The control of sludge bulking by ozonation was studied on four parallel pilot-scale (110 l/d) biological nutrient removal systems. Bulking was caused by filamentous organisms which typically occur in nutrient removal systems, i.e. Type 0092, Type 0041 and Microthrix parvicella. Continuous dosing of ozone, at 1; 2 and 4 g O3 /kg mixed liquor suspended solids (MLSS).d resulted in a diluted sludge...

The short- and long-term effects of oxytetracycline (OTC) on the anaerobic ammonium oxidation (Anammox) process were evaluated. The OTC inhibition of Anammox was substrate-, and especially nitrite-, dependent. The IC50 of OTC in the batch tests on an Anammox mixed culture was calculated to be 517.5 mg L(-1). The long-term effects of OTC on the Anammox process were examined in a continuous-flow ...

Anaerobic digestion is an engineered methanogenic decomposition of organic matter under oxygen-free conditions and involves a mixed consortium of different species of anaerobic microoganisms that transform organic matter into biogas. The process is successfully used for the treatment of municipal sludge, animal manure, industrial sludge, and industrial and municipal wastewaters. Applications of...

Two pilot-scale membrane bioreactors were operated alongside a full-sized activated sludge plant in Tunisia in order to compare specific energy demand and treated water quality. Energy consumption rates were measured for the complete membrane bioreactor systems and for their different components. Specific energy demand was measured for the systems and compared with the activated sludge plant, w...

Deammonification is known as an efficient and resource saving sidestream process option to remove the nitrogen load from sludge liquors. The transfer of the intermediate product nitrite between both syntrophic groups of organisms - aerobic and anaerobic ammonia oxidizers (AOB) - appears very sensitive to process conditions such as temperature, dissolved oxygen (DO) and operating nitrite level. ...

Increased numbers of swine producers will be removing sludge from their anaerobic waste treatment lagoons in the next few years, due to sludge exceeding designed storage capacity. Information on availability of nitrogen (N) in the sludge is needed to improve application recommendations for crops. The objective of this study was to investigate possible effects of different companies and types of...

Efforts have been made in this study to stabilize the sewage sludge mixed with sugarcane trash in four different proportions: 20% (T(1)); 40% (T(2)); 60% (T(3)) and 80% (T(4)), under laboratory conditions using epigeic earthworm (Oligochaeta) Eisenia fetida. The composting potential of worm was also evaluated in 100% sewage sludge treatment (T(5)). The changes in chemical properties of substrat...

The degradation of sludge solids in an insulated reactor during Autothermal Thermophilic Aerobic Digestion (ATAD) processing results in auto-heating, thermal treatment and total solids reduction, however, the ability to eliminate pathogenic organisms has not been analysed under large scale process conditions. We evaluated the ATAD process over a period of one year in a two stage, full scale Iri...

Background and purpose: The performance of full-scale moving bed biofilm reactor (MBBR) was evaluated as an alternative for upgrading of Kish Island Mirmohana wastewater treatment plant. In this study activated sludge process upgrade to MBBR process and different operating parameters were compared. Materials and Methods: Effect of upgrading on different parameters such as organic loading rate (...

Polycyclic aromatic hydrocarbons (PAH) are regarded as environmental pollutants. A promising approach to reduce PAH pollution is based on the implementation of the natural potential of some microorganisms to utilize hydrocarbons. In this study Proteiniphilum acetatigenes was used for bioaugmentation of sewage sludge to improve the PAH removal. Bioaugmentation experiments were performed in paral...