MATHEMATICAL MODELING OF HEAT TRANSFER IN A HORIZONTAL HEAT EXCHANGE PIPE

It has been experimentally established that the ideal displacement model adequately describes the heat transfer process in a horizontal heat exchange pipe cooled by atmospheric air

Development of energy-efficient method for processing industrial waste

An energy-saving method for processing technogenic waste has been developed — a smelt layer with inversion phase as a combination of “ideal” mixing and “ideal” displacement regimes. On its basis, a new generation of melting unit was created - the “reactor inversion phase - rotary kiln”. Experimental data show that in the inversion phase layer the specific fuel consumption for processing the “poor” on zinc and “rich” on zinc slags is approximately the same. The latter provision contradicts the prevailing opinion of metallurgists that the processing of slag with a zinc concentration of less than 5% is unprofitable. Сalculation results demonstrate that in case of implementation of an industrial sample of “reactor inversion phase - rotary kiln for processing “poor” slag, compared to the Waelz kiln processing “rich” slag, the specific consumption of fuel will be reduced by 1.5-1.7 times and specific productivity will increase 1.4-1.5 times. The industrial realization of “reactor inversion phase -rotary kiln” would allow cost-effective processing of fuming slag dumps, Waelz clinker, “poor” zinc ores, enrichment tails and other non-ferrous metal wastes.

Calculation of a packed column for absorption of hydrogen sulfur from gases formed by separation of crude oil

According to the well-known calculating algorithm for the packed absorption column, the main technological parameters and geometric dimensions of the apparatus for hydrogen sulfide containing gases, formed during the separation of crude oil, are determined. A 2,5-n solution of monoethanolamine is selected as the absorbent. Comparative results of the calculations are showing, that the working pressure in the column should be 4 atm, since with their lower values, the flow rate of the absorbent and the size of the column are increasing. The increase in working pressure is impractical, since it will require a transition from centrifugal and compresses pumps to piston pumps. ∏ The obtained parameters were compared for an absorption column in which the flow structure of the gas and liquid phases corresponds to ideal displacement, with the calculation results when the flow structure in the gas phase corresponds to the ideal displacement mode (as in the standard calculation algorithm) and in the liquid phase to ideal mixing. It is shown that, with the Peclet number of longitudinal diffusion pe<40 the height and volume of the column increases by 10 and more percent and should be taken into account when packed columns, intended for absorption processes, are designed. At pe=30 the height and volume of the nozzle in the column increases by 27%. Another feature of the modelling and calculation of devices is a spike in concentration, meaning, that the lower part of the working line will cross the equilibrium. Calculations in thisparticular case show that at ≈ 11 the working line crosses the equilibrium and theoretically column height and volume →∞.

Modeling of Wastewater Treatment Process in a Flotation Setup with Ejection Aeration System Having a Disperser

The mathematical modeling of flotation process has been considered in this paper. It has been pointed out that in the event when there are different types of pollutants in water the generation of bubbles with wide size-consist is needed. A flotation setup with ejection aeration system having a disperser that allows generate the bubbles which size-consist is characterized by several sets with their own values of average diameters is considered. The mathematical model for flotation process description taking into account the division of bubbles into several groups in sizes and hydrodynamic situation in flotation chambers has been proposed. Based on proposed model have been obtained other models describing extraction of certain waste, considering their properties, in such a case the initial model has been complemented by stages of other processes: settlement stage during flotation of suspended substances with density higher than water density, self-floating stage during flotation of contaminations with density less than water density, and reverse stages during flotation of hydrophobic-hydrophilic contaminations. The example of time definition for the process of water treatment from suspended substances and oil products has been presented. It has been demonstrated that it is possible to considerate the two-chamber flotation setup with ejection aeration system having a disperser as a sequence of reactors providing ideal mixing and displacement. Taking into account the equations for the reactors providing ideal mixing and ideal displacement, and the proposed models for description of process passing in cameras, have been received dependences for determination of concentrations and cleaning time in each camera. The importance of mathematical modeling for flotation setups designing has been pointed out. Application of scientifically based approach at design allows create setups having bigger profitability and compactness at achievement of the required efficiency.

Analysis of the fault geometry of a Cenozoic salt-related fault close to the D-1 well, Danish North Sea

A normal detaching fault in the Norwegian-Danish Basin around the D-1 well (the D-1 fault) has been mapped using seismic sections. The fault has been analysed in detail by constructing backstripped-decompacted sections across the fault, contoured displacement diagrams along the fault, and vertical displacement maps. The result shows that the listric D-1 fault follows the displacement patterns for blind normal faults. Deviations from the ideal displacement pattern is suggested to be caused by salt-movements, which is the main driving mechanism for the faulting. Zechstein salt moves primarily from the hangingwall to the footwall and is superposed by later minor lateral flow beneath the footwall. Backstripping of depth-converted and decompacted sections results in an estimation of the saltsurface and the shape of the fault through time. This procedure then enables a simple modelling of the hangingwall deformation using a Chevron model with hangingwall collapse along dipping surfaces. The modelling indicates that the fault follows the salt surface until the Middle Miocene after which the offset on the fault also may be accommodated along the Top Chalk surface.