1. Discharge status of graphite tailings
(1) tailings discharge

The annual output of national quality graphite is about 500000 tons, and the annual discharge of mineral processing tailings is more than 6 million tons.

(2) mineral composition of tailings

The mineral composition of tailings generally includes mica, feldspar, quartz, tremolite, diopside, garnet, calcite, rutile, pyrite, graphite, chlorite, epidote, kaolinite, montmorillonite, ilmenite, sericite, etc.

(3) particle size composition of tailings

Although the particle size composition of tailings is different among graphite ores, the general particle size distribution is relatively standard, the particle size range is 0.4mm, and the coarse particle size is the main one.

(4) storage of tailings

Tailings dams have been built in crystal graphite concentrators all over the country. The tailings are stored in the tailings pond. Generally, 60% - 60% of the wastewater is returned to the concentrator for recycling after sedimentation treatment. The wastewater containing flotation agents such as terpenol, lime and particulate suspended solids shall be discharged up to the standard after treatment.

2. Utilization prospect of graphite tailings

(1) turning tailings into "secondary" resources

Implement the "Circular Economy Promotion Law" to comprehensively utilize tailings and turn abandoned tailings into "secondary" resources.

(2) recycling valuable minerals

Some tailings contain valuable minerals such as rutile, ilmenite, pyrite and muscovite, which can be recovered during beneficiation. A graphite mine in Shandong has a precedent of recovering rutile and pyrite in its tailings.

(3) using tailings to make building materials

The tailings from a certain place in Shandong were added with 6% cement and used as the base course of expressway, and good results were obtained.

Composite International hollow bricks were prepared by semi dry pressing of whole tailings and sintering at 1040 ~ 1060 ℃.

Non burning bricks with good properties were prepared by adding 8% gelling agent into the whole tailings.

(4) using tailings to make other mineral materials

Using graphite tailings, adding marble, acidified graphite, powdered graphite, fluorite and solid sodium silicate to produce composite protective slag.

After grinding graphite tailings to - 200 mesh, white carbon black is produced by precipitation method.

(5) reclamation and greening of graphite tailings pond

Good results have been achieved in covering the soil and planting trees in the storage of graphite waste tailings.