Shanxi 200 Tons/Hour Iron Ore Fine Crushing Line: "Screening Before Crushing" Process Saves Clients 3% in Beneficiation Recovery
Project Overview: The core challenge in iron ore processing is not "how well it can be crushed," but "preventing over-crushing." Located in Shanxi, this project addresses the high-silicon, high-abrasion characteristics of local magnetite. We abandoned the traditional, extensive crushing method and introduced a precise "screening before crushing" process. By innovatively placing a linear screen between the coarse and fine crushing stages, we successfully prevented ineffective crushing, achieving a stable production capacity of 200 tons/hour and significantly improving the client's iron concentrate recovery rate and overall economic benefits.
Project Core Parameters
Indicator Dimensions
Detailed Parameters
Project Location
Shanxi, China
Processing Raw Material
Iron ore (mainly magnetite, with associated quartz veins, Mohs hardness 5.5–6.5, extremely abrasive)
Design Capacity
200 t/h
Target Product
≤12 mm high-quality fine material (directly fed into the mill/sintering process)
Main Equipment Configuration
Jaw crusher + linear screen + CS420 single-cylinder cone crusher + HP300 multi-cylinder cone crusher
Process Highlights
Pre-screening (screening before crushing): effectively prevents iron ore from becoming muddy and being over-crushed
Customer Pain Points: The invisible "sludge" consumes real gold and silver
Iron ore processing is completely different from building aggregate. Aggregates are afraid of being "not crushed cleanly" (poor particle shape), while iron ore is most afraid of being "over-crushed." Once iron ore becomes muddy, the recovery rate of fine-grained minerals in subsequent magnetic separation and flotation stages will plummet. If an extra 3% of -0.074 mm slime is produced from one ton of ore, the beneficiation recovery rate can drop by 5 to 8 percentage points, directly leading to a decrease in iron concentrate grade and a significant loss of profits.
The fatal flaw in the existing production line: The customer's original production line used a "jaw crusher to cone crusher" model. 30%–40% of the already qualified small particles from the jaw crusher output were forcibly fed into the cone crusher for "re-crushing." This not only wasted electricity but also artificially created a large amount of over-crushed slime. The -200 mesh content in the finished product remained high, and the beneficiation workshop frequently reported drastic fluctuations in the recovery rate, severely restricting the company's profitability.
The customer's core demand was extremely clear: to achieve precise crushing—crushing only what needs to be crushed, leaving no qualified particles broken—while maintaining a capacity of 200 tons/hour.
Core Process Restructuring: A Linear Screen Eliminates Ineffective Crushing
Focusing on the ultimate goal of "preventing over-crushing and improving recovery rate," we redesigned the entire material flow of the production line. A linear screen is precisely positioned between the jaw crusher and the CS420 single-cylinder cone crusher, creating a value watershed for the entire production line.
Innovative Process Path:
Iron ore raw material (600–800 mm) → Jaw crusher coarse crushing (≤150 mm) → Linear screen pre-screening → Oversize coarse material enters CS420 medium crushing / Undersize fine material bypasses directly into the fine material tank → HP300 fine crushing → Unified output ≤12 mm fine finished product.
The Business Logic of Pre-screening: Traditional processes essentially "pay for excessive crushing," while the addition of a linear screen achieves triple value preservation:
Cutting off ineffective crushing and releasing cone crusher capacity: Fine material passing through the screen is directly bypassed, eliminating approximately 30% of the ineffective load on the CS420 cone crusher, significantly improving the effective operating rate of the core equipment.
Preventing mud formation at the source and preserving iron content: Standard particles are spared secondary compression by the cone crusher, reducing the mud formation rate of the finished product (-200 mesh) from a precipitous drop of 12%–15% on the old line to a stable and controllable level below 6%.
Eliminating wear culprits and extending equipment life: Fine powder acts as an "abrasive" within the crushing chamber; pre-screening removes fine powder, resulting in more even wear on the CS420's liners, significantly reducing consumable costs.
Two-Stage Cone Crusher Synergy: CS420's High Quantity and HP300's High Quality
Faced with high-silica, highly abrasive iron ore, we've implemented a balanced approach to cone crusher beneficiation, combining high output with high quality:
CS420 Single-Cylinder Cone Crusher (Medium Crusher Core): With its large throughput and concentrated crushing force, it easily handles coarse material from linear screens. The hydraulically automatic discharge port adjustment system eliminates the need for manual intervention during material fluctuations, effortlessly achieving a single-machine throughput of 200 t/h, completely eliminating the bottleneck in medium crushing.
HP300 Multi-Cylinder Cone Crusher (Fine Crusher Gatekeeper): Utilizing the principle of layered crushing, the material is subjected to uniform compression at multiple points, resulting in extremely low fine powder content. Its constant discharge port control system ignores liner wear, consistently and precisely controlling the discharge particle size to ensure 100% of the finished product falls within the ≤12 mm fine material range.
Four Core Business Values Delivered to Clients
After the project went into operation, it not only solved technical pain points but also directly translated into impressive data on the client's financial statements:
Value 1: Recovery Rate Increased by 3%, Significantly Increasing Iron Concentrate Production
This is the project's biggest profit growth driver. Thanks to the "pre-screening + lamination crushing" process, the -200 mesh mudification rate was significantly reduced, and the measured iron concentrate recovery rate in the beneficiation workshop increased by approximately 3 percentage points. For a beneficiation plant with an annual output of hundreds of thousands of tons, this is equivalent to recovering thousands of tons of high-grade concentrate annually, directly creating a huge increase in revenue.
Value 2: Reduced Energy and Material Consumption, Cutting Operating Costs
The linear screen pre-diverts 30% of the qualified fine material, meaning the CS420 performs 60 tons less useless work per hour, saving 15-20 kWh of electricity per hour. Simultaneously, the removal of fine powder combined with the multi-cylinder cone lamination technology extends the CS420 liner replacement cycle by approximately 30%, and the HP300 liner experiences no uneven wear. Extending the lining replacement cycle essentially grants the concentrator more continuous production time.
Value Three: Practicing "More Crushing, Less Grinding," Fully Empowering Downstream Operations
The ironclad rule of the mining industry: "One millimeter more crushing, one hour more grinding." The HP300 multi-cylinder cone mill outputs extremely stable fine particle size (uniformly distributed within the ≤12 mm range), providing perfect feed conditions for the ball mill. After commissioning, the total energy consumption curve for crushing and grinding in the customer's concentrator workshop showed a significant downward shift, and the overall grinding efficiency jumped dramatically.
Value Four: Extremely Stable Production Under All Operating Conditions, Saying Goodbye to Unplanned Downtime
Production in concentrators must be continuous. Once the crushing end stops, the losses caused by the downstream ball mill running idle are incalculable. This production line, through reasonable process margin design and equipment performance matching, achieves a continuous operating output of 200–210 t/h, with monthly unplanned downtime strictly controlled to within 8 hours.
Conclusion: The essence of iron ore processing lies in the philosophy of "knowing when to stop" in crushing. The true value of this solution lies not only in the high efficiency of the cone crusher, but also in the linear screen that intercepts ineffective crushing—it maintains the grade of the iron ore and reduces unnecessary consumption. From previously worrying at the end of the month about "why the recovery rate dropped" to now being confident that "this month is stable," the stability of the production line is the greatest commercial value we deliver to our mining clients.
