The pickling tank is the core equipment in the purification process of
large-scale quartz sand production lines (with a daily processing capacity of ≥
3000 tons), mainly used to remove impurities such as iron, calcium, and aluminum
from quartz sand (with a requirement of impurity content ≤ 0.5% after pickling,
suitable for high-purity sand production needs). Its operating status directly
affects the purity of the finished product, production safety, and environmental
compliance. In actual production, acid pickling tanks are prone to problems such
as corrosion and leakage of the tank body, uneven removal of impurities during
acid pickling, and non-standard treatment of waste acid and gas, which are often
related to improper material adaptation, non-standard operation, and inadequate
environmental protection measures. Shanlu Heavy Industry is a technology-based
enterprise specializing in the research and development, manufacturing, and
service of complete sets of quartz sand equipment. With over ten years of
experience in adapting and optimizing pickling equipment, it can provide
professional support throughout the entire process from equipment selection,
anti-corrosion treatment to environmental compliance optimization, helping
enterprises achieve compliant production.
1、 Key points for adapting the core working conditions of the pickling tank
(professional advice from Shandong Heavy Industry)
The stable operation of the pickling tank is primarily based on the precise
adaptation of materials and working conditions to avoid various problems caused
by improper adaptation. Based on years of project experience, Shanlu Heavy
Industry provides the following compliance and adaptation suggestions: In terms
of materials, for tanks that come into contact with strong acid media such as
hydrofluoric acid and hydrochloric acid, priority should be given to using PTFE
lining or fiberglass material, accompanied by specialized acid and alkali
resistant anti-corrosion coatings to avoid chemical and electrochemical
corrosion caused by ordinary carbon steel materials; In terms of structure, the
tank volume is adapted according to the production line capacity, and acid
circulation channels and maintenance ports are reserved for subsequent
maintenance and even flow of acid; In terms of safety, cofferdams and emergency
neutralization tanks should be set up around the tank according to regulations,
equipped with acid and alkali resistant protective equipment and emergency eye
washers, in compliance with safety production standards.
2、 Common problem standard handling (compliant and implementable, without
exaggeration)
1. Corrosion and leakage of the tank: graded disposal to eliminate safety
hazards
Corrosion and leakage are often caused by damage to the anti-corrosion layer,
local wear, or cracking of the weld seam. The disposal should follow the
principle of "shutdown isolation first, and then graded repair". Slight
corrosion (partial detachment of anti-corrosion layer, without damaging the
substrate): After cleaning the corroded area, apply acid and alkali resistant
anti-corrosion coating that meets the standards, and conduct a sealing test
after curing; Localized perforation (aperture<50mm): acid resistant adhesive
is used to fill or patch steel plates for repair. After repair, non-destructive
testing is required and can only be reused after passing the inspection; Weld
cracking or extensive corrosion: The damaged plate needs to be replaced as a
whole, and if necessary, Shandong Heavy Industry should be contacted for
professional modification to avoid safety accidents caused by forced use.
2. Uneven acid washing and impurity removal: optimizing parameters to improve
impurity removal stability
Uneven impurity removal is mainly manifested by large fluctuations in the
impurity content of the finished product, with the core causes being uneven acid
concentration, improper temperature control, and insufficient material mixing.
Optimization measures: Equipped with an online monitoring device for acid
concentration, real-time control of acid ratio (such as mixing hydrofluoric acid
and hydrochloric acid according to industry standard ratios), to avoid excessive
or insufficient concentration; Stabilize the pickling temperature within the set
range (fluctuation ≤± 2 ℃) through a temperature control system to ensure
efficient dissolution of impurities; Install a low-speed stirring device inside
the tank, combined with an acid circulation system, to improve the uniformity of
material and acid contact, and control the fluctuation of impurity content
within 0.2%.
3、 Environmental compliance optimization (compliant with industry emission
standards)
The treatment of waste acid and exhaust gas in the acid washing process is
the core of environmental compliance and must comply with the relevant
requirements of the Comprehensive Wastewater Discharge Standard and the
Comprehensive Air Pollutant Discharge Standard. Shanlu Heavy Industry
Optimization Plan: The waste acid treatment adopts the "neutralization
precipitation+distillation recovery" process, which neutralizes fluoride and
heavy metal ions in the waste acid through lime milk. After meeting the
standard, some of the wastewater can be reused in the water washing process, and
the acid solution recovered by distillation can be recycled to reduce acid
consumption and discharge; The waste gas treatment is equipped with a secondary
alkali spray tower, which purifies the fluorine-containing waste gas and acidic
gas generated by acid washing, with a removal efficiency of over 90%, ensuring
compliance with emission standards; In terms of solid waste disposal, hazardous
waste such as waste acid residue and waste adsorbent materials are classified
and collected, and entrusted to qualified units for disposal, in compliance with
hazardous waste management regulations.
4、 Daily compliance operation and maintenance standards
Scientific operation and maintenance can effectively extend the service life
of equipment and reduce the probability of failure: daily inspections of tank
sealing, acid concentration and temperature, checking the operation status of
environmental treatment facilities, and keeping records; Clean up residual
materials and impurities on the inner wall of the tank every week, and check the
integrity of the anti-corrosion coating; Monthly calibration of concentration
monitoring, temperature control and other devices, and tightening of connecting
bolts; Conduct comprehensive anti-corrosion testing and maintenance on the tank
every quarter, and inspect the environmental treatment facilities to ensure
long-term compliant operation. Shanlu Heavy Industry can provide specialized
operation and maintenance training for enterprises to standardize operating
procedures.
Shanlu Heavy Industry has been deeply involved in the field of quartz sand
equipment for more than ten years, with standardized production bases and
professional technical service teams. Based on the production conditions, raw
material characteristics, and environmental protection requirements of the
enterprise, we can provide suitable pickling tank selection, customized
optimization, and after-sales support services. All solutions comply with
industry standards and environmental protection standards. At present, relevant
technical solutions have been provided to multiple quartz sand enterprises
across the country, helping them achieve purification standards and safe and
compliant production.
If your production line is facing problems such as corrosion and leakage in
the pickling tank, uneven impurity removal, and difficulty in meeting
environmental standards, or if you have needs for pickling equipment selection,
optimization and transformation, operation and maintenance training, please feel
free to contact Manager Zhang at 13583776655 or WeChat. Shanlu Heavy Industry
will provide professional and practical services to help the production line
operate smoothly and compliantly.