Apatite Rock Phosphate Manufacturing process

Construction Sand And Gravel

Sand and gravel typically are mined in a moist or wet condition by open pit excavation or by dredging. Open pit excavation is carried out with power shovels, draglines, front end loaders, and bucket wheel excavators. In rare situations, light charge blasting is done to loosen the deposit. Mining by dredging involves mounting the equipment on boats or barges and removing the sand and gravel from the bottom of the body of water by suction or bucket-type dredges. After mining, the materials are transported to the processing plant by suction pump, earth mover, barge, truck, belt conveyors, or other means. gravel sand processing plant

The material that passes through the scalping screen is fed into a battery of sizing screens, which generally consists of either horizontal or sloped, and either single or multideck, vibrating screens. Rotating trommel screens with water sprays are also used to process and wash wet sand and gravel. Screening separates the sand and gravel into different size ranges. Water is sprayed onto the material throughout the screening process. After screening, the sized gravel is transported to stockpiles, storage bins, or, in some cases, to crushers by belt conveyors, bucket elevators, or screw conveyors. The sand is freed from clay and organic impurities by log washers or rotary scrubbers. After scrubbing, the sand typically is sized by water classification. Wet and dry screening is rarely used to size the sand. After classification, the sand is dewatered using screws, separatory cones, or hydroseparators. Material may also be rodmilled to produce smaller sized fractions, although this practice is not common in the industry. After processing, the sand is transported to storage bins or stockpiles by belt conveyors, bucket elevators, or screw conveyors.

Apatite Rock Phosphate Manufacturing process

Superphosphate is manufactured by acidulating powder rock phosphate or apatite with dilute sulphuric acid in fixed proportions and the resulting slurry is allowed to cure for about two weeks to reduce the free acid and finally bagged. The main idea behind the acidulation is to convert the insoluble tricalcium phosphate content of the mineral into water soluble mono calcium phosphate.

In its processing, crushing, grinding SBM jaw crusher, impact crusher cone crusher and grinding mill may be used.

Apatite Rock Phosphate Specifications

For the manufacture of superphosphate, industries generally prefer rock phosphate containing a minimum of 70% BPL, though upto 63-65% BPL is also being consumed. Presence of iron and alumina should be as low as possible as they unnecessarily consume too much of sulphuric acid and also cause reversion of water soluble phosphoric acid in superphosphate. Sulica should also be as low as possible.Rock Phosphate Grinding Mill

For the manufacture of phosphoric acid by wet process, usually rock phosphate containing 30-32% P2O5 is required.

Apatite Rock Phosphate World Resources

North Africa

Morocco – Phosphate bed is found in sediments of the Eocene age for a distance of 320 km. between the Atlas Mountains to the east and the Atlantic coast in the west. The sediments are composed of shale, limestone and sandstone of marine origin. Phosphate occurs in limestone. The largest producing mine is the Khouribga (Kourigha). The phosphate rock from this mine is known as ‘Morocco Phosphate’ in trade, guaranteed to contain a minimum of 73% BPL. The thickness of the phosphate bed is 3 metres.

There is another mine at Louis-Gentil; the output from this mine is known as ‘Safi Phosphate’ with about 70% BPL guaranteed. The output of the Khouribga mine is sent to Casablanca port ant that of Louis Gentil to Safi port for export.

Algeria & Tunisia

Phosphate deposits of Eocene age occur on both sides of the border for a distance of 320 km. Mining is underground. The mineral worked is transported over cableways and narrow gauge railway owned by the mining company to Tebessa and transferred to the State railway for haulage to the port of Bone on the Mediterranean sea.

In Tunisia, the largest producing mines are at Moulares and Redeyef of the western extension of the deposits worked at Djebel Onk in Algeria. The bed varies in thickness from approximately 2 to 3 metres.

Coal Preparation Plants

A Coal preperation plant, nestled among the mountains. Coal Preperation plants generally use gravity process equipment to separate the refuse from the product (coal). Coal has a specific gravity between 1.35 and 1.5, while the refuse rock has a Specific Gravity of 2.1 to 2.3. Heavy Media is the most popular method of cleaning coarse sizes, jig plants are probably the second most common method used for coarse coal. Heavy media cyclones are being used more often for fines size fractions. Flotation is generally used to clean the -28 mesh size fraction, although spirals and heavy media cyclones have shown success in cleaning down to 100 mesh coal feed. Spirals are generally used for middling sizes ( 10 mesh to 60 mesh)

A flow diagram of a 400 ton per hour coal plant that produces both metallurgical coal and steam coal for power generation. Generally speaking, metallurgical coal is cleaner , has higher carbon content and is easier to process than the lower rank steam coals.

At this prep plant, all feed coal (ROM) is crushed to -2" before entering the plant circuits. The 2" x 10 mesh coal is screened and goes to the primary dense medium cyclone circuit. The 2" x 10 mesh coking coal is recovered from the refuse here. The middlings (-10 mesh x 60 mesh) are processed in the Secondary Dense Medium Cyclone Circuit to recover the coal here, this produces a higher ash coal and is used as steam coal. The coking coal product conveyor has an intermediate screen that enables material to be diverted in varying proportions to steam coal if necessary to enhance the coking properties.
The -10 mesh coal is deslimed at 100 mesh and then sized at 10 mesh x 100 mesh is processed in the spiral circuit to produce coking coal. The -100 mesh slimes and -60 mesh coal is then processed in the flotation circuit to produce coking coal.
The cleaned coal is dried in centrifuges and a belt filter press. Coarse rejects are crushed and then recombined with the fine tailings for disposal to the refuse fill. All ROM coal production is beneficiated in the coal preparation plant. Approximately 2,000,000 tonnes of cleaned coal is produced annually, with the plant processing about 3,000,000 tons of raw coal annually.Coal Preparation Plants