Heritage Cases

Brief process description Zircon sand(U+Th) will be transported from either Richardsbay or Namakwa sands as raw material. It will then be stored in one-ton bags. Sand will be loaded into hoppers which feed the reactors. Each reactor capacity is 1000t/a of processed zircon sand. Processed zircon sand then is stored in the hopper. The scrubber system will also be installed around the reactor system for dust control. Processed sand is then fed into the mixer where colourants added separately. Coloured sand then fed to the furnace to be heated to high temperature. Furnace then feed product to the dryer, where hot hydrochloric acid will be used for washing. Acid will be stored on side in the bunded wall tank. Washed product is then milled to finer sizes and dried before packaging. The quantity to process 2000t per annum though process will start with 1000t per annum on one stream for few years. There will be scrubber system on the reactor and an emissions inventory will be conducted as part of the Air Quality study for the atmospheric emissions license. The PDZ plant: • A PDZ plant is at least 3 stories high and under a roof. The main components of the plant are three power supplies for each plasma torch (3 x 150 kW), a zircon feed hopper with feed control, three plasmatrons, a plasma reactor, a cyclone, PDZ product hoppers, a heat exchanger, filters and a KOH scrubber. • There are going to be two PDZ modules, one on commission and one on standby. The electrical demand of each PDZ unit is 500 kW. This includes the power for the plasma torches, all electrical motors (pumps, fans and screw feeders) lights, plugs and overhead crane. • The utilities consisted of demin water, cooling water, a cooling tower, an extraction fan, gaseous nitrogen and argon gas. Argon and nitrogen can be situated outside the building. • The PDZ plant top section must accommodate the main zircon hopper, the feed hopper and the screw conveyer. An overhead crane will supply the 2-ton zircon bags to fill the zircon main hopper. • The ground floor with overhead crane will accommodate a scale and 210 liter steel drums for the storage of the hot PDZ produce until it cools down. The PDZ module produces raw material for pigments production. • The 3 levels will be connected by stairs. • The pigment manufacturing process follows the following steps: 1. Homogenizing of the PDZ 2. Mixing and blending the PDZ with chromophores and mineralisers 3. Calcining 4. Crushing and pulverising 5. Washing 6. Milling 7. Drying 8. Pulverising and homogenising 9. Packing, bagging and storing. The waste water in the disposal plant will be processed for re-use, and the water that has gone beyond the re-use cycle will be taken away by tanker for disposal. No waste water will be discharged into the stormwater drain. Electricity requirements for the plant will be met without any changes to the existing electrical distribution network.