Optimization of key components of impact crusher based on “rock bed” mechanism

Applicability of the rock-bed filtration technique was investigated through pilot-plant experiments in Bangkok, Thailand. Polluted canal water was used as horizontal flow influent to two reactor channels filled with rocks. During one year operation, HRT, filter media, and aeration mode, were changed in several runs. The results showed that 1) the rock-bed filtration with aeration and the HRT more than 6 h can successfully improve polluted klong water by reducing the pollutants (e.g. 60-120mg/L of SS to 20-40 mg/L and 15-30 mg/L of BOD to 5-20 mg/L); 2) main removal mechanism seems to be the sedimentation resulting from the settleability enhanced by aeration, and the biofilm attached onto rocks also works in the reduction of soluble organic matter; 3) a combination of three rock sizes arranged in descending order showed best results; 4) longer HRT (13 h) produces better effluent but is not so effective if it exceeds 9 hours; 5) 60-70% of sediment IL was decomposed in a year, and porosity in rock beds reduced approximately 16%.

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Temperature Effects on Shallow Water Infiltration Rates in an Underground Rock Bed BMP

10.13031/2013.32144 ◽

2010 ◽

Author(s):

Michael Horst

Keyword(s):

Shallow Water ◽

Temperature Effects ◽

Water Infiltration ◽

Infiltration Rates ◽

Rock Bed

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Experimental and modeling approach to heat and mass transfer in a porous bed of a rock-bed heat accumulator

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2021.121654 ◽

2021 ◽

Vol 179 ◽

pp. 121654

Author(s):

Sławomir Kurpaska ◽

Hubert Latała ◽

Paweł Kiełbasa ◽

Maciej Sporysz ◽

Maciej Gliniak ◽

...

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Heat Accumulator ◽

Porous Bed ◽

Modeling Approach ◽

Rock Bed

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Cost Optimum Parameters for Rock Bed Thermal Storage at 550–600 °C: A Parametric Study

Journal of Solar Energy Engineering ◽

10.1115/1.4034334 ◽

2016 ◽

Vol 138 (6) ◽

Cited By ~ 1

Author(s):

Kenneth Allen ◽

Lukas Heller ◽

Theodor von Backström

Keyword(s):

Parametric Study ◽

Particle Diameter ◽

Thermal Storage ◽

Design Parameters ◽

Levelized Cost Of Electricity ◽

United States Dollar ◽

Capital Costs ◽

Mass Fluxes ◽

Rock Bed ◽

Biot Numbers

A major advantage of concentrating solar power (CSP) plants is their ability to store thermal energy at a cost far lower than that of current battery technologies. A recent techno-economic study found that packed rock bed thermal storage systems can be constructed with capital costs of less than 10 United States dollar (USD)/kWht, significantly cheaper than the two-tank molten salt thermal storage currently used in CSP plants (about 22–30 USD/kWht). However, little work has been published on determining optimum rock bed design parameters in the context of a CSP plant. The parametric study in this paper is intended to provide an overview of the bed flow lengths, particle sizes, mass fluxes, and Biot numbers which are expected to minimize the levelized cost of electricity (LCOE) for a central receiver CSP plant with a nominal storage capacity of 12 h. The findings show that rock diameters of 20–25 mm will usually give LCOE values at or very close to the minimum LCOE for the combined rock bed and CSP plant. Biot numbers between 0.1 and 0.2 are shown to have little influence on the position of the optimum (with respect to particle diameter) for all practical purposes. Optimum bed lengths are dependent on the Biot number and range between 3 and 10 m for a particle diameter of 20 mm.

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Physical model study of bedrock scour downstream of dams due to spillway plunging jets

Journal of the South African Institution of Civil Engineering ◽

10.17159/2309-8775/2020/v62n3a4 ◽

2020 ◽

Vol 62 (3) ◽

Author(s):

A Bosman ◽

G R Basson

Keyword(s):

Physical Model ◽

Linear Regression Analysis ◽

Scour Depth ◽

Model Study ◽

Fissured Rock ◽

Scour Hole ◽

Plunging Jets ◽

Concrete Blocks ◽

Rock Bed ◽

Equilibrium Scour Depth

The erosive power of a free-falling high-velocity water jet, flowing from a dam spillway, could create a scour hole downstream of the dam, endangering the foundation of the dam. Despite extensive research since the 1950s, there is presently no universally agreed method to predict accurately the equilibrium scour depth caused by plunging jets at dams. These formulae yield a large range of equilibrium scour dimensions. The hydrodynamics of plunging jets and the subsequent scour of a rectangular, horizontal and vertical fissured rock bed were investigated in this study by means of a physical model. Equilibrium scour hole geometries for different fissured dimensions (simulated with rectangular concrete blocks tightly prepacked in a regular rectangular matrix), for a range of flow rates, plunge pool depths, and dam height scenarios were experimentally established with 31 model tests. From the results, non-dimensional formulae for the scour hole geometry were developed using multi-linear regression analysis. The scour depth results from this study were compared to various analytical methods found in literature. The equilibrium scour hole depth established in this study best agrees with that predicted by the Critical Pressure method.

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Rock bed heat accumulators. Final report

10.2172/6697648 ◽

1977 ◽

Author(s):

M. Riaz

Keyword(s):

Final Report ◽

Rock Bed

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A cored Jurassic sequence from north Lincolnshire, England: stratigraphy, facies analysis and regional context

Geological Magazine ◽

10.1017/s0016756800025826 ◽

1982 ◽

Vol 119 (2) ◽

pp. 113-134 ◽

Cited By ~ 18

Author(s):

M. J. Bradshaw ◽

S. R. Penney

Keyword(s):

Facies Analysis ◽

Sediment Source ◽

The South ◽

Tectonic Feature ◽

Regional Context ◽

East Midlands ◽

Rock Bed ◽

Jurassic Sequence

SummaryA virtually complete Jurassic sequence recently drilled in north Lincolnshire is considered in a regional context. Liassic thicknesses and facies are largely unexceptional. The Frodingham and Pecten Ironstones are relatively thin and sandy, but the Marlstone Rock Bed is thicker and more ferruginous than elsewhere in the region. The Inferior Oolite is exceptionally thick and exhibits strong deltaic influence; equivalents of the Gristhorpe Member and Scarborough Formation of Yorkshire may be present. The Great Oolite was deposited in coastal-lacustrine-deltaic environments, more proximal than to the south or east. Thin Kellaways Clay separates the argillaceous Cornbrash from the Kellaways Sand. The organic-rich Lower Oxford Clay is thin owing to a basal non-sequence whilst the Upper Oxford Clay is condensed and less organic than in the East Midlands. The regressive West Walton Beds are followed by very thick Ampthill and Kimmeridge Clay sections beneath the Spilsby Sandstone. Regional thickness and facies analysis records the behaviour of the Market Weighton Block and reveals the influence of the Pennine High as both a positive tectonic feature and an occasionally active sediment source.

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