Two piece frame and two piece diaphragm filter plate

A filter plate assembly having a two piece frame and a two piece diaphragm for filtration of slurries comprising:

• (a) the two aligned and opposing frame pieces having adjacently disposed between them only two aligned and opposing diaphragm pieces without substantial other intervening structure between said diaphragm pieces and means for securing the two frame pieces together such that a liquid tight space is formed between the diaphragm pieces;
• (b) each frame piece comprising:
• (i) a mirror image of the other and each having inner and outer faces and inside and outside edges such that when the frames' inner faces face one another, an intraframe space is defined therein between inside edges without intraframe supports other than the diaphragm pieces, and a frame perimeter is established with the outside edges;
• (ii) a width between the inside edges and the frame perimeter, such width further comprising at least two frame conduit holes extending from the inner to outer face, and each said frame conduit hole adapted to receive means for diaphragm inflation fluid sealing and further adapted to align with the frame conduit hole of the other frame when the frames' inner faces face one another, forming a set of aligned frame conduit holes;
• (iii) each said frame conduit hole having a drainage cutout from an edge of the frame conduit hole generally nearest the inside edge on the inner face and extending to the nearest inside edge on the inner face, such drainage cutout adapted to provide drainage of filtrate liquid through the drainage cutout to the frame conduit hole, the filtrate flowing from a space between a filter cloth and an outer face of a diaphragm piece to the drainage cutout;
• and
• (c) each diaphragm piece comprising:
• (i) a mirror image of the other and each having inner and outer faces and an outer edge such that when the inner faces abut one another, outer edges of the diaphragm piece form a diaphragm perimeter that is substantially the same size and shape as the frame perimeter;
• (ii) at least two diaphragm conduit holes extending from the inner to outer face, each such diaphragm conduit holes located so that each aligns with a diaphragm conduit hole of an opposing diaphragm piece and a set of aligned frame conduit holes when assembled as in (a);
• (iii) at least one diaphragm conduit hole having extended there about at the outer face means for diaphragm inflation fluid sealing adapted to insertably form a seal with a frame conduit hole such that for an assembly as in (a) a fluid tight seal is made between the diaphragm conduit hole and one of said frame conduit holes, said means providing one or more ports from the diaphragm conduit hole to the liquid tight space between the diaphragm pieces.