Liege, Belgium, 27-29 July 2016)}, booktitle = {Sustainable Hydraulics in the Era of Global Change : Proceedings of the 4th IAHR Europe Congress (Liege, Belgium, 27-29 July 2016)}, editor = {Dewals, Benjamin}, publisher = {CRC Press}, isbn = {978-1-138-02977-4}, doi = {10.1201/b21902-31}, pages = {151 -- 157}, year = {2016}, language = {en} } @inproceedings{BungValero2017, author = {Bung, Daniel B. and Valero, Daniel}, title = {FlowCV - An open-source toolbox for computer vision applications in turbulent flows}, series = {Proceedings of the 37th IAHR World Congress August 13 - 18, 2017, Kuala Lumpur, Malaysia}, booktitle = {Proceedings of the 37th IAHR World Congress August 13 - 18, 2017, Kuala Lumpur, Malaysia}, issn = {2521-716X}, pages = {5356 -- 5365}, year = {2017}, language = {en} } @article{BungValero2018, author = {Bung, Daniel B. and Valero, Daniel}, title = {Re-aeration on stepped spillways with special consideration of entrained and entrapped air}, series = {Geosciences}, volume = {8}, journal = {Geosciences}, number = {9}, publisher = {MDPI}, address = {Basel}, issn = {2076-3263}, pages = {Article number 333}, year = {2018}, abstract = {As with most high-velocity free-surface flows, stepped spillway flows become self-aerated when the drop height exceeds a critical value. Due to the step-induced macro-roughness, the flow field becomes more turbulent than on a similar smooth-invert chute. For this reason, cascades are oftentimes used as re-aeration structures in wastewater treatment. However, for stepped spillways as flood release structures downstream of deoxygenated reservoirs, gas transfer is also of crucial significance to meet ecological requirements. Prediction of mass transfer velocities becomes challenging, as the flow regime differs from typical previously studied flow conditions. In this paper, detailed air-water flow measurements are conducted on stepped spillway models with different geometry, with the aim to estimate the specific air-water interface. Re-aeration performances are determined by applying the absorption method. In contrast to earlier studies, the aerated water body is considered a continuous mixture up to a level where 75\% air concentration is reached. Above this level, a homogenous surface wave field is considered, which is found to significantly affect the total air-water interface available for mass transfer. Geometrical characteristics of these surface waves are obtained from high-speed camera investigations. The results show that both the mean air concentration and the mean flow velocity have influence on the mass transfer. Finally, an empirical relationship for the mass transfer on stepped spillway models is proposed.}, language = {en} } @article{BungValero2016, author = {Bung, Daniel B. and Valero, Daniel}, title = {Optical flow estimation in aerated flows}, series = {Journal of Hydraulic Research}, volume = {54}, journal = {Journal of Hydraulic Research}, number = {5}, publisher = {Taylor \& Francis}, address = {London}, doi = {10.1080/00221686.2016.1173600}, pages = {575 -- 580}, year = {2016}, abstract = {Optical flow estimation is known from Computer Vision where it is used to determine obstacle movements through a sequence of images following an assumption of brightness conservation. This paper presents the first study on application of the optical flow method to aerated stepped spillway flows. For this purpose, the flow is captured with a high-speed camera and illuminated with a synchronized LED light source. The flow velocities, obtained using a basic Horn-Schunck method for estimation of the optical flow coupled with an image pyramid multi-resolution approach for image filtering, compare well with data from intrusive conductivity probe measurements. Application of the Horn-Schunck method yields densely populated flow field data sets with velocity information for every pixel. It is found that the image pyramid approach has the most significant effect on the accuracy compared to other image processing techniques. However, the final results show some dependency on the pixel intensity distribution, with better accuracy found for grey values between 100 and 150.}, language = {en} } @inproceedings{BungTullis2018, author = {Bung, Daniel B. and Tullis, Blake}, title = {Hydraulic Structures - ISHS2018 in Perspective}, series = {7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May}, booktitle = {7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May}, isbn = {978-0-692-13277-7}, doi = {10.15142/T3WH2B}, pages = {9 seiten}, year = {2018}, language = {en} } @inproceedings{BungSunMeirelesetal.2012, author = {Bung, Daniel B. and Sun, Q. and Meireles, I. and Matos, J. and Viseu, T.}, title = {USBR type III stilling basin performance for steep stepped spillways}, series = {Hydraulic structures into the 21st century : 4th IAHR International Symposium on Hydraulic Structures : 9.-11.2.2012, Porto}, booktitle = {Hydraulic structures into the 21st century : 4th IAHR International Symposium on Hydraulic Structures : 9.-11.2.2012, Porto}, organization = {International Symposium on Hydraulic Structures <4, 2012, Porto>}, isbn = {978-989-8509-01-7}, pages = {Elektronisch publiziert}, year = {2012}, language = {en} } @inproceedings{BungSchlenkhoffOertel2009, author = {Bung, Daniel B. and Schlenkhoff, Andreas and Oertel, M.}, title = {Self-aerated skimming flow on embankment stepped spillways}, series = {Water engineering for sustainable environment : 33rd IAHR congress ; 9 - 14 August 2009, Vancouver, British Columbia, Canada}, booktitle = {Water engineering for sustainable environment : 33rd IAHR congress ; 9 - 14 August 2009, Vancouver, British Columbia, Canada}, organization = {International Association for Hydraulic Engineering and Research}, isbn = {9789078046080}, pages = {1 CD-ROM}, year = {2009}, language = {en} } @inproceedings{BungSchlenkhoff2010, author = {Bung, Daniel B. and Schlenkhoff, Andreas}, title = {Self-aerated skimming flow on embankment stepped spillways : the effect of additional micro-roughness on energy dissipation and oxygen transfer}, series = {Proceedings from first IAHR European congress : May 2010, Edinburgh}, booktitle = {Proceedings from first IAHR European congress : May 2010, Edinburgh}, publisher = {Heriot-Watt University, School of the Built Environment}, address = {Edinburgh}, organization = {International Association for Hydraulic Engineering and Research}, isbn = {9780956595102}, pages = {Artikelkennnummer HSIIId}, year = {2010}, language = {en} } @inproceedings{BungSchlenkhoff2010, author = {Bung, Daniel B. and Schlenkhoff, Andreas}, title = {Selbstbel{\"u}ftete Gerinnestr{\"o}mungen auf Treppenschussrinnen}, series = {Talsperren im Wandel : 15. Deutsches Talsperrensymposium ; Beitr{\"a}ge zur Tagung am 14. bis 16. April 2010 im Eurogress Aachen}, booktitle = {Talsperren im Wandel : 15. Deutsches Talsperrensymposium ; Beitr{\"a}ge zur Tagung am 14. bis 16. April 2010 im Eurogress Aachen}, organization = {Deutsches TalsperrenKomitee}, isbn = {978-3-8322-9043-6}, pages = {39 -- 47}, year = {2010}, language = {de} }