Construction waste refers to solid waste generated during the demolition, construction, and decoration of buildings, including soil, concrete blocks, crushed stones, brick and tile fragments, waste mortar, mud, asphalt blocks, waste plastics, waste metals, waste bamboo and wood, etc.

 

At present, the vast majority of construction waste is transported to the outskirts or countryside by construction units without any treatment, and is stored or buried outdoors, consuming a large amount of construction funds such as land acquisition fees and garbage removal fees. At the same time, the problems of scattering, dust, and sand flying during the removal and stacking process have caused serious environmental pollution. The fine powder and soluble phenolic alkali components of abandoned concrete will be dispersed underground by wind and rain, which will deteriorate the soil and groundwater quality.

 

Solid waste is not useless waste, but a useful resource and precious wealth. The ultimate solution for solid waste treatment lies in "waste resource utilization", which is becoming a fundamental policy of waste management systems in countries around the world. This can not only improve social benefits, make full use of resources, and achieve certain economic benefits, but also achieve the goal of environmental protection.

 

If handled properly, it has the following uses:

 

1. After crushing, it can be used as a building foundation cushion or road base, which is the simplest and most commonly used method of recycling;

 

2. Produce concrete block bricks, paving bricks, recycled permeable bricks and other brick products after crushing;

 

3. Replacing some natural sand and gravel aggregates to produce recycled aggregate concrete is the most valuable method for treating waste concrete. Recycled concrete made from recycled aggregates is a type of green concrete.

 

At present and in the future, China cannot continue to rely on traditional extensive growth methods to promote modernization. We must accelerate the development of circular economy, reduce energy consumption and waste emissions from the source, achieve efficient and circular utilization of resources, and promote sustainable and healthy economic and social development. Therefore, the utilization of solid waste resources is urgently needed.

 

Main process of solid waste resource utilization

 

Sorting: removing large debris from raw materials through heavy-duty screening or manual labor;

 

Iron removal: Removing small and medium-sized steel bars, iron wires, and other debris;

 

Crushing: Crushing large aggregates into particle shapes that meet the requirements for regeneration;

 

Screening: Classify and screen according to regeneration requirements;

 

Wind selection: remove light impurities from the aggregate again;

 

The entire process is equipped with dust removal techniques such as spraying, mist cannon, and membrane dust suppression.

 

Main equipment for solid waste resource utilization

 

Crushing is an important process for the regeneration of solid waste. Currently, the most commonly used equipment for solid waste treatment is mobile crushing station equipment, which has the following advantages:

 

Without any foundation or supporting construction needs, it is convenient to process on-site for demolition;

 

Capable of quickly moving workstations, eliminating material dumping processes, and reducing recycling costs;

 

Flexible combination and matching under different working conditions can reduce investment costs;

 

Equipment operation and maintenance are simple, reducing personnel investment costs;

 

The equipment is equipped with sound insulation and dust removal devices, and has undergone dust and noise reduction treatment, which has met the national workshop environmental protection testing standards.

 

Prohibition of river sand mining, rectification of the sand and gravel industry, shortage of sand and gravel, and soaring prices. The resource utilization of solid waste is particularly urgent, and its recycled materials can replace some artificial and natural sand and gravel aggregates to achieve recycling, which may become a new opportunity.