15 The UASB process for wastewater treatment has been extensively studied, but the use of zeolite to improve 16 UASB reactor performance has rarely been explored. In this study, a UASB reactor modified with natural 17 zeolite operating at high nitrogen concentrations (0.5 g/L, 0.7 g/L and 1 g/L) was evaluated. Two laboratory 18 bioreactors, one with zeolite and one without, were operated at amb...

Since the earlier anaerobic treatment systems, the design concepts were improved from classic reactors like septic tanks and anaerobic ponds, to modern high rate reactor configurations like anaerobic filters, UASB, EGSB, fixed film fluidized bed and expanded bed reactors, and others. In this paper, anaerobic reactors are evaluated considering the historical evolution and types of wastewaters. T...

The successful operation of a high-rate anaerobic reactor, up flow anaerobic sludge blanket (UASB) reactor depends on the prevailing physico-chemical and biological conditions during its operation. The wastewater characteristics and composition, the hydrodynamics of the process, and microbial activity are critical for achieving long term, optimal reactor performance. Modeling UASBs can be benef...

This research focuses on performing multiphase solid/liquid/gas CFD simulations of a UASB reactor in order to obtain validated model that provides clearer understanding the hydrodynamic behaviour three phases reactors. Eulerian–Eulerian, laminar, three-dimensional, are carried out using Fluent 16.2. The liquid phase velocity and flow profile through PIV experiments. A mean difference 8.45% is f...

A bench-scale up-flow anaerobic sludge blanket (UASB) reactor was applied to start-up the anaerobic ammonium oxidation (Anammox) process from conventional return activated sludge. The reactor was operated for approximately 170 days and was fed synthetic wastewater containing mainly nitrite ) (NO2 − and ammonium ) (NH 4 + as main substrates. After 106 days of operation, the first evidence of Ana...

Recent research has indicated the advantages of combining anaerobic and aerobic processes for the treatment of municipal wastewater, especially for warm-climate countries. Although this configuration is seen as an economical alternative, is has not been investigated in sufficient detail on a worldwide basis. This work presents the results of the monitoring of a pilot-scale plant comprising of a...

Specific ATP content of volatile solids was measured to characterize the sludge activity in a sequential an-aerobic/aerobic wastewater treatment system, with an upflow anaerobic sludge blanket (UASB) reactor and a three-phase aerobic fluidized bed (AFB) reactor. The wastewater COD level was 2000-3000 mg/L in simulation of real textile waste-water. The ATP content and the specific ATP contents o...

Due to its structure, hexamethylenetetramine (HMT) is a slowly biodegradable substance, hydrolysing in acid environment to ammonium and formaldehyde. Formaldehyde is toxic under normal conditions for biological treatment processes. Following an adaptation, a formaldehyde concentration of 1000 mg·l may become biodegradable both in aerobic and anaerobic conditions. Acidic conditions for hydrolysi...