Pig Manure Management: A Methodology for Environmentally Friendly Decision-Making

Area of Science:

• Agricultural Engineering
• Environmental Science
• Animal Science

Background:

• Increasing farm size raises profitability but poses environmental and animal welfare challenges.
• Inefficient pig manure management leads to significant nutrient losses (8-50%).
• Optimizing manure handling technology is critical for sustainability.

Purpose of the Study:

• Develop a methodology for accurate accounting of manure quantity, fractions, nitrogen (N), and phosphorus (P) content.
• Apply the methodology to select the optimal processing technology for a large-scale pig farm.
• Validate the methodology against existing farm data.

Main Methods:

• Calculation, analysis, and modeling techniques for manure accounting.
• Application to a 17,800-head farm in the Leningrad Region (54,750 t/year manure).
• Technology selection: separation, aeration, sedimentation (liquid), passive composting (solid).

Main Results:

• Selected technology yielded 278.94 t/year of N and P in end-products.
• Total nutrient loss across all stages was 26%.
• Specific costs: USD 55.5/ton manure (capital and operating).

Conclusions:

• The developed methodology accurately supports planning manure-based end-product production.
• It enables achieving specific nutrient content targets based on processing technology.
• The methodology validates well against real-world farm data (0.9-12.5% mass difference).