POLYGON MACHINE
BAG CEMENT SILO CEMENT
BAG SYSTEMS
Concrete plants typically store cement in large welded or bolted silos. Polygonmach, a major concrete equipment manufacturer, offers an alternative Bag Cement Silo (or “Cement Bag System”) concept: cement arrives on site in pre-packed bags which are stacked or fed into a small discharge hopper. Unlike traditional steel silos, this system is designed for projects with limited space and infrequent demand. Each pre-filled bag is sealed at the factory, reducing moisture contamination in transit. Polygon Machine notes that bag silos are “ideal for small-sized projects or sites with space restrictions”. (The tradeoff is that unloading many bags can be labor-intensive, and empty bags must be handled or discarded.)
Why choose Polygon Machine?
Polygon Machine delivers certified quality (TSE & ISO 9001), global expertise, and durable solutions from 30 m³/h to 240+ m³/h. Polygonmachine is a trusted partner in both compact and large-scale projects.
What cement silo types are available?
Stationary, mobile, and horizontal cement silos—plus cement feeders, filters, and safety systems. Every unit is customizable to match your storage, capacity, and operational requirements.
How is long-term support handled?
Polygon Machine ensures fast setup, training, and after-sales service, minimizing downtime. All plants include modern automation and safety features for easy, efficient use.
OVERVIEW AND SPACE EFFIENCY
In contrast, bulk cement silos are large, fixed installations (often 50–500+ ton capacity) used in most large plants. They are filled by pneumatic trucks and discharge cement via augers or blowers. Bulk silos keep cement dry and allow continuous supply for high-volume batching. However, conventional bulk storage has drawbacks: cement dust is generated during filling/handling and can “cause harm to human health and the environment”. One industry review notes that exposed bulk cement can agglomerate and produce “a lot of dust” during operations. New steel silos mitigate this with sealed vents and filters, but concrete or rudimentary bag storage can suffer 3–5% storage losses and pollution. In practice, traditional bulk silos require heavy foundations, cranes for assembly, and large footprints.
Bulk silos are tall steel cylinders (often requiring 5–10 m of height and a wide base), plus room for delivery trucks. By contrast, bag-storage systems use compact hoppers or small silos. For example, a 3 m³ bag-feed silo (≈4 t of cement) can measure only ~2.9×1.6 ×1.8 m. Polygonmach highlights that its bag systems “fit where shipping in bulk is impractical” (e.g. urban or constrained sites). In tight spaces, stacking bags or using a small modular hopper often requires much less area than a full-size bulk silo. (However, some analyses observe that storing many bags can itself “occupy space” and incur packaging bulk.)
What are the main characteristics of bulk cement silos?
Bulk cement silos are large, fixed installations, typically ranging from 50 to over 500 tons in capacity, and are commonly used in large concrete plants. They are filled by pneumatic trucks and discharge cement through augers or blowers. These silos keep cement dry and allow for a continuous supply to support high-volume batching operations. However, their installation requires heavy foundations, cranes for assembly, and a large footprint.
What are the disadvantages of bulk cement silos?
A key drawback of bulk silos is the generation of dust during filling and handling, which can harm both human health and the environment. Exposed bulk cement may clump and release significant amounts of dust. Basic concrete or bag storage methods can experience 3–5% material losses due to dust and pollution. While modern steel silos mitigate this with sealed vents and filters, the setup remains costly and space-intensive.
What advantages do bag cement silo systems offer compared to bulk silos?
Bag cement silo systems are designed for smaller-scale projects or areas with limited space. Cement arrives pre-packed in bags and is fed into a compact hopper or small silo, eliminating the need for large, fixed structures. For example, a 3 m³ bag-feed silo (holding approximately 4 tons) can measure as small as 2.9 × 1.6 × 1.8 m. This compact design is ideal for urban or space-constrained sites where shipping and storing bulk cement is impractical.
How do space requirements differ between bulk and bag cement silos?
Bulk silos are tall steel cylinders, often requiring 5–10 m of vertical clearance plus a wide base and extra space for delivery trucks. In contrast, bag-storage systems use much smaller hoppers or modular silos, requiring significantly less area. While stacking many cement bags can occupy some space, it is still far less demanding compared to the footprint and infrastructure needed for bulk silos.
AUTOMATION & OPERATION
Bulk silos integrate with automated batching: vacuum fill tubes offload trucked cement into the silo, and controlled augers or air-pump feeders meter cement into the mixer. This reduces manual labor. Bag-fed systems range from simple to complex: the simplest is a manually loaded hopper with an internal bag breaker and screw conveyor. This is inexpensive but “discharges much dust” if unfiltered. More advanced setups add conveyors and pneumatic feeders: bags are tipped onto a conveyor to a machine that rips them open, then a screw auger and blower transfer the powder into a small local silo. Such automated bag-handling rigs greatly reduce manual work and emissions (noted as “high efficiency and environment friendly” in vendor data). In practice, bulk systems still offer greater throughput with minimal interruption once installed, but modern bag-feed modules can approximate that for small-scale use.
DUST CONTROL
Bulk Silos
In a bulk silo, incoming and outgoing flows are passed through dust collectors or filters, so exposure is minimal.
Bag Hoppers
By contrast, uncaptured bag dumping creates high dust levels.
The simplest bag hoppers literally “dump the cement in powder form” into an open screw, so without added filtration they let dust escape.
Adding a sealed bag breaker with negative-pressure venting or a pulse-jet filter greatly improves this.
Modern Systems
Many bag-feed systems now include bag-opening chambers and vent filters to catch dust before it leaves the hopper (avoiding local nuisance or regulatory issues).
In general, any system must address particulate control – one report points out that conventional methods cause “serious environmental pollution” when unfiltered.
Both bulk silos and modern bag-silos can be designed with tight controls to meet Europe/US safety standards.
INSTALLATION & MOBILITY
Setup
Installing a bulk silo is a big project: foundations must be poured, the silo sections assembled (often by crane), and utility hookups made. By contrast, bag-silo units are usually delivered as compact welded hoppers on legs or wheels. For example, one 3 m³ bag silo is “movable… no need of foundation” and simply picked into place with a forklift.
Polygon Machine’s mobile silo variant even mounts the tank on wheels or a trailer, so it can be towed between sites. The company notes that a mobile cement silo on wheels “can be moved from one project to the other, [so] time and money are saved”.
This mobility suits temporary road or utility projects: silos are deployed where needed and retrieved after use, avoiding permanent structures. In summary, bag-silo systems offer much faster setup for small plants, while bulk silos suit long-term installations.
Use in Small-to-Medium Jobs
In practice, bag-silo solutions shine in the kinds of small-to-medium jobs typical in Europe and the US: urban infill, remote work sites, or rental plants.
For example, a UK contractor needing frequent small batches adopted a compact mobile mix plant with a single cement hopper.
This replaced endless manual bag handling. The new setup (including a 5 m³ silo) enabled on-demand, 5-minute batches that were “controllable” and “waste-free”, greatly boosting flexibility and speed.
Environmental and International Applications
In the US, tight environmental rules favor enclosed storage: one ReadyMixer case study even advertises that switching from bags to a small on-site silo can “avoid costly EPA fines” by cutting dust emissions.
Polygon Machine itself showcases installations such as a 45 m³/h compact plant in Florida and big-bag unloading systems in Greece, underlining how bag-silo equipment is used internationally.
As demand grows for flexible, low-volume production, these space- and labor-saving systems are increasingly attractive where a full-size bulk silo is impractical.
Parameter – Bag Cement Silo System (Typical)
| Parameter | Description |
|---|---|
| Storage Capacity | 3–10 tons of cement (3–8 m³); e.g., a 3 m³ hopper ≈ 4 t |
| Supported Bag Sizes | Standard cement bags (50 kg, 100 kg) and jumbo bags (1 t or 1.5 t) |
| Discharge System | Bottom screw conveyor with vibrator motor (e.g., 4 kW) and outlet valve |
| Bag Opening | Manual or automatic bag-breaking; integrated cutter knife for opening bags |
| Dimensions (L×W×H) | ~2.9 × 1.6 × 1.8 m (for 3 m³ unit); custom models for larger capacities |
| Empty Weight | ~3000 kg (for 4 t silo) |
| Mobility | Forklift pockets or wheeled chassis; no concrete foundation required |
| Controls/Automation | Optional level sensors, weigh scales, or PLC; manual or semi-automatic feeding |
| Dust Control | Built-in vent filters or pulse-jet dust collector (often paired with bag breaker) |
| Use Case | Temporary/movable storage on small sites (easy batch feed, e.g., small ready-mix plants) |