High purity quartz sand has extremely strict requirements for Fe ₂ O Ⅲ
content, gas-liquid inclusion quantity, and product whiteness. Shanlu Heavy
Industry provides a complete set of purification equipment from calcination
water quenching to acid washing, flotation, and electromagnetic slurry magnetic
separation, suitable for the production of photovoltaic quartz sand, high-purity
quartz sand, and high-end board sand.
Taking a typical high-purity purification process route as an example: After
crushing and grading the raw ore, it is first sent to a calcination furnace for
high-temperature heat treatment. The calcination furnace designed by Shanlu
Heavy Industry is a rotary structure, and the furnace tube is made of
heat-resistant stainless steel or corundum material. The working temperature can
be set between 800 ℃ and 1100 ℃. The sand material rolls forward in the furnace
and is uniformly heated, which can cause the gas-liquid inclusions inside the
quartz particles to expand and break due to heat, while also promoting the
diffusion of impurity elements in the lattice to the surface. The calcined sand
quickly enters the cold water tank for water quenching, and the thermal stress
generated by rapid cooling causes minerals to crack along the interface, which
is beneficial for subsequent grinding and impurity dissociation.
After water quenching, the sand material is dehydrated and sent to the acid
washing reaction kettle for chemical leaching. The pickling reaction kettle is
made of 304 stainless steel lined with polytetrafluoroethylene or enamel
material, which is resistant to strong acid corrosion. The kettle is equipped
with a steam heating jacket and an anchor stirrer, which can achieve single acid
or mixed acid leaching of hydrochloric acid, oxalic acid, hydrofluoric acid,
etc. The reaction temperature is controlled between 60 ℃ and 90 ℃, and the
leaching time can be adjusted between 2-6 hours. After acid washing, the sand
material can be neutralized, cleaned, and dehydrated, and the Fe ₂ O3 content
can be reduced to below 30ppm.
For quartz sand containing silicate impurities such as feldspar and mica,
flotation purification is required after acid washing. Shanlu Heavy Industry
uses SCF flotation machine and adopts acidic or alkaline flotation process. By
adding amine collectors, impurities such as feldspar adhere to the bubbles and
float, while quartz remains at the bottom of the tank. The flotation machine
adopts a DC tank body, and the suction volume can be controlled by adjusting the
gap between the stator and rotor. The flotation concentration is 25% -35%, and
quartz concentrate with a purity of over 99.5% can be obtained.
Fine iron and titanium minerals may still remain in the flotation fine sand,
requiring further magnetic separation. Shanlu Heavy Industry is equipped with a
DCJ electromagnetic slurry magnetic separator at this stage. The device adopts
electromagnetic excitation, with a background field strength of up to 15000Gs.
The sorting chamber is filled with a magnetic medium, and weak magnetic
particles are captured by the medium when the slurry flows through. The DCJ
magnetic separator is suitable for fine ore slurry with a mesh size of -200 or
more, accounting for over 80%. During continuous operation, it can reduce the Fe
₂ O Ⅲ content to below 20ppm, meeting the requirements of first-class
photovoltaic quartz sand. The equipment is equipped with an automatic backwash
system, which can be cleaned online after the medium is blocked without stopping
the machine.
The above unit equipment can be centrally controlled by PLC. Shanlu Heavy
Industry is located in Shandong and has over 20 years of experience in mining
machinery design. Its products cover a full range of categories including
calcination, acid washing, flotation, magnetic separation, dehydration, and
drying. Shanlu Heavy Industry can provide customized process solutions based on
the customer's original quartz grade and inclusion characteristics.
In terms of equipment details, the calcination furnace cylinder adopts a
high-temperature resistant sealing structure with high thermal efficiency; The
acid washing reaction kettle is equipped with an acid mist absorption tower,
which meets environmental protection requirements; The impeller of the flotation
machine is covered with wear-resistant rubber, which has a long service life;
The electromagnetic slurry magnetic separator adopts water and electricity
separation cooling, with stable temperature rise control. These designs reduce
customer operational risks.
If you need equipment selection or incoming material testing data for
high-purity quartz sand purification line, please call Manager Zhang at
13583776655 (same as WeChat).