Comparison of advantages and disadvantages of heat pump dryer drying methods

Comparison of drying costs

In terms of drying cost, it includes the electricity cost required for material drying, labor cost, damage rate of material drying, dryer failure rate, purchase cost, and so on.

The advantages of freeze-drying and vacuum drying are: strong technical, but obvious disadvantages: currently, the equipment has not been mass-produced and has only been promoted in a small amount in the market, resulting in higher prices. The biggest drawback of electric heating is the high cost of electricity due to the conversion of electricity from work to heat energy. The disadvantage of both shade drying and sun drying is that they require labor costs to be reversed, which is time-consuming and laborious.

The heat pump dryer applies the inverse Carnot principle, which can efficiently transfer heat from the air to the drying room for "free" drying of materials. Its advantages are naturally energy-saving, environmentally friendly, and high energy efficiency, but its disadvantage is the need to build an air energy heat pump drying room, which is more suitable for large-scale batch drying.

Comparison of drying ranges for materials

Drying materials mainly include seafood with high protein and moisture content, fruits and vegetables with high sugar content and easy decay, and roots and stems with strong water retention properties.

The advantages of vacuum and freeze-drying are that they can dry materials that are not heat-resistant or resistant to oxidation, while some fruits and vegetables are afraid of the cold and cannot be dried, such as banana slices that are damaged during drying. The disadvantage of shade drying and sun drying is that they can only target roots and stems with low moisture content and are not easy to rot. Uneven sun drying of seafood can easily cause internal decay and deterioration.

Heat pump dryers are almost suitable for drying most materials, including seafood such as sea cucumber, starfish, squid, abalone, fruits represented by persimmons, bananas, apples, lychees, chemical coatings such as helmet paint drying, and fuel drying such as coal and sludge. The advantages of heat pump drying are its wide drying range and strong adaptability.

Comparison of drying effects

The highest requirement for drying effect is for the drying of traditional Chinese medicine, as high temperatures can easily lead to changes in the properties or active ingredients of the medicine. Obviously, temperature control is the most crucial.

The disadvantage of sun drying is that it is difficult to control the temperature naturally. The high temperature during noon sun drying can sometimes result in unpredictable weather conditions, leading to the inability of the traditional Chinese medicine sun drying process to ensure its efficacy. Secondly, there has been no mention of vacuum drying or freeze-drying for medicinal herbs. The disadvantage of freeze-drying is that it turns the moisture of medicinal materials into ice, making it inconvenient to store and uncomfortable for doctors to prescribe dried medicinal materials according to the standard of 10g.

In order to meet the temperature and humidity control needs of traditional Chinese medicine, the heat pump dryer adopts a PLC control system (including control panel) designed by the R&D team of Keling, equipped with modular drying dehumidification mode and drying temperature setting advantages. The advantage of a heat pump dryer is that it allows Chinese medicinal materials to evaporate water at the optimal drying temperature without damaging their chemical composition.