Limestone is one of the most widely distributed and abundant non-metallic minerals, primarily composed of Calcium Carbonate (CaCO3). Its compressive strength typically ranges up to 150 MPa, with a Mohs hardness of 3 to 4, classifying it as a medium-to-soft rock with high brittleness.

Processing Strategy: Because limestone has very low abrasiveness on wear parts, ZME’s core design philosophy focuses on “Replacing Pressure with Impact.” We highly recommend using high-performance impact crushers. Compared to cone crushers used for hard rock, the impact crushing process not only delivers a more perfect cubical aggregate shape but also reduces initial capital investment (CAPEX) and operating expenses (OPEX) by approximately 30%.

ZME 350 TPH Limestone Crushing Aggregate Production Flow (Three-Stage Process)

This production line is designed to produce crushed aggregate (split) with precise grading for road base and building construction through an efficient crushing ratio.

Phase 1: Heavy-Duty Primary Crushing

Run-of-mine (ROM) limestone blast muck (input size up to 1000–1200 mm) enters the hopper and is uniformly metered by a ZSW600x130 Series Heavy-Duty Vibrating Feeder. The grizzly bar configuration at the discharge end pre-screens clay fines and dirt, ensuring only clean material enters the crusher. The rock then feeds into a PE1000x1200 Jaw Crusher for primary crushing, rapidly reducing large boulders to a top size below 200 mm.

Phase 2: Secondary Crushing & Shaping

The primary crushed material is transferred via belt conveyor to a PFW1318 Euro-Type Impact Crusher.

• Physical Principle: A high-speed rotor equipped with blow bars delivers a powerful instantaneous impact to the rock.
• Output Quality: The impact crusher provides exceptional shaping capabilities. The resulting aggregates (such as 10–20 mm and 20–30 mm fractions) feature a cubical particle shape with zero internal micro-cracks. The elongated and flaky particle content is strictly controlled below 5%, fully meeting the stringent specifications for highway projects and high-rise construction..

Phase 3: Screening & Closed-Circuit Classification

The material is discharged onto two units of 3YK2460 Vibrating Screens. The oversized material (typically >40 mm) is accurately recirculated back to the impact crusher via a return conveyor for re-crushing. This closed-circuit design guarantees that every grain of the final product complies precisely with the required target specifications, while the accepted fractions are routed to their respective product stockpiles.

ZME 350 TPH Limestone Manufactured Sand Production Flow (Enhanced Four-Stage Process)

With the increasing restrictions on natural sand mining in Indonesia, producing high-standard manufactured sand (M-sand) from limestone has emerged as a significant profit growth driver.

Phase 1 & 2: Primary and Secondary Crushing Pre-treatment

Utilizing the “Jaw Crusher + Impact Crusher” configuration detailed above, the limestone size is reduced to below 40 mm through two stages of crushing. This phase serves as the prerequisite for sand making; a smaller feed size drastically maximizes the throughput efficiency of the sand-making machine.

Phase 3: High-Frequency Sand Making

The properly sized rock is fed into a ZME VSI1140 Vertical Shaft Impact (VSI) Crusher.

• Technological Breakthrough: This equipment features a three-in-one functionality: fine crushing, coarse grinding, and particle shaping. Utilizing a “stone-on-stone” crushing chamber design, materials collide with each other within a high-speed vortex chamber, generating a natural particle size distribution.
• Gradation Control: By adjusting the rotor speed, the proportions of coarse, medium, and fine sand fractions can be precisely regulated.

Phase 4: Washing, Recovery & Eco-Friendly Processing

The finely shaped material undergoes a final screening. For high-end infrastructure projects with stringent limits on silt and dust content, the following systems are deployed:

• Washing Process: An XSD Series Bucket Sand Washer is utilized, where recirculated water thoroughly washes away rock dust and adhering impurities.
• Resource Recovery: The wash wastewater is routed into a Fine Sand Recovery System. This system efficiently captures ultra-fine sand fractions between 0.075–0.16 mm. Beyond increasing total sand yield by 5%–10%, this system purifies the process water for recirculation, fully compliance with green mining standards.

Equipment Configuration List

No.	Equipment	Model	Process Stages	Qty	Main Characteristics	Function
1	Heavy Duty Vibrating Feeder	ZSW600×130	Feeding & Primary Crushing	1 Unit	Direct dump-truck impact resistant, equipped with a grizzly pre-screening feeder	Removes clay/fines before crushing; ensures stable material feed
2	Deep Cavity Jaw Crusher	PE1000×1200	Primary Crushing	1 Unit	Feed opening >1,000 mm, high crushing force	Reduces large limestone to <200 mm for stable downstream feed.
3	European Impact Crusher	PFW1318	Secondary Crushing & Aggregate Shaping	2 Unit	Parallel operation, impact crushing principle	Output up to 350 TPH, excellent cubical shape, and uniform gradation.
4	Circular Vibrating Screen	3YK2460 & 3YK2675	Multi-Stage Screening	2 Unit	Multi-stage screening system with a closed-circuit loop	Separates aggregates according to specifications (1–2, 2–3, etc.) and returns oversize material to the impact crusher.
5	Vertical Shaft Impact Crusher (VSI)	VSI1140	Sand Making & Shaping	1 Unit	“Stone-on-stone” technology, high-speed operation	Produces high-quality manufactured sand with optimized particle shape.
6	Bucket Sand Washer	XSD3016	Sand Washing	1 Unit	Deep washing system	Removes stone powder and clay particles to enhance the quality of construction sand.
7	Fine Sand Recovery System	LZ-300	Material Recovery	1 Unit	High recovery efficiency	Captures lost sand from waste water, increasing total output by approximately 5–10% while reducing environmental pollution.
8	Heavy Duty Belt Conveyor System	B800 & B1000	Material Conveying	1 Set	Custom design tailored to mine topography	Connects the entire process to ensure an automated and stable material flow.
9	PLC Centralized Electric Control System	—	Control System	1 Set	Start-stop interlocking, real-time current monitoring, and overload protection	Ensures safe and stable operation at a high capacity of 350 TPH while improving production management efficiency.

Technical Indicators Summary

• Processing Capacity: 350 Tons Per Hour (TPH)
• Maximum Feed Size: ≤1020 mm
• Final Product Specifications: 0–5 mm (Manufactured Sand), 5–10 mm, 10–20 mm, 20–40 mm (Construction Aggregates)
• Applications: Airport runways, highways, large-scale cement plants, and aggregate supply for high-rise construction.

Why Choose This Configuration?

1. Surplus Capacity Design:

The peak capacity of the PE1000x1200 Jaw Crusher approaches 400 t/h. This surplus ensures the machine handles the 350 t/h target with ease, maintaining continuous stability during long-term, non-stop operations.

2. Parallel Secondary Crusher Layout:

Utilizing two units of the PFW1318 operating in parallel not only boosts the crushing ratio but also provides flexible maintenance windows. If one unit requires servicing, the other unit continues to run, minimizing total production downtime.

3. Tailored Optimization for Limestone:

Capitalizing fully on the soft and brittle characteristics of limestone, this system relies entirely on impact-style equipment (Impact Crusher + VSI). As a result, the cubical particle shape rate of the final product exceeds 95%, making it ideal for high-performance concrete standards.

ZME Solutions: Unique Performance Advantages

1. High Crushing Ratio & Low Power Consumption: By optimizing the rotor’s dynamic balance design specifically for the brittle characteristics of limestone, power consumption per unit of production is reduced by approximately 15%–20% compared to hard-rock production lines.
2. Streamlined Process, Optimized Investment: For clients seeking maximum economic efficiency, ZME offers a alternative “Double Hammer Crusher” process layout. This design reduces belt conveyor requirements by roughly 25% and significantly minimizes the total equipment footprint.
3. Custom Non-Standard Engineering: The technical team designs custom support structures and conveying systems tailored to the actual topography of your site in Indonesia (such as mountainous elevation drops or local water resource distribution), ensuring every dollar invested yields maximum production capacity.
4. Intelligent Monitoring System: An optional centralized PLC control cabinet is available for one-touch operation and remote fault early-warning alerts, effectively preventing costly downtime caused by human operational errors.