Roller discharge

Knife Discharge String Discharge Roller Discharge Belt Discharge... 

Cake compression by flexible membranes is also used in the new automated vertical presses that use one or two endless cloth belts, indexing between plates (as described in section 12.2.2). Filtration and compression take place with the press closed and the belt stationary, the press is then opened to allow movement of the belt for cake discharge over a discharge roller of a small diameter. This allows washing of the belt on both sides (see Figure 12.4). Cycle times are short (typically between 10 and 30 min) and the operation is fully automated. Sizes of up to 32 m are available and the maximum cake thickness is 35 mm. 

Beyond the drying zone the filter cloth is removed by a system of rollers and on its route back, it is washed on both sides through jet pipes. This guarantees a consistently-high filter capacity. Discharge of the filter cake is carried out on the discharge roller by a sharp reversal of the filter cloth. In this way, it is also possible to remove very thin cakes - with the assistance of a discharge-wire additionally - quite effectively. 

The patented system (15) has stationary disks mounted inside a pressure vessel (horizontal vessel, vertical disks) which is mounted on rollers and can rotate slowly about its axis. A screw conveyor is mounted in the stationary center of rotation it conveys the cake, which is blown off the leaves when they pass above the screw, to one end of the vessel where it falls into a vertical chute. The cake discharge system involves two linear sHde valves that sHde the cake through compartments which gradually depressurize it and move it out of the vessel without any significant loss of pressure. The system rehes entirely on the cake falling freely from one compartment to another as the valves move across. This may be an unrealistic assumption, particularly with sticky cakes when combined with lots of sliding contact surfaces which are prone to abrasion and jamming, the practicality of the system is questionable. 

Paint-grinding roller mills (Fig. 20-52) consist of two to five smooth rollers (sometimes caUed rolls) operating at differential speeds. A paste is fed between the first two, or low-speed, rollers and is discharged from the final, or high-speed, roller by a scraping blade. The paste passes from the surface of one roller to that of the next because of the differential speed, which also apphes shear stress to the film of... 

A clean discharge is vit to good belt hfe. On the return run the carrying side of the belt is in contact with the return rollers, and any material adhering to it is ground in or deposited on the roller. Extremely sticky material may require a belt-cleaning device in the form of a... 

Cake disposal is relatively straightforward. Cakes may be discharged into bins that are trucked away or transported with a belt conveyor. With very large filter presses a well formed cake may weigh 200-300 kg per chamber and when it falls into a bin or onto a belt conveyor in one solid piece the impact is very high. Hence, special measures are required to break and de-lump the sole hard cake and, for belt conveyors, it is also recommended to increase the number of belt support rollers below the discharge chute at the point of impact. 

Selecting the suitable mechanism largely depends on the release characteristics of the cake from the filter media. Scraper discharge mechanisms generally tend to suit cakes that release readily whereas roller discharge mechanisms are best suited for cakes that exhibit thixotropic behavior. 

The twisting rubber hoses or o ringed elbows which connect the rotating pan necks with pipe and the wear plate to the face of the stationary valve The condition of the high impact nozzles mounted on the cloth wash manifold and, for wet cake discharge, the sluicing manifold The support rollers which take the vertical load of the entire machine and the horizontal thrust rolls that maintain the rotating frame concentric The toothed rim and sprocket which drives the pan filter... 

Rollers that support the vertical loads, centering thrust and others that move the rim away from the table in the discharge zone and maintain it under tension. 

Compounding Washdown, spills, leaks, discharges from wet air pollution equipment Solids from soapstone dip tanks oil from seals in roller mills oil from solids from Banbury seals sohds from air pollution equipment discharge... 

Belt type — a metal belt floated on water receives the molten material which breaks into flakes as the belt turns down over the return roller at (he discharge end. The cake is usually from l/8 to 5/8 inch thick. Thicker cake may require use of a top belt for addnl cooling... 

Roller discharge drum filter. (9) Based on total filter area. ... 

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