Dispersion of gas pollutant in a fan-filter-unit (FFU) cleanroom

2007 ◽  
Vol 42 (5) ◽  
pp. 1902-1912 ◽  
Author(s):  
Sheng-Chieh Chen ◽  
Chuen-Jinn Tsai ◽  
Shou-Nan Li ◽  
Hui-Ya Shih
Keyword(s):  
Filter Unit

Effects of hydraulic shock loads on small on-site sewage treatment unit

1997 ◽  
Vol 35 (8) ◽  
pp. 145-152 ◽  
Author(s):  
T. Panswad ◽  
L. Komolmethee
Keyword(s):  
Removal Efficiency ◽  
Sewage Treatment ◽  
Septic Tank ◽  
Hydraulic Shock ◽  
Treatment Unit ◽  
Shock Loads ◽  
Retention Period ◽  
Intermittent Feeding ◽  
Continuous Feed ◽  
Filter Unit

This research was to determine the effects of hydraulic shock loads by intermittent feeding on the removal efficiency of a small prefabricated real-sized septic tank/anaerobic filter unit. Besides the ‘control’ 24-hour continuous runs the other twice a day feeding periods covered 16, 12 and 8 hours per day, with the tank's retention time varying from 22.5 to 90 hours. It was demonstrated that the variation of the hydraulic feeding patterns ranging from 24-hour continuous feed to 8 h per day intermittent feed did not affect the performance of the system much. The percentage of BOD reduction was decreased from 85 to 82 and 81 percent for the feed times of 24, 16 and 8 hours per day, respectively. The tank capacity played a relatively major role in determining the removal efficiency of the process. The efficiency of BOD and SS reduction dwindled from 82.2 to 68.9 and 56.0% with the corresponding reduction in tank sizes from 90 to 45 and 22.5 hours retention, respectively. In any event, the unit could not satisfactorily remove nutrients. A retention period of not less than 48 hours is recommended if the Thai effluent standards are to be met. Equations for predicting the BOD removal capability were also developed.

scholarly journals ON THE MONITORING OF THE FILTER UNIT (MUD COLLECTOR) STATE

2018 ◽  
pp. 65-85
Author(s):  
V.V. Zholobov ◽  
D.I. Varybok ◽  
O.S. Nadezhkin
Keyword(s):  
Filter Unit

scholarly journals The Formation of Deposits on the Walls of the Pores in the Filtering Process

2019 ◽  
Vol 14 (2) ◽  
pp. 15-22
Author(s):  
Yu. A. Taran ◽  
A. V. Kozlov ◽  
A. L. Taran
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Driving Force ◽  
Nonequilibrium Thermodynamics ◽  
Driving Forces ◽  
Solid Particles ◽  
Original Structure ◽  
Small Particles ◽  
Filtration Process ◽  
Filter Unit

The aim of the work is to consider the mechanism of clogging the pores of the filter unit by small particles from the flow of filtrate inside them. Theoretical ideas about the process of filtering with the deposition of small particles from the filtrate on the pore walls and attribution of its fundamentals to restructuring from the original structure to the final structure allow to describe the process of clogging the pores using well studied concepts of known processes with phase transformations (in particular, crystallization). Based on this analogy and the approach to the description of the transformation of the "old" structure into a "new" one in time, using experimental data and their processing we calculated the rate of nucleation of the sediment centers (ωnucl), the linear (υlin) and volumetric rates of sediment plaques growth in the pores of the filter unit at different values of the process driving force, at different pressure difference in the system, and at different concentrations of solid particles in the suspension. Interpolation and extrapolation dependences were obtained for analyzing the mechanisms of sediments formation and growth for determining and calculating these (ωnucl, υlin) rates. Using the concepts of nonequilibrium thermodynamics to assess the influence of the driving forces we studied their influence (changes in the concentration of solid particles in the filtrate suspension and pressure drop across the filtering layer) on the dynamics of the filtration process. Using the data obtained it is possible to find the degree of clogging of through pores, which determines the filtration conditions, the filter septum type, and the filter overall dimensions.

A Study into the Removal of Iron from Ferruginous Ground Water Using Limestone Bed Filtration

1993 ◽  
Vol 27 (9) ◽  
pp. 23-28 ◽  
Author(s):  
P. G. Smith ◽  
A. Gaber ◽  
I. Hattab ◽  
H. A. Halim
Keyword(s):  
Pilot Plant ◽  
Iron Concentration ◽  
Initial Operation ◽  
Sand Filters ◽  
Sand Filter ◽  
Cheap Method ◽  
In Series ◽  
Liquid Depth ◽  
Filter Unit ◽  
Initial Results

A pilot plant consisting of limestone bed filtration and sand filtration has been built 15 km south of Cairo to serve about 400 people. The pilot plant consists of 3 limestone filter units operated in series and two sand filters. The limestone filters are 1.3 m × 1.3 m and have a media depth of 1.15 m, a liquid depth of 0.5 m plus 0.35 m free board. The pilot plant started operation in April 1991 and the initial operation of the pilot plant has shown that a packed limestone filter unit is a simple and cheap method of removing iron from ferruginous groundwater. The initial results have shown that when an inlet water of about 5 mg/l of iron is treated by one limestone filter and one sand filter at a flow rate of 0.9 m3/h, the treated water had an average iron concentration of 0.2 mg/l.

New filter unit launched

BDJ ◽  
2004 ◽  
Vol 197 (1) ◽  
pp. 53-53
Keyword(s):  
Filter Unit

Estimation of the Hydraulic Losses in the Work Shaft of a Gas Turbine Engine of a Gas Compressor Unit Under Various Operating Conditions

2019 ◽  
Author(s):  
Oleg Baturin ◽  
Aleksandr Krivtsov ◽  
Daria Kolmakova ◽  
Grigorii Popov
Keyword(s):  
Complex Shape ◽  
Operating Conditions ◽  
Compressor Unit ◽  
Fuel Gas ◽  
Turbine Engine ◽  
Hydraulic Losses ◽  
Flow Through ◽  
Filter Unit ◽  
Research Recommendations ◽  
Engine Power

Abstract The paper presents the results of numerical simulation of air flow through a modernized variant of the inlet filter unit (IFU) of the gas compressor unit GPA-Ts-16. A feature of the IFU design is that to reduce the load on the filter unit, it is proposed to be as compact as possible, which determines its complex shape. The goal of the study is to study the hydraulic losses and to develop the measures to reduce them, since it is found that every 100 Pa of losses in the inlet unit increases the consumption of fuel gas by 2.5 kg/h or reduces the engine power by 10.5 kW. Calculations of hydraulic losses in IFU are carried out for cases of absence or presence of wind with a velocity from 0 to 35 m/s, blowing from 5 main directions (0°, 45°, 90°, 135°, 180°). Studies are also carried out on the effect of the weather shield shape, presence of baffles under it, and the rack in the shaft on the hydraulic losses. As a result of the research, recommendations are provided for designing (changing the shape) of the inlet filter unit that eventually allow to propose a design that will reduce the hydraulic losses in IFU by 15% relative to the originally suggested variant.

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