Three-drum dryer for semi-coal dryer

Three-drum dryer for semi-coal dryer

Structural composition:

• Drum part:

It is composed of three concentric cylinders of different diameters, which are nested and combined, and is the core component. Each cylinder has its specific function. The inner cylinder performs preliminary heat exchange and drying, the middle cylinder further enhances the drying effect, and the outer cylinder plays a role in heat preservation and auxiliary drying.

• Transmission device:

It includes motor, reducer, support wheel, belt, etc. The motor provides power, drives the support wheel to rotate through the reducer, and the friction between the support wheel and the belt causes the cylinder to rotate, ensuring that the material continues to roll and move in the cylinder.

• Feeding device:

It is responsible for conveying the semi-coal to be dried into the dryer, and it is necessary to ensure the stability and uniformity of the feed to avoid blockage or uneven feeding.

• Discharging device:

It is used to discharge the semi-coal after drying, and it must have good sealing to prevent hot gas leakage and dust overflow.

• Heat source system:

It provides heat for the drying process. Common heat sources include coal, natural gas, biomass particles, etc., and the appropriate heat source needs to be selected according to the actual situation.

• Lifting plate device:

Lifting plates and guide plates with different angles and spacings are installed in the cylinder. Their function is to make the semi-coke move along the spiral motion direction under the action of gravity, and maintain sufficient residence time and sufficient dispersion in the cylinder so as to fully exchange heat with the hot air flow.

• Dust removal system:

Collect and treat dust generated during the drying process to reduce pollution to the environment.

• Working principle:

Wet semi-coke enters the inner cylinder through the feeding device, and is continuously picked up and scattered by the lifting plate in the inner cylinder, and conducts preliminary heat exchange with the hot air flow from the combustion chamber to achieve downstream drying and initially remove most of the moisture. Then the semi-coke enters the middle cylinder for countercurrent drying. The material is repeatedly lifted in the middle cylinder to extend the drying time. Finally, the semi-coke falls into the outer cylinder, and is further dried in the outer cylinder and discharged from the discharging device.

Advantages and characteristics of three-drum dryer for semi-coal dryer:

High efficiency and energy saving:

• High thermal efficiency:

The three-drum structure greatly increases the contact area between the material and the hot air flow, making the heat exchange more sufficient. The heat emitted by the inner drum can be partially absorbed and utilized by the middle drum and the outer drum, reducing heat loss. The thermal efficiency can be increased by more than 30%-50% compared with the single-drum dryer, with significant energy-saving effects, reducing energy consumption and production costs.

• Strong fuel adaptability:

It can adapt to a variety of fuels such as coal, oil, and gas. Enterprises can flexibly choose according to local fuel resources and costs.

Good drying effect:

• Even material drying:

The unique drum structure and lifting plate design enable the semi-coal to be evenly dispersed and turned in the dryer, avoiding material accumulation and uneven drying, and ensuring that the moisture content of the semi-coal after drying is uniform and consistent. The moisture content of the dried material can reach less than 0.5%.

• High material quality:

The temperature and heat are evenly distributed during the drying process, and the semi-coal will not deteriorate, discolor, break, etc. due to local overheating, which well guarantees the quality of the semi-coal.

Compact structure:

• Small footprint:

The three-drum dryer has a compact drum structure, and the length of the drum is about one-third of that of the single-drum rotary dryer. The base area is about 65% less than that of the single-drum rotary dryer, which saves a lot of site space and is very suitable for enterprises with limited sites.

• Easy installation:

The overall structure is relatively simple, the installation process is not complicated, and no complex infrastructure and large hoisting equipment are required, which can shorten the installation cycle and reduce the installation cost.

Reliable operation:

• Small equipment wear:

The friction between the semi-coal and the drum and the lifting plate during the drying process is relatively small, which reduces the wear of the equipment and extends the service life of the equipment. In addition, the transmission device of the equipment runs smoothly and has high reliability.

• Low noise:

The friction transmission between the support wheel and the wheel belt is adopted. Compared with the large and small gear transmission, the transmission power is low and the noise during operation is reduced.

• Good environmental performance:

The sealing system adopts advanced sealing methods such as micro-contact technology, which has better sealing effect, reduces dust pollution, and meets environmental protection requirements.

• Flexible operation:

The required final moisture index can be easily adjusted according to user requirements to meet the needs of different users for the drying degree of semi-coal.