A coal-fired power plant moves three critical bulk streams: coal into the boiler, ash and slag out of the boiler, and sorbents into the flue-gas cleaning system. Each stream has different temperatures, particle sizes, abrasion levels, and sealing requirements. This guide explains how to select the right conveyor, feeder, elevator, and auxiliary equipment for each duty — based on Tianyi Machinery's power plant project experience.

In this article

1. The three material flows in a coal plant 2. Coal handling and boiler feeding 3. Slag and ash removal systems 4. FGD and flue-gas treatment conveying 5. Explosion-proof and dust-sealed designs 6. Auxiliary and general-purpose equipment 7. Selection criteria by duty 8. Power plant project references Frequently asked questions

1. The Three Material Flows in a Coal Plant

Before selecting any machine, map the plant by flow. The three streams are independent but must interface cleanly:

The wrong machine in any one stream creates dust, blockages, wear, or safety incidents. The sections below match equipment to each flow.

2. Coal Handling and Boiler Feeding

Coal is abrasive, dusty, combustible, and often wet. A complete coal handling system usually includes the following equipment:

For CFB boilers: circulating fluidized bed units commonly use an en-masse chain conveyor as the coal feed path from the bunker to the boiler. The enclosed design keeps coal dust contained and supports multiple feed points.

3. Slag and Ash Removal Systems

After combustion, ash and slag are hot, abrasive, and dusty. A reliable removal line protects boiler availability and environmental compliance. The typical Tianyi solution is the "en-masse chain conveyor + bucket elevator + enclosed slag bin" combination.

EquipmentRole in slag/ash handlingKey requirement
En-masse chain conveyorCollect bottom ash/slag from the boiler and transport it horizontally or on a slight inclineHeat resistance, abrasion liners, sealed casing
Bucket elevatorLift ash/slag from basement level to storage silosHigh-temperature buckets, anti-wear chain/belt
Chain bucket conveyorContinuous slag removal with integral liftingRobust chain and buckets for hot slag
Enclosed slag/ash binIntermediate or final storageGas-tight, with level gauges, aeration, and discharge valves

Support components include bin wall vibrators, dust collectors, hoists, manual/electric gates, dry ash bulk loaders, vacuum/pressure relief valves, and continuous level meters. These items ensure smooth discharge and a dust-free work area.

Large coal handling silo and structural steelwork at a thermal power plant
Figure 1. Coal-fired power plant bulk handling installation: enclosed storage and conveyor support structure.

4. FGD and Flue-Gas Treatment Conveying

Modern plants must remove sulfur oxides and particulates. This requires another set of conveyors:

Tianyi has particular experience in limestone receiving systems and dry-FGD limestone powder conveying, where a fully sealed mechanical line is preferred over pneumatic transport for large, continuous flows.

5. Explosion-Proof and Dust-Sealed Designs

Coal dust is combustible, and some streams contain flammable gases. Standard open conveyors are not acceptable in many zones of a power plant. Tianyi offers two specialized en-masse conveyor families:

Selection tip: specify gas-tight or explosion-proof construction whenever the material is combustible dust, the surrounding atmosphere may contain flammable gas, or local codes require ATEX/NFPA/GB compliance. The mechanical design must be confirmed before motor and control specifications are finalized.

6. Auxiliary and General-Purpose Equipment

Several other Tianyi machines are commonly used across coal plant material streams:

Belt conveyor and storage silos at a thermal power project
Figure 2. Belt conveyor feeding storage silos in a thermal power project: continuous, high-capacity bulk transport.

7. Selection Criteria by Duty

DutyRecommended equipmentKey selection factors
Raw coal receiving / transferBelt conveyor TD75 / DTII / DJCapacity, length, lump size, incline, dust sealing
Coal bunker to boiler / pulverizerTMSD en-masse coal feederFeed rate accuracy, speed range, metering method, CFB vs. pulverized-coal boiler
Coal / coke with explosive dustTMSF gas-tight en-masse conveyorATEX/NFPA/GB rating, gas sealing, explosion venting
High-dust powder under positive pressureTMSFc dust-sealed powder conveyorCasing pressure rating, shaft seal type, access for cleaning
Bottom ash / slag removalEn-masse conveyor + bucket elevatorTemperature, abrasiveness, lift height, silo interface
Limestone / gypsum in FGDBelt conveyor or en-masse conveyorMoisture, capacity, sealing, continuous vs. batch
Heavy lumps / severe impactApron feederImpact load, abrasion, capacity up to 3,000 t/h

8. Power Plant Project References

Tianyi Machinery has supplied conveying and auxiliary equipment to multiple thermal power projects, including:

These projects used combinations of belt conveyors, en-masse chain conveyors, bucket elevators, dust collectors, feeders, crushers, screens, and steel silos — confirming the suitability of the equipment combinations described above.

Frequently Asked Questions

What is the best conveyor for coal handling in a power plant?

Belt conveyors are best for high-capacity, long-distance raw coal transport. For metered boiler feeding from a coal bunker, the TMSD en-masse coal feeder is preferred because it is enclosed, low-speed, and supports precise volumetric or gravimetric metering.

How is bottom ash and slag removed from a coal-fired boiler?

Bottom ash and slag are usually removed by an en-masse chain conveyor at the boiler base, then lifted by a bucket elevator to an enclosed slag bin. The system is sealed and often includes dust collection, level monitoring, and dry ash loading equipment.

When should I choose a gas-tight or explosion-proof conveyor?

Specify gas-tight or explosion-proof construction when handling combustible dust such as coal or petroleum coke, when the surrounding atmosphere may contain flammable gas, or when local codes require ATEX, NFPA, or GB explosion protection. Tianyi's TMSF series is designed for these conditions.

What equipment is used for limestone in FGD systems?

Wet FGD systems typically use belt conveyors for limestone receiving and en-masse or screw conveyors for limestone powder in dry FGD. Bucket elevators and belt conveyors handle dewatered gypsum. Sealing and dust control are critical because limestone powder is fine and can create dust.

How do I size a coal feeder for a CFB boiler?

Start from the boiler's maximum continuous rating and coal heat value to calculate the required coal mass flow in t/h. Add a 15–20% margin, then select a feeder whose volumetric or gravimetric capacity covers that rate at the coal's bulk density. The feeder must also match the bunker outlet geometry and the boiler's feed point layout.

Need a Power Plant Conveying System Design?

Send us your coal type, ash content, boiler type, capacity, and layout. Our engineering team will propose a complete coal handling, ash removal, or FGD conveying system — including conveyors, feeders, elevators, dust collectors, and silos — sized for your thermal power project.

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