in pakistan besides pesticide contamination from agricultural field, the manufacturing industriesare also contributing relatively high quantities of toxic pesticides into the environment. these pesticides maybe toxic, mutagenic or carginogenic and may be bioaccumulated or biomagnified by the biota. because ofpersistent nature of pesticides, its removal from environmental system become difficult...

biological removal of lead was observed in this study during treatment of synthetic solutions of this heavy metal by a sample of waste activated sludge (was) having mlss concentration of 10000 mg/l. the objective was determining the capability of was in removal of lead in three different conditions of treatment: without any aeration and feeding, by simultaneous aeration and feeding and by aerat...

Seeding of nitrifying bacteria into the activated sludge process may decrease the necesary volume needs for a stable nitrification process. Both theoretical and experimental studies were carried out in order to evaluate the effects of seeding. A model was developed for prediction of the effects of seeding of nitrifying bacteria from a separate stage into the activated sludge process. Seeding te...

osa (oxic settling anoxic) process is one of the sludge reduction methods. in this method an anaerobic reactor is placed in activated sludge recycling line for sludge reduction purpose. this method is getting popular because of possibility of its application in currently operating waste water treatment plants. in this research, the performance of osa process in sludge reduction in sbr was impro...

there are more than 350 wastewater treatment plants distributed across different parts of oman. some of them produce large quantities of domestic sewage sludge, particularly this study focused on characterizing domestic sludge of six treatment plants that may contain various pollutants, therefore the proper management of domestic sewage sludge is essential.samples of domestic sewage sludge were...

This study combines a two-phase biological treatment system of activated sludge/contact aeration process by adding biological contact filters into the rear sector of the activated sludge aeration tank of the slaughterhouse wastewater treatment plant. This system keeps the advantages of complete mixing of substrates and microorganisms and flexible operation of the activated sludge process, and i...

Antisera were raised against nine strains which had been isolated from phenol-acclimated oil refinery activated sludge. Although several antisera reacted significantly with the activated sludge during a period of adaptation to phenol, only an antiserum against one of the isolates, Alcaligenes sp. E2, reacted with the activated sludge after the adaptation period. A kinetic pattern of phenol-oxyg...