Granular organic fertilizer offers balanced nutrients, convenient storage and transport, and ease of application, making it an ideal choice for ecological farming. A standard production line consists of six key stages, from raw material handling to the final product. Huaqiang Heavy Industry has compiled a clear, step-by-step production guide to assist with operational management and project implementation. This standardized process ensures both the safe, hygienic treatment of waste and high-quality final products.
Step 1: Raw Material Preparation and Pre-treatment. Suitable raw materials include organic waste such as livestock and poultry manure, crop straw, fungal residue, and sludge. These should be blended to achieve a carbon-to-nitrogen (C:N) ratio of 25–30:1. Straw or wood chips may be added to adjust moisture levels and improve aeration. Impurities—such as stones and plastics—must be removed to prepare the material for fermentation.
Step 2: Aerobic Composting (Fermentation). The prepared materials are arranged into windrows (long piles). Fermentation microbial agents are added, and a compost turner is used to periodically turn the piles, ensuring a sufficient oxygen supply. The fermentation process typically lasts 15–20 days. During the high-temperature phase, pathogens and insect eggs are eliminated, organic matter is broken down, and odors are neutralized. Once the material turns dark in color, becomes loose, and is free of unpleasant odors, the decomposition (maturation) process is complete. Fermentation is the core stage for ensuring the safety of organic fertilizer; the optimal temperature range is 55–65°C.
Step 3: Crushing, Screening, and Mixing. Since the matured material often contains clumps, it is fed into a crusher and then screened to achieve the required particle fineness. Nitrogen, phosphorus, and potassium (NPK) nutrients or beneficial microbial agents can be added as needed. The mixture is then thoroughly blended in a mixer to ensure consistent nutrient content across every batch. Oversized or coarse particles are sent back for re-crushing, allowing for the efficient recycling of materials.
Step 4: Granulation. The blended powder is fed into granulation equipment—common types include disc granulators, flat-die pellet machines, or new type organic fertilizer granulators. With the addition of an appropriate amount of moisture, the powder particles aggregate to form organic fertilizer granules, typically 3–5 mm in size. Because the granulation process directly influences the appearance, hardness, and yield of the final product, precise control of the material's moisture content is essential.
Step 5: Drying and Cooling. Newly formed granules have a relatively high moisture content; they are first fed into a rotary dryer for low-temperature drying, reducing moisture to below 15%. Subsequently, they are transferred to a cooler to bring their temperature down to ambient levels. This stage prevents the granules from molding or sticking together, enhances their structural strength, and extends their shelf life. When producing bio-organic fertilizers, the drying temperature must be strictly controlled to ensure that the live microbial cultures remain viable.
Step 6: Screening, Coating, and Packaging. The cooled granules undergo vibration screening to separate the product into qualified granules, fine powder, and large clumps; the fine powder is recycled back into the granulation process. If anti-caking properties are required, a coating step can be added. The qualified granules are then transported to an automated packaging machine for precise weighing, sealing, and labeling before being placed into storage. The entire process operates as a closed-loop system, ensuring high raw material utilization and controllable pollution levels.
Following this multi-step process enables the consistent production of granular organic fertilizers that meet industry standards. These products are suitable for various cultivation settings—including orchards, vegetable farms, and field crops—thereby supporting the development of green agriculture.
_800x600.jpg)
_800x600.jpg)