Ceramic Disc Filters

Project Detail

NUCLEAR INDUSTRIES YANTAI TONCIN is a leading developer of filtration technology in China, and is China’s largest supplier of Ceramic Disc and Horizontal Vacuum Belt Filters.

In 2015 Roytec entered into a manufacturing agreement with Nuclear Industries YanTai Toncin located in the Shandong province of China.

Over and above being Asia’s largest Belt Filter manufacturer, Toncin deliver on average 200 sets Ceramic Disc Filters per annum.

Toncin’s sister company Heijing Ceramic, manufacture the ceramic disc’s which are the “heart” of the Ceramic Disc Filter operation.

Heijing Ceramic have a unique production process which includes:

  • Mixing of the raw materials for the body of the disc which are then formed in a mould and heat treated at 1200 Degrees Celsius for 72 hours
  • Further processing to ensure the correct shape, as well as the fitting of air-line and plate securing components.
  • At this point the disc is pressure tested at 5 bar under backwash conditions, prior to the ceramic surface being added.
  • The plate is further heat treated at 1000 degrees Celsius, to finish the Ceramic surface, before being allowed to cool for between 4 and 6 hours

Roytec Toncin Ceramic disc filters are available in sizes from 1 – 150m² and are always fitted with South African / European brand mechanical and electrical components to ensure parts availability.

A recent installation in Ferrochrome has shown the Toncin Filter to produce high vacuum and thicker cakes, with consequent increase in production as well as superior cake discharge moisture content.

Locally Roytec provide the following services:

  • Application assistance for most mining & mineral processes
  • Laboratory scale test work
  • Filter sizing, specification and integration with upstream & downstream processes
  • Process & mechanical guarantees
  • Project management to South African engineering standards
  • Erection supervision
  • Commissioning, optimization & training
  • Service level agreements, with consignment stocking of spares and on-site assistance.

The Ceramic Disc Filter is supplied mostly as a complete installation:

  • Slurry trough
  • Rotating central shaft with Ceramic Discs
  • Slurry agitation rake
  • All motors
  • Filtrate receiver and vacuum pump
  • In-line strainer for backwash water
  • Ultra-sonic cleaning devices including generator packs.

The central rotating shaft has discs attached, each containing 12 ceramic sectors.  The ceramic sectors are supplied in varying sizes and pore size.  The number of discs varies according to the filter area required.  The slurry trough has a rake type agitator which prevents coarse solids from settling in the trough

Vacuum is applied at high levels (-0.8 – 0.9kpa) via a distribution valve at the head of the filter, whilst the shaft rotates.  Slurry is drawn towards the ceramic disc and by a combination of the vacuum, as well as capillary action, the liquor is drawn into the disc and central shaft, and removed via the distribution valve.  The distribution valve consists of a fixed piece and a moving (rotating) piece.

The process cycles consists of:

  • Dewatering (under vacuum)
  • Drying (under vacuum)
  • Cake release (No vacuum)
    • The use of backwash water is automatically controlled via the distribution valve.

The filter cake, which detaches from the ceramic disc, when vacuum is cut-off, is assisted in discharge via scrapers.

Once per shift, and selected by the operator based on:

  • Filter throughput
  • Cake moisture
  • Cleanliness of Ceramic discs

the following Ceramic cleaning processes can be selected individually or in combination.

  • Backwash utilizing clean water
  • Acid wash by adding acid into the backwash water circuit
  • Ultra-sonic cleaners

Product Benefits

  • Higher throughput than conventional vacuum filters
  • Large filtration area on a small footprint
  • Average concentrate moistures of 7-8%
  • Ease of maintenance with limited consumable parts
  • Lower power consumption than conventional vacuum and pressure filtration
  • Good quality filtrate with minimal suspended solids
  • Low operator input or supervision requirement