Waste processing plant modernization

C&DW are formed from activities such as the construction and demolition of buildings and urban infrastructure, including road construction and repair.

Significant differences in terms make it difficult to compare the volume of waste recycling between countries.

The potential for recycling and re-using construction and demolition waste is enormous, as their components are usually expensive. There is an extensive market for secondary materials used in the construction of roads, drainage systems and other facilities. C&DW separation and recovery technology is available and usually does not require a large investment.

Despite the large investment opportunities, the percentage of recycling and recovery of construction waste in the EU varies widely (from 10 to 90%). If sorting is not used on construction sites, C&DW stream can contain hazardous components that pose environmental risks and complicate recycling.

Today the construction of C&DW recycling plants is a complex technical task that requires significant practical experience and advanced technologies from the engineering company.

Knowledge of the characteristics and types of waste contributes to the efficiency of sorting and improves the quality of processing. It is especially important to take into account the specifics of various types of hazardous waste and their impact on the environment.

Processing of stone, brick and concrete waste

Crushed stone, concrete and brick make up the bulk of the waste associated with the construction and renovation of buildings, engineering structures and roads.

Disposal of such waste is usually carried out by separating and shredding useful materials.

This type of waste becomes the basis for the creation of aggregates and other products.

Demolition stone and similar materials can also be crushed and used as aggregates. Construction of aggregate plants is gaining momentum and the use of C&DW is very beneficial in this industry.

Concrete is one of the most common types of construction waste. This is not surprising since concrete structures are most often used in modern construction and renovation. Almost every construction project involves the dismantling of concrete structures as one of the main initial activities, so the need for concrete processing is growing.

The practice of European countries such as the Netherlands and Denmark, where there is a shortage of natural stone materials, shows that recycled concrete-based aggregates can be used to produce high-strength materials.

For this purpose, it is important to essentially basic processing technology (crushing, screening) and to increase the efficiency of sorting concrete waste before processing.

Recycling of asphalt concrete

During the repair and maintenance of the road surface, a huge amount of asphalt concrete is produced.

Asphalt concrete is also a type of recyclable construction waste.

There are two technologies for on-site processing of asphalt concrete:

• Hot recycling. Using special portable equipment, the old material is heated, after which a new hot asphalt concrete layer is applied on top.

• Cold recycling. This is one of the most effective techologies for recovering this type of construction waste. It consists in grinding asphalt in an aqueous medium with the addition of a stabilizing substance to the resulting mixture.

Recycling of asphalt concrete in special factories ensures the best results.

The road surface is removed by milling and then transported to the plant for recycling. Recycling asphalt concrete provides significant economic benefits and helps to reduce the consumption of valuable natural resources such as oil.

Ceramics recycling

As a valuable building material, ceramics have high mechanical strength.

Ceramic products are recyclable and reusable. Recycled ceramics find many uses in construction, including park alley sidewalks, drainage systems, and more.

During the construction of waste processing plants, high-tech equipment is used to ensure high efficiency of recycling and obtaining a high-quality secondary product for various areas of use.

The task of engineering teams at the design stage is to optimize the technology for processing construction waste for the needs of a particular customer, taking into account the type of waste, its composition and the possibility of reuse.

Construction of car recycling plants

Car scrapping is an acute problem in developed countries.

In the United States alone, up to 15 million old vehicles are scrapped every year. Environmentally friendly recycling of used vehicles is aimed at achieving a level of reuse and recycling of at least 85% of the total weight.

These requirements are established during the vehicle design phase, which is why modern car recycling plants recover a significant amount of valuable materials from each vehicle. Wherever possible, manufacturers limit the use of hazardous substances and make it easier to disassemble, reuse and recycle components.

Construction requirements for car recycling plants

The construction of car recycling plants in each country is subject to specific requirements.

So, places for collection and storage of equipment should have a waterproof surface, as well as equipment for collecting oils, precipitators and degreasing devices.

Plants should have suitable storage areas for components resulting from vehicle dismantling, including storage facilities for environmentally safe storage of parts contaminated with engine oil.

They should also be equipped with suitable containers for lead-acid batteries, filters containing environmentally hazardous polychlorinated biphenyls or terphenyls; equipment for draining liquids.

Adequate storage tanks are also required for separate storage of fluids such as fuel, gear oils, coolants, antifreeze, brake fluids and other potentially hazardous liquid waste. To avoid the risk of fire due to the accumulation of large quantities of tires, they must be stored in suitable storage facilities after disassembly.

Engineering companies that build vehicle recycling plants must consider numerous requirements, including local car recycling standards.

Stages of car recycling

The processing of used vehicles takes place in several stages:

• Disassembly.
• Pressing.
• Shredding.
• Recycling.

All operations for the separation and storage of components are carried out in such a way as to ensure their suitability for subsequent reuse.

Disassembly work involves separating reusable automotive parts and collecting components classified as hazardous. This includes lead-acid batteries, catalytic converters (containing platinum and rhodium), fuels, engine oils, manual and automatic transmission oils, brake fluids, hydraulic clutch fluids, and more.

Various liquids are stored in special containers or processed on appropriate processing lines.

The car disassembly process must be carried out very carefully to reduce the amount of hazardous substances in the waste during subsequent processing.

The metal remains of the car are pressed in portable and stationary hydraulic presses to take up less space for possible transportation. Sometimes portable presses are preferable, as they can be used at waste collection sites in order to reduce the cost of transporting scrap metal.

The next step is crushing the scrap metal.

For this, different types of equipment are used, in which the car body goes through several stages.

As a result, the body is crushed into pieces of several centimeters in size.

The resulting material is thoroughly processed, as a result of which ferrous metals are separated from non-ferrous ones. The non-recyclable fraction after these processes will be less than 20% of the vehicle weight.

Used car tires and their components are not hazardous and can be 100% recycled. They consist mainly of rubber (43-48%), soot (21-22%), metal (15-27%), textiles (5%). At the end of their life cycle, tires can be transformed by physical or chemical processes into a new product or raw material for other applications.

Possible applications of the obtained rubber granules or powder:

• Synthetic coatings.
• Coverings for sports grounds.
• Modification of asphalt mixtures.
• Production of conveyor belts.
• Thermoplastic elastomers.
• Activated carbon.

Automotive lead acid batteries are also recycled.

The batteries are separated and the harmful lead acid paste is extracted.

Pieces of lead and plastic are submerged in pools of water. Here, lead and other metals sink, and light plastic parts float to the surface.

Car recycling plants separate battery materials. The plastic parts are separated and a special machine blows them into the container. They are sent to the plastics processing plant. The acid from the lead acid paste is neutralized and converted to water. Lead can be used in the future for the production of new batteries.

Recycling vehicles has important economic and environmental implications.

If you are interested in financing and construction of a car recycling plant under an EPC contract, please contact our representatives at any time.

Construction of plants for the processing of waste electrical and electronic equipment

Electrical and electronic equipment is an important part of everyday life.

Rapid technical development in this sector leads to a constant stream of new solutions and shorter product lifetimes.

Globally, the annual volume of waste electrical and electronic equipment (WEEE) ranges from 7 to 20 kg per person per year. The difference is caused by different understandings of this term. In the United States, the WEEE category includes only information and telecommunications equipment, and in Europe, the term also covers large appliances, refrigeration equipment, and medical devices.

Importance of WEEE recycling

Against the backdrop of a deteriorating environmental situation and a shortage of resources, the construction of new plants for the processing of waste electronic and electrical equipment today has become a priority task not only for private companies, but also for governments.

WEEE contains rare metals including gold, silver, palladium and platinum, as well as potentially hazardous substances such as lead, mercury, cadmium and beryllium. Therefore, responsible handling of electronic waste should include reusing working devices, repairing damaged equipment, and properly disposing of non-recyclable components.

The first two options are the most desirable as they extend the life of the products and improve resource efficiency.

Recycling WEEE allows companies to reuse valuable metals, significantly reducing their environmental impact.

Electronic manufacturers are the main consumers of metals such as nickel and nickel alloys, cobalt alloys, titanium and titanium alloys. As raw material depletes and increases in value, investment in WEEE recycling plants is becoming an increasingly profitable solution.

In addition to recovering precious metals, WEEE recycling reduces the environmental impact of primary production. This is due to such energy-intensive stages as mining and smelting of precious and special metals, which are associated with significant emissions of carbon dioxide.

Waste electrical and electronic equipment poses a significant risk to the environment and health if not properly used. Although WEEE only accounts for 2% of landfilled waste, it contains about 70% hazardous components.

These include lead in cathode ray tubes and solders, mercury in switches, polybrominated flame retardants in printed circuit boards, plastic in housings and cables, and selenium, cadmium, chromium, cobalt, and many other contaminants.

Sorting and mechanical processing of electronic waste

During the construction of waste processing plants focused on recycling electronics waste, close attention is paid to technological lines for sorting and mechanical processing.

This stage aims to separate waste streams, mainly metal, glass and plastic, which will subsequently be recycled. The complexity of pre-processing is determined by the customer’s requirements for the finished product. Additional mechanical processing not only increases the cost of the process, but can also lead to significant losses of precious metals.

Complex components and devices such as printed circuit boards, mobile phones and other small household appliances are removed from the waste stream before processing. When the boards are not removed by hand or crushed, precious metals are mixed with low-value fractions such as glass and aluminum. Mixing complex components can lead to losses of up to 40% of precious metals.

After separation, the fraction of ferrous metals is sent for the extraction of iron and aluminum to furnaces, and copper alloys are usually fed to automated lines for the extraction of precious metals, copper and other non-ferrous metals.

Recovery of metals from WEEE

WEEE pyrometallurgical processing consists of melting waste electrical and electronic equipment in high-temperature furnaces.

This technological process is used to recover copper and precious metals that can dissolve in copper, such as silver, gold, platinum, and palladium.

Electronic waste can be recycled into small furnaces.

Their processing into copper sulfide concentrate is common for large smelters. The process consists of several stages. The first involves separating hazardous components such as batteries, cathode ray tubes, mercury lamps, and more.

Typically, high-quality electronics waste does not go through the grinding stage, but is sent directly to the smelter. This prevents the formation of dust containing precious metals and significantly reduces the loss of metals and components in waste material streams that cannot be recovered.

Plastic components are difficult to recycle due to the fact that they contain a mixture of flame retardants, pigments, etc.

However, they can be used as fuel for smelting.

Although pyrometallurgical processing is the most common method for recovering precious metals from waste electrical and electronic equipment, this technology also has some disadvantages. These include the inability to recover aluminum and iron and the formation of dioxin emissions from the melting of halogenated flame retardants and PVC in the waste.

Over the past two decades, WEEE hydrometallurgical processing has become increasingly popular due to its high predictability, and easier process control compared to pyrometallurgical methods.

Engineering companies that build plants for the processing of waste electrical and electronic equipment develop process flow diagrams tailored to the needs of the customer.

The choice of technology is determined by the type and quantity of waste, product requirements, etc.

Construction of RDF processing plants

Typically, the production of a combustible fraction from municipal solid waste (MSW) includes two stages – waste pretreatment and recovery.

This fraction, recovered from the solid waste stream, is known as RDF fuel.

In terms of composition, RDF is a mixture of substances with higher flammability (eg paper, plastic) compared to the components in the overall waste stream.