Chemical plants are unforgiving environments for bulk handling. In the chlor-alkali industry — where chlorine, caustic soda, and related by-products are produced — the conveyed materials are often hot, corrosive, abrasive, or prone to dust explosion. This case study walks through how we designed a complete conveying solution for a boiler-renovation project in this sector.
1. The Engineering Challenge
The project centered on a renovation of a power-boiler system that needed a slag and by-product handling line feeding into the existing chemical process. The duty was demanding on three fronts:
- High temperature: Slag and ash leave the boiler at several hundred degrees. Standard rubber belts and seals fail quickly without the right materials.
- Corrosivity: The chemical atmosphere attacks unprotected steel — structures, fasteners, and valve bodies all need compatible materials.
- Dust & safety: Fine, sometimes combustible dust required controlled transfer points and effective collection to meet safety and environmental limits.
2. System Scope
Tianyi supplied an integrated package rather than isolated machines, so the interfaces were engineered together:
- Receiving & crushing: A heavy-duty crusher reduces oversized slag to a conveyable size, fed by a controlled feeder.
- Conveying: A combination of troughed belt conveyors for long horizontal runs and a bucket elevator for the vertical lift into the silo or process.
- Discharge & diversion: Industrial valves — flap gates and diverters — route material between silos and process lines without manual intervention.
- Dedusting: A central dust collection system at each transfer point keeps the building clean and compliant.
3. Key Design Decisions
3.1 Material compatibility
Where the environment was corrosive, we specified stainless or rubber-lined contact surfaces and hot-dip galvanized structural steel. Fasteners and seals used grades chosen for the chemical atmosphere, not generic hardware.
3.2 Heat management
For the hot slag stream, the first transfer used heat-resistant belt compounds and impact zones lined with refractory or wear plate. Cooling zones and controlled residence time kept belt and bearing temperatures within design limits.
3.3 Valves built for the duty
The diverter and flap gates used metal-to-metal or hardened sealing matched to the abrasive media, with pneumatic actuation tied into the plant DCS. Sizing followed our standard selection logic — bore matched to line velocity, actuation chosen for cycle frequency, and pressure class set above the operating envelope.
| Subsystem | Design focus | Why it matters here |
|---|---|---|
| Crusher & feeder | Controlled, sized feed | Protects downstream belts from shock loads |
| Belt conveyor | Heat-resistant belt, sealed rollers | Survives hot, dusty transfer |
| Bucket elevator | High-lift, monitored belt | Vertical transport into process silos |
| Valves | Hardened seal, pneumatic | Reliable routing, low manual labor |
| Dust collector | Point extraction | Safety + environmental compliance |
3.4 Safety & monitoring
Belt misalignment switches, speed monitors, bearing-temperature sensors, and dust-explosion venting (where applicable) were wired into the control system with automatic trip logic — not just alarms.
4. Outcomes
The renovated line achieved stable, continuous handling of boiler slag and by-products with minimized manual intervention and a clean, compliant transfer environment. Because the package was engineered as one system, commissioning was faster and spare-part management simpler — critical spares (idlers, scraper blades, valve seals, bearings) were standardized and stocked locally.
Frequently Asked Questions
What equipment is used in a chlor-alkali conveying system?
Typically a crusher and feeder for sized feed, belt conveyors for horizontal runs, a bucket elevator for vertical lift, industrial valves for diversion, and a dust collector at transfer points.
How do you handle hot, corrosive material in conveying?
We specify heat-resistant belts and refractory-lined impact zones for high temperature, and stainless or rubber-lined contact surfaces plus galvanized structure for corrosivity.
Can Tianyi engineer a complete chemical-plant conveying line?
Yes. We supply an integrated package: receiving, crushing, conveying, lifting, diversion, and dedusting engineered as one system, not isolated machines.
What safety features are needed for chemical-duty conveyors?
Misalignment and speed switches, bearing-temperature sensors, dust-explosion venting where applicable, and automatic trip logic wired into the plant control system.
How does Tianyi control dust in chemical plants?
Point-of-source extraction at each transfer point plus a central dust collection system keeps the building clean and within environmental limits.
Designing a Chemical-Plant Conveying Line?
Send us your material properties (temperature, corrosivity, abrasiveness, particle size) and process flow. We'll engineer a system matched to your duty — not a generic catalog build.
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