I. Organic Waste and Its Sources

Organic Waste

Organic waste sorting: Organic waste, also known as wet waste or biodegradable waste, refers to solid waste that comes from plants and animals. It can be easily decomposed by microorganisms and contains a high percentage of organic matter. Key characteristics of organic waste include a high moisture content (typically 50%-80%), a high volatile solids content, the potential for easy putrefaction, the production of odors, and the generation of leachate.

Main Sources:

– Kitchen Waste: This includes food scraps, leftovers, fruit peels, vegetable leaves, expired food, and more, generated by households, restaurants, and canteens. Kitchen waste is the most significant source of organic waste.

– Garden and Landscaping Waste: This consists of branches, fallen leaves, weeds, flowers, and other materials produced from pruning trees and maintaining gardens.

– Agricultural Waste: This includes crop straw, fruit and vegetable residues, livestock and poultry manure, and other organic materials generated in agriculture.

– Other Sources: These include by-products from food processing plants, as well as expired or spoiled food items.

II. Hazards of Improper Organic Waste Sorting

1. Environmental Pollution:

– Soil and Water Pollution: Leachate from decaying waste contains high concentrations of organic matter, heavy metals, and pathogens, which severely pollute soil and groundwater.

– Air Pollution: Under anaerobic conditions, the decomposition of organic waste produces large amounts of methane (CH₄), a greenhouse gas that is 21 to 24 times more potent than carbon dioxide. This process also releases unpleasant gases such as hydrogen sulfide and ammonia.

2. Resource Waste: Direct landfilling results in the loss of significant amounts of potential biomass energy and organic fertilizer, contradicting the principles of a circular economy.

3. Increased End-of-Life Treatment Load: Organic matter in mixed waste contaminates recyclables, such as paper and plastics, which reduces their recycling value. Additionally, this contamination increases instability in calorific value and contributes to corrosiveness issues associated with incineration.

III. Organic Waste Sorting Solutions

Efficiently and cleanly separating organic waste from mixed waste is the prerequisite and key to achieving its resource utilization.

Guoxin Machinery‘s sorting solution combines multiple technologies:

1. Pre-treatment and Bag Breaking:

Mixed household waste is first evenly conveyed by a plate feeder to the bag breaker. This equipment effectively tears open sealed garbage bags, releasing the contents and creating conditions for subsequent sorting.

2. Screening (Key Step):

Trommel Screen: This is the core equipment for sorting organic waste. Using screens with different apertures, materials are graded by size. Smaller components with particle sizes similar to kitchen waste (typically <80mm) are screened out, including a large amount of organic waste.

3. Air Separation:

The screened material enters the air separator. Using airflow, lightweight materials such as plastic film and paper are separated from heavier materials such as organic waste and glass/ceramics.

4. Magnetic Separation and Eddy Current Separation:

· Magnetic separators are used to remove ferrous metals.

· Eddy current separators are used to separate non-ferrous metals such as aluminum and copper.

5. Intelligent Sorting (Improved Precision):

For scenarios with extremely high requirements, near-infrared (NIR) optical sorters can be introduced. This equipment can identify the molecular structure of materials, accurately separating organic waste from other impurities (such as plastics and rubber), or ensuring the purity of organic waste.

Guoxin Machinery’s Technical Advantages: Our sorting line design emphasizes a balance between high recovery rates and low impurity rates. Through precise control of equipment parameters and optimized process combinations, we ensure that the purity of the sorted organic waste meets the requirements of subsequent composting or anaerobic fermentation processes.

IV. Post-Sorting Processing and High-Value Utilization

1. Aerobic Composting:

Under controlled conditions, organic waste is degraded into stable humus—organic fertilizer or soil conditioner—through the action of microorganisms (bacteria, fungi, etc.). This process is technologically mature, and the products can be used in landscaping and farmland fertilization, achieving a natural cycle of matter.

2. Anaerobic Fermentation for Biogas Production:

In an anaerobic environment, organic waste is decomposed by anaerobic microorganisms, producing methane-rich biogas and digestate.

• Biogas can be purified into biomethane (Bio-CNG) and integrated into urban pipeline networks or used as vehicle fuel; it can also be used for power generation and grid connection.

• After treatment, the digestate can be returned to the fields as high-quality liquid fertilizer.

3. Insect Farming:

Using black soldier flies, fly larvae, and other insects to treat organic waste. Insect larvae efficiently feed on and convert organic matter, becoming high-protein insect feed themselves, and their excrement is excellent organic fertilizer. This is a new and efficient treatment method.

Finally, source separation and precise end-of-pipe sorting of organic waste are not only urgent needs for environmental protection but also strategic measures for developing a circular economy and tapping into urban “mining.” As a professional waste sorting solution provider, Guoxin Machinery is committed to helping customers overcome the “last mile” of organic waste resource utilization through advanced, reliable, and intelligent sorting technologies and equipment, achieving a win-win situation for both environmental and economic benefits.

In the future, we will continue to innovate, promoting sorting technology towards greater intelligence and precision, contributing our professional strength to building a sustainable society.