Bidding for property construction waste

The following is the analysis of the current situation of Xi 'an construction waste brought by Zhong Da Consulting and the related contents of recycling measures for your reference.

Introduction to 0

With the development of China's economy and the implementation of sustainable development strategy, all departments attach great importance to developing environmental protection industry and improving the comprehensive utilization rate of resources. In recent years, the process of urban modernization transformation and rural urbanization in China has accelerated, and the harm of construction waste to human beings has become more and more serious. According to statistics, at least 3- 107~4- 107m2 old buildings are demolished every year in China, resulting in hundreds of millions of tons of construction waste, of which more than 40 million tons are generated in the construction process alone. For these construction wastes, most of them are transported to suburbs or villages without any treatment, and they are disposed of by open-air stacking or landfill. This treatment method not only occupies a lot of cultivated land and construction funds, but also causes problems such as scattering and dust flying in the process of clearing and stacking, which intensifies environmental pollution and causes more and more unbearable pressure on the social environment. It can be seen that the comprehensive utilization of construction waste has become an important issue that the society urgently needs to study and solve. How to turn construction waste into treasure and create good economic benefits on the premise of saving investment has become an urgent problem for the whole society. This paper analyzes the present situation of construction waste in Xi city, and puts forward some suggestions on its reuse in order to attract the attention of the whole society.

Analysis of the present situation of 1

At present, the construction waste in Xi city mainly comes from the reconstruction of urban villages, municipal engineering construction and the proposed subway project.

Transformation 1. 1 village in the city

Take the demolition of Li Jiacun clothing market as an example to calculate: the demolition area is about 30- 104m2, and the estimated construction waste per square meter is 0.7m3, and * * * is 2 1- 10 4m3. It is reported that 157 villages in Xi 'an have been rebuilt within five years, that is, about 3 1.4 construction wastes of the size of Li Jiacun are generated every year, and the annual amount of this construction waste can reach 659.4- 10 4 m3, which is estimated to be 329.7- 10 4 m3 by half. In addition, it is estimated that the construction waste generated by sporadic demolition of this project accounts for110, that is, 32.97- 10 4m3. From this, it is estimated that the annual construction waste generated by the renovation and demolition of urban villages in Xi City is 362.67- 10 4m3.

1.2 municipal engineering construction

In recent years, the investment in municipal engineering has doubled, and with the expansion of the scale, the types of garbage have also doubled. There are grass-roots materials from roads: mud-bound macadam and graded macadam; Surface material: asphalt macadam, asphalt concrete and cement concrete; Sidewalks: Ballast blocks such as concrete kerbs, floor tiles, and gravel are all objects of landfill. Take the BRT trunk road to be completed in 2007 as an example, which will cross the east and west sides of Xi 'an. The author understands that the original pavement is concrete pavement and the subgrade is mud-bound gravel. If the width is 14m and the length is 20km, the road garbage is 2.8- 10 4m3 and the concrete fragments are 4.2- 10.

The service life of asphalt pavement is generally around 10~ 15a. If the asphalt pavement of the roads and expressways under its jurisdiction is expected to be 30m wide and 0.05m thick, and 20km is renovated every year, the asphalt waste will be 3- 10 4m3.

According to the above two items, it is estimated that municipal engineering will produce construction waste 10.00- 10 4m3 every year.

1.3 proposed subway project

If the subway is built at a speed of 2km per year, the excavated earthwork can reach more than 40m3 per excavation 1m, and there will be 8-10.4 m3 of earthwork throughout the year, and these soils are really good materials for foundation engineering and sintered bricks. If you don't use it, it will become waste and pile up in different places.

The annual recycling amount of construction waste generated in Xi 'an is: building 362.67- 10 4m3, municipal100-104m3, subway 8.00- 10 4m3, * * 380.67-65438.

2 advanced experience

2. 1 foreign advanced experience

Japan has a small land area and relatively scarce resources, so they regard construction waste as a by-product of construction and redevelop it as a renewable resource. 1977, the Japanese government formulated the Code for the Use of Recycled Aggregates and Recycled Concrete, and successively established recycling processing plants in various places to produce recycled cement and recycled aggregate, with the maximum production scale reaching 100t-h- 1. 199 1 year, the Japanese government enacted the Law on the Promotion of Resource Reuse, which stipulates that construction wastes such as muck, concrete blocks, asphalt concrete blocks, wood and metals generated during construction must be sent to recycling facilities for treatment. According to relevant data, in some areas of Japan, metal and sand are removed from recycled construction waste, and hydrated lime is added to make round blocks for special garbage electric stoves. The average heat generated by this lump coal is about 1/20 of that of ordinary standard coal.

Cyclean Company in the United States can recycle 65,438+0,000% of the old asphalt pavement fabric with the same quality as the new asphalt pavement fabric, and the cost can be reduced by 65,438+0/3, which not only saves the cost of garbage removal and treatment, but also reduces the pollution to the urban environment. A real estate development company in Idaho, USA, built a1330m2 residential building with construction waste. The walls are made of recycled tires and aluminum alloy waste, the steel used for roof trusses is recycled from construction sites, the plates are made of sawdust and sawdust with 20% polyethylene, and the roofs and walls are made of old newspapers and cartons. This new type of residential building won the residential style award from the American Association of Residential Builders, and was officially named as a resource-saving residential building.

2.2 China advanced experience

In 1995, the relevant departments of our country promulgated the Regulations on the Treatment of Municipal Solid Waste, which put forward the problem of construction waste for 1 time. However, this is a measure to limit the generation and discharge of construction waste, and it cannot fundamentally block the source of a large amount of construction waste. The promulgation and implementation of the Regulations on the Management of Urban Construction Waste issued by the Ministry of Construction has played a positive role in promoting the management of urban construction waste and maintaining a good city appearance and environment.

In 2002, Nanjing Municipal Solid Waste Comprehensive Utilization Development Company cooperated with Hohai University and Nanjing Municipal Solid Waste Management Office to successfully develop the technology of processing waste concrete into lime-fly ash macadam as the base material of municipal roads. The technology is that the transported waste concrete is crushed and mixed with concrete with different particle sizes in proportion, and lime, fly ash and special additives are added to generate lime-fly ash macadam. Using this material as road base can completely meet the requirements of road bearing capacity.

A company in Taiyuan also uses three processes, namely, crushing various construction wastes, adding active ingredients and stirring molding, to make various standard bricks, road bricks and building blocks. Moreover, these products have very good thermal insulation performance, with the characteristics of gradually increasing strength with time, small shrinkage, non-toxic and pollution-free, and good durability. This technology has the advantages of short technological process, no burning, less investment, quick effect and no secondary pollution, and has good social and economic benefits, which has created a new production channel for building bricks and played a certain role in promoting the environmental protection of building materials industry.

Three suggestions

3. 1 Establish a unified management organization for construction waste.

At present, the construction waste is basically who works and who manages it, who can load it, who can transport it and who can dismantle it, and it is in a disorderly state. Dust and road garbage cannot be eradicated, making urban sanitation an empty talk. In the process of garbage utilization, such as stacking, reprocessing, design, norms and corresponding laws and regulations are gone. Even if you want to use it, it's useless. Therefore, an organization should be established to manage this work in a unified way, and unified management, unified planning, unified field construction and processing, unified information dispatching, unified planning, design and utilization norms and relevant regulations should be implemented. Specifically, the following aspects should be carried out:

(1) Set up a professional management organization and Xi 'an Construction Waste Management Office, with four sub-stations. It is bounded by east, west, south and north street, and extends outward to become a section under the jurisdiction of four substations. Responsible for building demolition, garbage removal, stacking, treatment, utilization and scheduling in the area under its jurisdiction. The management office is responsible for the establishment and certification of the system, the demolition method, the demolition of the team's vehicles, the establishment and distribution of the demolition professional team, the establishment of the stacking yard and the establishment of the garbage disposal equipment.

(2) Establish a professional demolition team to turn the demolition work into one-stop production and prevent the disconnection of the newly demolished. So as to classify and pile garbage, make full use of useful substances and avoid dust generated by repeated excavation. This can also prevent all kinds of accidents and provide guarantee for the creation of urban sanitation.

(3) Formulate processing and utilization specifications, such as particle size, content, ratio, strength, design and application scope of related harmful substances. , to provide a guarantee for reuse.

(4) Establish the information network of demolition transportation, and all demolition transportation shall be handled by professional organizations. To understand urban construction planning, it is necessary to know the direction of each demolition site, so that garbage and waste soil can be reused.

(5) Make plans in time according to the information provided, such as stacking, processing, factory setting, transportation, earthwork allocation plan, etc. Delineate the stacking area and formulate the earthwork utilization plan.

(6) Establish a processing and utilization plant, further classify the collected garbage according to the use requirements, and generate semi-finished products, such as brick ballast, brick ballast concrete yard, lime-fly ash macadam (brick and concrete stone), baking-free brick, etc. , for the use of engineering units.

(7) Formulate regulations on the management of urban building demolition, so as to make the management of urban building demolition on a professional and orderly track and create a harmonious social environment for Xi citizens.

(8) Establish research institutions to provide scientific basis for the reuse of construction waste and expand the scope of utilization.

3.2 Study the economic and effective ways of reuse

At present, many countries have a lot of experience in the reuse of construction waste. Based on the actual situation of Xi city, the author puts forward the following two ways and analyzes their economic benefits.

(1) is suitable for roads. Subgrade: earthwork replacement and soft foundation treatment; Pavement: isolation layer, subbase (lime soil), base (limestone, gravel), recycled asphalt pavement.

(2) Used in building engineering: soil foundation (lime soil), masonry slag concrete and baking-free brick.

Economic benefit analysis:

(1) Taking the production of ballast subgrade cushion (isolation layer) as an example, it is 12 yuan -m-3. Calculated by construction waste 1/3, the annual economic benefit can reach14.88 million yuan.

(2) Taking the production of pavement subbase materials, such as broken bricks and concrete, as 18 yuan -m-3 and construction waste as 1/3 as an example, the annual economic benefit is 22.32 million yuan.

(3)60 yuan -m-3 is based on the production of lime-fly ash macadam masonry materials for pavement, and the annual economic benefit is 74.4 million yuan according to 1/3 construction waste.

(4) Using recycled asphalt can save 100 yuan per ton and create a value of 67.53 million yuan.

(5) The production of baking-free bricks and other materials needs to be investigated.

In a word, the utilization of construction waste is a work for Xi. It is estimated that the annual economic benefits will reach 654.38+0.7 billion yuan in recent years.

4 conclusion

(1) Through investigation and study, it is concluded that the annual garbage output in Xi 'an is: building 362.67- 10 4m3, municipal1000-104m3, subway 8.00- 10 4m3, *.

(2) It is suggested that Xi municipal government set up an organization to manage this work in a unified way, and implement unified management, unified planning, unified on-site construction and processing, unified information dispatching, unified planning and design, and carry out corresponding scientific research.

(3) Combined with the actual situation of Xi, the specific ways of using construction waste for roads and industrial and civil buildings are put forward.

(4) According to the analysis, the annual economic benefit of recycling construction waste in Xi City can reach 654.38+700 million yuan.

For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd