PTFE semi-permeable membrane aerobic fermentation of domestic waste to produce organic fertilizer

PTFE Semi-permeable Membrane Aerobic Fermentation of Domestic Waste to Produce Organic Fertilizer

1. Brief Introduction

PTFE semi-permeable membrane aerobic composting is a clean recycling technology for classified organic domestic waste including kitchen leftovers, fruit and vegetable residues, garden trimmings. It converts biodegradable domestic waste into qualified commercial organic fertilizer via enclosed aerobic fermentation, overcoming defects of conventional open compost such as odor overflow, rain-induced leachate, serious nutrient loss and weather-restricted production.

2. Working Principle

The core material is expanded PTFE composite microporous membrane with 0.1–0.3 μm aperture and textile reinforcing layers for mechanical strength:

1. Small-molecule water vapor and CO₂ produced by microbial degradation penetrate outward to drain excess moisture inside piles and prevent anaerobic putrefaction.

2. Large-molecule odorous gases (NH₃, H₂S, VOCs), germ-containing mist and fine dust are blocked inside the pile to control odor pollution.

3. The covered structure retains biological heat from microbes, maintaining stable thermophilic temperature of 55–70 ℃ for over 7 consecutive days to kill pathogens, parasite eggs and weed seeds to achieve harmless treatment.Bottom forced aeration continuously supplies oxygen to sustain vigorous aerobic microbial activity.

3. Complete Production Process

3.1 Raw material pretreatment

Sort domestic waste to remove inorganic impurities like plastic, glass and metal; crush organic fractions, mix with straw, sawdust or bran to regulate moisture to 55%–65% and C/N ratio at 25:1~30:1.

3.2 Pile construction and membrane covering

Build strip compost piles above pre-laid aeration pipelines, then fully seal the whole pile with fixed PTFE semi-permeable membrane to form an enclosed fermentation space.

3.3 Controlled aerobic fermentation

Intelligent aeration system automatically adjusts air supply according to real-time pile temperature, oxygen content and humidity. No frequent pile turning is needed. The whole fermentation cycle lasts 20–32 days, much shorter than traditional open compost (60–90 days).

3.4 Aging and fertilizer finishing

After high-temperature fermentation, materials undergo aging maturation. Mature compost is crushed, screened and optionally granulated into powdered or granular organic fertilizer conforming to relevant national standards.

4. Technical Advantages

1. Environmental protection: More than 95% odor interception; rainwater isolation avoids leachate generation and soil/water contamination.

2. High resource efficiency: Waste volume reduces by 45%~60%, nitrogen volatilization loss drops sharply for higher organic matter and nutrient content of finished fertilizer.

3. Cost saving: Cancel regular turning work to cut labor and machine costs; PTFE membrane is corrosion-resistant, anti-aging with long service lifespan.

4. All-weather production: Runs stably under rainy, low-temperature or high-temperature conditions, suitable for community and village decentralized waste treatment.

5. Application Prospect

Widely used in residential communities, rural villages, farmers’ markets and small domestic waste transfer stations. Supported by garbage classification and circular agriculture policies, this technique realizes domestic waste reduction, harmlessness and resource reuse, with promising popularization value.