Denitrification of synthetic high nitrate waste containing 9032 ppm NO(3)-N (40,000 ppm NO(3)) in a time period of only 6h has been achieved in our previous study using activated sludge. The activated sludge culture was acclimatized by a stepwise increase in the nitrate concentration of synthetic waste. In the present work, studies were carried out on the changing microbial population of the sl...

Ultrasonic treatment of waste activated sludge is one of the possibilities to reduce excess sludge production through the mechanism of sludge disintegration and cell lysis. In the past, several attempts have been made to model the process of solubilisation of the particulate volatile suspended solid part of the activated sludge (VSS) into soluble COD (sCOD). However, the focus of these models w...

The toxic, genotoxic and teratogenic potential of a municipal sewage sludge was assessed using the micronucleus assay on the larvae of the amphibian Xenopus laevis and with the tobacco somatic mutation test using the yellow-green xanthi Dulieu mutant a(1)(+)/a(1) a(2)(+)/a(2). The teratogenic potential was assessed by means of the Frog Embryo Teratogenesis Assay-Xenopus (FETAX). Various doses o...

In the temperature range of 10 to 80 ºC and in a batch digester, a typical activated sludge was digested aerobically. Reaction rate constants were determined by measuring the amounts of volatiles removed from the suspended solids at different time intervals during the process. The maximum value of the reaction rate constant (0.45 d-1) occurred in the temperature...

原油には重質なワックスやアスファルテンが含まれており，これらは最終的にスラッジとして原油タンクの底に蓄積される。そのため，原油タンクの本来の貯蔵能力を回復させる，あるいはタンクの点検やオーバーホールを行うためには，定期的にタンク内のスラッジを除去する必要がある。従来，原油を用いた共油洗浄（COW工法）によって産廃として処理しており，そのために多額のコストがかかっていた。この問題を解決するために，新しい技術であるSludge Volume Reduction（SVR）を開発した。本技術のポイントは，スラッジから遠心分離機で再利用可能な油を回収し，回収した油（以下，回収油）を再スラッジ化することなく原油と混合することである。回収油の化学組成，特にアスファルテンとワックスを分析した。分析結果に基づき，回収油を原油に混合する際には，回収油を加温しつつ原油と乱流状態で混合することで，再スラッジ...

Transmissible spongiform encephalopathies (TSEs, prion diseases) are a class of fatal neurodegenerative diseases affecting a variety of mammalian species including humans. A misfolded form of the prion protein (PrP(TSE)) is the major, if not sole, component of the infectious agent. Prions are highly resistant to degradation and to many disinfection procedures suggesting that, if prions enter wa...

in the temperature range of 10 to 80 ºc and in a batch digester, a typical activated sludge was digested aerobically. reaction rate constants were determined by measuring the amounts of volatiles removed from the suspended solids at different time intervals during the process. the maximum value of the reaction rate constant (0.45 d-1) occurred in the temperature range of 55-60˚c. removal of ind...

key dissimilarities between thermophilic and mesophilic anaerobic digestion of waste activated sludge (was) were experimentally studied in this research. typical was with total solids (ts) concentrations of 30 and 60 g/l were digested anaerobically in a batch digester at mesophilic and thermophilic temperatures. solids reduction, total cod changes, the production of different volatile fatty aci...

background: phytoremediation is one of the methods used to remove contaminants and while being simple, cheap and efficient, does not cause environmental deterioration. the aims of this study were phytoremediation of soil contaminated by cd, the simultaneous survey of the influence of different electrical conductivity values, and comparison of two soil amendments including sludge and municipal c...