Horizontal rotating pan filters

One important variation of this type of filter is based on replacing the rigid outer wall necessary for containing the feed and the cake on the rotating table by an endless rubber belt. The belt is held under tension and rotates with the table. It is in contact with the table rim except for the sector where the discharge screw is positioned, where the belt is deflected away from the table 

Of the two versions, the tilting pan is more expensive, requires more floor space and high maintenance. Its advantages are, however, in its excellent cake discharge and control of wash liquor, and in the fact that larger sizes are available. 

---

Horizontal Rotating Pan Filters. These filters (Fig. 10) represent a further development of the tipping pan filter for continuous operation. They consist of a circular pan rotating around the central filter valve. The pan is divided into wedge-shaped sections covered with the filter medium. Vacuum is appHed from below. Each section is provided with a drainage pipe which connects to a rotary filter valve of the same type as in dmm filters. 

Fig. 10. Horizontal rotating pan filter (a) plan view (b) elevation.

Vacuum filters include the nulschc filter, enclosed agitated vacuum fillers, the vacuum leaf filter, the tipping pan filter, horizontal rotating pan filters, horizontal belt vacuum fillers, rotary vacuum drum lilters. and rotary vacuum disk filters. 

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... 

A horizontal pan filter is similar in operation to a vacuum Nutsche filter. It consists of shallow pans with perforated bases, which support the filter medium (see Figure 10.15). When a series of pans is arranged around the circumference of a rotating wheel, the operation of filtering, washing, drying, and discharging can be made automatic. 

The only types of filters that are suitable for phosphoric acid production (that can perform the sequence of all operations desired in the process of filtering gypsum) are the horizontal belt vacuum filters, which are offered by companies such as Fimco, Delkor, and Pannews the Bird tilting-pan vacuum filters, offered by Bird and Profile, ind the UCEGO rotating-table vacuum filters, offered by Rhone-Poulenc. 

Pan filters are continuous vacuum filters in which a horizontal circular surface which rotates around a vertical central axis forms the filtration area. The slurry is fed onto from above, the suction takes place in the direction of the force of gravity. Filtration on a pan filter in relation to the filter surface available offers a space-saving and economical solution for the dewatering of medium- and coarse-disperse systems (ores, crystalline salts, coarser grades of sand, etc.) in widely differing sections of industry. 

---