Unlike many other types of equipment, thickeners have no standbys so if one goes out of commission it cannot be bypassed. Design and development of a novel thickener feedwell using. Service should mechanical or process problems arise, an experienced. A new experimental procedure for determining the solids flux curve is detailed. It is the most common process currently used for dewatering and for the concentration of sludge before digestion. Reliability over fifty years of experience in the design and manufacturing of sedimentation systems allows us to produce mechanisms that are characteristically troublefree in both installation and operation.
Effect of settling test procedure on sizing thickeners. Coe and clevenger1 assumed that a hindered settl ing zone ii will form in a thickener with a dilution ik having the minimum solid handling capacity. Dilution can be achieved through several different means. Combining the suspended solids concentration versus effective pressure. Steadystate, control, and capacity calculations for flocculated. Grant road, suite 106 tucson, arizona 85745 introduction feed dilution or solidsliquid weight the english word sedimentation ratio is derived from the latin verb sedere size and shape of the particulate meaning to sink down. Improve clarifier and thickener design and operation. If sludge is to be digested, thickening a blend of primary and waste activated sludge is a good practice. To illustrate, if waste activated sludge, which is typically pumped from secondary tanks with a content of 0.
It will treat m3 per day of suspension fed at 3% vv solids concentration and is to discharge underflow at. Otherwise, you will have a thin liquid with clumps of thickener in it. In high rate thickener hrt designs the rise rate or solids loading will dictate the required tank diameter for any given throughput. Measuring settling rates and calculating thickener capacity. The top thickener design approach adds ten innovative features to the thickener to provide a better process solution. Pdf the common thickener underpins the performance of most. As a solution for this problem, ferrum offers various prethickening systems and dosing devices. Citations are the number of other articles citing this article, calculated by crossref and updated daily.
Equipment design there are three main types of thickenersclarifiers. Bridgesupported mechanisms for tank diameters to 50 feet. Chapter 3 sludge thickening thickening is a procedure used to increase the solids content of sludge by removing a portion of the liquid fraction. C1 fermoy design submission environmental protection. Mip process recently completed the supply of four ccd thickeners from ldx for a copper project and a 35mo bolted thickener for a diamond operation. These simulations are used to determine the suitability of using a high density thickener rather than a high rate thickener. Soluble metal recovery improvement using high density thickeners 359 concentrate the slurry. Parekh2, and rick honaker1 1department of mining engineering 2center for applied energy research university of kentucky, lexington, ky 405060107 in collaboration with.
Process design manual sludge treatment and disposal. Development and pilotscale demonstration of deep cone tm. Roytec thickeners are used extensively in ccd applications. Mulcahy peter kos donald dean adrian tsuan hua feng report for division of water pollution control. In table i of the july article, improve clarifier and thickener design and operation, by joel christian pp. On the method of thickener area calculation based on the data. Thickener feed system design westech engineering, inc. Design and development of a novel thickener feedwell using computational fluid dynamics feed dilution is essential in operations where the feed solids concentrations are too high for effective flocculation and hence thickener throughput. Knowing how to size a thickener and determine the capacity required to handle a predetermined tonnage of a certain pulp, by overflowing a clear solution and obtaining the desired pulp density of thickener discharge, depends upon the settling rate of that particular pulp. The use of 3d dynamic models ensures integrated design. The similar components may be seen in the following links.
Service offerings can be divided into the following categories, which can be customised to client needs. A slurry gravity thickener designed with tilted plate in sedimentation area 203500m2. Homecrusher and mill crusher design calculation pdf. The settling velocity of the solids can be calculated by combining equations 8 and 9. Tank design uses 3d dynamic models and follows the sans api and other best practice international codes. In a bridge support thickener, such as the one shown below, the rakes and drive mechanism are suspended from a bridge that spans the diameter of the tank. Soluble metal recovery improvement using high density. Make freehand sketches of various ways the machine might be constructed, at the same time making any preliminary calculations which might be required to. Effect of settling test procedure on sizing thickeners article in separation and purification technology 122. The thickener area is directly obtained by differentiation of heighttime relationship and thickener depth can be evaluated by integration of the same. Calculation of thickener area and depth based on the data of.
Thickener design a continuous thickener is to be designed to deal with the effluent from the last question. Data will be presented to assist the design engineer in selecting the optimum unit processes for inclusion in a particular conceptual design. Gravity thickener sedimentation gravity thickener is essentially a sedimentation process similar to the process that occurs in all settling tanks. See also the thickener purchasing guide for packaging choices and servings per pack or case to help you determine the. Good results obtained 59% solids concentration location of the thickener in a wastewater treatment plant is important.
Article views are the countercompliant sum of full text article downloads since november 2008 both pdf and html across all institutions and individuals. They are usually only economical for diameters of fewer than 100 feet. Development and pilotscale demonstration of deep cone paste thickening process for phosphatic clay disposal final report daniel tao1, b. Thickening is a procedure used to increase the solids content of sludge by removing a. Good results obtained 36% solids concentration rotary drum w. Laboratory testing for design of thickener circuits joseph m.
C1 fermoy design submission environmental protection agency. As an example of a conventional thickener, taggart 1945 records the mt. In metallurgical practice, slime pulp consists of water, finely divided sand or granular particles, and colloidal material. At a given feed flux, there was good agreement between the solids flux curve determined by the method and continuous sedimentation results. Thus, as a part of our ongoing studies on l ube oil additives 1,2, studies were undertaken in this area with a. The settlingvelocity of the solids can be calcuiated by combining eqs.
A mathematical model for batch and continuous thickening of. As one can see in figure 3, the continuous simulation achieved an underflow suspended solids concentration of 59 wt% when the mud. Prethickening systems from ferrum for the solidliquid. As mentioned previously most of the highrate thickeners subassemblies are similar to those of conventional thickeners except for lifting devices that are not available on all units due to design restrictions. Attention is given to mathematics concepts which are used in. Chapter 5 sludge treatment islamic university of gaza. Depending on requirements, ferrum supplies the design, production and automation of the related system. Consequently, if this happens other thickeners have to take the extra load but if the plant incorporates just one thickener then the entire production line must stop. Thickeners are utilized in mineral processing for the purpose of solidliquid separation dewatering. For process and plantrelated reasons, the necessary feed conditions are often not achieved.
Mechanics and machine design, equations and calculators. Alternatives to natrosol as thickener in the production of emulsion paint akpa jackson gunorubon and uku misel department of chemicalpetrochemical engineering, rivers state university of science and technology, portharcourt, rivers state, nigeria email. Calculation of thickener area and depth based on the data. Shear stability and thickening properties of homo and copolymer of methyl methacrylate. These metrics are regularly updated to reflect usage leading up to the last few days. Before starting work on the design of any machine, get thoroughly familiar with what the machine is intended to accomplish and what special requirements or limitations must be considered. Improvement the stirring device is installed in the center of tiled plate thickener. Design calculations archives civil engineering downloads. The laws and principles controlling these conditions are not fully established, so that a complete discussion of them will not be attempted in this paper. Recall that gravity thickener operation varies between summer and.
Independent water filtration and separation equipment selection and modelling with many free online utilities sedimentation vessel design. The rotational flow in the feedwell is often carried into the body of the thickener and has the effect of blowing out on the side opposite to the feed entrance. Westech engineering has taken the next step in advancing thickener technology with our thickener optimization package top. Manual measurements are suitable in some applications but. Mip thickener design the following is a short cut to designing your own thickener. Shear stability and thickening properties of homo and. The basic operation of the gravity thickener is described in this lesson, focusing on the theory of operation,components found in.
You ma notice tiny lumps of thickener floating on top when you thicken a suppleme t, like ensure. These services can be targeted during capital projects for improved conceptual flow sheet design that is fit for purpose or for operational optimisation and troubleshooting. Conclusions 12 the calculational method of the thickener presented in this paper is based on simple equations, eqn 14 and eqn 20, especially useful for numerical calculations. Design 1 calculations the following calculations are based on the method employed by java module a and are consistent with aci31899. Case studies and generalized experiences will be discussed in detail to emphasize the numerous sludge treatment and disposal alternatives. Use a blender or food processor to make sure the thickener fully dissolves. Theory and application of thickener design a g waters abstract theory the sedimentation vessel has a constant crosssectionalarea the process is onedimensional and so there is no radial variation in concentration for any horizontallaycr iii the slurry can be treated as a continuum with a continuous liquid and solid phase interacting with each. Civil and structural engineering designs of conceptual designs, superstruture and substruccture design calculations of concrete and steel buildings. Outotec thickening technologies leading edge technologies for thickening and clarifying outotec is a global leader in the design, fabrication and supply of thickening and clarifying solutions for the minerals industry.
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