CONSTRUCTION AND DEMOLITION WASTE RECYCLING

The environment-related problems, which are one of the necessary conditions for the continuation of life that contains everything around human being, are increasing gradually and threatening both nature and humanity. Natural resources are decreasing every day due to the increase in world population and consumption habits. In recent years, environmental problems have been experienced due to global climate changes with the rapid decrease of natural resources.

For this reason, it is obligatory to reduce the consumption of materials and to use the natural resources efficiently by  the qualified wastes. Therefore, is very important in terms of conservation and efficient use of natural resources.

Construction industry is one of the sectors where raw materials are most consumed. The construction sector tries to minimize inputs in manufacturing processes, reduce the use of raw materials and energy consumption as much as possible .

Therefore, it is necessary to reduce waste generated from construction and demolition activities for effectively and efficiently reducing waste problems.

Waste Minimization Techniques

While serious pollution generated from construction activities, a comprehensive construction waste management is urgently needed on every construction site. It is of great importance to structure ways for minimizing waste generation is seen as the most favorable solution to waste problems of any kind. Indeed, it should be made compulsory that every construction company should enact construction waste management plan tailored to its particular mode of business so that every personnel from the management to the operational level can head for the same goal of construction waste management.

Economic and environmental benefits to be gained from waste minimization are important, since it will benefit both the environment and cost reduction. The economic benefits of waste minimization include possibilities of selling specific waste materials and removal from sites of other waste at no charge or reduced cost, with a subsequent reduction in materials going to landfill

Waste minimization is any techniques, process or activities which avoids, eliminates or reduces waste at its source or allows reuse or waste for benign purposes. There are many possibilities for disposing waste from construction and demolition activities, from to incineration and landfilling. Prior to considering various options that could be utilized, a hierarchy of disposal options needs to be captured into six levels, from low to high impacts, namely, reduce, reuse,  compost, incinerate and landfill.

A huge amount of construction and demolition materials are discarded at construction and renovation sites. The materials that can be beneficially nto new products are:

1.Demolition Waste

• Asphaltic  paving
• reinforcing steel
• Brick
• masonry units
• Wood paneling
• Structural and miscellaneous steel
• Roofing
• Windows

2.Construction Waste

• Masonry and CMU
• All untreated wood, including lumber and finish materials
• Wood sheet materials
• Wood trim
• Metals
• Roofing
• Insulation
• Carpet and pad
• Gypsum board
• Unused (leftover) paint
• Piping
• Electrical conduit

Benefits of Materials

Reduction on Environmental Impact

“Using scrap steel and iron rather than virgin products results in an 86 percent reduction in air pollution and a 76 percent reduction in water pollution.”
The quantity of steel and iron wastes was produced in a bulk amount in the construction industry. The continuously production and application of the new steel and iron in the construction industry make the people lazy and omit to do theon steel and iron wastes. Actually, the new steel and iron production will bring a lot of negative impact not only to the construction industry but also to the general public. It will cause the high percentage of pollution to the air and water condition. Consequently, the environment will be influenced seriously by the bulk quantity of new steel and iron production and will affect the health of the people.
However, this problem can be solving easily by the way of doing theon steel and iron wastes.  of steel and iron is a need for the construction industry. It is the best method to reduce the quantity of steel and iron wastes and also reduce the requirement of the new steel and iron production. Therefore,is important for the construction industry to have a non-polluted air and water condition in order to have a healthy and green environment. Furthermore,minimise the environmental impact by reduce the extraction and manufacturing processes for production of new materials.
“can prevent emissions of many greenhouse gases and water pollutants.” Besides that, also can avoid the additional discharge of greenhouse gases and water pollutants in construction industry. The of construction wastes can reduce the need to extract raw materials and produce new material in order to reduce the production of greenhouse gas emissions and water pollutants.

o Cost Saving

The of construction waste can save the overall construction project cost. The materials cost can be decrease substantially through theby the substitution from the new materials to  materials in the construction industry. In addition, also decrease the disposal and transportation cost for the construction wastes. Since most of the construction wastes is going to be, thus the amount of waste is reduce so as to save the additional disposal and transportation cost. Furthermore, save the construction cost by using the construction wastes which will otherwise be lost to landfill sites.

Materials Saving

can save the construction materials by reduce the needs of new resources that use to produce the new materials. The quantity of supply for new construction materials can be reduce since most of the construction wastes are and reusable in construction industry. Therefore, the of construction wastes can reduce the needs of new resources in order to achieve the materials saving.

Energy Saving

“Recycling aluminium saves 95 percent of the energy used to produce it from virgin products.” The construction industry also facing the problem on the aluminium wastes. In the construction industry, the aluminium wastes are from the broken roller shutter, window components and door frame. Since the aluminium was difficult to be dissolve by the land, it will produce the problem of disposal on it. In addition, it would consume a lot of energy to product the new aluminium product. It is because the aluminium is a soft metal that need to be forming by the high temperature thus will consume a lot of energy on new production. However, there is a ways to solve these problems which is recycling of aluminium wastes. During recycling, re-melting aluminium requires only 5 per cent of the energy that is use to produce primary aluminium. Recycling aluminium is the most efficient method to reduce the demand of new production and thus achieve the energy saving. Generally, the production cost for recycled aluminium will be cheaper than the primary aluminium because it is less energy used during production.

Conserves Landfill Space

Recycling of construction and demolition waste can also reduce the need for new landfills. Recycling can conserve the landfill space since most of the construction waste is going to be recycling and landfills is only for small amount of waste in construction industry. In addition, recycling reduce the need for landfills in order reduce the associated cost for landfills.

Creates job

Recycling also creates the employment opportunities and economic activities in construction industry. Since the construction industry have a lot of recycling works which is require to be carry out by manpower, therefore it create more opportunity for people to acquire the job.

Disadvantages of Recycling

High upfront capital costs

Recycling is not always cost-effective. Building up a new waste recycling unit takes up a lot of capital. The accompanying costs include buying different kinds of utility vehicles, upgrading the recycling unit, waste, and chemical disposal and schooling the locals by initiating useful programs and seminars.

Recycling sites are always unhygienic, unsafe and unsightly

Go to any waste recycling site, and you will almost always stumble upon unhygienic, unhealthy and unsightly conditions. Locations where every manner of waste is piled provides a nice ground for the formation of debris and spread of infectious diseases. The harmful chemicals from these wastes can also be dangerous. On top of causing massive pollution, the whole recycling process poses health risks for dedicated individuals responsible for recycling these waste products. Also, if such waste products come into contact with water, results in the formation of leachate that ends up polluting water bodies, not to mention drinking water.

Products from recycled waste may not be durable

The quality of products manufactured from recycled waste may not be on par regarding quality. These kinds of products are almost always made of trashed waste material collected from mountains of other waste materials that have been overly utilized and fragile. This makes products of recycled waste less durable and low priced.

Recycling might not be inexpensive

Sometimes, recycling waste may not be less costly as most people think. At times, a need arises to establish another waste recycling unit for processing. This will only drive up the costs related setting up the new unit or upgrading the processing facility, collection of waste materials, acquiring different utility vehicles, educating residents by organizing seminars and other programs etc.

Recycling is not widespread on large scale

Although recycling plays a bigger role in reducing the rate of pollution, the process has not been widely embraced and developed. Unfortunately recycling still is just a small part of long-term success. Recycling is mostly common in schools and homes and has not hit a bigger milestone, for example, it has not been wholly used at local industries or holistically at a global stage. Conservation of trees at school is incomparable to the massive destruction of trees and oil spills happening at industrial levels. After juggling the advantages and disadvantages of recycling, an individual can wisely take significant steps involved in recycling process. Knowing the effects of recycling is vital to a larger degree that if carried out effectively, can bring immeasurable benefits to the environment and humans

References:

- Conserve Energy Future-Advantages and Disadvantages of Recycling
- İnşaat Endüstrisinde Geri Dönüşüm Çalışmalarının Geliştirilmesi ve Ekonomi Üzerine Etkileri-Asst. Prof. Dr. Fatih Kürşat Fırat (Aksaray University, Turkey) Mr. Fahri Akbaş (Aksaray University, Turkey)
- İnşaat atıklarının asfaltta geri dönüşüm malzemesi olarak kullanılması- Dr. İbrahim Sönmez
- Rate of Reusable and Recyclable Waste in Construction Vivian W.Y. Tam- School of Engineering, University of Western Sydney, Penrith South DC, NSW 1797, Australia
- United State Environmental Protection Agency-EPA-Construction Waste Management Section 01 74 19
- https://www.ukessays.com/dissertation/literature-review/construction/study-of-recycling-of-construction-materials.php