Solids concentration simulation of different size particles in a cyclone separator

Research is needed to better understand the influence of cell volume and fertility on watermelon transplant size and field performance in order to determine the most economic production practices. `Jubilee' watermelon transplants were grown using a 4 x 4 factorial experimental design consisting of 4 cell volumes (30.7, 65.5, 147.5, and 349.6 cm3) and 4 fertility rates (0, 1/4, 1/2, and full-strength Hoagland's solution). Transplant shoot dry weight significantly increased as cell volume and fertility increased. Increasing cell volume linearly increased watermelon number/ha and tons/ha for early and total harvest in 1995. The average weight per watermelon significantly increased for early-harvested fruit but not for total harvest as cell volume increased in 1995. Soluble solids concentration linearly increased with increasing cell volume for early and total harvests in 1995. Cell volume had no significant influence on the harvest parameters measured in 1997. In 1995, increasing fertility linearly increased watermelon number/ha and tons/ha for early harvests. Increasing fertility increased the soluble solids concentration linearly for early-harvested watermelons in 1997 but not in 1995. Fertility rate had no significant influence on any of the other harvest parameters measured in 1995 and 1997. The growing conditions and disease pressure in 1997 reduced melons/ha, yield, and soluble solids content when compared to 1995 values. The half-strength Hoagland's solution produced the greatest number of watermelons/ha, tons/ha, and the highest soluble solids concentration in 1995 and 1997. Pretransplant nutritional conditioning had no significant effect on total `Jubilee' watermelon production in Louisiana for 1995 and 1997.

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Modeling of the Gas and Particle Flow in the Cyclone Separator using LES, RANS and Mathematical Models

The International Conference on Applied Mechanics and Mechanical Engineering ◽

10.21608/amme.2010.37560 ◽

2010 ◽

Vol 14 (14) ◽

pp. 1-10

Author(s):

Kh. Elsayed ◽

C. Lacor

Keyword(s):

Mathematical Models ◽

Particle Flow ◽

Cyclone Separator

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Impact of Feeding Activity of Silver Carp on Plankton Removal from a High-Rate Pond Effluent

Water Quality Research Journal ◽

10.2166/wqrj.2005.022 ◽

2005 ◽

Vol 40 (2) ◽

pp. 191-201 ◽

Cited By ~ 2

Author(s):

Nadia Berday ◽

Driss Zaoui ◽

Abdeljaouad Lamrini ◽

Mustapha Abi

Keyword(s):

Feeding Activity ◽

Silver Carp ◽

Treatment Plant ◽

High Rate ◽

Fish Pond ◽

Gut Contents ◽

Hypophthalmichthys Molitrix ◽

Technology System ◽

Solids Concentration ◽

Plankton Communities

Abstract The effect of silver carp (Hypophthalmichthys molitrix Val.) feeding activity on the plankton communities in a high-rate pond technology system (HRPTS) effluent was investigated over a period of 100 days. The experiment was conducted at the experimental wastewater treatment plant of the Agronomic and Veterinary Medicine Institute (AVI) of Rabat, Morocco, using a HRPTS in a fish pond receiving the plant effluent. The effluent was highly dominated by phytoplankton (99.95%). Silver carp could survive and grow in the fish pond. Production was 37 kg with a very low mortality rate (12%). The high specific intestine weight (7%) and intake rates of biomass and phytoplankton by silver carp (616 g kg-1 of fish day-1 and 1.6 x 1011 cell kg-1 of fish day-1, respectively) demonstrated the importance of the feeding activity of the fish. Zooplankton intake rates were lower (2 x 107 bodies kg-1 of fish day-1). The high intestine index (3 to 4.3 for fish sizes of 14 to 22 cm) and the dominance of phytoplankton in the gut contents (99.95%) confirmed an omnivorous/ phytoplanctivorous diet. Silver carp were efficient in removing plankton from the HRPTS effluent. The net removal yields of biomass were 285 g m-3 day-1 and 322 g kg-1 of fish day-1, 7 x 1010 algal cells kg-1 of fish day-1 and 8.7 x 107 zooplankton bodies kg-1 of fish day-1, with net removal rates of 47, 64 and 62%, respectively. The total suspended solids concentration decreased from 211 in the inflow to 112 mg L-1 in the fish pond.

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Membrane thickening of water works sludge

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0117 ◽

2001 ◽

Vol 1 (5-6) ◽

pp. 215-220

Author(s):

A. Gillighan ◽

S.J. Judd ◽

R. Eyres

Keyword(s):

Hydraulic Resistance ◽

Reasonable Agreement ◽

Chemical Cleaning ◽

Solids Concentration ◽

Significant Difference ◽

Layer Resistance ◽

Tubular Membranes ◽

Resistance Data ◽

Mechanical Cleaning ◽

Dynamic Layer

The efficacy of ultrafiltration (UF) and microfiltration (MF) membranes was assessed for the concentration of actual waterworks sludges using crossflow tubular membranes operated at constant trans-membrane pressure. The MF membrane gave higher initial fluxes than the UF membrane but after 10 min of filtration the flux value and its decline tended to be very similar for both membranes operating under the same conditions. All membranes gave permeate product water of <0.2 NTU and <100ppb coagulant at all times. For both membranes mechanical cleaning, with sponge balls, was at least as effective as acid chemical cleaning, indicating that no significant permanent internal fouling occurred for these membrane materials. Hydraulic resistance data indicated a significant difference in the dynamic layer resistance between the two membranes. Whilst the UF membrane had a hydraulic resistance 3.7 times that of the MF membrane, the dynamic layer formed on the UF membrane during operation displayed a maximum hydraulic resistance almost nine times lower than that of the MF membrane operating under the same conditions. Correlation of cake resistance R versus feed solids concentration C for all the data generated for t>0 demonstrated reasonable agreement with the expression R∝ca where a=0.37 in the current study. This trend has been recorded in previous reported studies, a varying between 0.33 and 0.62 depending on sludge dewaterability.

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Increased Stability of Anaerobic Digestion by Controlled Recirculation

Water Science & Technology ◽

10.2166/wst.1991.0574 ◽

1991 ◽

Vol 23 (7-9) ◽

pp. 1229-1237

Author(s):

Chaio-Fuei Ouyang ◽

Tain-Gen Chang

Keyword(s):

Substantial Reduction ◽

Gas Production ◽

Digested Sludge ◽

Significant Saving ◽

Methane Generation ◽

Sludge Digestion ◽

Solids Concentration ◽

Secondary Sludge ◽

Sludge Recycling ◽

Growth System

The treatment characteristics of municipal sludge were investigated by the anaerobic activated sludge digestion (AASD) system. This study used the suspended growth system and mesophilic temperature in the digestors and separators; the system achieves a more stable and improved process; such a process configuration offers the possibility of a substantial reduction in the total volume necessary for efficient stabilization. This study presents data indicating that the AASS system is feasible. In general, with an applied solids concentration of TS= 2%, the nonbiodegradable portion of the substrate concentration contained in the primary and secondary sludge was found to be 40.6% and 35.1% on the basis or TVS and COD, respectively. This study also provides evidence that the reactions at a recycling ratio of R=1 and R=3 are considerably more stable than those achieved in conventional or other recycling ratio digestors with a HRT of 9 days or longer. The gas production and bioactivity is also higher than that normally produced by the conventional single-stage digestion system. The experimental results also indicate that the dilution rate exceeds the maximum specific growth rate as the HRT is decreased from 9 days to 6 days. The significant saving in reactor volume and enhanced methane generation should offset the energy required for digested sludge recycling.

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Nitrogen Reduction – Volume Demand

Water Science & Technology ◽

10.2166/wst.1992.0500 ◽

1992 ◽

Vol 25 (4-5) ◽

pp. 233-240

Author(s):

T. Palmgren

Keyword(s):

Suspended Solids ◽

Age Factors ◽

Reduction Rate ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Aeration Tank ◽

Nitrogen Reduction ◽

Solids Concentration ◽

Yearly Average ◽

Nitrification Process

Due to the slow growth of nitrification bacteria at low temperatures, nitrogen reduction normally requires long hydraulic retention time during winter. Important for the nitrification process is the aerated sludge age. Factors influencing the sludge age are aerated volume, mixed liquor suspended solids concentration, organic loading and sludge yield. In an existing plant you cannot easily expand the volume and the load is difficult to decrease. But the suspended solids concentration can be increased by running the biological step with the contact stabilisation process. At the Käppala Association sewage treatment plant in Lidingö just outside Stockholm, one of the six aeration tanks has been reconstructed for full scale nitrogen removal experiments. In this tank the old aeration system has been replaced with rubber membrane diffusers. Further more there are several zones separated by walls in the tank. The tank can thereby be run with great flexibility. By running it with the contact stabilisation process, the sludge age has been improved by a factor between 1.5 and 2 and thereby it succeeds in keeping the nitrification bacteria in the system even during snow melting. At temperatures of about 9 °C and hydraulic retention times of less than 3 hours in the contact zone there has been a nitrification degree of up to 50 to 60 %. The experiment was conducted with a stabilisation zone of up to half the total volume of the aeration tank. The main purpose for the experiments during the winter seasons was to improve nitrification. Keeping the nitrifiers in the system had been a crucial problem during previous years. When the nitrifiers were lost with an increased flow and decreased temperature the nitrification process didn't restart until the temperature was increased and the load decreased. Usually this didn't occur until the middle of the summer meaning a loss of nitrification for up to six months. In Sweden there is a goal set for 50 % nitrogen reduction for the plants in the Stockholm region. At Käppala we manage to keep 60 to 70 % nitrogen reduction during the warm season, that is from July to December. If we can keep up the nitrification the whole year we can achieve 50 % as a yearly average under normal conditions even though we can't keep the nitrogen reduction rate as high during the cold season.

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Temporal Variability of Suspended-Solids Concentration in the Estuarine Channel of Patos Lagoon, Southern Brazil

Water ◽

10.3390/w13050646 ◽

2021 ◽

Vol 13 (5) ◽

pp. 646

Author(s):

Rafael André Ávila ◽

Priscila Mulattieri Suarez Orozco ◽

Mauro Michelena Andrade ◽

Osmar Olinto Möller

Keyword(s):

Temporal Variability ◽

Suspended Solids ◽

Southern Brazil ◽

Patos Lagoon ◽

Reliable Technique ◽

Acoustic Data ◽

Solids Concentration ◽

Estuarine Hydrodynamics ◽

Inflow Conditions

The assessment of suspended-solids dynamics is crucial for the effective monitoring of estuarine environments. As the recurring in-situ sampling is usually problematic, the calibration of the backscattering from acoustic Doppler profilers has shown to be a reliable technique to estimate the suspended-solids concentration (SSC) in estuaries and rivers. In this study, we obtained a linear model that provides SSC estimates for the estuarine channel of Patos Lagoon by calibrating turbidity and acoustic data with in-situ concentration samples. The model output was analyzed in terms of its relationship with estuarine hydrodynamics and temporal variability. In this estuary, the supply of suspended solids is known to be due the runoff from its main tributaries, but also through the exchanges between the estuary and the coastal ocean. Both sources provide sediments and organic solids which affect water quality, geomorphology, and harbor operations. Results show that SSC is strongly linked to estuarine hydrodynamics, where concentrations increase with streamflow. During outflow periods, higher concentrations are associated with river runoff, whereas with inflow conditions they are induced by southern and southwesterly winds. However, relationship between SSC and streamflow is asymmetrical, meaning that the largest concentrations are majorly linked to outflow currents and downstream transport.

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