Chemical Engineering Commons^™

Selective Phenol Methylation To 2,6-Dimethylphenol In A Fluidized Bed Of Iron-Chromium Mixed Oxide Catalyst With O–Cresol Circulation, Witold Zukowski, Gabriela Berkowicz, Jerzy Baron, Stanisław Kandefer, Dariusz Jamanek, Stefan Szarlik, Zbigniew Wielgosz, Maria Zielecka

Witold Zukowski

Background 2,6-dimethylphenol (2,6-DMP) is a product of phenol methylation, especially important for the plastics industry. The process of phenol methylation in the gas phase is strongly exothermic. In order to ensure good temperature equalization in the catalyst bed, the process was carried out using a catalyst in the form of a fluidized bed - in particular, the commercial iron-chromium catalyst TZC-3/1. Results Synthesis of 2,6-dimethylphenol from phenol and methanol in fluidized bed of iron-chromium catalyst was carried out and the fluidization of the catalyst was examined. Stable state of fluidized bed of iron-chromium catalyst was achieved. The measured velocities allowed …

Low-Emission Combustion Of Alternative Solid Fuel In Fluidized Bed Reactor, Jerzy Baron, Beata Kowarska, Witold Zukowski

Witold Zukowski

No abstract provided.

Thermal Decomposition Of Selected Chlorinated Hydrocarbons During Gas Combustion In Fluidized Bed, Malgorzata Olek, Jerzy Baron, Witold Zukowski

Witold Zukowski

Background The process of thermal decomposition of dichloromethane (DCM) and chlorobenzene (MCB) during the combustion in an inert, bubbling fluidized bed, supported by LPG as auxiliary fuel, have been studied. The concentration profiles of C6H5CI, CH2Cl2, CO2, CO, NOx, COCl2, CHCl3, CH3Cl, C2H2, C6H6, CH4 in the flue gases were specified versus mean bed temperature. Results The role of preheating of gaseous mixture in fluidized bed prior to its ignition inside bubbles was identified as important factor for increase the degree of conversion of DCM and MCB in low bed temperature, in comparison to similar process in the tubular reactor. …

Incineration Of Municipal Sewage Sludge In A Fluidized Bed Reactor, Beata Kowarska, Jerzy Baron, Stanislaw Kandefer, Witold Zukowski

Witold Zukowski

In the present study reduction of nitrogen oxides using reburning technology, during combustion of sewage sludge (fuel I) and the mixture of sewage sludge, wasted bleaching earth and CaO (fuel II), was carried out. The experimental works were conducted in a laboratory-scale fluidized bed reactor (power up to 10 kW) with application of two types of beds: chemically inert bed (sand) and chemically active bed (CaO). The second combustion (reburning) zone in the reactor was formed by dosing into an area above the bed, additional gaseous fuel (propane). Obtained reduction in emissions of nitrogen oxides in both types of beds …

The Choice Of The Fraction Of Iron-Chromium Catalyst Powder Providing The Correct Fluidization Process, Jerzy Baron, Gabriela Berkowicz, Stanisław Kandefer, Witold Zukowski, Stefan Szarlik, Maria Zielecka, Wielgosz Zbigniew, Dariusz Jamanek

Witold Zukowski

Introduction

The synthesis in the fluid-bed catalytic reactor provides high efficiency by maximum use of surface of the catalyst. Iron-chromium catalyst is characterized by high activity and selectivity, that make it such an attractive bed for fluidized-bed reactor. The choice of the appropriate fraction of the catalyst is necessary to ensure a proper organization of fluid flow.

EXPERIMENTAL PART

The study involved three types of iron-chromium catalyst:catalysts DJ/6 and DJ/7 (are synthetized by Industrial Chemistry Research Institute in Warsaw) and TZC-3/1 catalyst (are produced in Zakłady Azotowe in Tarnowie -Moscicach S.A.). The studies also involved different fractions, which were obtained …

Low-Emission Combustion In A Fluidised Bed Reactor, Beata Kowarska, Jerzy Baron, Witold Zukowski, Jadwiga Zabaglo, Malgorzata Olek

Witold Zukowski

Regardless of the type of fuel and organization of the combustion process, usage of air as an oxidizer in this process is a source of nitrogen oxides emission. Significant increase in the emission occurs when fuel is itself a source of nitrogen. The nitrogen oxides formed in combustion processes, conducted in industrial processes, in power industry as well as in households pose a serious threat to the environment and human health when released to the atmosphere. Apart from solid fossil fuels, solid biomass is being increasingly used for energy purposes. However, it does contain significant amounts of nitrogen, usually exceeding …

An Explicit Method For The Packing Limit Management In Dense Gas-Solid Flow Cfd Simulations On Both Structured And Unstructured Grids, Alberto Passalacqua, Luca Marmo

Alberto Passalacqua

An explicit method for limiting the volume fraction of the dispersed phase in the CFD simulations of dense gas-solid flows is described and validated both on structured and unstructured computational grids. The procedure is based on the excess solids volume correction method proposed by Lettieri et al. (2003), which has been extended in this work to non-uniform grids made of cells having different shape and size. The method has been implemented in OpenFOAM and validated through the simulation of a fludised bed in which the superficial gas velocity has been reduced to a value close to zero.

Small Scale Incinerator For Biomass, With A Bubbling Fluidized Bed. I. Combustion Of Sewage Sludge, Jerzy Baron, Sylwia Chrupek, Stanislaw Kandefer, Malgorzata Olek, Malgorzata Pilawska, Jan Porzuczek, Jan Wrona, Witold Zukowski

Witold Zukowski

Results are presented, obtained when sewage sludge was burned in a purpose-designed industrial installation, comprising a 1.5 MW bubbling fluidised bed combustor. Dried sewage sludge was used in the tests. The combustion process was stable, and since the moisture content of the dried sludge was low, no auxiliary fuel was required. Analysis of the flue gases has shown that the concentrations of SO2 and NOx are somewhat elevated, on account of rather high combined S and N content in the sludge. The results have confirmed that the technological solutions used were correct and that they can be used for economically …

Burning Sewage Sludge From A Municipal Waste Water Treatment Plant – The Migreation Of Metals, Witold Zukowski, Jerzy Baron, Sylwia Chrupek, Malgorzata Pilawska

Witold Zukowski

The migration of selected heavy metals has been analysed when sewage sludge from a municipal waste water treatment plant was burned in a bubbling fluidised bed. It has been shown that manganese, lead, arsenic, mercury and cadmium, as opposed to chromium, nickel and copper, leave the reactor mainly via the gas phase. To reduce the emissions of heavy metals to the atmosphere associated with the thermal utilization of sewage sludge requires more effective flue gases cleaning than is possible with filters.

Utilisation Of Waste Fuels In A Fluidised Bed, Jerzy Baron, Malgorzata Pilawska, Malgorzata Olek, Witold Zukowski

Witold Zukowski

A 100 kW atmospheric, bubbling fluidised bed reactor was used to study the combustion of wood waste, sewage sludge and a mixture of sewage sludge and meat-and-bone meal. Steady operation of the combustor was possible, even if the fuel was abruptly changed. With sewage sludge, the flue gas concentrations of SO2 and NOx were relatively high, as the sludge fuel contained much higher concentrations of combined S and N than e.g. wood waste. Co-combustion of sewage sludge and meat-and-bone meal presented no problems and the composition of the flue gases was similar to obtained the combustion of sewage sludge from …

Progress In Extractive Metallurgy, Volume One, Fathi Habashi

Fathi Habashi

Progress in Extractive Metallurgy is a new series planned to publish reviews and original research in extractive metallurgy and mineral dressing. Emphasis is on theoretical fields (chemical and physicochemical), unit processes, engineering problems, as well as historical aspects. OUT OF PRINT. Available only as Xerox copy from Métallurgie Extractive Québec