Belt filter - Wikipedia, the free encyclopedia. Diagram of a belt filter: sludge in the feed hopper is sandwiched between two filter cloths (shown green and purple). Hey, check out these auctions: Large 21 Life Size Vintage Antique Baby Doll Teeth US $44.87 (8 Bids) End Date: Tuesday Dec-15-2009 13:18:32 PSTBid now Cabbage Patch Kids 14' Girl, Vintage, Red Hair with Green Eyes Doll With Key For Adopimals by Cabbage Patch Kids. Many years ago, a young boy named Xavier happened upon an enchanted Cabbage Patch, where he found very special Little People who called themselves Cabbage Patch Kids. To help fulfil the Cabbage Patch Kids' dream of having. Find best value and selection for your Cabbage Patch Clown Doll Blonde with teeth Headmold 10 search on eBay. World's leading marketplace. Brace yourselves, grown-ups. In case you were wondering just how wired-up children are about their Cabbage Patch Kids, here's a mouthful to chew on. Clay Ellis, 31, an Arlington, Texas orthodontist, puts. Fluid is extracted initially by gravity, then by squeezing the cloth through rollers. Filtrate exits through a drain, while solids are scraped off into a container. The belt filter (sometimes called a belt press filter, or belt filter press) is an industrial machine, used for solid/liquid separation processes, particularly the dewatering of sludges in the chemical industry, mining and water treatment. Belt filter presses are also used in the production of apple juice, cider and winemaking. The system takes a sludge or slurry as a feed, and separates it into a filtrate and a solid cake. Applications. Belt filters are used both municipally and industrially in a range of areas including urban sewage and wastewater treatment, metallurgy and mining, steel plants, coal plants, breweries, dyeing, tanneries, as well as chemical and paper factories. The sludges from municipal use include raw, anaerobically digested and aerobically digested sludges, alum sludge, lime softening sludge and river water silt. When compared to other compression filters, belt filters use relatively lower pressures. This is of course subject to what lighting and ventilation will allow. Although all problems can be controlled by enclosing the filter, the enclosure reduces essential visibility and easy access to the machine for maintenance and repairs, leading to the expensive automation of the process. Unless the feed is well mixed from a digester, the use of belt filters will be more costly when processing a feed with varying solids content as this requires more operator attention, raising staffing costs. The type of feed may also affect the washing process. A poorly dressed female with bad teeth and rude with a cabbage mouth. Cabbage Mouths are usually dirty ole bastards at their wits’ end with fucked up shitty beards. Cabbage Patch Arms; cabbage patch. This Pin was discovered by Heidi A. Discover (and save!) your own Pins on Pinterest. Cabbage Patch Kids 12.5' Naptime Babies - Caucasian Tan Brunette/Blue Eye Girl (Leopard Jumper) $29.99 $34.99 Prime. Only 12 left in stock - order soon. The belt filter needs to be washed frequently which consumes large amount of water and time. The standard size can be used for solids concentrations of 1. For dilute sludge with feed solids of less than 1. This belt is used only in the gravity drainage area, not in the pressure zones. Depending on the required conditions of the cake, belt filters can have added washing stages and, infrared, hot gas or even microwave drying stages. For a feed or treatment process which produces unpleasant odours, volatile emissions, pathogens and hazardous gases like hydrogen sulphide. Solids concentration must be determined based on the concentration of primary solids in the feed and further solids that may precipitate during treatment. Solids concentration for a process will vary, thus the design must have the capacity to deal with varying feed solids concentration. For most sludge types the feed dry solids concentration is typically in the range of 1- 1. Again, the input solids loading is dependent on the sludge type and filter media, thus there is great variation in the dry solids loading rates of operating belt press filters. Typically, lower range solids loading rates fall in the range of 4. Cake thickness affects the permeability of the filtration media and the filtration rate. In some cases where filtrate recovery is important, it may be necessary to introduce a cake washing step. The primary objective of a belt press filter is to dewater process sludge and much of this dewatering occurs in the gravity drainage zone. The gravity drainage zone can achieve a 5 to 1. The dewatering achieved in the gravity drainage zone is adversely affected if the sludge is poorly spread across the belt or the residence time is insufficient. Dewatering can be promoted by the addition of surfactant and flocculation is achieved via the addition of high molecular weight polymer. Flocculation is improved with optimum polymer dosage, polymer dilution and mixing. The p. H of the feed slurry must also be monitored and controlled as low p. H decreases flocculation. Without sufficient conditioning, the gravity drainage is generally the limiting process step, but with optimum dilution the limiting process step can be shifted to the compression zone. There is an optimum number of rollers above which a drier product is not necessarily the result. Drier product is obtained from reduced belt speed rather than increased pressing time. Solids recovery is dependent on the filter media which must be selected for good permeability to promote dewatering but with pore diameter sufficiently small so that solids recovery is not greatly decreased. It is important that the belt press filter has an effective belt washing section so that blinding does not decrease the permeability of the belt. Dry solids content is a measure of the degree of dewatering. The degree of dewatering is increased when the belt speed is decreased. The following correlation relates input mass flow rate to belt speed. Thus to maintain industrial scale economic throughput at lower belt speed, the mass loading and width of sludge across the belt must be increased. It has been found that increasing the solids loading slightly decreases the dry solids concentration of the cake while significantly increasing the potential for sludge to overflow the belt. Increased lateral sludge migration means that sludge is escaping the edge of the belt and overflowing into the filtrate. Therefore, increased lateral sludge migration negatively impacts filtrate quality and dry solids recovery. Generally, the minimum design discharge cake thickness is 3. In general centrifuges and other competing technologies do not show a significant cost advantage compared to the belt press filter, for the same cake dryness. The cost of flocculant is often a major operating cost of dewatering equipment. Belt press filters in general have the lowest flocculant consumption for any of the listed processes excluding membrane filter presses and centrifuges. If increasing the feed solid concentration is not practical the addition of flocculants in a pre- treatment step has a similar result. The optimum dosage level of flocculant can be found by monitoring the viscosity of the slurry. Homogeneous cakes are desirable as if the feed slurry is too dilute the filter cake will contain higher moisture content as a result of stratification. The minimum feed concentration that results in a homogeneous cake is determined by observing a sample of the slurry. If rapid settling occurs the filter cake formed will not be homogeneous and the filtration rate is decreased. The filter cloth for a belt press filter should be as open as possible while maintaining the desired filtrate clarity or, if precoat is used, to prevent the loss of precoat. Lighter cloths produce a clearer filtrate and do not block as rapidly however their durability and life span is significantly shorter than heavier cloths. Seamed belts wear faster at the seam and cause wear at the rollers and the doctor blade. Zipper- type and clipper- type seamed belts are also available with the zipper- type having a longer life span as they provide less discontinuity. Seamless belts have the longest life span but are more expensive. Also it should be ensured that the belt press is compatible with a seamless belt. This is beneficial as it increases the filtration rate and decreases the cake moisture. The same advantages can be obtained by other drying methods such as passing dry steam through the deliquored cake to raise the temperature of the remaining moisture, or other drying methods can be utilised. When cake washing time is a dominating factor the maximum filtration rate will occur when the minimum cake thickness for discharge is achieved. The time required for washing is increased by the square of the ratio of cake thicknesses. For example, if the thickness of the cake is doubled the washing time will increase roughly by a factor of 4. Necessary post- treatment systems. Thus further treatment may be required for the filtrate before it is reused or discharged as waste. If the filter is downstream of a clarifier or thickener the filtrate (and wash water) can be recycled back into the clarifier to reduce the required filtrate clarity and allows for the use of more durable cloths. If recycling or reuse is not an option the filtrate should be discharged subject to legislation and license requirements. Further treatment of clarified water (filtration or chemical treatment) may be required before discharge. The polymer content makes filter cake from a belt press filter more suited to the aforementioned disposal methods than a cake conditioned with ferric chloride and lime which can occur with other dewatering processes. Cloth developments include the double weave which incorporates different yarn types to combine the specific advantages of each. The three belt system is more efficient with both a higher production rate and cake solid concentration at the expense of mechanical complexity. The technology has not been widely proven. A final dry weight solids content of 9- 1. Currently this technology is suited to small- scale applications (up to approximately 3. L of slurry per hour as the maximum belt size is 0. V- fold belts have a small footprint, low energy and wash water consumption and low capital and operating costs. They are self- tracking and can process sludge of varying composition, reducing operator involvement. Retrieved 5 March 2. LTD., 2. 01. 2, 0. October 2. 01. 3^ abcdhttp: //www. Komline- Sanderson, 2. Huang, Z., Hirschi, J., 2. Optimization of the Dewatering Performance of a Steel Belt Filter, Coal Preparation Journal, 2. Sparks, T.,Solid- Liquid Filtration . Collins Jr., A simple laboratory technique for determining belt- filter press operation, Environmental Technology Letters, 1. Oliver, J. 9. 48- 9. Id=C1. 40. 12, Bickert. K, V- Fold Belt Dewatering Technology, 3. Annual Qld Water Industry Workshop.
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