Best Practices for Coal Management in Thermic Fluid Heaters

Best Practices for Coal Management in Thermic Fluid Heaters

Thermic fluid heaters are essential for various industrial applications requiring consistent and precise thermal energy transfer. Unlike conventional boilers, these systems use a thermal oil or fluid as the medium to distribute heat without needing high-pressure operation. Among the diverse fuels utilized in thermic fluid heaters, coal remains a cost-effective and widely used option, particularly for industries seeking to balance efficiency and operating costs.

Depending upon the type of fuel and its quantity in stock, storage and handling should be arranged. Effective coal management for thermodynamic fluid heaters is critical to ensuring optimal performance and longevity of the system. From storage and preparation to delivery into the heater unit, each phase of coal handling plays a vital role in efficient combustion and steady thermal energy production. Proper coal processing enhances the heater’s performance and reduces operational issues, environmental impact, and energy wastage.

Coal is utilized as the primary fuel in many thermic fluid heaters due to its abundant availability and high calorific value. When handled appropriately, coal becomes a highly efficient source of energy. This article delves into the key aspects of managing coal in thermic fluid heater systems, handling processes, equipment, and crucial safety measures.

Coal Handling Process for Thermic Fluid Heater

The journey of coal from its storage location to its combustion in a thermic fluid heater involves multiple stages. Understanding these steps is paramount to maintaining smooth operations and maximizing fuel efficiency.

Types of Coal Used for Thermic Fluid Heaters

The type of coal chosen for thermic fluid heaters significantly influences the system’s overall efficiency and performance. Commonly used types include:

Anthracite Coal: Known for its high carbon content and energy density, anthracite is ideal for achieving high combustion efficiency.

Bituminous Coal: This type of coal is preferred for its balanced combustion properties and widespread availability.

Lignite Coal: Though low in calorific value, lignite is economical and used in applications with less demanding energy requirements.

Each type has distinct combustion characteristics, and the choice depends on factors such as availability, cost, and the specific design of the thermic fluid heater.

Steps Involved in Coal Handling

Coal Storage: Proper storage is the foundation of an efficient coal-handling process. Coal is typically stored in silos, bunkers, or open yards, depending on the facility’s infrastructure. Ensuring a moisture-free storage environment is vital, as moisture can reduce the calorific value of the fuel and hinder combustion.

Provide Sufficient Space: In case of a manually operated installation, it is necessary to provide sufficient space in the heater room, for stocking coal required for one shit operation of the Thermic Fluid Heater . It is advisable to build walls of about 1.8 meters in height on two sides and a small wall of about 0.65 meters in front of the coal storing area for retaining the coal. Further to this service coal stock in the Heater Room, it is quite essential to store the coal required for three to four weeks’ operation of the Thermic fluid heater  as close as possible to the room.

Minimize Carpet losses: This will act as a buffer against interruption in the coal supply. Storing coal on unprepared ground causes high “Carpet losses,” i.e. losses due to layers of coal on the ground remaining untouched. About 4%—5% of the coal may have to be written off as initial stockpiling on such sites. This can be avoided by storing coal on a leveled concrete surface. The concrete floor should be capable of carrying vehicles and have self-draining facilities.
While unloading, if the lorries dump the coal haphazardly over the storage area, their whole space may be covered with small heaps. Much of the ground may thus be wasted, and trimming may be needed to fill in the spaces between the heaps and to bring their whole stack to a uniform height.

Trimming The Coal: Also, it is difficult to assess the quantity of coal held in stock when it is dispersed in a large number of irregularly shaped small heaps. In order to enable better utilisation of the storage space and to reduce the frequency of trimming the coal, the stockpile is divided into bays by brick or concrete retaining walls, which are normally about 3 meters apart and about 1.5 meters high. Vehicles can bank into such bays and fill them completely to a height of about 1.4 meters maximum. The length of the retaining wall is usually around 3 meters, and the bays are closed on one side by a retaining wall 1.5 meters high.

A thumb rule, to calculate the storage area required, is to provide 1.3 sq. meters of floor area per tonne of coal laid in a layer 1 meter deep. To this is to be added the space required to maneuver the vehicles when unloading or removing the coal. It is necessary to construct an ash pit in the Heater Room as shown in the drawings I mentioned in the first paragraph. Care is to be taken to see that it is built in such a way that the ash does not mix with the coal. It is also necessary to build an ash storage pit of about 5 meter x 5 meter x 2 meter deep outside the Heater Room. This ash pit can be sized to suit the individual plant’s requirements but generally a pit of dimensions i mentioned above will be quite adequate.

Crushing: The raw coal is subjected to size reduction to achieve the desired granularity. Efficient crushing ensures better combustion by improving the surface area-to-volume ratio, thereby facilitating quicker and more complete fuel burning.

Conveying: Conveyor belts or pneumatic systems transport the processed coal from the storage facility to the feeding point of the thermic fluid heater. Smooth and continuous conveyance minimizes interruptions in fuel supply and contributes to steady heater performance.

Importance of Proper Coal Sizing for Efficient Combustion

The granularity of coal significantly impacts its combustion properties. Oversized coal particles may result in incomplete combustion and reduced efficiency, while excessively fine particles can lead to operational challenges like clogging and excessive ash production. Proper coal sizing balances combustion efficiency and operational smoothness, ensuring maximum thermal energy output.

Equipment Used in Coal Handling for Thermic Fluid Heater

Efficient coal handling requires the use of specialized equipment designed to streamline the process and enhance the heater’s performance.

Storage Silos for Coal Storage

Silos are crucial for storing large quantities of coal in a controlled environment. They protect the coal from external contaminants such as moisture and dust, ensuring consistent fuel quality. Modern silos are equipped with advanced features like automated coal discharge systems, facilitating seamless supply to the next stage of handling.

Crushers for Reducing Coal Size

Crushers are vital for breaking down raw coal into uniform-sized particles suitable for combustion. Common types of crushers include:

Jaw Crushers: These are used for primary crushing. Jaw crushers in coal handling reduce large coal chunks into smaller, manageable sizes. They operate by compressing coal between a fixed and a movable jaw plate. This mechanical pressure breaks the coal into smaller pieces, facilitating easier transport, storage, and further processing in coal preparation plants.

Impact Crushers are suitable for finer size reduction. In coal handling, impact crushers use high-speed impact forces to break coal into smaller pieces. Rotors with hammers or blow bars strike the coal, causing it to shatter upon impact. This method is efficient for producing uniformly sized coal, ideal for combustion or further processing in coal preparation plants.

Roll Crushers: These are Effective for producing uniform coal sizes. Roll crushers in coal handling crush coal between two rotating rollers. As coal passes through the gap, it is compressed and broken into smaller, uniform-sized pieces. This method is effective for reducing coal size with minimal fines generation, making it suitable for preparation and transportation in coal-handling systems.

By ensuring optimal coal sizing, crushers play an integral role in enhancing the efficiency of the thermic fluid heater.

Conveyor Belts for Transferring Coal to the Heater

Conveyor systems transport coal efficiently and reliably from the storage silo to the thermic fluid heater. These systems come in various forms, including belt conveyors, screw conveyors, and chain conveyors, each tailored to specific operational needs. Features like speed control and automated loading/unloading mechanisms ensure a smooth and continuous fuel supply.

Safety Measures in Coal Handling for Thermic Fluid Heater

Handling coal requires strict adherence to safety protocols to prevent accidents and ensure a secure working environment.

Proper Training for Personnel Handling Coal

Personnel involved in coal handling must receive comprehensive training on equipment operation, safety procedures, and emergency protocols. Regular training sessions help workers stay updated on best practices and maintain awareness of potential hazards.

Regular Maintenance of Equipment to Prevent Accidents

Preventive maintenance is essential for keeping coal-handling equipment in optimal condition. Routine inspections, timely repairs, and replacing worn-out components reduce the risk of mechanical failures and accidents. Maintenance schedules should be strictly followed to minimize downtime and enhance overall operational efficiency.

Use of Personal Protective Equipment (PPE) When Working with Coal

Workers handling coal must wear appropriate PPE, including safety helmets, gloves, goggles, and respiratory masks. These protective measures safeguard against injuries, dust inhalation, and exposure to harmful substances.

Conclusion

In summary, coal management for thermic fluid heaters is vital to ensuring efficient and reliable thermal energy generation. Each process step, from selecting the right type of coal to implementing effective handling practices, contributes to the system’s overall performance and longevity. Proper equipment usage, regular maintenance, and adherence to safety protocols further enhance the operational efficiency and safety of the handling process.

Coal’s role in thermodynamic fluid heaters remains indispensable for industries seeking cost-effective and consistent heat production. By prioritizing proper coal handling techniques, facilities can optimize combustion efficiency, reduce environmental impact, and ensure uninterrupted operations.

As technological advancements continue to reshape industrial processes, the future of coal handling systems for thermoelectric heaters holds promising potential. Innovations such as automated monitoring systems, AI-based predictive maintenance, and eco-friendly coal preparation methods are revolutionizing how industries manage coal for thermal energy applications.

Industries must stay abreast of these developments and embrace modern practices to remain competitive and environmentally responsible. By doing so, they can achieve operational excellence while contributing to sustainable energy solutions for a better future.