For exothermic fluid-phase reactions, a reactor which is cooled at the wall can exhibit multiplicity or parametric sensitivity_ Moreover, for heterogeneously catalyaed exothermic fluid-phase reactions, each of the catalytically active pellets in the reactor can exhibit multiplicity. Both forms of multiplicity can lead to thermal instability and as such have to he taken into account in reactor d...

in this article, a complete model for the mixed flow slurry reactor for polymerization of ethylene to high density polyethylene in the presence of ziegler-natta catalyst is presented. in addition to the effects of the multiple active sites, the effect of other important parameters such as the catalyst concentration, co-catalyst, hydrogen, monomer, impurities and pressure on the mass-average and...

Three dimensional heat and mass transfer in a metal-hydrogen reactor are numerically studied using the control-volume-based finite element method (CVFEM).The distributions of the temperature and the hydride density on the hydriding process is presented and discussed. The effects of dimensions reactor, imposed hydrogen pressure, inlet temperature and hydride thermal conductivity in the reaction ...

MIT has been developing a conceptual design for pebble bed reactors since approximately 1998, when a student design project concluded that in order to resurrect the nuclear power industry a new, innovative approach was needed, not only in reactor design but also in construction and operation. In their quest to identify the appropriate technology several key conclusions were reached. First was t...

Al-Ti-B master alloys are widely used in the aluminum industry as grain refiners for the control of the microstructure of the aluminum alloys. The SHS (self-propagating high-temperature synthesis) is an ex situ method that uses exothermic reactions to sustain the chemical reaction in a combustion wave. The advantages of SHS are the low energy requirement, simplicity and product purity. However,...

The lab-scale upflow anaerobic biofilm reactor was successfully operated for the treatment of synthetic wastewater with high nitrogen load by Anammox (anaerobic ammonium oxidation) process. During the entire period of operation, the reactor temperature was kept at 35±1°C. The operational strategy consisted of both increasing the ammonium and nitrite concentrations from 60 to 700mgN/L and from 8...

The wastewater discharged by poultry slaughterhouse industries are characterized mainly by high biochemical oxygen demand, high suspended solids and complex mixture of fats, proteins and fibers requiring systematic treatment prior to disposal. In this study, the performance of an upflow anaerobic filter reactor for treating Indian poultry slaughterhouse wastewater under low upflow velocity of 1...

The AHTR is a pool-type reactor with graphite matrix coated-particle fuel and a clean molten salt coolant [1]. Due to the very high thermal inertia provided by the pool configuration and molten-salt coolant of the AHTR, the thermal power of the AHTR can be substantially higher than an equivalent gas-cooled reactor, likely exceeding 2000 MW(t). The AHTR, with a molten-salt intermediate loop and ...

A numerical model was developed to simulate vapor deposition in high-pressure chemical vapor-deposition reactors, under different conditions of pressure, temperature, and flow rates. The model solved for steady-state gas-phase and heterogeneous chemical kinetic equations coupled with fluid dynamic equations within a three-dimensional grid simulating the actual reactor. The study was applied to ...

Butene-1 is produced from ethylene by dimerization reaction in a CSTR. Due to the exothermic reaction, serious temperature runaway occurs in the reactor. Therefore, it is important to stabilize the reaction temperature in order to maintain good quality product and safe operation. Temperature stabilization is also essential for maintaining optimal operation of high ethylene conversion and desire...