Short Description:

Vermiculite is a kind of layered mineral that contains Mg and degenerates secondarily from hydrated aluminum silicates. It is usually formed by weathering or hydrothermal alteration of biotite or phlogopite. Categorized by stages, vermiculite can be divided into unexpanded vermiculite and expanded vermiculite. Categorized by color, it can be divided into golden and silver (ivory). Vermiculite has excellent properties such as heat insulation, cold resistance, anti-bacteria, fire prevention, water absorption and sound absorption, etc. When baked for 0.5 ~ 1.0 minutes under 800 ~ 1000 ℃, its volume can be increased rapidly by 8 to 15 times, up to 30 times, with the color changed into gold or silver, producing a loose-textured expanded vermiculite which is not anti-acid and poor in electric performance. Vermiculite after the expansion process will take on layered flaky shape, with the proportion generally being 100-200kg/ m³( Due to the huge volume of expanded vermiculite, the transportation cost would be quite huge, so the exported vermiculite is usually types of unexpanded ).

Product Detail


Product Tags

Crude vermiculite specifications: 0.15-0.5mm, 0.5-1mm, 1-3mm, 2-4mm, 3-6mm,4-8mm , 8-16mm.

Physical and Chemical Properties of Vermiculite

Because of different degrees of hydration and oxidation, chemical compositions of vermiculite are not the same. The chemical formula of vermiculite is: Mg x (H2O)(Mg3—x)(ALSiO3O10)(OH2)












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Application of Vermiculite

In agriculture, vermiculite can be used as soil conditioner, due to its cation exchange and absorption, improve soil structure, water storage and soil moisture, develop the soil permeability and water content, make acidic soil change into neutral soil; vermiculite can also play a buffer role, hinering the rapid changes of PH value, make the fertilizer release slowly in crop growth medium, and allow to slightly excessive use in fertilizer for plant but is non-harmful. Vermiculite can also be provided to the crop itself contains K, Mg, Ca, Fe, and trace amounts elements of Cu, Zu. As absorption, cation exchange and chemical composition characteristics of vermiculite, so it plays a fertilizer maintenance, water retention, water storage, permeability and mineral fertilizers, and other multiple roles. The tests showed: put 0.5-1% expanded vermiculite mixed into fertilize, enable crop yields by 15-20%.

In gardening, vermiculite can be used for flowers, vegetables, fruit cultivation, breeding and other aspects, addition for potting soil and regulators, but also for soilless culture. As to be the nutrition grass-roots for planting potted trees and commercial seedbed, it is advantage of transplanting and transporting of plants. Vermiculite can effectively promote the plant roots development and seeds’ growth, can provide water and nutrition of the plants growing for a long time, and keep the roots temperature stable. Vermiculite can make the plant get enough water and mineral on the initial stage, promote the plants grow faster, and increase the production.

Expanded vermiculite, paved on the roof, will play a very good heat insulating effect, making the building warm in winter and cool in summer. Using vermiculite bricks into the partition wall of high rise or using vermiculite blocks as partition materials into hotels or entertainment centers, effects of sound absorption, fire proof, heat preservation and so on will be fully displayed and the building will also be reduced of its load.

Tiny air compartments forms after vermiculite’s expansion, enabling the expanded vermiculite become a porous sound insulation material. When the frequency is 2000C / S, the sound-absorbing rate of 5mm thick vermiculite is 63%, 6mm 84% and 8mm 90%.

Vermiculite is great in resisting frost as its capacity and strength keeps the same even after it goes through 40 times of freeze-thaw cycle experiments under -20℃. It is porous and has absorption property. It can keep heat and prevent condensation. Besides, it can absorb radiation rays, therefore vermiculite boards can be placed inside laboratory to substitute expensive lead boards to absorb up to 90% of scattered rays. 65mm thick vermiculite is equivalent to 1mm thick lead board.

Expanded vermiculite powder was made by vermiculite ore, calcined at high temperature, screening, grinding. Main specifications are: 3-8mm, 1-3mm, 10-20mesh, 20-40mesh, 40-60mesh, 60mesh, 200mesh, 325mesh, 1250mesh. Applying in: housing insulation equipment, domestic refrigeration device, car muffler, sound insulation laster, safe and cellar lined pipe, boiler retaining thermal clothing, iron ladles, firebrick insulation cement, automotive insulation equipment, aircraft insulation equipment, cold storage insulation equipment, bus insulation equipment, wallboard water cooling towers, steel annealing, fire extinguishers, filters, cold storage, linoleum, roofing panels, cornices, dielectric gates board, wall paper printing, outdoor advertising, paint, increase the viscosity of the paint, photographic soft wood fire wood fire card paper, golden and bronze ink, paint the outside supplements.

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