Excellent precipitation range continuous operation for various residues

Agricultural and sideline processing generates large quantities of high-moisture, high-viscosity and easily agglomerating residue by-products, such as fresh pomace, distiller’s grains, okara and corn fiber. These materials have high initial moisture and poor flowability, so conventional tower-type grain dryers cannot dewater them efficiently. Zhengzhou Wangu Machinery Co., Ltd. offers the WGZ Series Rotary Drum Dryer, which adopts a horizontal rotary-drum continuous drying process specially developed for high-viscosity, high-moisture loose materials, delivering a cost-effective complete drying solution for feed mills, starch plants, alcohol plants and fruit and vegetable processing enterprises.

I. Rotary-Drum Continuous Process Solves Sticky, Wet-Material Drying Challenges

      Unlike tower-type grain dryers that rely on gravity-driven downward flow, the WGZ Series Rotary Drum Dryer operates as a horizontal low-speed rotary drum with continuous processing. Wet material enters at the drum head and fully contacts the hot air, the heated drum shell and the internal lifting flights; as the drum rotates, the flights continuously pick up and spread the material, enlarging the contact area between the hot air and the material, while the material gradually travels from the head to the tail and its moisture is progressively reduced until drying is complete.

       The drum is rotated by a variable-speed motor through a small pinion driving a large ring gear; the speed can be adjusted according to the incoming feed and operating conditions, thereby controlling the residence time of the material inside the drum and hence the final moisture of the dried product. The complete system comprises a hot-air furnace, feed and discharge equipment, the rotary drum dryer, a dust-removal system, an electrical control system and high-/low-temperature ducts. The equipment supports multiple heat sources, including a mechanical chain-grate coal-fired hot-air furnace, a natural gas furnace and a biomass pellet furnace. Multiple inspection doors and manholes on the drum facilitate flight maintenance and material cleaning.

II. Full Continuous Rotary Drying Process

       The WGZ Series Rotary Drum Dryer adopts a horizontal rotary continuous structure: high-moisture wet residue is conveyed into the drum head; the drum rotates at low speed while the lifting flights repeatedly pick up and scatter the material, which moves toward the tail under the combined action of the hot air and the heated shell; the hot air and the material exchange heat fully, and the internal moisture continuously evaporates; the evaporated water vapor is discharged by the induced-draft dust-removal system; the dried material is continuously discharged from the tail to complete the whole drying process. The equipment runs with continuous feeding and discharge without stopping to wait for a batch to finish, and suits 24-hour uninterrupted production.

       The system can adjust the drum speed and hot-air temperature according to the material type and incoming moisture so as to control the residence time and precisely control the final moisture; temperature measurement and electrical control are provided to avoid overheating and scorching. The equipment is mainly intended for residue and feed-ingredient drying, and is not suitable for grain kernels such as paddy, wheat and corn, nor for seed grain.

III. Flexible Models Deliver Overall Value

       Choosing the WGZ Series Rotary Drum Dryer addresses industrialized residue drying scenarios while balancing capacity, operation and maintenance cost, and production stability.

      Targeted handling of difficult materials. It is specially suited to high-viscosity, high-moisture materials such as fresh pomace (apple, pineapple and citrus), distiller’s grains, okara and corn fiber; its large dewatering range can dry fresh pomace from 82% moisture down to below 13% in a single pass, solving the problems of adhesion, agglomeration and uneven drying.

      Large-capacity continuous production. Continuous feeding and discharge enable 24-hour operation; a single unit can process 80–500 tonnes of fresh pomace per day, suitable for industrial-scale production lines.

      Controllable civil-construction cost. The horizontally laid-out drum is low in overall height and can be installed directly in a single-storey plant without tall steel-structure foundations; the packaged modular assembly shortens on-site installation time.

      Simple operation and maintenance. Clear control logic and a simple HMI allow operators to start after brief training; multiple inspection openings facilitate cleaning, and worn flights can be replaced individually.

IV. Hardware Assurance for Implementation

      The drum shell and main components of the WGZ Series Rotary Drum Dryer are designed and manufactured for long-term high-temperature full-load service to guarantee mechanical performance under continuous full-load drying. The complete unit integrates feed and discharge, rotary drying, dust removal, heat source and electrical control; heat sources include coal-fired, natural gas and biomass pellet hot-air furnaces that produce clean air without flue gas contacting the material, and a dust-removal system meets exhaust emission requirements. The equipment mainly serves juice plants, alcohol plants, starch plants and feed mills, installed as fixed units interfacing with the front-end wet-material line for direct drying. Products are manufactured under the ISO quality management system and undergo no-load commissioning before delivery.