(46 products available)
A boiler slag grate is a type of furnace bottom that helps in the efficient burning of coal in steam boilers. Coal is burned to produce steam, which is then used to power trains, run turbines, or for any other applications requiring steam power. The steam boilers are called steam boilers because they produce steam. However, the process does not end there. The steam produced must be contained, and that is what a steam boiler does. But back to the topic at hand, a boiler steam grate is an essential part of a coal-burning steam boiler used mainly in the power generation industry. The grate is a platform that allows the ash and slag produced from burning coal to fall away from the furnace, keeping the firebox clean and uncluttered. The cutout sections of the grate that can be removed allow operators to inspect the firebox and remove any large pieces of unburnt coal or blockages. Different types of boiler slag grates include:
Walking Beam Grate
A walking beam grate uses two beams that move up and down to make the grate walk. The two beams make the grate walk by moving one beam at a time while the other is stationary. This motion is then transferred to the grate, making it walk. This type of grate is mainly used in large boilers.
Bar Grate
A bar grate is one of the simplest types of boiler slag grate. It consists of a series of bars arranged in a square or rectangular pattern. The bars are set parallel to each other, leaving spaces between them. The spaces between the bars allow ash and slag to fall through. They also provide good air circulation, which helps to keep the fire burning hot and efficiently.
Dumping Grate
This type of grate can tilt and move in different directions. The dumping grate can be tilted and moved in various directions to dump the ash and slag that have accumulated on the furnace's bottom. The dumping grate is mostly used for smaller boilers.
Chain Grate
The chain grate differs from the other two types because it uses chains to move the ash and slag instead of bars or beams. The chain grate consists of linked metal chains that continuously move in a loop. As the chains move, they pull the ash and slag toward the furnace's end, where they can be removed. The chain grate is primarily used in industrial boilers because it requires less labor.
Slag and ash from the combustion process are two byproducts that are produced when fuel is burned in a boiler. The ash contains leftover material from the fuel, while the slag is a glass-like substance formed from certain impurities in the fuel. Both need to be removed from the system to prevent damage to the boiler and other components. A boiler slag grate serves this purpose.
Boiler slag grates are large platforms or meshes that ash and slag fall onto after being blown off the furnace walls. They are positioned below the furnace chamber. The two byproducts then slowly move down the grate through the gaps created by the bars or beams as they cool and solidify.
Once cooled, maintenance crews can easily remove the ash and slag from the furnace grate area for disposal or recycling. This not only protects the boiler from damage but also helps recover valuable byproducts like minerals that can be used in construction.
Features of boiler slag grates:
Every industry has its own way of using products, and the same goes for the energy industry when it comes to boiler slag grates. Looking at the various industry applications gives buyers insight into market demand.
Power plants:
Grates are common in large and medium-sized coal-fired plants. These plants use a variety of fuels, including biomass, coal, and waste materials. The greats are integral parts of the power-generating boilers. They are designed to handle the ash produced during combustion effectively. The ash is from the burning of fuel to generate heat and steam for electricity production. The great slabs allow the continuous operation of the boiler by minimizing boiler downtime. This is because they facilitate the efficient removal of ash.
Cement and lime kilns:
Grates are used in cement and lime production facilities. Here, they are installed on the rotary kilns. The grates allow the easy and efficient removal of ash and slag from the process. The ash and slag are byproducts of the high-temperature processes that produce clinker and lime. The use of grates in these applications enhances the overall efficiency of the production processes. They ensure that the kilns operate optimally for longer periods. This creates a favorable environment for cement and lime production.
Metal smelting operations:
Slag grates are also found in industrial operations that involve high-temperature metal smelting. For example, the ferrous and nonferrous metal industries. These grates help to remove slag from the furnaces efficiently. The slag is a byproduct of metal smelting and needs to be removed to keep the operation running smoothly.
Large-scale commercial and institutional facilities:
Some large facilities, such as hospitals, universities, and industrial plants, use biomass and waste-to-energy boilers. These boilers come with grate systems that help in the efficient combustion of biomass and waste materials. The great systems produce steam for heating or power generation in a sustainable way. They do this by utilizing organic materials and municipal waste.
When selecting a boiler slag grate, consider the following factors:
Fuel type and composition:
Different fuel types significantly influence ash characteristics and slag formation. For example, coal, biomass, and waste fuels generate distinct ash profiles. Coal varies by region, such as sub-bituminous, PRB, and eastern coals. Each has unique slag and ash properties. Biomass fuels also differ depending on the feedstock. Fuels like wood chips, agricultural residues, and energy crops have different ash melting points and behaviors. Understanding the fuel helps select a grate designed for the specific ash and slag characteristics. Some grates handle volatile, low-ash slags better than others. Analyzing the fuel guides choice of a grate type—fixed, traveling, or reciprocating—best suited to the ashing and slagging properties. This ensures efficient operation despite varying ashing from different fuels.
Boiler design and operating conditions:
Different boiler designs and operating conditions significantly impact the performance and choice of ash and slag removal systems. For example, in a water-cooled furnace, the cooling effect of the water walls allows for higher temperatures and more complete combustion of the fuel. This can lead to more fusion and agglomeration of ash particles into larger slag formations. As a result, a robust removal system is needed to handle this slag. Techniques like mechanical raking or hydraulic removal may be employed. In contrast, a boiler with air-cooled grates may need to prioritize immediate quenching of hot ash to prevent slag formation. Here, effective cooling and fracture of ash particles is critical for efficiency. High-temperature drop boxes or thorough air cooling may be utilized for swift ash processing.
Maintenance requirements
Grates that require high maintenance demand more time and resources from the plant staff, which increases the overall costs of operation. On the contrary, low-maintenance grates are easy to operate and do not require much time or resources, making them cost-effective. However, low maintenance usually means that the parts used are not durable and could easily be damaged. In contrast, highly durable grates may need specialized parts that could be expensive. The balance between low maintenance and high maintenance is important, but one should not choose a grate with high maintenance.
Q1: What is boiler slag?
A1: Boiler slag is a byproduct of burning coal in boilers for electricity generation. It forms from unburned coal, ash, and other materials that melt at high temperatures. Boiler slag can be reused in construction projects, but it must be properly processed and handled.
Q2: What is a boiler grate?
A2: A boiler grate is a framework with bars that coal or biomass fuel is burned on in industrial boilers. The grate allows ash and air to fall through while supporting the fuel as it burns.
Q3: What is a slag grate?
A3: A slag grate is a type of boiler grate used specifically for burning high-ash, non-caking coals or biomass fuels. It has features like water cooling and automatic ash removal to handle the harsh conditions created by these fuels.
Q4: What types of grates are there?
A4: There are three main types of boiler grates: stationary, moving, and underfed grates. Stationary grates are fixed in one position, while moving grates are continuously or periodically moved to allow ash removal. Underfed grates have the fire and air supplied from below the grate.
Q5: What are the two main types of boiler furnaces?
A5: The two main types are water tube boilers and fire tube boilers. Water tube boilers have hot gases passing through tubes filled with water, while in fire tube boilers, hot gases travel through tubes that are inside a water tank.
浙公网安备 33010002000092号
浙B2-20120091-4