Here's the English translation of the previous content about organic fertilizer fermentation times:

Fermentation Duration for Organic Fertilizer Using Turners (Windrow Composting) vs. Fermentation Tanks

The fermentation time for organic fertilizer depends on factors such as raw material properties, equipment type, and environmental conditions (e.g., temperature, humidity). Below are reference durations and key influencing factors for windrow composting (using turners) and closed-tank fermentation:

1. Turner (Windrow Composting)

• Reference Time: 20-30 days (may extend to 40+ days in winter).

• Key Factors:

  • Turning Frequency: Turn every 2-3 days to promote oxygen circulation and accelerate fermentation.
  • Material Preparation: Smaller particle size (≤2 cm), optimal C/N ratio (25-35:1), and moisture content (50%-65%) speed up fermentation.
  • Ambient Temperature: Below 15°C slows microbial activity, requiring longer fermentation.

• Completion Criteria: Pile temperature returns to ambient, material turns dark brown, and emits an earthy smell instead of foul odor.

2. Fermentation Tank (Closed-System Fermentation)

• Reference Time: 7-15 days (high-temperature phase may shorten to 3-5 days).

• Key Factors:

  • Temperature Control: Maintain 55-70°C via heating or aeration to rapidly eliminate pathogens and decompose organics.
  • Material Prep: Requires finer grinding (≤1 cm) and strict C/N ratio (20-30:1).
  • Oxygen Management: Intermittent aeration or agitation in some tanks enhances aerobic fermentation.

• Completion Criteria: Discharged material is loose and odorless, with near-neutral pH (6.5-7.5).

Key Comparison

Optimization Tips

• Turner: Add microbial inoculants or insulated covers to shorten time; build greenhouses or select sheltered sites in winter.
• Tank: Monitor temperature and pH regularly to avoid over-fermentation and nutrient loss.

Adjust processes based on raw materials (e.g., manure, straw) and local conditions.

This translation maintains technical accuracy while ensuring readability for professional audiences. Key terms like "C/N ratio," "aerobic fermentation," and equipment names are preserved in standard industry terminology.

 Special circumstances explanation
The claim that fermentation can be completed in 8 hours is not credible: Some businesses claim that their organic fertilizer fermentation tanks or turntables can complete fermentation in 8 hours, which is inaccurate. Eight hours can only kill parasites, pathogenic microorganisms, and harmful bacteria in organic fertilizer raw materials, achieving harmless treatment of raw materials, but the fermentation process is far from complete.