Submerged Scraper Conveyors (SSC) System for Bottom Ash Handling

Submerged Scraper Conveyors (SSCs) are a reliable and effective solution for bottom ash handling in coal-fired power plants and waste-to-energy plants. These systems are designed to efficiently remove, transport, and process the bottom ash produced during the combustion process. The unique submerged design helps cool the ash, suppress dust, and prevent clogging or wear in the system, making it one of the preferred options for managing bottom ash.

Key Features of Submerged Scraper Conveyors (SSC)

1. Water-Submerged System:
   • SSCs operate in water-filled troughs, keeping the ash submerged as it moves along the conveyor. The water helps cool the ash, suppress dust emissions, and protects the system components from high temperatures.
2. Scraper Mechanism:
   • The scraper blades are attached to a chain that moves along the trough. These scrapers lift and transport the ash through the system, scraping it off the trough’s bottom and pushing it forward to the discharge point.
3. Efficient Ash Transport:
   • SSCs are designed for continuous operation, ensuring that bottom ash is efficiently transported from the boiler or combustion chamber to the designated disposal or storage area. The scraper mechanism is particularly effective in moving dense and sticky ash, preventing blockages.
4. Corrosion and Abrasion Resistance:
   • Given the harsh operating environment (high temperatures, water, and abrasive ash), SSCs are made from corrosion-resistant materials (such as stainless steel or other alloys) to ensure long-lasting performance with minimal maintenance.
5. Dust-Free Operation:
   • By keeping the ash submerged in water, the system eliminates airborne ash dust, providing a safer working environment and minimizing environmental impact.
6. Compact and Flexible Design:
   • The SSC system is adaptable to a variety of plant layouts, whether horizontal or inclined, and can transport ash over varying distances and elevations.

How Submerged Scraper Conveyors Work

1. Ash Collection:
   • Bottom ash is discharged from the boiler or incinerator and flows into the submerged scraper conveyor system. The ash is typically hot and needs to be cooled quickly to prevent risks of fire or excessive wear on the system.
2. Submerged Ash Transport:
   • The bottom ash flows into the water-filled trough where the scraper blades, attached to a chain, move along the trough to scrape and transport the ash to the discharge area. The water in the trough acts as both a cooling agent and a dust suppressant, preventing dust from becoming airborne.
3. Scraping and Moving Ash:
   • As the scraper blades move through the trough, they scrape the bottom ash and push it toward the discharge point. The continuous motion of the scraper chain ensures that ash is efficiently transported without excessive buildup or blockage.
4. Discharge of Ash:
   • At the end of the conveyor, the ash is discharged into a cooling pit, storage hopper, or conveyor to further processing. The system is designed for efficient ash removal to ensure continuous plant operation.
5. Water Circulation System:
   • The water in the trough is continuously circulated to maintain the cooling effect. The water also helps keep the ash submerged and prevents sediment buildup in the trough. The circulation system ensures consistent cooling and transport.

Advantages of Submerged Scraper Conveyors for Bottom Ash Handling

1. Dust-Free and Safe Operation:
   • The submerged design completely suppresses ash dust, which is a major health and safety concern in power plants. This also reduces the environmental impact by limiting the amount of particulate matter released into the air.
2. Efficient Cooling of Ash:
   • As the bottom ash moves through the submerged conveyor, it is cooled by the water in the trough, ensuring that high-temperature ash does not cause damage to conveyor components.
3. Handling of Dense and Sticky Ash:
   • The scraper blades are effective in handling bottom ash that may be dense, sticky, or clumped together, ensuring smooth movement through the system without blockages.
4. Durability and Low Maintenance:
   • The use of high-quality materials like stainless steel and the water-cooled design help extend the lifespan of the system. SSCs are built to withstand the abrasive nature of the bottom ash, reducing the frequency of repairs and the cost of maintenance.
5. Continuous and Reliable Operation:
   • SSC systems are designed for continuous, 24/7 operation, ensuring that ash is constantly removed and transported without delays, which is crucial for maintaining plant efficiency.
6. Environmental Compliance:
   • The system complies with stringent environmental regulations by controlling dust emissions, thus meeting air quality standards and minimizing the environmental footprint of ash handling processes.
7. Compact and Space-Saving:
   • SSCs can be integrated into various plant layouts and configurations, saving space while providing an efficient solution for bottom ash transport and handling.

Components of a Submerged Scraper Conveyor (SSC) System

1. Submerged Trough:
   • The trough is filled with water and serves as the path for transporting the ash. The trough provides cooling and dust suppression for the ash while it moves along the system.
2. Scraper Mechanism:
   • The scraper blades are attached to a chain that moves along the submerged trough. The scrapers scrape the ash from the bottom and transport it toward the discharge point.
3. Chain and Drive System:
   • The chain is driven by a motorized drive system, which ensures continuous movement of the scraper blades and ash. The drive system is designed for durability and reliability, ensuring uninterrupted operation.
4. Water Circulation System:
   • A water circulation system is included to continuously circulate the water within the trough, preventing sediment buildup and maintaining the cooling effect for the ash.
5. Discharge Mechanism:
   • At the end of the conveyor, the ash is discharged into a storage area or further transport system. The discharge mechanism ensures that the ash is moved quickly and efficiently to its next destination.
6. Inspection and Maintenance Ports:
   • These ports allow for routine inspection and maintenance of the system, ensuring that all components, including the scrapers, chain, and drive system, remain in optimal working condition.

Applications of Submerged Scraper Conveyors

1. Coal-Fired Power Plants:
   • Submerged scraper conveyors are used to handle the bottom ash produced from the combustion of coal. The system efficiently transports the ash from the combustion chamber to storage or disposal areas.
2. Waste-to-Energy Plants:
   • In these facilities, SSCs handle the bottom ash generated from the incineration of municipal solid waste, ensuring safe and efficient ash transport and disposal.
3. Cement Production:
   • The bottom ash produced in cement plants (often from the combustion of waste materials in rotary kilns) can be efficiently transported and processed using submerged scraper conveyors.
4. Metallurgical Plants:
   • Steel mills and other metallurgical facilities use SSCs to transport and handle slag or other byproducts generated during metal smelting.
5. Incineration Facilities:
   • Submerged scraper conveyors are used to handle bottom ash in waste incineration plants, ensuring effective removal and safe processing of ash.

Maintenance Considerations for Submerged Scraper Conveyors

1. Water Quality Management:
   • The water in the submerged trough should be monitored regularly for contaminants and debris. Filtration and circulation systems should be maintained to ensure proper flow and cooling.
2. Wear on Scraper Blades and Chain:
   • Regular inspections of the scraper blades and chain are required to prevent wear and ensure efficient ash transport. Scrapers may need to be replaced periodically depending on the abrasiveness of the ash.
3. Drive System Maintenance:
   • The motorized drive system should be checked periodically to ensure proper functionality. Lubrication and adjustment of components like bearings and gears will help prevent premature wear.
4. Water Circulation System:
   • The water circulation system should be inspected for clogs or blockages to ensure continuous water flow. Cleaning and maintaining the pumps and pipes will ensure optimal system performance.
5. Cleaning and Lubrication:
   • Regular cleaning and lubrication of the conveyor components (scrapers, chains, drive system) are necessary to keep the system operating smoothly and efficiently.

Why Choose Submerged Scraper Conveyors for Bottom Ash Handling?

1. Effective Dust Control:
   • By keeping the ash submerged in water, SSCs prevent the release of harmful dust, ensuring a cleaner and safer environment for both workers and the surrounding area.
2. Efficient Ash Cooling and Transport:
   • The water in the trough cools the bottom ash, protecting the conveyor system from high temperatures and ensuring safe transport of the material.
3. Durable and Reliable:
   • The robust construction and materials ensure the system can handle the abrasive nature of bottom ash, requiring minimal maintenance while providing a long service life.
4. Continuous Operation:
   • SSCs provide reliable, continuous operation, ensuring that bottom ash is transported efficiently without disruptions to the plant’s operations.
5. Compliance with Environmental Standards:
   • The system is designed to meet environmental regulations regarding dust emissions, helping plants comply with air quality standards.

If you’d like to dive deeper into the design, installation, or customization of a Submerged Scraper Conveyor for your specific needs, feel free to reach out!

Submerged Scraper Conveyors | SSC system -Ash Handling System in a Power Plant

Submerged Chain Conveyor System For bottom ash handling

Bottom and fly ash handling

• Bottom ash cooling screw
• Ash conveyors
• Bottom ash screen for sand recycling
• Ash container
• Fly ash cooling screw
• Pneumatic conveying systems
• Fly ash silo
• Dry and wet discharging systems

Features of the ash handling system

• Wide capacity range
• Wide cooling range
• High uptime with rugged, proven design

Introduction

FU type scraper conveyor (chain conveyor) is used for horizontal (or slope ≤15°) conveying of powdery, small granular materials. The advantages of this product are: novel structure, reasonable design, raliable running, energy-saving, high efficiency and long service life. Materials are conveyed in sealing box without leak. The conveyor chain slide on the track has less abrasion. This type of device with compact structure, good sealing, rational layout, application convenient maintenance, etc.

This product has been widely used in building materials, chemical, thermal power, mining and other industries due to its big conveying capacity and low energy consumption.

Features

1. Because the scraper conveyor is the use of the material in the friction to drive the material move, therefore, the smaller resistance during operation, low energy consumption, energy saving about 50% less in compared with the screw conveyor.

2. Conveyor chain adopts high strength wear resistant alloy sleeve roller chain plate structure, and after the special technology processing, it has high strength, low friction coefficient, long working life and other characteristics;

3. Wide scope transportation, it should be transport various powder, granular, lump material with high capacity and long distance below 150 ℃.

4. The whole transport process conducted in confined Spaces, sealed safe and reliable, especially suitable for conveying volatile, toxic, corrosive, and special medium, etc.

5. The type scraper conveyor is completed, there are FU200, FU270, FU350, FU410, various types etc. It can customize according to customer’s demand for special.

Technical Parameter

SELECTION & TECHNICAL QUESTIONS

Q1: How do I select the right conveyor model? What information should I provide?

> To recommend the most suitable solution, please provide the following details:

> 1. Material type: What material are you conveying? (e.g., fly ash, wood chips, biomass pellets, bottom ash, etc.)

> 2. Material properties: Particle size, temperature, moisture content, abrasiveness

> 3. Capacity requirement: How many tons per hour (t/h) do you need?

> 4. Installation conditions: Conveying distance, incline angle, space limitations

> 5. Application industry: Which industry is this for? (e.g., waste-to-energy plant, biomass power plant, cement plant)

> You can also email us or contact us via WhatsApp. Our engineers will get back to you within 24 hours.

Q2: What is the difference between screw conveyors and chain conveyors? Which one should I choose?

> Both types have different applications:

> – Screw Conveyors: Best for powdery and small-grain materials (e.g., fly ash, cement powder). Good sealing performance, simple structure, low maintenance cost.

> – Chain Scraper Conveyors: Best for bulky, highly abrasive materials (e.g., bottom ash, municipal solid waste, biomass fragments). Supports multiple inlet and outlet points.

> – Bucket Elevators: Ideal for vertical or steep-incline material lifting.

> If you are not sure, tell us your material and working conditions, and our engineers will help you choose.

Q3: Can your equipment handle high-temperature materials? What is the maximum temperature?

> We can customize equipment according to material temperature:

> – Standard type: 0~80°C, carbon steel

> – Medium temperature type: 80~200°C, thickened wear-resistant liner

> – High temperature type: 200~400°C, special heat-resistant steel, optional cooling jacket

> Please tell us your material temperature, and we will recommend the most suitable material solution.

Q4: Are there any limits on conveying distance and lifting height?

> Standard design range:

> – Screw conveyor: Single section up to 70 meters; multiple sections can be connected for longer distances

> – Chain conveyor: Single machine up to 60 meters

> – Bucket elevator: Lifting height up to 50 meters

> We can also customize for extra-long distances or special angles. Contact us for detailed solutions.

Q5: Do you provide explosion-proof design?

> Yes. For explosive and flammable conditions such as pulverized coal and biomass dust, we offer:

> – Explosion-proof motors (Ex d IIB T4 standard)

> – Reserved openings for explosion vents / rupture discs

> – Fully sealed structure to prevent dust leakage

> Please specify your explosion-proof rating requirements.

CUSTOMIZATION & MANUFACTURING

Q6: Do you support customization? What is the lead time?

> Over 90% of our equipment is customized according to customer working conditions. Standard models take about 90–120days. Special customizations take 120–180 days, depending on configuration complexity.

Q7: What material options do you offer?

> Common materials include:

> – Carbon steel (Q235B): Standard working conditions

> – Wear-resistant steel (NM400/NM500): Highly abrasive materials

> – Stainless steel 304/316L: Food, chemical, corrosion-resistant requirements

> – Bi-metal wear-resistant composite plate: Extreme abrasion conditions

> We will recommend the most cost-effective material solution based on your material properties.

Q8: What certifications do you have?

> We hold the following certifications:

> – ISO 9001:2015 Quality Management System

> – ISO 14001 Environmental Management System

> – ISO 45001 Occupational Health & Safety Management

> – CE Certification (EN 1090 Steel Structure)

> If you need scanned copies of specific certificates, please contact us.

DELIVERY & LOGISTICS

Q9: Which countries do you export to? Do you have export experience?

> Our equipment has been exported to more than 20 countries worldwide, including:

> – Europe: Germany, France, Poland, Turkey, etc.

> – Southeast Asia: Singapore, Thailand, Indonesia, Vietnam, etc.

> – Middle East: Saudi Arabia, UAE, etc.

> – South America**: Brazil, Chile, etc.

> We are familiar with the full export process: packaging, customs declaration, and ocean freight. We can provide FOB, CIF, and other trade terms.

Q10: What is your packaging method? Is it suitable for long-distance ocean shipping?

> Export-standard packaging:

> – Large items / complete machines**: Rust prevention + waterproof film + fumigated solid wood pallet

> – Precision components: Wooden case with shock-absorbing filling

> – Random accessories: Categorized packing with detailed packing list

> All wooden packaging meets IPPC fumigation standards for direct customs clearance.

Q11: What is your minimum order quantity?

> We do not have a strict minimum order quantity. Single-unit orders are welcome. Bulk orders can enjoy more favorable pricing.

INSTALLATION & AFTER-SALES

Q12: Do you provide installation guidance? Do engineers need to come to site?

> We offer two service options:

> 1. Remote guidance: Detailed installation drawings and operation manuals, video guidance for installation (free of charge)

> 2. On-site service: Dispatch engineers to site for installation and commissioning (travel costs are additional)

> Most customers choose remote guidance. Our equipment is designed as a modular structure for easy installation.

Q13: What is the warranty period? What are the wearing parts?

> Standard warranty period is 12 months (from the date of arrival at port).

> Wearing parts list:

> – Chain / screw flights: Approximately 1–3 years, depending on material abrasiveness

> – Liners: Approximately 2–4 years

> – Bearings: Approximately 2–3 years

> We recommend ordering a wearing-parts spare kit together with your first order.

Q14: How do you solve problems during operation?

> We provide 7×24 technical support:>

> – Response within 24 hours for technical issues

> – Remote video troubleshooting guidance

> – Engineer on-site service when necessary

> – Common spare parts in stock for fast delivery

QUOTATION & COOPERATION

**Q15: How can I get a quote? How long does it take?

> Quotation process:

> 1. You provide material parameters, capacity, installation conditions, and other requirements

> 2. Our engineers evaluate and select the appropriate model

> 3. Formal quotation and technical proposal provided within 7 working days

> You can contact us via email, or the online inquiry form.

Q16: What are your payment terms?

> Standard payment terms:

> – 30% advance payment: After contract signing, to start production

> – 70% balance: Before shipment, or against copy of Bill of Lading

For long-term cooperative customers, more flexible payment terms can be negotiated.

Follow these 3 steps to find your ideal conveyor solution

Step 1: Identify Your Material Type

Different materials require different conveyor designs. Tell us what you are conveying:

Step 2: Define Your Working Conditions

Please prepare the following parameters before contacting us:

Step 3: Choose Configuration Options

Based on your answers above, our engineers will recommend:

Material grade — carbon steel / wear-resistant steel / stainless steel

Sealing type — open trough / fully enclosed / gas-tight

Drive system — motor power, gearbox brand, speed range

Auxiliary options — explosion-proof motor, cooling jacket, cleaning device, level sensors

 Not Sure Where to Start?

Send us your basic requirements, and our engineers will design a customized solution for you — completely free.

Email: bootec@bootecgroup.com  Response time: Within 24 hours

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