Due to the difficulty in removing nitrogen from landfill leachate, a combined continuous-flow process of nitritation and anammox was applied to process mature leachate. The transformation rate of ammonia and nitrite accumulation ratio in A/O reactor were kept above 95% and 92% respectively through associated inhibition of free ammonia (FA) and free nitrous acid (FNA) to NOB. The total nitrogen volumetric load of anammox in an UASB reactor was brought up from 0.5kg/(m(3)·d) to 1.2kg/(m(3)·d) by gradually increasing influent substrate concentration and reducing hydraulic retention time (HRT). The results show that COD from mature leachate did not bring obvious inhibition effects to anammox. Under concentrations of influent ammonia and COD which were respectively 1330mg/L and 2250mg/L, the removal efficiencies of TN and COD reached 94% and 62% respectively. In the quantitative PCR reactions, the proportions occupied by AOB, NOB and anammox in A/O were 11.39%, 1.76% and 0.05% respectively; and proportions of those in UASB were 0.35%, 4.01% and 7.78% respectively.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.biortech.2016.04.118 | DOI Listing |
Water Res X
December 2024
School of Energy and Environment, City University of Hong Kong, Hong Kong SAR, China.
The biological nitrogen removal process in wastewater treatment inevitably produces nitrous oxide (NO), a potent greenhouse gas. Coarse bubble mixing is widely employed in wastewater treatment processes to mix anoxic tanks; however, its impacts on NO emissions are rarely reported. This study investigates the effects of coarse bubble mixing on NO emissions in a pilot-scale mainstream nitrite shunt reactor over a 50-day steady-state period.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China.
Microalgae-based wastewater treatment could realize simultaneous nutrients recovery and CO sequestration. However, impacts of environmental microplastics (MPs) and antibiotic co-exposure on microalgal growth, nutrients removal, intracellular nitric oxide (NO) accumulation and subsequent nitrous oxide (NO) emission are unclarified, which could greatly offset the CO sequestration benefit. To reveal the potential impacts of environmental concentrations of MPs and antibiotic co-exposure on microalgal greenhouse gas mitigation, this study investigated the effects of representative MPs (PE, PVC, PA), antibiotic sulfamethoxazole (SMX), and nitrite (NO-N) in various combinations on attached Chlorella sorokiniana growth, nutrients removal, anti-oxidative responses, and NO emission originated from intracellular NO build-up.
View Article and Find Full Text PDFSci Total Environ
January 2025
Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON, Canada. Electronic address:
Upgrading wastewater treatment plants (WWTPs) is a global practice for achieving increasingly stringent nutrient discharge objectives set by governments to accommodate population growth and reduce surface water pollution. However, associated downstream improvements in nutrient conditions are difficult to determine in nearshore regions of large aquatic ecosystems due to complex biophysical processes. We conducted a nine-year water quality study and analyzed the data using linear mixed models (LMMs) within a Before-After-Control-Impact (BACI) framework to assess effects of an upgrade to the Duffin Creek Water Pollution Control Plant (DCWPCP) on surface water nutrient conditions and proliferation of nuisance benthic algae (Cladophora glomerata) in nearshore Lake Ontario.
View Article and Find Full Text PDFJMIR Form Res
January 2025
Hamamatsu University School of Medicine, Hamamatsu City, Chuo-ku, Japan.
Background: One method for noninvasive and simple urinary microalbumin testing is urine test strips. However, when visually assessing urine test strips, accurate assessment may be difficult due to environmental influences-such as lighting color and intensity-and the physical and psychological influences of the assessor. These complicate the formation of an objective assessment.
View Article and Find Full Text PDFWater Res X
May 2025
School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China.
Anaerobic ammonia oxidation (anammox) which converts nitrite and ammonium to dinitrogen gas is an energy-efficient nitrogen removal process. One of the bottlenecks for anammox application in wastewater treatment is the stable supply of nitrite for anammox bacteria. Dissimilatory nitrate reduction to ammonium (DNRA) is a process that converts nitrate to nitrite and then to ammonium.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!