Daily Knowledge About Fertilizer Production: Spiral Dusting Machine

The spiral dusting machine is a key equipment in fertilizer production lines for preventing particle agglomeration, ensuring good flowability and storage stability by uniformly applying anti-caking powder.

Role of Spiral Coating Machine in Fertilizer Production

The spiral coating machine is used in fertilizer production lines to apply anti-caking or functional powder coatings onto granules. In NPK fertilizer production lines, it can be effectively integrated for surface treatment after granulation and cooling.

Application in NPK Production

Yes, spiral coating machines are suitable for NPK fertilizer lines, particularly for coating NPK granules with anti-caking agents like talc or diatomaceous earth to improve flowability and storage stability.

Fertilizer Types Requiring Coating

Fertilizers that commonly require coating include: high-nitrogen compounds (urea-based fertilizers), hygroscopic blends, premium water-soluble fertilizers, and products needing slow-release properties. The coating prevents caking and dust formation during storage and handling.

Basic Structure and Working Principle

The spiral dusting machine mainly consists of:

· Screw conveying system: Evenly advances fertilizer granules

· Powder spraying device: Precisely controls anti-caking agent dosage

· Mixing chamber: Ensures thorough contact between powder and granules

· Control system: Adjusts processing capacity and powder addition rate

Key Roles in Production Line

Function	Performance	Benefit
Anti-caking	0.5-1.5kg anti-caking agent per ton fertilizer	Reduces caking during storage by over 90%
Flow improvement	30-40% reduction in surface friction coefficient	Enhances packaging and application efficiency
Quality control	Uniform powder coverage	Maintains even nutrient distribution

Application Scenarios

1. Compound fertilizer lines: Typically after cooling and before packaging

2. Organic fertilizer lines: For high-moisture organic granules

3. Specialty fertilizer production: Such as water-soluble fertilizers

Application of Spiral Powder Coating Machine in Compound Fertilizer Production:

In the continuous production process of compound fertilizers, the spiral powder coating machine serves as the core equipment in the post-granulation treatment section, integrated into the powder processing system of the fertilizer production line. This equipment utilizes a high-precision spiral conveying mechanism to apply measured amounts of coating powder (typically anti-caking agents such as diatomaceous earth or talc) onto particle surfaces at controlled rates, forming a uniform functional coating layer. Its technical characteristics are reflected in the process synergy with upstream granulation systems and downstream cooling/screening equipment. Through PLC control systems, it dynamically adjusts the spiral rotation speed (typically controlled at 20-60 rpm) and coating powder dosage (accounting for approximately 0.5-2% of the final product mass), ensuring a particle surface coverage rate exceeding 95%. This significantly improves the product's angle of repose (reducing it by 5-8°) and extends the anti-caking period (by 3-6 months).

Application of Spiral Powder Coating Machine in Organic Fertilizer Production:

In the organic fertilizer production process, the spiral powder coating machine primarily handles the post-treatment function of biomass fertilizers. To address the high adhesiveness characteristics of organic materials, the equipment adopts a large-pitch spiral design (typically 1.2-1.5 times that of standard models) and is equipped with anti-adhesion liners for applying functional additives such as humic acid powder or microbial agents. Unlike compound fertilizer production lines, the organic fertilizer coating process must be completed under low-temperature drying conditions (<50°C). The equipment forms a closed-loop process with fermentation/maturing systems and low-temperature dryers, with the coating dosage dynamically adjusted according to organic matter content (typically 3-8%). This process effectively improves the survival rate of microbial communities in organic fertilizers (increasing by 15-20%) and reduces dust generation (controlled below 3%), meeting the physical property requirements for organic fertilizers specified in the NY525 standard.