Commercial waste sorting

Commercial Waste Sorting Technology and System Solutions

Commercial waste sorting is essential for effective resource utilization and is a mandatory requirement under environmental regulations. As a professional manufacturer of waste sorting lines and equipment, we will explore the entire process of commercial waste sorting from an engineering perspective. Our goal is to provide systematic technical insights and solutions for clients, including commercial complexes, industrial parks, and supermarkets.

I. What is Commercial Waste?

Commercial waste refers to solid waste generated by commercial activities, public service institutions, and non-residential areas. It differs significantly from household waste in terms of composition, properties, and quantity. Here are the key features of commercial waste:

1. Variety of Sources: It is produced by various establishments, including shopping malls, supermarkets, restaurants, hotels, office buildings, schools, hospitals, farmers’ markets, and logistics warehouses.

2. Complex Composition: Commercial waste typically includes a large quantity of recyclables, such as cardboard boxes, plastic bottles, metal cans, and glass containers. It also contains perishable waste (kitchen waste) and other materials like discarded packaging and textiles.

3. High Value Density: Compared to household waste, commercial waste has a higher concentration of recyclables of better purity, resulting in greater resource recovery value.

4. Regulatory Requirements: Local regulations, such as “Garbage Classification Management Regulations,” impose clear and strict responsibilities for the classification, collection, and disposal of commercial waste.

II. Core Principles of Commercial Waste Sorting

Commercial waste sorting involves separating materials based on their physical properties using various technical methods. The main principles of sorting include:

1. Size Difference Sorting: Materials are classified by size with the help of screening equipment, such as drum screens and vibrating screens, which divide them into coarse and fine categories.

2. Density and Aerodynamic Difference Sorting: Air separators utilize controlled airflow to distinguish lightweight materials (like plastic film and paper) from heavier materials (such as metals, glass, and kitchen waste).

3. Magnetic Property Sorting: Permanent magnets or electromagnetic equipment are employed to effectively remove ferrous metals from the waste stream.

4. Conductivity Difference Sorting: Eddy current separators create eddy currents in non-ferrous metals (such as aluminum and copper) within an alternating magnetic field, which ejects and separates these materials.

5. Optical Characteristic Sorting: Advanced techniques like near-infrared (NIR) spectroscopy, visible light (VIS) analysis, or artificial intelligence (AI) visual recognition technology are used to accurately identify different materials, such as plastics and paper, allowing for efficient sorting through high-speed airflow.

III. Sorting Steps

Step 1: Pre-processing and Loading

1. Receiving and Unloading: Waste trucks unload mixed commercial waste into the unloading hall.

2. Bag Opener and Uniform Feeding: Using a plate feeder or belt conveyor, the waste is transported evenly to the bag-breaking machine. This machine tears apart sealed waste bags, releasing the internal materials and preparing them for subsequent sorting.

3. Manual Sorting Platform: A manual sorting station is established where workers remove large interfering items (such as furniture and appliances) and hazardous waste to ensure the safety of later processing equipment.

Step 2: Multi-stage Mechanical Sorting

1. Trommel Screening: The material enters the drum screen and is separated into three categories based on size: undersize (mainly small particles of kitchen waste and sand), middlesize, and oversize (typically using various aperture sizes such as 40mm, 80mm, and 150mm). This step effectively separates most organic matter.

2. Magnetic Separation: A suspended magnetic separator is positioned at the conveyor transfer point to remove ferrous metals, facilitating preliminary metal recovery.

3. Air Separation: The screened material is directed to the air separator, where air pressure separates lightweight plastics and paper from heavier materials such as bottles, cans, and residues.

Step 3: Refined Sorting

This stage further purifies the light and heavy materials identified during air separation.

1. Bounce Screen/Disc Screen: These screens are used to further separate flat materials (like paper and cardboard) from three-dimensional plastic bottles within the lighter material stream.

2. Eddy Current Separation: This step accurately separates non-ferrous metals, such as aluminum cans and copper components, from the heavier material stream.

3. AI Intelligent Robot Sorting/Optical Sorting Machine: These technologies represent the core of modern sorting lines.

AI Robot Sorting: Equipped with a high-resolution camera and AI recognition algorithms, robotic arms can precisely pick items made from specific materials (such as PET bottles, HDPE bottles, and paper cups), achieving high sorting purity and flexibility.

Optical Sorting Machine: Utilizing near-infrared spectroscopy technology, this machine quickly identifies the material composition and uses high-speed airflow valves to separate and direct different types of plastics (like PET, PP, PE, etc.) and paper into designated collection bins.

Step Four: Compression and Baling

Once sorted, recyclable materials (such as paper, plastic, and metal) are transported to hydraulic balers, where they are compressed into high-density cubic blocks. This process facilitates easier transportation and sale to downstream recycling plants.

IV. Post-Sorting Processing and Resource Utilization of Commercial Waste

1. Recyclable Materials:

Paper: Sent to paper mills to be transformed into recycled paper.
Plastics: Transported to plastic recycling plants, where they are categorized, washed, crushed, and granulated to create recycled plastic raw materials.
Metals: Delivered to metallurgical plants to be smelted into new metal products.
Glass: Sent to glass manufacturing facilities as raw materials for producing new glass.

2. Other Waste/Combustible Materials:

The high-calorific-value residue left after several rounds of sorting can be sent to cement and power plants as alternative fuels (RDF/SRF) for energy recovery.

3. Non-Usable Residue:

Any useless residue will be disposed of in sanitary landfills.

As an equipment manufacturer with deep roots in the solid waste treatment field, we are dedicated to providing our customers with comprehensive service. This includes project consulting, process design, core equipment manufacturing, installation, and commissioning. Our intelligent sorting system, known for its high sorting accuracy, stable operating performance, and low maintenance costs, is assisting global customers in transforming commercial waste—a “misplaced resource”—into a valuable asset that drives the circular economy.