background: natural methods of wastewater treatment, such as wetlands, are simple, cheap and acceptable for developing countries, especially small and remote cities. the aim of this study was to evaluate the efficiency of typha latifolica in subsurface flow constructed wetland for wastewater treatment. methods: in this experimental research, the efficiency of typha latifolica in subsurface flow...

the effect of hydraulic retention time in a range from 1.0-5.5 days was evaluated in a laboratoryscaleanaerobic fixed bed reactor packed with a hybrid material composed of tire rubber and zeolite. underthese conditions, cod removal efficiencies varied from 28.3% to 82.1%, respectively. over the more than 6months of operation, no clogging was observed. the results obtained demonstrated that this...

A scale-up study has been performed with three different size reactors to establish the optimum operating conditions for the hydrogen production from synthesis gas by biological water-gas shift reaction using the photosynthetic bacterium Rhodosprilliunt rubrum. Optimum medium composition and operating conditions previously determined in a bench scale 1.25 L continuous stirred tank reactor (CSTR...

Due to high applicability of the fixed bed catalytic naphtha reforming reactors, hydrodynamic features of this kind of reactors with radial flow pattern are improved in this work by utilising computational fluid dynamics technique. Effects of catalytic bed porosity, inlet flow rate and flow regime through the bed on the flow distribution within the system are investigated.It is found that t...

This study describes the biological degradation of TNT by using induced aeration. Three plastic reactors were used. In each reactor 3 kg of soil were used. In order to increase the porosity of the soil, sawdust was added to soil. Textile wastewater treatment plant sludge was also added to soil. TNT at the concentrations of 1000 mg/kg of soil was added thereafter. Rhamnolipid biosurfactant at th...

Global models are useful in the analysis of fusion reactors due to the facility in computing and presenting the results in terms of comprehensive parameters. A general figure of merit, which encompasses all the relevant tokamak parameters, is introduced in this article by a convenient normalization of the global power balance equation. In this way, different hypothetical tokamak reactors can be...

Non thermal plasma (NTP) reactors packed with non-catalytic or catalytic packing material have been widely used for the abatement of volatile organic compounds such as toluene, benzene, etc. Packed bed reactors are single stage reactors where the packing material is placed directly in the plasma discharge region. The presence of packing material can alter the physical (such as discharge charact...

An acceptable long-term solution for used (spent) fuel from nuclear power reactors has evaded all countries engaged in the civilian nuclear fuel cycle. Furthermore, many countries are trying to develop interim storage solutions that address the shortage of storage in the spent fuel cooling pools at reactors. The United States has a particularly acute problem due to its adherence to an open fuel...

In the first and second stage nuclear program of Department of Atomic Energy (DAE), technologies are matured for Pressurised Heavy Water Reactors (PHWRs) and Sodium-Cooled Fast Breeder Reactors (FBRs). Pre-service-Inspection (PSI), In-Service-Inspection (ISI) and Post-Irradiation-Examination (PIE) procedures are carried out for mechanical components and structures/assemblies of these reactors, ...

The effect of sulfide toxicity on kinetic parameters of anaerobic organic matter removal in a UASB (up-flow anaerobic sludge blanket) reactor is presented. Two lab-scale UASB reactors (10.5 L) were operated continuously during 12 months. The reactors were fed with synthetic wastes prepared daily using glucose, ammonium acetate, methanol and nutrient solution. One of the reactors also received i...