Building Materials From Recycled Waste Building materials and technology development council

TECHNOLOGY FOR MANUFACTURING GYPSUM PLASTER BOARD

A plant has recently been set up in India to produce walling blocks, ceiling tiles and binder from Phosphogypsum.A plant has recently been set up in India to produce walling blocks, ceiling tiles and binder from Phosphogypsum.

The following steps convert phosphogypsum to commercially gypsum plaster boards:

  1. Grinding of calcined gypsum, and its storage.

  2. Proportioning and mixing of gypsum plaster with water. Set controller and filler is-added to this slurry with a small quantity of glass fibre as reinforcement;

  3. Casting of board with the board forming machine.

  4. Carrying the 'green' board on a belt conveyor until the core sets and edges are stuck.

  5. Cutting boards with a rotary knife into lengths of 1m to 6m before the 'green' board reaches the end of the machine belt.

  6. Drying of boards by passing them through a tunnel kiln. Hot-air/steam allow recirculation of air. Natural drying is possible for small production. Drying is a very sensitive operation requiring careful attention.

  7. Transferring of dry boards on to portable platform and transportation to the warehouse.