Peter Rem

Peter Rem
Delft University of Technology | TU · Department of Structural Engineering

About

108
Publications
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Publications

Publications (108)
Article
To upcycle End-of-Life (EoL) concrete from demolished buildings, it is essential to efficiently identify the different materials that may contaminate it. The precise identification and classification of materials and contaminants are vital processes for in-line quality inspection of recycled concrete aggregates transported on a conveyor belt. In th...
Article
Full-text available
In this paper electromagnet layouts are presented that generate a magnetic field with a magnitude gradient that does not vary significantly in a horizontal plane but decreases monotonically with the vertical height above the magnet. Such a one-direction magnetic field gradient is a specific requirement for magnetic density separation, a novel recyc...
Article
Full-text available
This paper discusses the optimum layout of coils of a superconducting magnet system for Magnetic Density Separation (MDS). MDS is a novel separation technology that combines a vertical magnetic field gradient with a ferrofluid to separate mixtures of non-magnetic particles based on their mass density. The MDS process can separate more than two type...
Article
Can random deposition create dense non-overlapping material feeding? The question is very fundamental for the research of particle packing, while the answer is of great importance for any industrial process that applies single object operation. To gain an insight into this issue, we studied the overlap problems of convex particles in the manner of...
Article
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Currently, natural resources are consumed at an alarming rate than their production (United Nations Environment Programme, 2014). This imposes unprecedented pressure on the environment. The problem seems to get worse with the present increase in population and demand for infrastructures. To alleviate these and other related problems, a circular app...
Article
Full-text available
This study focuses on formulating the most sustainable concrete by incorporating recycled concrete aggregates and other products retrieved from construction and demolition (C&D) activities. Both recycled coarse aggregates (RCA) and recycled fine aggregates (RFA) are firstly used to fully replace the natural coarse and fine aggregates in the concret...
Patent
A separation apparatus is disclosed, comprising: a layerizer arranged to bring a group of particles in a layer on a transport surface with a constant spatial relation of the particles relative to each other in the layer; an identifier arranged to identify particles in the group of particles that have a specific property; a separator arranged to sep...
Patent
Full-text available
A separation apparatus is disclosed, comprising: a layerizer arranged to bring a group of particles in a layer on a transport surface with a constant spatial relation of the particles relative to each other in the layer; an identifier arranged to identify particles in the group of particles that have a specific property; a separator arranged to sep...
Article
Full-text available
An innovative route for plastics recycling is proposed, based on a combination of a logarithmic sorting process and colour plus high-resolution near-infrared (NIR) sensors. Although counterintuitive, it is shown that such a technology could sort clean flakes from rigid packaging waste into a very large number of different plastic grades with modest...
Article
To prevent eutrophication of surface water, phosphate needs to be removed from sewage. Iron (Fe) dosing is commonly used to achieve this goal either as the main strategy or in support of biological removal. Vivianite (Fe(II) 3 (PO 4 ) 2 * 8H 2 O) plays a crucial role in capturing the phosphate, and if enough iron is present in the sludge after anae...
Chapter
End of Life (EOL) concrete fines, that is often 0–4 m, is one of the massive by-products of concrete recycling. Using this fraction into new concrete is detrimental, due to its high water absorption and mixed contaminants. Although the construction sector is to some extent familiar with the utilization of the coarse fraction of crushed concrete, at...
Article
This paper proposes a new value-based indicator to assess the performance of actors in the supply chain in terms of resource efficiency and circular economy. Most of the methodologies developed so far measure resource efficiency on the basis of the environmental burden of the resource relative to the value of output. However, the key point of circu...
Conference Paper
After a decade of intensive research into the recycling of End-of-Life (EOL) concrete into high-grade new concrete, largely supported by funding from the European Commission, it appears that a circular economy for concrete is techno-economically feasible. A collection of advanced technologies, in particular smart demolition for clean mono-flows of...
Conference Paper
The ever-increasing interest on sustainable raw materials has urged the quest for recycled materials that can be used as a partial or total replacement of fine fractions in the production of concrete. This paper demonstrates a modelling study of recycled concrete waste fines and the possibility of turning them into active constituents for the produ...
Article
Full-text available
Enormous amount of Construction and Demolition Waste (CDW) are yearly generated in Europe and the predominant material constituent is concrete. Despite the urgency of creating a sustainable solution for End Of Life (EOL) concrete waste treatment, there has not been a large driving force for recycling it into prime grade materials. The C2CA concrete...
Article
In order to move towards a more sustainable development, it is necessary not only to minimize the use of materials in the design stage and to find new materials as alternatives to nonrenewable ones (e.g. optical fiber instead of copper, biopolymers instead of polymers from oil) but also to reclaim as much as possible material value through effectiv...
Article
In recent years recycling is gaining a key role in the manufacturing industry. The use of recycled materials in the production of new goods has the double advantage of saving energy and natural resources, moreover from an economic point of view, recycled materials are in general cheaper than the virgin ones. Despite of these environmental and econo...
Article
An innovative recycling process, based on magnetic density separation (MDS) and hyperspectral imaging (HSI), to obtain high quality polypropylene and polyethylene as secondary raw materials, is presented. More in details, MDS was applied to two different polyolefin mixtures coming from household waste. The quality of the two separated PP and PE str...
Article
Polyvinylchloride (PVC) is one of the most produced polymers in Europe, with a share of 11% in terms of mass (8 million tons) of total polymer consumption, but in 2010 only 5% of the total PVC production came from recycled materials, where other polymer recycling achieves a level of 15% on average. In order to find an innovative process to extract...
Article
Full-text available
Robotically Driven Construction of Buildings (RDCB) is an exploration into design to production solutions for robotically driven construction of buildings initiated by the faculties of Civil Engineering and Architecture, TU Delft and Architecture, TU Eindhoven and implemented 2014 within the 3TU Lighthouse framework. The aim of was to involve the d...
Article
Recycling End of Life (EOL) concrete into high-grade aggregate for new concrete is a challenging prospect for the building sector because of the competing constraints of low recycling process cost and high aggregate product quality. A further complicating factor is that, from the perspective of the environment, there is a strong societal drive to r...
Article
Full-text available
Robotically Driven Construction of Buildings (RDCB) is an exploration into design to production solutions for robotically driven construction of buildings initiated by the faculties of Civil Engineering and Architecture, TU Delft and Architecture, TU Eindhoven and implemented 2014 within the 3TU Lighthouse framework. The aim of was to involve the d...
Article
Introduction Existing Mechanical Processes Project Description Results Conclusions Acknowledgements
Article
Polyvinyl chloride (PVC) is one of the most commonly used thermoplastic materials in respect to the worldwide polymer consumption. PVC is mainly used in the building and construction sector, products such as pipes, window frames, cable insulation, floors, coverings, roofing sheets, etc. are realised utilising this material. In recent years, the pro...
Article
The paper presents the research made on the FP7 project „Magnetic Sorting and Ultrasound Sensor Technologies for Production of High Purity Secondary Polyolefins from Waste” in order to develop a magnetic fluid equipment for sorting of polypropylene (PP) and polyethylene (PE) from polymers mixed waste streams. Because both PP and PE float in water,...
Article
The aim of this study is to establish the feasibility of the MDS technology, for production of secondary polyolefins from polymer waste. The article presents: the description of business, the project overview, the operational plan, the flowchart of the process, the energy consumption, the investment costs, the variable operating costs, the fixed op...
Article
Post-consumer steel scrap is often handpicked for contaminants, such as copper, to meet the specifications of steelmakers. If the hand sorting capacity exceeds 20 t scrap/h, the efficiency generally becomes problematic, leaving 50% of the copper contaminants in the steel product. In response, new technologies are emerging that facilitate hand sorti...
Conference Paper
Full-text available
The recycling of end-of-life concrete into new concrete is one of the most interesting options for reducing worldwide natural resources use and emissions associated with the building materials sector. The production of the cement used in concrete, for example, is responsible for at least 5% of worldwide CO2 emissions. Onsite reuse of clean silica a...
Article
Full-text available
Liquid Density Separation (LDS) increases the germination quality of a sub-batch of seeds within a seed batch. A novel, alternative method for separating seeds by density is Magnetic Density Separation (MDS). In this paper, a comparison is made between LDS and MDS. It is also shown that MDS can improve germination quality by separating seeds contin...
Article
Full-text available
The bottom ashes resulted annually from the incineration of municipal solid waste in Europe contain about 400,000 tonnes of metallic aluminium and 200,000 tonnes of heavy non-ferrous metals, such as copper and zinc. Efficient re-covery of this non-ferrous metal resource requires state-of-the-art separation technologies and a continuous feedback of...
Article
The industrial implementation of Magnetic Density Separation (MDS) in the recycling of raw materials requires more than just the science of understanding why it works ('know-why') and the technology of how that can be accomplished ('know-how'). In addition, detailed knowledge of the market for streams of end-of-life products (supply side) and the m...
Article
Full-text available
The efficient large-scale recycling of plastic waste is of increasing interest from an ecological and economic point of view but it represents a goal that has yet to be achieved by the recycling industry. The W2Plastics project aims at a fundamental change of the present status of plastics recycling by creating a breakthrough technology for the rec...
Article
Full-text available
The efficient large-scale recycling of plastic waste is of increasing interest from an ecological and economic point of view but it represents a goal that has yet to be achieved by the recycling industry. European project W2Plastics (FP7) aims at a fundamental change of the present status of plastics recycling by applying the Magnetic Density Separ...
Article
The cut-density of sink-float separations with water-based magnetic liquids linearly depends on the magnetization of the process liquid. The control of the magnetization of the liquid, by means of measurement followed by extraction of water from the process liquid by membranes or mixing with water or concentrated magnetic liquid, is therefore a cri...
Article
The accuracy of sink-float separations in water-based media such as Magnetic Density Separation is compromised by tiny air-bubbles attached to the surface of hydrophobic materials in the feed. Separations of plastics mixtures with accuracy better than 10 kg/m 3 require a total elimination of air-bubbles by pre-wetting the surface of the feed partic...
Article
Abstract of WO 2009108053 (A1) A method for separating seeds of different densities in a process stream, wherein the seeds are introduced into a magnetic process fluid for the formation of the process stream, which process stream is subjected to a magnetic field for the realization of a density stratification in the process stream, such that the in...
Article
Full-text available
The European annual consumption of plastic materials has increased from 24.6 Mtons in 1993 to 39.7 M tons in 2003 and it is likely to keep growing. Europe is faced with the challenge of managing millions of tons of waste plastics. At the same time, polymer recyclers and manufacturing industries do not find enough secondary polymers of consistent qu...
Article
Literature data show that in general, plastics produced through the mechanical recycling route involve less carbon dioxide emission than when produced from crude oil. A review of readily available data shows that road transport of untreated waste plastics account for a significant portion of the carbon dioxide emission generated during recycling. T...
Article
In view of the predicted diamond shortage in 2010, a number of innovative processes have been proposed recovering <2 mm diamonds which are currently lost in tailings. One of these innovations is based on the ferrohydrostatic separation (FHS) as developed by De Beers. This new method, known as magnetic density separation, creates an apparent density...
Article
With the increasing growth of incineration of household waste, more and more aluminium is retained in municipal solid waste incinerator bottom ash. Therefore recycling of aluminium from bottom ash becomes increasingly important. Previous research suggests that aluminium from different sources is found in different size fractions resulting in differ...
Article
Full-text available
Municipal solid waste incineration (MSWI) bottom ash contains economically significant levels of silver and gold. Bottom ashes from incinerators at Amsterdam and Ludwigshafen were sampled, processed, and analyzed to determine the composition, size, and mass distribution of the precious metals. In order to establish accurate statistics of the gold p...
Article
Polyolefin fractions are often end fractions resulting from the recycling of end-of-life consumer products. Polypropylene (PP) and polyethylene (PE) are present in such fractions as a mixture. For instance, the ratio of PP and PE in car scrap is 70:30 on average. However, the grade of the PP and PE should typically be better than 97% to be reused a...
Article
Polyolefins can be considered as one of the most important polymers for consumer goods being polyethylene (PE) and polyropylene (PP) the most commonly utilized. Even if post-consumer wastes could be considered as a good resource of polyolefins, their recovery and recycling is very low. The reason can be mainly attributed to the complexity of these...
Article
Post-consumer wastes, such as WEEE (Waste from Electric and Electronic Equipment), HW (Household Waste) and ASR (Automotive Shredder Residue), can be considered an important resource of polyolefins. Such wastes are composed of a complex mixture of different materials. Recoverable high purity polyolefins are difficult to select mainly for two reason...
Article
Abstract of WO 2009123452 (A1) The invention relates to a separation-apparatus (1) for separating from a particle-stream (4) at least a first fraction with particles (3) of a first group of dimensions, and a second fraction with particles (3) of a second group of dimensions, comprising an infeed-device (2) for the particle-stream (4), a rotatable d...
Conference Paper
The composition of municipal solid waste (MSW) influences the incineration process. The high heat value of some materials contained in the waste and their moisture content affects the capacity of the process. In particular, the plastics presence negatively affects the incineration process: an increase of calorific value means a reduction of the cap...
Article
Abstract of corresponding document: WO2006126872 The invention relates to an apparatus for the generation of parallel beamlets, comprising a source for particles or radiation, a collimator and, placed between the source and the collimator, a beam splitter for dividing the beam from the source into beamlets, wherein a first macrolens is provided bet...
Article
The Magnus effect, i.e., the lift force, which is observed when a spinning body moves through a fluid at right angles to its axis of rotation, can be used to separate metal particles from a mixture. The necessary selective rotation of the metal particles is brought about by the action of a fast-spinning magnet rotor, of the same kind that is used f...
Conference Paper
Full-text available
Incineration reduces the mass of municipal solid waste (MSW) by 70% to 80%, and it reduces the volume by 90%. The resulting fractions of the incineration are bottom ash, fly ash and flue gas residue. Bottom ash is by far the largest residue fraction. About 1.1 million tons of bottom ash are produced in the Netherlands and about 20 million tons in E...
Article
Granular wastes have negative effects on the environment due to contamination. On the other hand, stony components in granular wastes have a potential good perspectives for utilization in civil engineering works as secondary raw building materials. To reuse such materials without environmental risks, all contaminants must be removed or reduced to a...
Article
Worldwide construction and demolition waste (CDW) is currently dumped. To close the building cycle and the building materials cycle by recycling CDW in high technical applications, the technical quality of stony materials must be improved. For this purpose, concrete rubbles and brick rubbles, the two major stony constituents of CDW, should be separ...
Article
Full-text available
Market-driven industrial recycling can only be optimized if recycling companies adopt a comprehensive overview and are able to combine and integrate economics with the system engineering of interconnected recycling systems. To succeed in this endeavor, the companies require detailed knowledge of the interaction between the process/quality control,...
Article
Full-text available
Recovery of fine non-ferrous metals from waste streams is a notoriously difficult problem in eddy current separation technology. Existing processes either have a low capacity or an incomplete recovery for particle sizes below 5 mm. In a new process, the particles are fed slightly wet to make them stick to the surface of the conveyor belt. The actio...
Article
Full-text available
Separations by density, such as the separation of non-ferrous scrap into light and heavy alloys, are often realized by means of heavy media. In principle, kinetic gravity separations in water can be faster and cheaper, because they do not rely on suspensions or salt solutions of which the density must be tightly controlled. Test results of a protot...
Article
In the summer of 2002, an experimental wet process was tested on 116 tons of bottom ash from the Amsterdam MSWI. The aim of the pilot was to demonstrate the feasibility of combining a washing step for improving the environmental quality of the ash with extensive metals recovery to meet the cost of the treatment. Bottom ashes from the incineration o...
Article
The trajectories of real scrap particles processed with an eddy current separator are compared to computer simulations to investigate the effects of particle shape and particle–particle interaction, effects that are difficult to catch in a purely theoretical model. The results show that the primary particle parameters are size, conductivity and ini...
Article
Recovery of non-ferrous metal particles from a stream to yield non-ferrous metal-enriched and metal depleted fractions involves putting the stream onto a conveyor belt (1) as a mono-layer such that with the help of water at least the non-ferrous metal particles get adhered to the belt; subjecting the moist mono-layer to magnetic field rotating in t...
Article
Separation of particle fraction from particle stream in a fluid e.g. aqueous liquid medium under gravitational force based on difference in vertical velocity involves passing the fluid and particle in horizontal direction defining relative direction of movement; collecting first particle fraction and second particle fraction in respective collectiv...
Article
Full-text available
This paper describes a new type of eddy-current separator. It separates electrotechnical wastes containing metallic particles with dimensions less than 5 mm. The separator, a so-called single-disk eddy-current separator (SDECS), consists of an inclined horizontal rotary disk covered with permanent magnets, alternately N-S and S-N oriented, directly...
Article
Galileo was the first to analyze the motion of spheres rolling down an inclined surface. Since then, Coulombs law of dry friction has covered the case of sliding particles. However a particle that is not round can still roll, although in a way that is essentially different from the motion studied by Galileo. Instead of keeping contact with the surf...
Article
Abstract of WO 0121317 (A1) The invention relates to a method of separating particles in a fluid medium, wherein the particles have a density lower than that of the fluid medium. According to the invention the particles are subjected to an up and down moving flow of the fluid medium, whereby a barrier is present above the particles restraining said...
Article
The difference between rolling and sliding motion is a good basis for the separation of particles. The principle has already been applied in various shape separators. In this paper, experiments on a new rotating cone separator are presented, which is especially designed to process recycled materials. A simulation model is used to first characterise...
Article
Full-text available
This paper presents a method for separating small metallic nonferrous particles from two-component nonferrous mixtures using, a new type of dynamic eddy-current separator with permanent magnets. The so-called inclined drum eddy-current separator (IDECS) consists of an inclined vertical rotary drum covered with permanent magnets, alternately N-S and...
Article
Newly developed software can predict the essential characteristics of the sand product resulting from the ex-situ washing of contaminated soil, dredging sludge or breaker sand. The system was designed for the Dutch situation and it works on the basis of readily available information. The primary output of the system is an assessment of the reusabil...
Article
The Magnus effect is the lift force on a body moving through a fluid as a result of the rotation of that body. In theory, the Magnus effect can be used to recover small non-ferrous metal particles from dry bulk streams. The Magnus separation process would consist of passing a feed stream next to a fast-spinning magnet in order to create a selective...
Article
With the rapid growth of the electronics industry and an ever-growing environmental awareness world-wide, an environmentally sound and economically viable management system for end-of-life (EOL) electric and electronic equipment (EEE) is of great importance for sustainable development. Traditional recycling and processing of EOL electronics directe...
Article
With the rapid growth of the electronics industry and an ever-growing environmental awareness world-wide, an environmentally sound and economically viable management system for end-of-life (EOL) electric and electronic equipment (EEE) is of great importance for sustainable development. Traditional recycling and processing of EOL electronics directe...
Article
Separability and separation mechanisms of small particles in modern rotating type eddycurrent separators (ECSs) were discussed in Part I. In order to address problems associated with this design concept, a number of novel ECSs, each with a unique design, have been developed. Part II reports on investigation into the separability and separation prin...
Article
Reusing materials in the post-consumer phase of a product is very important; however, it is often difficult to separate the metals, resulting in a scrap that is high in impurities and limited in application. To prevent the mixing of scrap, separation at the source is required. Recently, several techniques for separating nonferrous metals have becom...
Article
The kinetics of screening for differently shaped particles can be used to separate particles according to their size, as well as to their shape. During a batch screen experiment the number of particles on the screen as a function of time was counted by using a CCD-camera and image analysing software. The screening kinetics of cylindrical particles...
Article
Particle trajectories of the newly-developed two-drum eddy current separators are simulated by the ECSIM software package. The simulation results have been substantiated by measuring the horizontal displacements of the particles to be investigated under the same conditions. It is shown that the simulation results are in good agreement with the expe...
Article
Resolution characteristics of neutron spectrometers using Larmor precession of the neutron spin are limited by magnetic field homogeneities of a special type. The line integral of the modulus of the magnetic induction along a neutron trajectory of length L is a measure of the amount of precession performed by the neutron. Hence it should be precise...
Article
Full-text available
Owing to the growing emergence of the end-of-life electrical and electronic products with complex material structures and an ever-diminishing particle size of the valuable metals involved, development of eddy current separators (ECS) has been targeting selective separation of small non-ferrous metal particles smaller than 5 mm. Separability of vari...