- document
-
Toja Ortega, S. (author), Pronk, M. (author), de Kreuk, M.K. (author)High concentrations of particulate COD (pCOD) in the influent of aerobic granular sludge (AGS) systems are often associated to small granule diameter and a large fraction of flocculent sludge. At high particulate concentrations even granule stability and process performance might be compromised. However, pilot-or full-scale studies focusing...journal article 2021
- document
-
Wei, P. (author), Uijttewaal, W.S.J. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)Accurate rheological characterisation of sewage waste activated sludge (WAS) is of high importance for downstream processing related to optimised sludge pumping and mixing, assessment of energy demands and overall process design. However, to elaborate rheological behaviour is often challenging under dynamic operational conditions in practice....journal article 2021
- document
-
Toja Ortega, S. (author), Pronk, M. (author), de Kreuk, M.K. (author)Complex substrates, like proteins, carbohydrates, and lipids, are major components of domestic wastewater, and yet their degradation in biofilm-based wastewater treatment technologies, such as aerobic granular sludge (AGS), is not well understood. Hydrolysis is considered the rate-limiting step in the bioconversion of complex substrates, and as...journal article 2021
- document
-
van den Berg, L. (author), Kirkland, Catherine M. (author), Seymour, Joseph D. (author), Codd, Sarah L. (author), van Loosdrecht, Mark C.M. (author), de Kreuk, M.K. (author)Aerobic granular sludge (AGS) technology allows simultaneous nitrogen, phosphorus, and carbon removal in compact wastewater treatment processes. To operate, design, and model AGS reactors, it is essential to properly understand the diffusive transport within the granules. In this study, diffusive mass transfer within full-scale and lab-scale...journal article 2020
- document
-
Kooijman, G. (author), de Kreuk, M.K. (author), Houtman, C. (author), van Lier, J.B. (author)Literature frequently reports that colloids in aqueous matrices sorb a large fraction of pharmaceuticals. Since coagulation/flocculation removes colloids, it is expected that coagulation/flocculation in principle should be useful in concentrating pharmaceuticals in wastewater treatment, which would facilitate the treatment of these refractory...journal article 2020
- document
-
Guo, H. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)Full-scale aerobic granular sludge technology under the trade name Nereda® has been implemented for municipal, as well as industrial wastewater treatment. Owing to the operational reactor procedures, two types of waste aerobic granular sludge can be clearly distinguished: 1) aerobic granular sludge selection discharge (AGS-SD) and 2) aerobic...journal article 2020
- document
-
Guo, H. (author), Felz, S. (author), Lin, Y. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)Aerobic granular sludge (AGS) technology is an alternative to conventional activated sludge to reduce the process footprint and energy consumption. Strategies for the efficient management of its produced biomass, that is grown in a granular morphology as well, need further development. Anaerobic digestion (AD) is commonly applied in waste...journal article 2020
- document
-
van den Berg, L. (author), van Loosdrecht, Mark C.M. (author), de Kreuk, M.K. (author)Biofilm and granular sludge processes depend on diffusion of substrates. Despite their importance for the kinetic description of biofilm reactors, biofilm diffusion coefficients reported in literature vary greatly. The aim of this simulation study was to determine to what extent the methods that are used to measure diffusion coefficients...journal article 2020
- document
-
Kirkland, Catherine M. (author), Seymour, Joseph D. (author), Krug, Julia R. (author), Velders, Aldrik H. (author), Vergeldt, Frank J. (author), Van As, Henk (author), van den Berg, L. (author), de Kreuk, M.K. (author), Codd, Sarah L. (author)Despite aerobic granular sludge wastewater treatment plants operating around the world, our understanding of internal granule structure and its relation to treatment efficiency remains limited. This can be attributed in part to the drawbacks of time-consuming, labor-intensive, and invasive microscopy protocols which effectively restrict...journal article 2020
- document
-
de Valk, S.L. (author), Tavares de Sousa, Tales A. (author), Khadem, A.F. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)The objective of this study was to investigate the effect of waste activated sludge (WAS) predation by the aquatic worm Tubifex tubifex (T. tubifex) on the overall biodegradability of WAS. The initial WAS biodegradability potential was determined in 80 days sequential batch-fed anaerobic and aerobic treatment combinations. These treatment...journal article 2020
- document
-
Gonzales, A. (author), Guo, H. (author), Ortega-Ibáñez, Oscar (author), Petri, Coert (author), van Lier, J.B. (author), de Kreuk, M.K. (author), Hendriks, Alexander (author)Sludge pre-treatments are emerging as part of the disposal process of solid by-products of wastewater purification. One of their benefits is the increase in methane production rate and/or yield, along with higher loading capacities of existing digesters. In this study, we report the performance of a pilot-scale compartmentalized digester (volume...journal article 2020
- document
-
Wei, P. (author), Mudde, R.F. (author), Uijttewaal, W.S.J. (author), Spanjers, H. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)This study aimed to characterise the gas-liquid flow and mixing behaviour in a gas-mixed anaerobic digester by improving phase interaction modelling using Computational Fluid Dynamics (CFD). A 2D axisymmetric model validated with experimental data was set up using an Eulerian-Eulerian method. Uncertainty factors, including bubble size, phase...journal article 2019
- document
-
Wei, P. (author), Tan, Qiuman (author), Uijttewaal, W.S.J. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)For a proper operational performance assessment of excess sewage sludge digesters in practice, a better understanding of waste activated sludge (WAS) rheological behaviour is important, especially regarding the low-shear and poor mixing zones in anaerobic digesters. The potential rheological instability of WAS with different total solids (TS)...journal article 2018
- document
-
Gonzales, A. (author), Hendriks, A.T.W.M. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)Pre-treatments for waste activated sludge (WAS) are, in most cases, an attempt to increase the biodegradation and/or improve hydrolysis rate of WAS after anaerobic digestion. This review presents an extensive analysis of WAS pre-treatments effectiveness focusing on increasing the biodegradability. In the first part of the review, WAS is...journal article 2018
- document
-
Hendriks, A.T.W.M. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)Fermentation and anaerobic digestion of organic waste and wastewater is broadly studied and applied. Despite widely available results and data for these processes, comparison of the generated results in literature is difficult. Not only due to the used variety of process conditions, but also because of the many different growth media that are...journal article 2018
- document
-
Peters, M.C.F.M. (author), Keuten, M.G.A. (author), Knezev, Aleksandra (author), van Loosdrecht, Mark C.M. (author), Vrouwenvelder, J.S. (author), Rietveld, L.C. (author), de Kreuk, M.K. (author)Bathers release bacteria in swimming pool water, but little is known about the fate of these bacteria and potential risks they might cause. Therefore, shower water was characterized and subjected to chlorination to identify the more chlorine-resistant bacteria that might survive in a chlorinated swimming pool and therefore could form a...journal article 2018
- document
-
Elucidating the microbial community associated with the protein preference of sludge-degrading wormsde Valk, S.L. (author), Feng, C. (author), Khadem, A.F. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)Sludge predation by aquatic worms results in an increased sludge reduction rate, which is mainly due to the specific removal of a protein fraction from the sludge. As microorganisms play an essential role in sludge hydrolysis a better understanding of the microbial community involved in the worm predation process will provide more insight...journal article 2017
- document
-
Kooijman, G. (author), Lopes, Wilton (author), Zhou, Z. (author), Guo, H. (author), de Kreuk, M.K. (author), Spanjers, H. (author), van Lier, J.B. (author)In this work, we investigated the effects of flocculation aid (FA) addition to an anaerobic dynamic membrane bioreactor (AnDMBR) (7 L, 35°C) treating waste-activated sludge (WAS). The experiment consisted of three distinct periods. In period 1 (day 1–86), the reactor was operated as a conventional anaerobic digester with a solids retention...journal article 2017
- document
-
de Valk, S.L. (author), Khadem, A.F. (author), van Lier, J.B. (author), de Kreuk, M.K. (author)Worm predation (WP) by Tubifex tubifex was investigated using waste activated sludge (WAS) as the substrate. In order to better understand the sludge degradation mechanisms during WP, the activity of five common hydrolytic enzymes was determined and compared among the initial feed activated sludge, endogenous respirated sludge and worm...journal article 2017
- document
-
Peters, M.C.F.M. (author), Keuten, M.G.A. (author), de Kreuk, M.K. (author), Vrouwenvelder, J.S. (author), Rietveld, L.C. (author), Medema, G.J. (author)Aims Most swimming pools use residual disinfectants like chlorine for disinfection. The use of chlorine has several drawbacks: some waterborne-pathogens are chlorine resistant and disinfection by-products (DBPs) may be formed which are associated with various health risks. Therefore, an alternative treatment was developed which consists of...abstract 2017