Difficulties in selecting calcium carbonate? One article answers all common questions

Common problems in the entire process of purchasing and using calcium carbonate

一、 The most commonly asked questions during the procurement selection stage

1. How to choose between heavy calcium and light calcium? -Customers cannot distinguish between heavy calcium carbonate and light calcium carbonate, and do not know which one to use in their industry.

-Concerns: price, oil absorption value, liquidity, coverage, filling amount, stability

2. How to choose the appropriate mesh/particle size? -325 mesh, 600 mesh, 800 mesh, 1250 mesh, 2000 mesh... used in plastics, rubber, coatings, papermaking, which correspond to them

-Is finer the better? Being refined leads to high costs and difficulty in dispersion, which in turn causes problems

3. How much whiteness is considered qualified? -Low end filling below 90 degrees, mid-range 90-94 degrees, high-end above 94 degrees

-Insufficient whiteness can affect the appearance of the product, causing yellowing and darkening

4. Are moisture, iron content, and insoluble substances in hydrochloric acid important? -High moisture content: prone to clumping, affecting extrusion/drying

-Iron High Speed: Products turn black and yellow, affecting electrical performance and appearance

-High impurities: worn equipment, blocked nets, broken wires

5. How to choose between active calcium and regular calcium? -Activated calcium carbonate has undergone surface modification, and the customer asked: Do you want to add money to buy activated calcium?

-It must be active when used in plastics and rubber; Ordinary filling and building materials can use ordinary calcium

二、 Arrival inspection&storage issues

1. How to perform simple self inspection after arrival? -Visual inspection of whiteness, hand feel for thickness, presence of lumps, and odor

-Simple testing of settlement volume and moisture content to determine if it is adulterated or inferior

2. Can calcium carbonate still be used if it gets damp and clumps? -Slight clumping and breaking can be used; Severe moisture can affect dispersion and performance

-Storage must be moisture-proof, rainproof, and ventilated

3. What should we do if the supplier changes ore or batch, and the quality is unstable? -The fluctuation of whiteness and fineness leads to significant fluctuations in customer production

-This is the most headache inducing stable supply issue in procurement

三、 The most common problems in production and use

1. The filling amount cannot be added, and problems arise when added - Plastic: poor plasticization, brittle product, rough surface

-Rubber: difficult mixing, abnormal vulcanization

-Paint: sedimentation, delamination, poor thixotropy

2. Poor dispersion, resulting in particles, pitting, scratches - insufficient fineness, incorrect selection of dispersant, insufficient mixing time

-Even if the active calcium is not properly modified, it will still have poor dispersion

3. The product turns yellow, gray, and lacks whiteness - the original calcium carbonate ore has low whiteness and high iron content

-Pollution and impurities during processing

4. Strong odor and peculiar smell - poor quality of modifiers and coupling agents, and odor precipitation at high temperatures

-Common problems with low-end activated calcium

5. Wear and tear screws, grinding tools, and equipment - high Mohs hardness of calcium carbonate and high sand impurities

-The raw ore from the mine has not been thoroughly washed and sorted

6. The more you use it, the higher the cost. How can you reduce it? -I want to increase the filling ratio, but I'm afraid it will affect the performance

-How to match different grades of calcium carbonate to achieve optimal cost-effectiveness

四、 Cost and supply issues that customers are concerned about

1. Why is there such a big price difference? Do you dare to use cheap calcium? -Low price is mostly due to low whiteness, high impurities, and coarse powder

-Seemingly saving money, but with high scrap rates and significant losses in the later stages, it is actually more expensive

2. How to choose the nearest source of goods when the freight ratio is high? -The cost of heavy goods logistics is crucial, and customers often ask reliable manufacturers nearby

3. How to ensure long-term stable supply? -Small factory kilns shut down, environmental protection restrictions on production, mine rectification, and frequent stockouts

五、 Exclusive issues for customers from different industries

-Plastic industry: specific gravity, impact strength, tensile strength, dispersion, plasticization

-Rubber industry: vulcanization speed, hardness, reinforcement, mixing processability

-Coatings and inks: suspension, coverage, fineness, weather resistance

-Paper industry: retention rate, smoothness, whiteness, and bulk thickness

-Building materials mortar: strength, workability, water retention, cost