Talk:Settling

Settling and Sedimentation are distinct concepts

First, settling and sedimentation are very important concepts in earth sciences, namely sedimentology, so I find it very odd that this page is listed (only?) in the Chemical and Bio engineering project. Having said that, let me point out why they should not be merged.

Sediment transport has three parts, start, ongoing, end. The start can be erosion, or a mass movement that merges into a mudflow that merges into a hyperconcentrated flow that merges into a normal flow. The ongoing is by suspended transport, saltation, or bedload transport. The end is sedimentation, resulting in sediment accumulation, deposition, accretion. Erosion - transport - sedimentation is an established concept.

Settling on the other hand refers exclusivly to the tendency of suspended particles to fall under the influence of some force, notably gravity in an earth science context. Thus, the end point of settling is sedimentation. Just the end point! And sedimentation does not have to be preceded by settling. Boulders rolling on the bottom are not settling, for instance, since they are always matrix supported.

Thus, don't merge, but make the division of concepts strict as I have outlined here. 24.127.208.87 (talk) 17:49, 11 July 2010 (UTC)

Extended content

Setlling is of two types: 1) unhindered 2) hindered In hindered settling velocity gradients are affected by nearby particles. — Preceding unsigned comment added by 117.239.94.110 (talk) 17:35, 8 April 2013 (UTC) 213.253.35.226 (talk) 10:55, 18 December 2012 (UTC) High quality introduce of the ALTERNATIVE SEDIMENTATION THEORY AND EXAMPLES FOR PRACTICE APPLICATION YOU CAN GET IN THE WEB: https://www.researchgate.net/profile/Sadyrbek_Djighitekov — Preceding unsigned comment added by Dsadyrbek (talk • contribs) 04:38, 7 October 2016 (UTC) 'RECTANGULAR TANKS DESIGN BASED ON THE ALTERNATIVE SEDIMENTATION THEORY by Sadyrbek DJIGHITEKOV, ( Saji ), Ph.D http://www.linkedin.com/pub/sadyrbek-djighitekov/25/76b/298 — Preceding ) http://www.researchgate.net/profile/Sadyrbek_Djighitekov/ http://www.facebook.com/search/results.php?q=Sadyrbek+Djighitekov&init=public INTRODUCTION Settling Tank (or Sedimentation Basin) is a main construction of any Water and Waste Water Treatment Plants. But the traditional Settling Tanks design has one lack: there is not analytical formula for definition tank' depth. For different over flow rates various agencies and consulting firms are recommended side water depth: of 2 to 5 m. However, such approach was used in ancient Egypt and Rome before Christian era. Since 1904, more than 100 years ago, scientists developed the different sedimentation theories but they are devised on basis of Newton's law of universal gravitation and Stokes' equation. It was a great mistake, fatal error. An accordance with that theories it is impossible to calculate the main size of Settling Tanks - depth yet, because the theoretical equations do not describe the depth's dependence from the initial and required water concentrations, temperature and laminar regime of water flow. For decision above problem I am used Newton's Second law and Mesherski's equation /1/ and I am devised Alternative Sedimentation Theory. That theory was described in the book which has written in Russian in 1991 / 2 /. Thanks to Alternative Sedimentation Theory it is possible to calculate accurate sizes of Settling Tanks. The new calculation method is more correct and effective than traditional approach. Now, for English readers author is offering the main formulas for Rectangular Tanks design. '1. Definition of the Rectangular Tank’s depth' a) Definition the value of the sedimentation zone height ______________________________ Ho = 5,2√ ν t / ln [ Cн /( Cн -Cк ) ] (1) where, 5,2 - is a constant coefficient of resistance to settling particles in process laminar Italic textflow regime in tank; ν - is a kinematic coefficient of viscosity, мм² / sec; t - is a detention time to reach desired underflow concentration, sec; Cн и Cк - are the initial and desired water concentrations, mg/L. b) Definition the value of the sludge zone height: _________________________________ Hoc = 2 √ ν t / ln [ Cкo / ( Cкo – Cнo ) ] ( 2 ) where 2 - is a constant coefficient of resistance to settling particles in the inactive water environment; Cнo - is an initial sludge concentrations, mg/L; Cкo is a desired sludge concentrations, mg/L. c) Definition the value of the Rectangular Tanks depth: H = Ho + Hoc ( 3 ) '2.Definition of the Rectangular Tanks width:' W = Q / 3,6 H v ( 4 ) where Q - is a total water inflow, m³ / hr; v - is an average speed of water mass, mm/sec '3. Definition of the Rectangular Tanks length:' L = H² v ln [ Cн / ( Cн – Cк ) ] /(5,2)² ν ( 5 ) EXAMPLE. Determine the Rectangular Tank’s sizes if: - total water inflow: Q = 2000 m³/ hr; - initial water concentration: Cн = 400 mg/L; - desired water concentration: Cк = 10 mg/L; - initial sludge concentration: Cнo = 6000 mg/L - desired sludge concentration: Cкo = 16000 mg/L; - detention time to reach desired concentration: t = 2 hr or 7200 sec - temperature of the turbid water of 16°C and kinematic - coefficient of viscosity: ν = 1,1 mm²/sec; - average speed of water mass in settling tank: v = 10 mm/sec 'SOLUTION' 1. Determine the value of the Rectangular Tank’s depth: _________________________________ a) Ho = 5,2√ 1,1 × 7200/ ln [400/ (400 - 10)] = 2909 mm ________________________________________ b) Hoc = 2√ 1,1 × 7200/ ln [ 16000 /( 16000 – 6000)] = 259 mm c) H = Ho + Hoc = 2909 + 259 = 3168 mm or 3,17 m 2. Determine the value of the Rectangular Tank’s width: W = 2000/ (3,6 × 10 × 3,168) = 17,58 m 3. Determine the value of the Rectangular Tanks length: L = ( 3168 )² × 10 × ln [400/ (400 - 10)]/ (5,2)² × 1.1 = 84829 mm or 85 m REFERENCES 1. Loyzianski, A. M,& Lurye, A. I., 1983. Kurs teoreticheskoi mehaniki. T. 2. Dinamika – M.: Nayka 2. Djighitekov, S. 1991. Osnovy tehnologicheskogo rascheta otstoinikov. Bishkek: KyrgNIINTI 'ALTERNATIVE SEDIMENTATION THEORY FOR SETTLING TANKS DESIGN http://www.linkedin.com/pub/sadyrbek-djighitekov/25/76b/298 http://www.researchgate.net/profile/Sadyrbek_Djighitekov/ http://www.facebook.com/search/results.php?q=Sadyrbek+Djighitekov&init=public ABSTRACT Settling Tanks (Sedimentation basins) are the main construction in the water treatment plants and stations. There are about 95% of suspended particles sediment from turbid water. But when it is necessary to design the Settling Tanks we do not calculate main parameters, and usually we have used basically experimental data. At the present time for Settling Tanks Design Engineers are used traditional (conventional) sedimentation theory. But accordance this theory it is not possible to calculate accurately depth of Settling Tanks. What is the reason? The reason is next: more than 100 years ago Dr. A.Hazen (1904) suggested Newton's gravitational law. It was a fatal mistake because that Newton's law is considering just one external force in the water: gravitation. For decision this problem Dr. T. Camp (1946) suggested artificial approach: "ideal settling tank" for calculate depth theoretically. However, everybody can not believe in ideal things in practice. As a result specialists in the field of World Water Industry cannot calculate correct sizes of Settling Tanks because all handbooks and manuals are giving traditional sedimentation theory yet. Correct Settling Tanks Design can be done if specialists will consider three external forces acting to the any elementary volume of water: gravitation and forces of hydrodynamical pressure that normal to both sides of elementary volume and directed to the different sides. It is Newton's Second Law. Based on the Newton's Second Law I devised Alternative Sedimentation Theory. As a result everybody: scientist, engineer and even student can calculate correct sizes of Settling Tanks, create models and to choose effective of one. INTRODUCTION Sedimentation is the separation from water, by gravitational settling, of suspended particles that are heavier than water. It is one of the most widely used unit operations in wastewater treatment. Sedimentation basin is a main construction in the water treatment plants and stations. There is sediment about 95% of suspended particles from turbid water. But when it is necessary to design the sedimentation basins we do not calculate main parameters, and usually we have used basically experimental data. For example, in the AWWA handbook / 1 / has written: "Rectangular basins are generally designed to be long and narrow, with width-to-length ratios of 3:1 to 5:1. Chain-and-flight collectors are limited to about a 20-ft (6-m) width for single pass, but it is possible to cover a wider basin in multiple passes. Traveling bridge collectors can be up to 100 ft (30 m) wide, limited only by the economics of bridge design and alignment. In theory, asin depth should not be an important parameter either, because settling is based on overflow rates. However, in practice, basin depth is important because it affects flow-through velocity. Flow-through velocities must be low enough to minimize scouring of the settled floc blanket. Velocities of 2 to 4 ft/min (0.6 to 1.2 m/min) usually are acceptable for basin depths of 7 to 14 ft (2.1 to 4.3 m).... ". In the latter expression there is the main contradiction of modern theories in case of their realization in practice in the field of sedimentation basins design. On the other hand above expression leads to other questions: "If we have a great experience in the field of sedimentation basins design and there are enough standard dimensions for us why we remind ourselves about sedimentation theory? May be this theory is incorrect or the erroneous theory?” The correct theory usually helps to calculate the accurate sizes but not experimentally and approximately like right now. Thanks to correct theory we can evaluate effectiveness the kinds of sedimentation basins and to predict economic profits. For finding-out of the reason we shall consider the existing theoretical equations. DISCUSSION So, let's consider the main theoretical equations of the suspended particles in sedimentation process that used in the United States. At the present time the AWWA handbook / 2 / recommends flux theory. This theory considers four types of settling for particles: Type 1. Settling of discrete particles in low concentration, with flocculation and other inter particle effects being negligible. Type 2. Settling of particles in low concentration but with coalescence or flocculation. As coalescence occurs, particle masses increase and particles settle more rapidly. Type 3. Hindered, or zone, settling in which particle concentration causes inter particle effects which might include flocculation, to the extent that the rate of settling is a function of solids concentration. Zones of different concentrations may develop from segregation of particles with different settling velocities. Two regimes exist - "a" and "b" - with the concentration being less and greater than that maximum flux, respectively. In the latter case, the concentration has reached the point that most particles make regular physical contact with adjustment particles and effectively form a loose structure. As the height of this zone develops, this structure tends to form layers of different concentration, with the lower layers establishing permanent physical contact, until a state of compression is reached in the bottom layer. Type 4. Compression settling or subsidence develops under the layers of zone settling. The rate of compression is dependent on time and the force caused by weight of solids of solids above Under the influence of gravity, any particle having a density greater than 1.0 will settle in water at an accelerating velocity until the resistance of the liquid equals the effective weight of the particle. Thereafter the settling velocity will be essentially constant and will depend upon the size, shape, and density of the particle, as well as the density and viscosity of the water. For most theoretical and practical computations of settling velocities in sedimentation basins, the shape of the particles is assumed to be spherical. Settling velocities of particles of other shapes can be analyzed in relation to spheres. When the particle is solid and spherical ( here and in the further the author has accepted some different symbols than in handbook / 1 / ): ________________________ u = √ 4g ( ρs - ­ρ) d / 3 ρ CD ­ ( 1 ) where u is the settling velocity of the particle, g is the gravity constant, ρs is the density of the particle, ρ is the density of the water, d is diameter of the particle, CD is a drag coefficient. The drag coefficient is not constant but is dependent upon the Reynolds number. The value of CD decreases as the value of Re increases. In connection with this there are 4 Reynolds numbers regions are marked. The region 0.0001< Re < 0.2. is the laminar flow region, the equation of relationship approximates to CD = 24 / Re ( 2 ) when this relationship is inserted in Eq. ( 1 ), it becomes _______________________ u = √ g ( ρs - ­ρ) d² / 18 μ ( 3 ) which is known as Stokes law / 2 /. where µ is the absolute viscosity of the water and u, d, and ρ are as stated before. On basis this law were developed a number theories. The first of them is the "ideal" settling theory / 3 /. In accordance with this theory assuming that all particles settle discretely and that those which strike the bottom are removed, the absolute velocity path V represents the maximum elevation where particles of the smallest settling velocity V which will experience 100 per cent removal may be found. That is, a particle with settling velocity u' which enters the the basin at the water surface (at height "ho" above the bottom) will travel along the path U and be removed just as water moving at velocity U enters the outlet zone. The time t available for a particle to settle is: t = L / U ( 4 ) and so the critical settling velocity u' is: u' = ho U / L ( 5 ) The velocity U is: U = Q / ho W ( 6 ) where W is width of basin After the combination of this relationship with the previous two yields: u' = ho U / L = ho Q / ho W L = Q / WL ( 7 ) The quantity WL is the surface (bottom) area A of the basin, and u' = Q / A ( 8 ) Usually, in accordance with the theory of ideal settling u' = 0.048 cm/sec.with the surface loading Q/A of 1,000 gpd/sq ft. Equation ( 7 ) shows that settling efficiency for the ideal condition is independent of depth H and dependent only the tank plan area. This principle is sometimes referred to as Hazen's law. In contrast, retention time, t is dependent on water depth, H, as given by t = AH / Q ( 9 ) in reality, depth is important because it can affect flow stability if it is large and scouring if it is small / 2 /. But sedimentation basins seldom perform in accordance with ideal settling theory. Two factors are predominant in the departure of basin performance from ideality: currents and particle interactions. One approach for estimating the effect of currents is that devised by Hazen / 4 /: y / yo = 1 - [ 1 + u' / a ( Q / A ) ]‾ ª ( 10 ) where yo is the initial quantity of particles in a suspension possessing a settling velocity of u' y is the quantity of such particles which will be removed in the basin, a is the number of (hypothetical) basins in series. For a = 1 in Hazen's theory, only 50% of the particles with settling velocity u' (equal to the surface loading Q/A) will be removed, whereas 100% of such particles would be removed in accordance with ideal theory. Particle interactions manifest themselves in three ways, one of which accelerates settling whereas the others retard it. Settling is accelerated by the occurrence of flocculation within the sedimentation basin itself. In addition to flocculation, particle interactions may produce an effect known as hindered settling ( Type 3 ). The simplest and most widely used equation for estimating the extent to which settling is hindered is that devised by Richardson and Zaki / 5 /: Us = U' ( 1 - Ф )ⁿ ( 11 ) where Us is the hindered settling velocity of the suspension, U' is the unhindered settling velocity [ as calculated by Eq. ( 1 ) or ( 3 ) ], Ф is the volume concentration of particles in the suspension (volume fraction), and n is an exponent which, for spheres settling at Reynolds numbers less than 0.2, has a value of 4.65. Another simplest and most convenient relationship is represented by general equation / 2 / : Us = Uo exp ( - q Ф ) ( 12 ) where q is constant representative of the suspension Uo is settling velocity of suspension for concentration extrapolated to zero. RESULTS OF DISCUSSION 1. At the present time the traditional (conventional) sedimentation theory are based on the effect of gravity on particles suspended in a liquid of lesser density. The settling velocity of the particle determined on the basis of Stokes equation as the main calculation formula that inserted in the different theoretical equations. But this physical formula does not definite the sedimentation basin's geometrical sizes accurately. Especially, main of them it is a depth of basin. 2. In connection with above sedimentation basin design has contradiction : " In theory, basin depth should not be an important parameter either, because settling is based on overflow rates. However, in practice, basin's depth is important because it affects flow-through velocity" / 1 / . But in practice basin's depth is assumed approximately. This incorrect approach is used in the water global industry more than 100 years. PROBLEM Why we have such contradiction between theory and practice? The matter is that scientists have taken a great interest to the private law for a special case: settling of particles in water. And the main question: what degree of water treating as a whole on an output from sedimentation basin became minor. As a result scientists have chosen Newton gravitational law and Stokes equation. It was the fatal choice from their party. They have absolutely forgotten, that it was necessary to consider the general case: degree of water treatment before and after sedimentation basins. In connection with above we have a question. The question is: " How we can calculate basin's depth as an important parameter in theory for application in practice? SOLUTION We live in a space age. And in our space age it is impossible to keep only by one law and to pray as on Maria's icon of the virgin. If scientists in the field of spacecrafts have been applied Stokes equation and studied speed of fuel particles from engines, in this case rockets would not take off for space. As is known, spacecrafts have a number engines supplied by fuel tanks. Engines are serially separated after full combustion of fuel and a spacecraft's mass is decreased. But a mass of the clarified effluent is decreased after sedimentation basin too, because the particles settled in basin and sludge is removed from the bottom. Essence of the phenomenon in both cases identical: it is loss of mass in both cases. What have made scientists in the field of spacecrafts design? They have used equation that devised by Ivan Mesherski in 1904 on the basis of Newton's second law: v dm / dt = F ( 13 ) where F is the sum of external forces m - is mass of the body that is changed depending on time t v - is average speed of body In order to show applicability of Mesherski's equation to еffluent of water from sedimentation basin and calculate basin depth in the first let we shall consider sedimentation process in the motionless settling column. In accordance with flux theory there are four settling regions / 6 /. But in practice we can not see these settling regions. We can see just two zones: settling and sludge. Now let's allocate in the settling column with the polluted water some the elementary volume of a liquid of the rectangular form. After that we shall set to themselves the task: to define depth of the elementary volume. 'Task # 1. Definition of section's depth of the elementary volume that has the rectangular form.' Let consider the case when the water movement is uniform and has some corner upwards. As a result of settling of particles is accepted, there is a change of water mass in the elementary volume. Here particles as though play a role of engine fuel in process of mass loss in the elementary volume of water. It is known from mechanics law / 7 /, that to the moving mass of any body the external forces are acting. For this case the Eq. (13 ) has: v - velocity of water mass movement t - time of water movement F - projection of external forces on the direction of water movement. Let's consider at the first external forces acting to the any elementary volume of water / 11 /. There next forces are acting: - Equally effective gravity of the water volume, directed vertically downwards: G = γωℓ (14) where γ - relative density of water; ω - the section square of elementary volume; ℓ - length of the elementary volume. - Forces of hydrodynamical pressure that normal to both sides of elementary volume and directed to the different sides P1 = p1ω; P2 = p2 ω; ( 15 ) The sum of projections of equally effective external forces on an axis of the liquid movement gives: v dm / dt = P1 – P2 – G cos α ( 16 ) Substitution yields ( 14 ) and ( 15 ), and cos α = ( Z2 – Z1 ) / ℓ where Z1 - is co-ordinate of the bottom section of elementary volume; Z2 - is co-ordinate of the top section of elementary volume in the Eq. ( 16 ) gives v dm / dt = p1ω – p2 ω – γ ω ℓ ( Z2 – Z1 ) / ℓ ( 17 ) Having increased and having divided the right part of the Eq. ( 17 ) on the gravity of the water stream, we shall receive v dm / dt = G [ ( p1 / γ ) – (p2 / γ) – Z2 + Z1 ] 1 / ℓ ( 18 ) It is known from the basic equation of water uniform movement: { [( p2 / γ ) + Z2] – [ ( p1 / γ ) + Z1]}1 / ℓ = i ( 19 ) where i - hydraulic slope Then the Eq. ( 18 ) can be written down: v dm / dt = – G i ( 20 ) On the other hand: G = m g and finally the Eq. ( 20 ) can be written down: v dm / dt = – m g i ( 21 ) The hydraulic slope for pipes of rectangular section is defined under the formula given in work / 8 /: i = λ v² / 8 R g ( 22) where R - hydraulic radius which is defined for the pipes of rectangular section under the formula: R = h / 2 ( 23 ) λ - dimensionless coefficient of friction in the pipes, depending in the first from of water movement rejim. In our case we have the regime of laminar flow, therefore it is possible to write down: λ = 64 / Re Reynolds number for the rectangular pipe and the channel is written in the form of: Re = v max 4 R / ν ( 24 ) where ν - kinematic coefficient of viscosity v max = 2 v ( 25 ) After substitution yields (23) and (25) the formula (24) can be written down: Re = 4 v h / ν ( 26 ) As a result we shall receive: λ = 16 v / ν h ( 27 ) After substitution Eq. ( 23 ) and Eq. ( 27 ) in Eq. ( 22 ) we shall receive: i = 4 v ν / h² g ( 28 ) After substitution yield (28) in eq. (21) we shall receive dm / dt = – 4 m ν / h² ( 29 ) Now we can integrate the Eq. (29) by method of variables division. For this purpose we can write down Eq. (29) in the form of: ∫ dm / m = –(4 ν / h² )∫ dt After integration we can receive ln m = ln C – 4 ν t / h² ( 30 ) where C - a constant of integration which is defined from a condition: when t = 0; m = mн where mн - initial mass of the elementary volume of water Hence: ln C = ln mн, or C = mн At the end of t we have the result: ln mк = ln mн – 4 ν t / h² ( 31 ) where mк - final mass of elementary volume of water after time t. From Eq. ( 31 ) it follows that: _____________________ h = 2√ ν t / ln ( mн / mк ) ( 32 ) But we should leave from a micro level to a macro level: from definition of depth of the rectangular section to definition of depth of settling column ( Ho ). 'Task # 2. Definition of sedimentation zone depth of the settling column in which water with initial concentration' Сн is converted up to final Ск . For this purpose at first we shall express mass of water through their density. L. Prandtl / 9 / offered for the mixed liquids with various density following equation for definition of mass: m = ( ρ2 – ρ1) V ( 33 ) where ρ2 и ρ1 - densities of heavy and easy liquids; V - volume of the mixed liquid. For our case: mн = ( ρн – ρ) V mк = ( ρн – ρк )V where ρн и ρк - initial and final densities of water, ρ - density of pure water. It is known: ρн = ρ + Cн ρк = ρ + Cк Hence: mн = ( ρ + Cн ) V – ρ V = Cн V mк = [( ρ + Cн ) – ( ρ + Cк )] V = ( Cн – Cк ) V Thus we have the result: _______________________________ Ho = 2√ ν t / ln [ Cн / ( Cн – Cк ) ] ( 34 ) The resulted formula is fair only for the motionless vessel that filled by polluted water. But in the sedimentation basin the water's movement is uniform. How to account the influence of water movement rejim for definition of sedimentation zone depth ( height ) in basin? Task # 3. Definition of sedimentation zone depth in the basin. It is known: t = L / v Substitution of this in Eq. ( 34 ) gives: _______________________________ Ho = 2 √ ν L / v ln [ Cн / ( Cн – Cк )] (35) In Eq. ( 35 ) we have yield: ________ 2√ ν L / v ( 36 ) this looks like formula that defines thickness of the boundary layer at the laminar flow and its movement around of the thin motionless plate / 10/: ________ δ = 5,2 √ ν L / v ( 37 ) Eq.( 36 ) and Eq.( 37 ) just have different coefficients. It is explained that in the motionless vessel there is poorly expressed boundary layer on the border of phases: sludge - settling zone. In case of water movement in the sedimentation basin, thickness of the boundary layer on that phases is increased in 2,6 times, than in the motionless settling column. Therefore, it is necessary to adhere at calculations of sedimentation's basins already established coefficient - 5,2. And equation for definition of the sedimentation zone height of basin ( H ) will be: _________________________________ Ho = 5,2√ ν L / v ln [ Cн / ( Cн – Cк ) ] ( 38 ) The settling time usually is known and is always set and in connection with this the formula (38) is more convenient for writing down in the form of: ________________________________ Ho = 5,2√ ν t / ln [ Cн / ( Cн – Cк ) ] ( 39 ) Definition the value of the sludge zone height: _________________________________ Hoc = 2 √ ν t / ln [ Cкo / ( Cкo – Cнo ) ] Cкo - desired sludge concentration Cнo - initial sludge concentration Definition the value of the Rectangular Tanks depth: H = Ho + Hoc Definition of the Rectangular Tanks width: W = Q / 3,6 H v Q - total water inflow, m³ / hr; v - is average speed of water mass in settling tank, mm/sec. On the other hand we can use Eq. ( 34 ) for definition the depth ( height ) sludge оn the bottom of the basin(Hoc ). For research aims and analysis it is better Eq. ( 38 ) to write down in the form: L = H² v ln [ Cн / ( Cн – Cк ) ] / 27,04 ν ( 40 ) CONCLUSIONS: 1. On the basis of the body mass change law and bases of hydraulics analytical equations received for settling and sludge zones depths calculation. 2. These equations show an impact of suspended particles concentration, temperature and regime of water flow to the sizes of sedimentation basin and they are very important for research and practice design. 3. On the basis of above equations it is possible to develop mathematical models of Settling Tanks and to choose effective one. REFERENCES 1. American Water Works Association.2005. Water Treatment Plant Design, 4th ed. New York: McGraw-Hill. 2. American Water Works Association. 1999. Water Quality and Treatment, 5th ed. New York: McGraw-Hill. 3. Camp, T. R. 1946. Sedimentation and the Design of Settling Tanks. Transactions of ASCE 3 (2285): 895. 4. Hazen, A. 1904. On Sedimentation. Transactions of ASCE 53:63. 5. Richardson, J. F. and W. N Zaki. 1954. Sedimentation and Fluidization. Trans. Instn. Chem. Engrs. 32:35. 6. Tchobanoglous, G. 1991. Wastewater engineering: treatment, disposal, and reuse. 3rd.ed. New York: Metcalf & Eddy, Inc. 7. Loyzianski L. G and Lurie A. I. 1983. Kyrs teoreticheskoi mehaniki. t. 2. Dinamika - M.: Nayka. 8. Latushenkov A. M. and Lobachev V. G. 1956. Hydraulic - M.: Gosstroizdat. 9. Prandtl L. 1949. Gidroairomehanika. - M.: IL. 10. Shlihting G. 1969. Teoria pogranichnogo sloya. - M.: Nayka. 11. Djighitekov, S. 1991. Osnovy tehnologicheskogo rascheta otstoinikov. Bishkek: KyrgNIINTI

Relevant move request

There is a move request at Talk:Settle that watchers of this article may be interested in. Egsan Bacon (talk) 17:35, 2 November 2014 (UTC)

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Addition of Figure for Stokes Settling Model

Hi, I plan to make the addition of a figure I produced that is relevant to the discussion of Stokes' Settling regime are where it begins to fail. I believe it to be a useful illustration of where/how the Stokes Model breaks down for those looking for a quick use of the equations. Please discuss with me if you'd like to make edits to this addition. Cheers. -MMenczer MMenczer (talk) 19:07, 28 April 2023 (UTC)

Updating the title and legend of the figure added in the previous edit. MMenczer (talk) 01:25, 7 May 2023 (UTC)

Wiki Education assignment: CE200B - Environmental Fluid Mechanics

This article was the subject of a Wiki Education Foundation-supported course assignment, between 18 January 2023 and 28 April 2023. Further details are available on the course page. Student editor(s): MMenczer (article contribs).

— Assignment last updated by MMenczer (talk) 19:10, 28 April 2023 (UTC)

Mass movement in SA

Mudflow of Drakensberg 105.244.178.7 (talk) 07:33, 30 April 2023 (UTC)