How is Glass Recycled by DTG Recycle near Coupeville?
Are you curious how glass recycling is done in Coupeville, WA? We’ll explain to you the step-by-step process involved in recycling glass, shedding light on the various techniques and technologies utilized to transform discarded glass into valuable resources.
1. Collecting and Transporting
Recyclable glass is collected from households, commercial and industrial premises in Coupeville. Collection methods vary depending on the location and type of facility. Typically, collection is done through curbside pickup or drop-off points. The glass is transported to a Coupeville recycling center. Glass is usually transported in large trucks or containers. The transport process is carefully managed to avoid breakage. DTG Recycle does not offer a pickup service to recycle glass in Coupeville, WA.
2. Inspecting and Sorting
Once the glass is collected, it is sorted based on color. Separating the glass into colors is important because different colored glass cannot be mixed together during the recycling process. Clear, brown, and green glass are the most common colors collected for recycling.
Common contaminants that are found when recycling glass include the following:
- Non-glass materials – Non-glass materials, such as plastic caps, labels, and metal rings, are common contaminants in glasses. These materials cause problems during the recycling process and reduce the quality of the recycled glass.
- Food and drink residue – Glass containers that are not properly rinsed typically have leftover food or drink residue. This attracts pests and bacteria and causes issues during the recycling process.
- Broken glass – Broken glass is difficult to handle and causes injuries to workers. Broken glass contaminates other materials during the recycling process.
- Ceramics and other materials – Ceramic items, mirrors, and other types of glass (such as Pyrex) have different properties than traditional glass. These materials cannot be recycled with glass containers because they cause contamination and reduce the quality of the recycled glass.
3. Breaking the Glass
The number of hammers used to break glass when recycling depends on the specific Coupeville recycling center and equipment being used. In some Coupeville recycling centers, glass is broken using a single hammer mill. This single hammer mill consists of a rotating drum with swinging hammers that impact and shatter the glass. In other Coupeville recycling facilities, multiple hammer mills are used in a series to break down the glass into smaller pieces.
The size and capacity of the hammer mills used vary depending on the needs of the recycling center. Some recycling facilities use smaller hammer mills for processing glass bottles and jars, while others use larger hammer mills for processing larger items such as car windshields or architectural glass.
4. Screening and Sorting
Trommel screening is a common method used in glass recycling to separate larger pieces of glass from smaller pieces and other materials. A trommel screen is a rotating cylindrical drum with perforated plates that separates materials by size.
In the glass recycling process, the trommel screen is typically used after the glass has been crushed into small pieces called cullets. The cullet is then loaded onto the trommel screen, which separates it into different sizes. The larger pieces of glass that are too big to be used in the production of new glass products are removed and sold for other purposes, such as landscaping or road construction.
Trommel screening is an effective method for separating glass from other materials, such as plastic, paper, and metal, that are mixed in with the cullet. This helps to ensure that the recycled glass is of high quality and can be used to make new glass products.
5. Heating by Using a Fluidized Bed Drier
A fluidized bed drier is a type of industrial drier that uses hot air to dry and heat materials. The fluidized bed drier is used to heat and dry the crushed glass cullet during the glass recycling process. The process starts with the cullet being loaded onto a conveyor belt and put into the fluidized bed drier. As the cullet moves through the drier, it is heated by hot air that is blown through the bed of glass particles. The hot air causes the cullet to become fluidized, allowing for even heating and drying. The fluidized bed drier is used to heat the cullet to a specific temperature, which is important for the recycling process. This temperature is typically around 1500-1600 °F (815-870 °C), which is the melting point of glass.
The size of a fluidized bed drier for glass recycling depends on three main factors. These are the amount of glass cullet being processed, the desired processing rate, and the specific equipment being used. In general, fluidized bed driers for glass recycling range in size from small laboratory-sized units to large industrial-sized units.
6. Primary Rotary Screening
Primary rotary screening is a common and effective method used in glass recycling to separate glass cullet from other materials, such as paper, plastic, and metal. Glass is typically heavier and more rigid than paper and plastic. The rotary screen is designed to filter out these lighter and more flexible materials.
Pulverizing is a crucial step in the glass recycling process that involves crushing and grinding glass cullet into a fine powder or granules. This process is typically performed after the glass has been separated and cleaned to remove any contaminants, such as metal or plastic.
The pulverizing process involves feeding the glass cullet into a machine, such as a hammer mill, which uses rotating hammers to break the glass into small pieces. A typical hammer mill used for pulverizing glass cullet has 12-24 hammers, which are made of a durable material such as high-carbon steel or tungsten carbide.
8. Secondary Rotary Screening
Secondary rotary screening is a common method used in glass recycling to further separate glass cullets into different sizes and remove any remaining contaminants. The secondary screen is typically designed with smaller perforations or openings, allowing for finer separation of the glass cullet into different size fractions. As the drum rotates, the smaller glass particles fall through the perforations and are separated into different size fractions. These fractions are further processed or sorted to create specific size specifications for different applications.
Typical size grades for secondary rotary screening of glass cullets include the following.
- Fine glass powder (less than 0.5 mm)
- Small glass fragments (0.5 to 2.5 mm)
- Medium glass fragments (2.5 to 12 mm)
- Large glass fragments (12 to 25 mm)
9. Classifying Glass Cullets
Classifying glass cullets is an important step in the recycling process that involves separating the cullet into different grades based on its physical characteristics, such as size, color, and composition. This helps to ensure that the final product is of high quality and can be used in a variety of applications.
Listed below are the different methods used to classify glass cullets in the recycling process.
- Optical sorting – This method uses sensors to detect and sort glass cullets based on their color and composition. The sensors identify different colors of glass and remove any contaminants.
- Air classification – This method uses air currents to separate the glass cullet based on its size and density. The cullet is fed into a machine that blows air through it, separating the lighter and smaller particles from the larger and heavier ones.
- Screening – This method involves passing a glass cullet through a series of screens with different-sized perforations or openings. The screens separate the cullet into different size fractions, which are further processed or sorted.
- Magnetic separation – This method uses magnets to remove any metal contaminants from the glass cullet. The cullet is passed through a machine that uses powerful magnets to attract and remove any metal particles.