• Achieving nitritation and anammox enrichment in a single moving-bed biofilm reactor treating reject waterZekker, Ivar; Rikmann, Ergo; Tenno, Taavo; Saluste, Anne; Tomingas, Martin; Menert, Anne; Loorits, Liis; Lemmiksoo, Vallo; Tenno, ToomasEnvironmental technology2012 / p. 703-710 : ill https://pubmed.ncbi.nlm.nih.gov/22629646/
• Achieving nitritation and anammox enrichment in single moving bed biofilm reactor treating reject waterZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Saluste, Anne; Lemmiksoo, Vallo; Menert, Anne; Loorits, Liis; Tenno, TaavoAGRO 2011 : 8th IWA International Symposium on Waste Management Problems in Agroindustries : Cesme, Izmir, Turkey, 22-24 June 2011 : proceedings. 22011 / p. 827-828 https://www.tandfonline.com/doi/full/10.1080/09593330.2011.588962
• Aktiivsöe valmistamise võimalused biomudastPikkov, Lui; Kallas, Juha; Rikmann, ErgoXXIII Eesti keemiapäevad : teaduskonverentsi ettekannete referaadid1997 / lk. 107
• Ameliorating effect of nitrate on nitrite inhibition for denitrifying P-accumulating organismsZekker, Ivar; Mandel, Anni; Rikmann, Ergo; Jaagura, Madis; Salmar, Siim; Ghangrekar, Makarand Madhao; Tenno, TaavoScience of the total environment2021 / art. 149133, 10 p. : ill https://doi.org/10.1016/j.scitotenv.2021.149133 https://www.scopus.com/sourceid/25349 https://www.scopus.com/record/display.uri?eid=2-s2.0-85111007431&origin=inward&txGid=562dcb34a637ae9a84f5fbe24dddf32b https://jcr.clarivate.com/jcr-jp/journal-profile?journal=SCI%20TOTAL%20ENVIRON&year=2022 https://www.webofscience.com/wos/woscc/full-record/WOS:000704390200018
• An investigation and microcalorimetric monitoring of anaerobic treatment of concentrated waste in the cheese industryBlonskaja, Viktoria; Mölder, Heino; Menert, Anne; Rikmann, Ergo; Vilu, RaivoEuropean water management2001 / 1, p. 59-64 : ill
• An investigation and microcalorimetric monitoring of anaerobic treatment of concentrated waste in the cheese industryBlonskaja, Viktoria; Mölder, Heino; Menert, Anne; Rikmann, Ergo; Vilu, RaivoCopenhagen Waste and Water Conference '99 including EcoProcura Copenhagen '99 : The 2nd International Conference on Integrated Sustainable Waste and Water Management and Green Procurement : June 1-3, 1999 : conference proceedings1999 / [3] p https://www.researchgate.net/publication/224858929_An_investigation_and_microcalorimetric_monitoring_of_anaerobic_treatment_of_concentrated_waste_in_the_cheese_industry
• Anaerobic ammonium oxidation process performance with optimum bicarbonate concentrationZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Menert, Anne; Tomingas, Martin; Kroon, K.; Vabamäe, Priit; Tenno, TaavoAgricultural research : abstract book from the 4th Annual International Symposium on Agricultural Research : 18-21 July 2011, Athens, Greece2011 / p. 69-71 : ill
• Anaerobic mesophilic digestion of sludge with extra-thermophilic and high pH pre-treatmentMenert, Anne; Rikmann, Ergo; Michelis, Merje; Vaalu, Tarmo; Blonskaja, Viktoria; Vilu, Raivo4th Conference on the Establishment of Cooperation between Companies and Institutions in the Baltic Sea Region (Kalmar Eco-Tech'03) : 25-27 November, 2003, Kalmar, Sweden : book of abstracts2003 / p. 115 https://open.lnu.se/index.php/eco-tech/article/view/2102
• Anaerobic mesophilic digestion of sludge with extra-thermophilic and high pH pre-treatmentMenert, Anne; Rikmann, Ergo; Michelis, Merje; Vaalu, Tarmo; Blonskaja, Viktoria; Vilu, RaivoProceedings of 4th Conference on the Establishment of Cooperation between Companies and Institutions in the Baltic Sea Region2005 / p. 451-463 https://open.lnu.se/index.php/eco-tech/article/view/2102
• Anaeroobse ammoniumlämmastiku oksüdatsiooni protsessi kiirendamine NH2OH ja N2H4-gaZekker, Ivar; Kroon, K.; Rikmann, Ergo; Tenno, Toomas; Menert, Anne; Tenno, TaavoXXXII Eesti Keemiapäevad : teaduskonverentsi teesid2011 / lk. 114 https://www.ester.ee/record=b2679915*est
• Analysis of extracellular polymeric substances from pre-treated sludge by high-performance size exclusion chromatographyLepane, Viia; Menert, Anne; Michelis, Merje; Rikmann, Ergo; Vilu, RaivoInternational Symposium Analytical Forum 2004 : Warsaw, Poland : Book of abstracts2004 / p. 202
• Anammox bacteria enrichment and phylogenic analysis in moving bed biofilm reactorsZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Vabamäe, Priit; Tomingas, Martin; Menert, Anne; Loorits, Liis; Tenno, TaavoEnvironmental engineering science2012 / p. 946-950 https://www.liebertpub.com/doi/abs/10.1089/ees.2011.0146?journalCode=ees
• Anammox enrichment from reject water on blank biofilm carriers and carriers containing nitrifying biomass : operation of two moving bed biofilm reactors (MBBR)Zekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Lemmiksoo, Vallo; Menert, Anne; Loorits, Liis; Vabamäe, Priit; Tomingas, Martin; Tenno, TaavoBiodegradation2012 / p. 547-560 : ill https://www.researchgate.net/publication/221811952_Anammox_enrichment_from_reject_water_on_blank_biofilm_carriers_and_carriers_containing_nitrifying_biomass_Operation_of_two_moving_bed_biofilm_reactors_MBBR
• ANAMMOX-denitrification biomass in microbial fuel cell to enhance the electricity generation and nitrogen removal efficiencyZekker, Ivar; Bhowmick, Gourav Dhar; Priks, Hans; Nath, Dibyojyoty; Rikmann, Ergo; Jaagura, MadisBiodegradation2020 / p. 249 - 264 https://doi.org/10.1007/s10532-020-09907-w https://www.scopus.com/sourceid/25711 https://www.scopus.com/record/display.uri?eid=2-s2.0-85090239460&origin=resultslist&sort=plf-f&src=s&sid=282cf92df19dc9d416175779c2268c99&sot=b&sdt=b&s=DOI%2810.1007%2Fs10532-020-09907-w%29&sl=26&sessionSearchId=282cf92df19dc9d416175779c2268c99&relpos=0 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=BIODEGRADATION&year=2022 https://www.webofscience.com/wos/woscc/full-record/WOS:000565847800001
• Biolagunevate jäätmete fermentatsioon taastuvate energiaallikate saamiseksMenert, Anne; Michelis, Merje; Rikmann, Ergo; Blonskaja, Viktoria; Kaljurand, Mihkel; Kallaste, TiitTEUK XII : taastuvate energiaallikate uurimine ja kasutamine : kaheteistkümnenda konverentsi kogumik2010 / lk. 49-59 : ill
• Biological treatment of anaerobic digester supernatant by anaerobic ammonium oxidation method in UASB systemTomingas, Martin; Zekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Menert, Anne; Kroon, Kristel; Tenno, TaavoSustainChem2011 : International Conference on Materials and Technologies for Green Chemistry jointly with Workshop of COST Action CM0903 (UBIOCHEM-II) : September 5-9, 2011, Tallinn, Estonia : abstract book and program2011 / p. 140
• Characteristics of activated carbon produced from biosludge and its use in wastewater post-treatmentPikkov, Lui; Kallas, Juha; Rüütmann, Tiia; Rikmann, ErgoEnvironmental technology2001 / p. 229-236 : ill
• Comparison of sulfate-reducing and conventional Anammox upflow anaerobic sludge blanket reactorsRikmann, Ergo; Zekker, Ivar; Tomingas, Martin; Vabamäe, Priit; Kroon, Kristel; Saluste, Alar; Tenno, Taavo; Menert, Anne; Rubin, Sergio S.C.Journal of bioscience and bioengineering2014 / p. 426-433 : ill https://doi.org/10.1016/j.jbiosc.2014.03.012 https://www.scopus.com/sourceid/16337 https://www.scopus.com/record/display.uri?eid=2-s2.0-84921673509&origin=inward&txGid=bebddd189bba956fffbf3c2d0cc45ddd https://jcr.clarivate.com/jcr-jp/journal-profile?journal=J%20BIOSCI%20BIOENG&year=2014 https://www.webofscience.com/wos/woscc/full-record/WOS:000345189300012
• Deammonification process start-up after enrichment of anammox microorganisms from reject water in a moving-bed biofilm reactorZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Kroon, Kristel; Vabamäe, Priit; Salo, Erik; Tenno, Taavo; Loorits, Liis; Dc Rubin, Sergio S. C.; Vlaeminck, Siegfried E.Environmental Technology (United Kingdom)2013 / p. 3095 - 3101 https://doi.org/10.1080/09593330.2013.803134 https://www.scopus.com/sourceid/21552 https://www.scopus.com/record/display.uri?eid=2-s2.0-84883022377&origin=resultslist&sort=plf-f&src=s&sot=b&sdt=b&s=DOI%2810.1080%2F09593330.2013.803134%29&sessionSearchId=2578bba73f583d2598e5d9854114f0a3 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=ENVIRON%20TECHNOL&year=2013 https://www.webofscience.com/wos/woscc/full-record/WOS:000332322200006
• Effect of bicarbonate concentration on Anaerobic ammonium oxidation for efficient autotrophic nitrogen removalZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Menert, Anne; Lemmiksoo, Vallo; Kolberg, K.; Tenno, TaavoIWA Specialist Conference Water and Industry : Valladolid, Spain, 1-4 May 2011 : final program2011 / p. 16
• Enhanced efficiency of nitritating-anammox sequencing batch reactor achieved at low decrease rates of oxidation-reduction potentialZekker, Ivar; Kivirüüt, Aimar; Rikmann, Ergo; Mandel, Anni; Jaagura, Madis; Tenno, Toomas; Artemchuk, Oleg; Rubin, Sergio Dc; Tenno, TaavoEnvironmental Engineering Science2019 / p. 350-360 https://doi.org/10.1089/ees.2018.0225 https://www.scopus.com/sourceid/25749 https://www.scopus.com/record/display.uri?eid=2-s2.0-85063083231&origin=resultslist&sort=plf-f&src=s&sid=199ce1b428b9e0b4058818bf89480d7c&sot=b&sdt=b&s=TITLE-ABS-KEY%28%22achieved+at+low+decrease%22%29&sl=41&sessionSearchId=199ce1b428b9e0b4058818bf89480d7c&relpos=0 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=ENVIRON%20ENG%20SCI&year=2022 https://www.webofscience.com/wos/woscc/full-record/WOS:000452611000001
• Influence of thermal pre-treatment on mesophilic anaerobic digestion of sludgesMenert, Anne; Vaalu, Tarmo; Michelis, Merje; Blonskaja, Viktoria; Rikmann, Ergo; Mets, Aita; Vilu, RaivoThe 7th International Conference : Environmental Engineering : May 22-23, 2008, Vilnius, Lithuania : selected papers. Volume II, Water engineering. Energy for buildings2008 / p. 625-635 : ill
• Mainstream-sidestream wastewater switching promotes anammox nitrogen removal rate in organic-rich, low-temperature streamsZekker, Ivar; Raudkivi, Markus; Artemchuk, Oleg; Rikmann, Ergo; Priks, Hans; Jaagura, Madis; Tenno, TaavoEnvironmental technology2021 / 10 p. : ill https://doi.org/10.1080/09593330.2020.1721566 https://www.scopus.com/sourceid/21552 https://www.scopus.com/record/display.uri?eid=2-s2.0-85079238667&origin=inward&txGid=6c0c6294d887f82dbb71cb4df3ed3150 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=ENVIRON%20TECHNOL&year=2022 https://www.webofscience.com/wos/woscc/full-record/WOS:000513364700001
• Modification of nitrifying biofilm into nitritating one by combination of increased free ammonia concentrations, lowered HRT and dissolved oxygen concentrationZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Menert, Anne; Lemmiksoo, Vallo; Saluste, Anne; Tenno, Taavo; Tomingas, MartinJournal of environmental sciences2011 / p. 1113-1121 : ill https://www.sciencedirect.com/science/article/pii/S1001074210605232
• Nitric oxide for anammox recovery in a nitrite-inhibited deammonification systemZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Loorits, Liis; Kroon, Kristel; Fritze, Hannu; Tuomivirta, Tero; Vabamäe, Priit; Raudkivi, Markus; Mandel, Anni; Rubin, Sergio S.C.; Tenno, TaavoEnvironmental Technology (United Kingdom)2015 / p. 2477 - 2487 https://doi.org/10.1080/09593330.2015.1034791
• Nitritating-anammox biomass tolerant to high dissolved oxygen concentration and C/N ratio in treatment of yeast factory wastewaterZekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Seiman, Andrus; Loorits, LiisEnvironmental technology2014 / p. 1565-1576 : ill https://doi.org/10.1080/09593330.2013.874492 https://www.scopus.com/sourceid/21552 https://www.scopus.com/record/display.uri?eid=2-s2.0-84894283296&origin=inward&txGid=383dd1574f3c7a429c443c043e5c7451 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=ENVIRON%20TECHNOL&year=2014 https://www.webofscience.com/wos/woscc/full-record/WOS:000331357100015
• Possibilities of production of active carbon from biological sludgePikkov, Lui; Kallas, Juha; Rikmann, Ergo23rd Estonian Chemistry Days : abstracts of scientific conference1997 / p. 117
• Recycling bitumen for composite material production : Potential applications in the construction sectorRikmann, Ergo; Mäeorg, Uno; Vaino, Neeme; Pallav, Vello; Järvik, Oliver; Liiv, JüriApplied Sciences (Switzerland)2025 / art. 1313 https://doi.org/10.3390/app15031313
• Research of specific nitrite oxidation rate on high surfaced biofilms carriers with free ammonia and temperature variationsZekker, Ivar; Tenno, Toomas; Tenno, Taavo; Lemmiksoo, Vallo; Rikmann, Ergo; Menert, Anne; Kolberg, K.3rd EuCheMS Chemistry Congress : Chemistry - the Creative Force : 29.08.-02.09.2010, Nürnberg, Germany : [abstracts]2010 / [1] p https://www.etis.ee/Portal/Publications/Display/e183db0e-18fc-43e3-9bab-bdc76c638e92
• Specific nitrite oxidation rate on high surfaced biofilm carriers dependent on free ammonia and temperatureZekker, Ivar; Tenno, Toomas; Tenno, Taavo; Lemmiksoo, Vallo; Rikmann, Ergo; Menert, Anne; Kolberg, K.; Tomingas, Martin; Kroon, K.; Vabamäe, Priit2nd Workshop on Bacterial and Fungal Biofilms : Ghent University Center for Sociomicrobiology, 22 September 20112011 https://www.etis.ee/Portal/Publications/Display/33df8771-46e4-46c6-a2da-dbd4efb91a17
• Start-up of low-temperature anammox in UASB from mesophilic yeast factory anaerobic tank inoculumZekker, Ivar; Rikmann, Ergo; Seiman, Andrus; Loorits, LiisEnvironmental technology2015 / p. 214-225 : ill
• Step-wise temperature decreasing cultivates a biofilm with high nitrogen removal rates at 9°C in short-term anammox biofilm testsZekker, Ivar; Rikmann, Ergo; Mandel, Anni; Kroon, Kristel; Seiman, Andrus; Mihkelson, Jana; Tenno, Taavo; Tenno, ToomasEnvironmental technology2016 / p. 1933 - 1946 https://doi.org/10.1080/09593330.2015.1135995 https://www.scopus.com/sourceid/21552 https://www.scopus.com/record/display.uri?eid=2-s2.0-84958533010&origin=resultslist&sort=plf-f&src=s&sid=36ceddf0345397a3192e81e230848760&sot=b&sdt=b&s=DOI%2810.1080%2F09593330.2015.1135995%29&sl=34&sessionSearchId=36ceddf0345397a3192e81e230848760&relpos=0 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=ENVIRON%20TECHNOL&year=2016 https://www.webofscience.com/wos/woscc/full-record/WOS:000375950700009
• Sulfate-dependent anaerobic ammonium oxidation in baker's yeast wastewaterRikmann, Ergo; Menert, Anne; Blonskaja, Viktoria; Kurissoo, Tõnu; Zub, Sergei; Tenno, ToomasBook of abstracts of the 7th International Conference ORBIT 2010 : Organic Resources in the Carbon Economy : 29th June to 3rd July 2010 Heraklion Crete, Greece2010 / p. 204 https://www.sei.org/publications/sulfate-dependent-anaerobic-ammonium-oxidation-bakers-yeast-wastewater/
• Sulfate-reducing anaerobic ammonium oxidation as a potential treatment method for high nitrogen-content wastewaterRikmann, Ergo; Zekker, Ivar; Tomingas, Martin; Tenno, Toomas; Menert, Anne; Loorits, Liis; Tenno, TaavoAGRO 2011 : 8th IWA International Symposium on Waste Management Problems in Agroindustries : Cesme, Izmir, Turkey, 22-24 June 2011 : proceedings. 22011 / p. 755-762 https://www.researchgate.net/publication/348845233_Sulfate-reducing_anaerobic_ammonium_oxidation_as_a_potential_treatment_method_for_high_nitrogen-content_wastewater
• Sulfate-reducing anaerobic ammonium oxidation as a potential treatment method for high nitrogen-content wastewaterRikmann, Ergo; Zekker, Ivar; Tomingas, Martin; Tenno, Taavo; Menert, Anne; Loorits, Liis; Tenno, ToomasBiodegradation2012 / p. 509-524 : ill https://www.researchgate.net/publication/348845233_Sulfate-reducing_anaerobic_ammonium_oxidation_as_a_potential_treatment_method_for_high_nitrogen-content_wastewater
• Sulfate-reducing anammox for sulfate and nitrogen containing wastewatersRikmann, Ergo; Zekker, Ivar; Tomingas, Martin; Tenno, Toomas; Loorits, Liis; Vabamäe, Priit; Mandel, Anni; Raudkivi, Markus; Daija, Laura; Kroon, Kristel; Tenno, TaavoDesalination and Water Treatment2016 / p. 3132 - 3141 https://doi.org/10.1080/19443994.2014.984339 https://www.scopus.com/sourceid/19700175585 https://www.scopus.com/record/display.uri?eid=2-s2.0-84953838922&origin=resultslist&sort=plf-f&src=s&sid=36ceddf0345397a3192e81e230848760&sot=b&sdt=b&s=DOI%2810.1080%2F19443994.2014.984339%29&sl=34&sessionSearchId=36ceddf0345397a3192e81e230848760&relpos=0 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=DESALIN%20WATER%20TREAT&year=2016 https://www.webofscience.com/wos/woscc/full-record/WOS:000367838000027