Drying process parameters for mosquito coils

Drying process parameters for mosquito coils

（1） Temperature control

The drying temperature of mosquito coils should be precisely controlled between 52 ℃ and 55 ℃. This temperature range has been verified through practice, which can

effectively remove moisture from mosquito coils while ensuring their quality, while avoiding adverse effects on the composition and performance of mosquito coils caused

by excessive temperature.

（2） Changes in weight and moisture content

A mosquito coil has an initial weight of 50 grams and a moisture content of 40%. After drying, the weight became 30 grams. This indicates that a large amount of moisture

is removed during the drying process, thereby achieving a suitable degree of drying for mosquito coils to meet subsequent production and usage requirements.

（3） Tray and drying room parameters

The size of a tray is 900 millimeters long and 450 millimeters wide, and each tray can hold 18 mosquito coils. The spacing between the two layers of trays is set to 40

millimeters, which is conducive to uniform heat distribution and air circulation, ensuring that each mosquito coil can be fully dried. Some fixed drying rooms are 8 meters

long, 4 meters wide, and 2.2 meters high. Such a large drying room can hold more than a thousand trays at a time, and can carry a total weight of more than 1 ton of

mosquito coils. After drying, 830 pounds need to be dehydrated, and the dehydration capacity of the main unit is 150 pounds per hour. According to calculations, the

drying time for one batch is about 6 hours.

Drying assembly line renovation

（1） Background of renovation

The existing drying assembly line has some problems in actual operation, the most important of which is its high complexity. Previous drying systems were mostly built

with bricks, which lacked effective insulation measures. This not only leads to severe heat loss and increases energy consumption, but may also affect the consistency of

drying effect, which cannot meet the large-scale and high-quality production needs.

（2） Transformation steps

The comprehensive insulation renovation of the drying system made of bricks is the first step in the insulation renovation. By adding high-quality insulation materials

such as rock wool board and polyurethane foam to the inner wall of the drying room, the heat loss to the outside can be effectively reduced. When selecting insulation

materials, factors such as insulation performance, fire resistance, and moisture resistance need to be considered to ensure safety and stability during the drying process.

Special treatment should also be given to weak links such as doors and windows in the drying room, using well sealed door and window structures and adding insulation

sealing strips to prevent heat leakage from these areas.

The calculation of heat demand value based on the capacity of the total production line is a key step. This requires comprehensive consideration of factors such as the

initial moisture content of mosquito coils, the target moisture content after drying, the drying speed, the volume of the drying room, and the ambient temperature. At the

same time, a certain amount of heat loss should also be considered to ensure that the provided heat can meet the actual needs of the drying process.

In the calculation process, the principle of heat transfer and the law of conservation of energy can be applied to establish corresponding mathematical models. Determine

the optimal heat supply parameters through simulation calculations under different operating conditions.

The dehumidification capacity calculation and equipment matching are based on the total amount of mosquito coils within the transmission range of the original

production line to determine the dehumidification capacity. This requires analyzing the relationship between the evaporation of moisture and changes in air humidity

during the drying process of mosquito coils. Based on the ventilation system and air circulation of the drying room, accurately calculate the amount of water that needs

to be removed per hour.

Match the total power of the dehumidification equipment based on the total dehumidification capacity. When selecting dehumidification equipment, heating equipment

and dehumidification equipment can be configured separately, or integrated heating and dehumidification equipment can be used. The integrated heating and

dehumidification equipment has obvious advantages in system control, which can achieve more accurate temperature and humidity control, and the operation is also

more convenient. Through this method, the drying efficiency can be improved and the drying quality of mosquito coils can be ensured.