Solomon’s Seal (Yuzhu) Drying

A traditional Chinese medicinal herb processing enterprise in Guangdong Province has long specialized in the preliminary processing and sale of rhizomatous herbs, such as Solomon’s Seal (Yuzhu). As order volumes increased, their traditional sun-drying methods could no longer meet the required production capacity and quality standards. The client processes 10–12 tons of fresh Solomon’s Seal daily and requires that the moisture content after drying be ≤12%. Furthermore, the drying process must be uniform—avoiding scorched edges or blackened cores—while preserving the herb’s natural color and medicinal aroma. The equipment also needed to be adapted to Guangdong’s humid climate, featuring strong moisture extraction capabilities, all while maintaining controllable operating costs.

Jinlu Machinery designed and customized a 9-meter, 5-layer biomass pellet-fired mesh belt dryer for the client, along with a tailored drying protocol. After being washed, peeled, and sliced ​​into 4–6 mm pieces, the Solomon’s Seal is spread evenly across the mesh belt. Utilizing the five-layer structure, the equipment operates at a constant temperature of 42°C throughout the entire process; the mesh belt’s conveyor speed is slowed down to extend the drying duration. The feeding section features fully open exhaust vents for maximum moisture extraction; the middle section employs moderate ventilation; and the discharge section utilizes reduced ventilation, ensuring a low-airflow drying environment throughout the entire cycle. Finally, the product is cooled using natural air or a low-temperature airflow (35°C) before discharge. The total drying time is approximately 6–8 hours, resulting in a product that feels dry to the touch upon discharge, features uniform cross-sections with a golden-yellow hue, shows no signs of scorching, and meets the required moisture content standards. The equipment is powered by a biomass pellet hot-air furnace featuring automatic feeding and precise temperature control; it is equipped with a high-temperature-resistant, food-grade stainless steel mesh belt, an independent multi-zone temperature control system, a variable-frequency drive for speed adjustment, and high-performance moisture-extraction fans.

Mr. Wang, the client in Guangdong, remarked: “Previously, our Solomon’s Seal processing was entirely dependent on the weather and sun-drying. Now, we can effortlessly dry over 10 tons a day. The color of the dried Solomon’s Seal is excellent—without any blackened edges—and our operating costs are less than half of what they would be with electric drying. The operation is also remarkably simple.” This project has successfully enabled a daily processing capacity of 10–12 tons of fresh raw material, significantly improved drying uniformity, boosted the finished product yield by approximately 15%, and reduced energy costs by 50–60% compared to electric drying—thereby eliminating weather-related constraints and enabling continuous, year-round production.