Construction waste refers to the general term for waste materials such as soil, waste concrete, and waste bricks and stones generated by construction enterprises engaged in production activities such as demolition, construction, decoration, and maintenance. In short, it is engineering waste.

Construction waste can be classified according to its source, including engineering waste, engineering mud, engineering waste, demolition waste, decoration waste, etc.

According to the composition classification, it can be divided into waste soil, concrete blocks, crushed stones, rubble, waste mortar, mud, asphalt blocks, waste plastics, waste metals, waste bamboo and wood, etc.

Due to the large amount of construction waste generated and the presence of harmful substances that cause environmental pollution, it is necessary to carry out scientific and effective treatment and utilization. During the period of rapid economic development, China inevitably generates billions of tons of construction waste every year. If not dealt with and utilized in a timely manner, it will have adverse effects on society, the environment, and resources. But currently, most of the disposal methods for construction waste in China are only underground landfilling, and some are even transported by construction units to suburban or rural areas for open-air storage without any treatment. The harmfulness of this processing method:

1、 Occupying a large amount of land

Taking Beijing as an example, according to relevant data, before the construction of the Olympic project, the original buildings were demolished, and new construction sites had to build 20-30 construction waste disposal sites every year, causing considerable pressure on the site.

2、 Causing serious environmental pollution

Building adhesives, construction waste coatings, paints, etc. are not only difficult to biodegrade polymer materials, but also contain harmful heavy metal elements. This kind of garbage buried underground can cause groundwater pollution and pose a direct threat to the lives of surrounding residents.

3、 Destruction of soil structure

Causing surface subsidence. The current landfill method is to bury 8 meters of garbage and then add 2 meters of soil layer, but it is basically difficult to restore vegetation above the soil layer. But the surface of the landfill area will experience settlement and subsidence, which takes a long time to reach stability.

1、 Classification recycling

Classify construction waste according to the types of materials, such as steel bars, concrete, sand and gravel. Then the recycled garbage is processed, such as crushing, screening, washing, etc., to obtain reusable materials. This method can minimize the demand for natural resources and reduce environmental burden to the greatest extent possible.

2、 Landfilling of garbage

For construction waste that cannot be recycled, it can be chosen to be landfilled. Before landfilling, it is necessary to classify and treat the garbage, remove harmful substances, and design and manage the landfill site reasonably to reduce pollution to groundwater and atmosphere. During landfilling, measures such as covering and filtering layers can be used to improve the stability and safety of landfilling.

3、 Heat value utilization

Some construction waste has a certain calorific value and can be used as fuel, such as brick sand slag, wood, etc. Before utilizing the calorific value, it is necessary to treat the garbage, such as crushing it into small particles or cutting it into fine strips. Then use the calorific value of garbage for combustion, producing steam or electricity, etc., to achieve the reuse of resources.

4、 Biological processing

For organic construction waste such as food residues, wood, etc., biological methods can be used for treatment. This method converts organic matter into fertilizers or biogas through the degradation of bacteria or other microorganisms, thereby achieving resource recycling and utilization. However, it is necessary to control the processing conditions during biological treatment to avoid the production and spread of harmful substances.

5、 Isolate garbage

For construction waste that is severely polluted or difficult to handle, such as harmful substances, radioactive waste, etc., it should be isolated and sealed. Isolation waste can be stored and managed in special areas to avoid damage to the environment and human health.