A first simple method is visual that can be used for coarse materials, but sieving a sample following by sedimentation method could separate the fine and very fine materials. Finally if you intend to know exactly some fine materials, there are chemical tests that can help you to identify for example cement, lime, plaster and others .

As suggested by many researchers, composition of construction demolition wastes can be roughly identified by segregating various types of wastes, clearly visible by naked eye, such as concrete, mortar, steel and nonstructural fixtures such as window and door panels, frames and grills. However, composition of the broken concrete pieces can be determined by modern analysis such as X-ray fluorescence spectrometry. Other advance characterization techniques can be used for further characterization such as pores, particle sizes and morphology. Hope you are conversant with these terms and necessary facilities are required in your institute/laboratory for carrying out these analyses---Thanks

If you you want to quantitatively determine the constituents materials of CDW, I suggest following this standard test ( BS EN 933-11:2009) . The test consists of hand sorting of particles from a test portion of coarse RA from CDW into a list of constituents. The proportion of each constituent in the test portion is then determined and expressed as a percentage by mass, except for the proportion of floating particles which is expressed as a volume. Hope this helps.

Thanks

You need to survey the demolition works and produce a works program so that materials can be sorted for reuse recovered or isolated. Good planning is key to successful demolition

A surveyor with Demolitions and Recovery Experience will do this work in a day or so even for the largest and complicated building. Of course building systems differ all over the world a rough guide to Central Europe

Planning

You have all the time you need to process and value engineer demolition because the findings of the survey is the basis for the tendering and completion of the demolition works. There is plenty of time during tendering to manage the hazardous materials and award demolition in or out of the main works

Environmental & Green

Dangerous and Hazardous Material - Removal and Disposal

Green Works - Removal, Recovery, Relocate Re-use [including valuable top soils]

MSW & Waste

Remove non fixed items used in FF&E and fit our ideally sort and shred and recover or isolate as needed. Sort soft plastics, metals, wood, and other as best you can

Recoverable Building Systems

Strip out team removes and relocates the materials to their dedicated sorting hard standing. Often Bricks and Lintels are recovered.

Anything left over and a by produce is MSW & Waste or recoverable structural systems. Recoverable Building Systems are usually sold or donated for reuse

Recoverable Structural Systems

Surveyor indicates usable hard works e.g. low density and other materials so they can be demolished and crushed to ideal tolerance for reuse for example non structural backfill or structural reuse in sub layers of roads etc.

Using a trommel during crushing and processing segregates aggregates and fines, magnets remove steel and other metals. Aggregates can include broken glass, tiles ceramics etc

Substantially I agree with the other authors' answers. In particular, with Luiz Pereira de Oliveira.

It seems that the most toxical components would be old paint, on walls, wooden parts, metallic elements, especially when those paints contains lead. Samples from the waste should be analysed by some competent laboratory and treated according to local legislation. You may see : http://www.who.int/phe/health_topics/lead_campaign_2013/fr/index.html#

Any answer will be site specific and vary with time. First, you need to ask why you need the information and what is the use for the information.

Often the purpose is to design a recovery system for part of the waste stream and that can be estimated by knowing the weight being disposed of and by hand sorting samples into desirable categories. The categories would be determined by your objectives. For example, recovery and recycle of road base material may look for concrete, brick and fired ceramics, rock, sand and related material that can be fed into a crusher to produce road base and separately asphalt materials that can be crushed, reheated with more tar added for road surfaces.

If we consider construction and demolition waste as all the waste generated in the activity, we have to consider too oils, leaked fuels, equipment's share parts used, etc.

There are a lot of publications for quantity and composition predictions in a construction work.

How to determinate the composition of a mixed waste?. I'm completely agree with Mr. Pereira and Mr Bhagwanjee.

Take large sample of waste, and segregate it physically to determine the physical components (paper, cans, aluminum, wood), weight each material and divide the wt on the total wt of sample to determine the ratio , then take sample form the sand and analyse it for chemical component if required......

@Luiz Pereira de Oliveira: Thank you for your good ideas, but: the first method just qualitative, not quantitative and not suitable for industrial recycling process. The second (seiving) also not exactly because the most recycled concrete/mortar aggregates contain much or litle atachement mortar or binder or bunrt brick. The third method (chemical test), I think is good but I don't know how in detain? chemical compositions of cement, concrete, aggragate are quite similar.

@ Khaleel Younis: do you have the electronic of BS EN 933-11:2009? because I am Vietnamese so can not access the standard.

Dear Tong Kien: When the question is to improve the industrial recycling process, in my point of view, the best action to replace the qualitative visual procedure is to always give priority to a selective demolition. In RCD plants that I know, the only usual system (viable economically) is the separation of RCD components by sieving. When the identification of incompatible materials is necessary (ex: cement/gypsum), there are a lot of chemicals methods that could be employed. But, the technical and economical viability of any industrial recycling process is very dependent of a selective demolition otherwise we are in the utopia domain that is not a “beach for engineers”.

I would like to suggest you read the following paper

Environmental impacts of the UK residential sector: Life cycle assessment

of houses

Rosa M. Cuéllar-Franca, Adisa Azapagic, Building and Environment 54 (2012) 86-99

We are looking to find a relatively small scale shredder for furniture and other waste separated by building users and left outside their apartment at MSW collection centres in large communities in Poland and starting with the Capital Warsaw. The same set up could quite easily visit construction sites and collect sorts. However as the MSW regulations are a little confused here existing MSW sources are for sure the lowest hanging fruit

Waste is wood furniture [loose description] Christmas, packing cases trees etc, the operators are under no obligation to remove all of this sort from any destination they can skim

We are looking then for a mobile shredder one that would reduce the bulk into wood chip in transit and preferably one which could process on the go so it can be delivered directly to a PowerCan 200 unit gasification unit as feedstock www.powercan200.com we could be interested in and R&D or a bespoke project providing it is at least tested.

The ideal size would carry a payload of shredded material of 4 tons [approximate] and on one non articulated vehicle

Stiff plastics present little problem but we must be able to remove the metal either in the shredding process or at the feedstock centre because we cannot gasify metals or minerals, we are also keen to find a process which does not create too many fines as this too would choke the system

If you have any experience or if you are in a similar project and wish to network please contact me directly and welcome to join our new closed discussion group for PowerCan 200 on LinkedIn

Dear Tong, you can find some ways to determine the composition of CDW mixtures in my publications and papers. If you have composites, you should distinguish between liberated and unliberated aggregates. For processing of mixed CDW, there are already technical solutions, e.g. sensor-based sorting devices. If you have any quesions, please contact me. We are working for the German project consortium "Closed-material cycles in masonry constructions". Mirko