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Microbial and chemical quality assessment of the small rivers entering the South Baltic. Part II: Case study on the watercourses in the Puck Bay catchment area
PublikacjaDue to its location, Puck Bay is an area particularly vulnerable to pollution of anthropogenic origin. The aim of the study was to assess the water quality of small watercourses entering the inner part of Puck Bay. The paper presents the results of chemical and microbiological analyses of 10 rivers and canals at their estuaries located on the western shore of the internal Puck Bay. The following environmental parameters were analyzed:...
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The effects of different aeration modes on ammonia removal from sludge digester liquors in the nitritation–anammox proces
PublikacjaThe aim of this study was to determine the impact of continuous and intermittent aeration on the rate of ammonia removal in the combined nitritation–anammox process. This process was run in two parallel sequencing batch reactors (SBRs), with a working volume V = 10 L, treating sludge digester liquors from the Gdansk (Poland) wastewater treatment plant (WWTP). The ammonia oxidizing bacteria were cultivated from activated sludge...
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Impact of aeration conditions on the removal of low concentrations of nitrogen in a tertiary partially aerated biological filter
PublikacjaA submerged biological aerated filter (BAF) partially aerated was used to study the removal of low concentrations of ammonia nitrogen (0.3 g N/m3 to 30.5 g N/m3) typically found in nutrient enriched river and lake waters, and treated effluents. Four series of experiments were performed with a synthetic wastewater at ammonia loading rates between 6 g N/m3 d and 903 g N/m3 d and C/N ratios from 2 to 20. The results showed that ammonia...
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Strategies for mitigating nitrous oxide production and decreasing the carbon footprint of a full-scale combined nitrogen and phosphorus removal activated sludge system
PublikacjaNitrous oxide (N2O) emitted from biological nutrient removal activated sludge systems contributes significantly to the total carbon footprint of modern wastewater treatment plants. In the present study, N2O production and emissions were experimentally determined in a large-scale plant (220,000 PE) employing combined nitrogen (N) and phosphorus (P) removal. As a modelling tool, the Activated Sludge Model 2d (ASM2d) was extended...
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An overview of the strategies for the deammonification process start-up and recovery after accidental operational failures
PublikacjaThe deammonification process has been universally acknowledged as an energy-efficient technology for sewage disposal. In contrast with traditional biological nitrogen removal technology, the deammonification process is able to remove ammonia from wastewater with the simplest nitrogen removal process because of its advantages of lower operating expenses, no organic carbon consumption, lower biomass production, lower carbon dioxide...
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Automotive fleet repair facility wastewater treatment using air/ZVI and air/ZVI/H2 O2 processes
PublikacjaAdvanced automotive fl eet repair facility wastewater treatment was investigated with Zero-Valent Iron/Hydrogen Peroxide (Air/ZVI/H2 O2 ) process for different process parameters: ZVI and H2 O2 doses, time, pH. The highest Chemical Oxygen Demand (COD) removal effi ciency, 76%, was achieved for ZVI/H2 O2 doses 4000/1900 mg/L, 120 min process time, pH 3.0. COD decreased from 933 to 227 mg/L. In optimal process conditions odor and...
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Optimization of the Aeration Strategies in a Deammonification Sequencing Batch Reactor for Efficient Nitrogen Removal and Mitigation of N2O Production
PublikacjaIn deammonification systems, nitrite-oxidizing bacteria (NOB) suppression and nitrous oxide (N2O) mitigation are two important operational objectives. To carry out this multivariable analysis of response, a comprehensive model for the N cycle was developed and evaluated against experimental data from a laboratory-scale deammonification granular sludge sequencing batch reactor. Different aeration strategies were tested, and the manipulated...
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Denitrifcation rate in the mainstream deammonification
PublikacjaThe conventional processes of biological nitrogen removal based on nitrification and denitrification does not fit properly into the concept of the circular economy. As the alternative one should consider the deammonification process, which is a combination of partial nitrification (nitritation) and Anammox processes. It consists of removing ammonium nitrogen from wastewater under anaerobic conditions by a group of autotrophic microorganisms....
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The coexistence and competition of canonical and comammox nitrite oxidizing bacteria in a nitrifying activated sludge system – Experimental observations and simulation studies
PublikacjaThe second step of nitrification can be mediated by nitrite oxidizing bacteria (NOB), i.e. Nitrospira and Nitrobacter, with different characteristics in terms of the r/K theory. In this study, an activated sludge model was developed to account for competition between two groups of canonical NOB and comammox bacteria. Heterotrophic denitrification on soluble microbial products was also incorporated into the model. Four 5-week washout...
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Comparison of the Efficiency of Deammonification under Different DO Concentrations in a Laboratory-Scale Sequencing Batch Reactor
PublikacjaThe efficiency of deammonification depends on the cooperation of ammonium oxidizing bacteria and archaea (AOB/AOA), anaerobic ammonium oxidizing bacteria (AnAOB) and the effective suppression of nitrite oxidizing bacteria (NOB) that compete with AnAOB for nitrite (NO2 -N). One of the effective NOB suppression strategies is intermittent aeration. However, it is important to have a good understanding of the optimum dissolved oxygen...
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Combined partial denitrification/anammox process for nitrogen removal in wastewater treatment
PublikacjaRecently, the combined partial denitrification and anammox (PD/anammox) has received special attention as a viable alternative for N removal using organic matter present in municipal wastewater. In comparison with conventional nitrification-denitrification, PD/anammox provides enormous opportunities to achieve sustainable wastewater treatment due to the lack of dissolved oxygen (DO) demand, a smaller amount of organic carbon (C)...
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The advanced monitoring as a key factor for appropriate optimization and control of full-scale activated sludge systems – case study Debogorze WWTP.
PublikacjaComputer simulation has become a helpful tool in wastewater treatment systems performance and effectiveness analysis. Advanced monitoring, by using appropriate software, enables to create a mathematical model of a real wastewater treatment plant (WWTP), run a simulation and subsequently interpret results under various conditions. An operation of WWTP is usually controlled by global parameters such as flow, solids retention time,...
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Improving the energy balance in wastewater treatment plants by optimization of aeration control and application of new technologies
PublikacjaThe methods to improve the energy balance of a wastewater treatment plant (WWTP) by optimization of aeration process control and application of innovative nitrogen removal technologies were overviewed in the study. The control of aeration based on the ABAC (Ammonia-Based Aeration Control) system allows not only for significant savings in electricity consumption, but it can also increase the efficiency of the denitrification process....
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Seasonal changes of mercury speciation in the coastal sediments
PublikacjaPurpose Mercury speciation in sediments is linked to environmental conditions and processes. Domination of particular mercury species depends on its source, displays considerable seasonal behavior, and may be further modified due to oxygen levels, icing conditions, or the input of fresh organic matter. The purpose of this study was to examine the coastal area of the Gulf of Gdańsk in terms of mercury contamination and the influence...
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Optymalizacja procesów biologicznych w oczyszczalni ścieków typu SBR
Publikacjaiologiczna oczyszczalnia ścieków jest skomplikowanym systemem sterowania. Jednym z istotnych i kosztownych procesów tam zachodzących jest napowietrzanie ścieków. Prawidłowy jego przebieg ma decydujący wpływ na stopień oczyszczenia ścieków i koszty operacyjne pracy oczyszczalni. W związku z tym prowadzone są prace badawcze nad optymalizacją procesów biologicznych, pozwalającą redukować koszty, np. zużycie energii. W artykule opracowano...