Modeling and Studying the Cooling of Waste Tire Solid Pyrolysis Products

Every year, 1.5 billion tires are produced around the world, and each of them eventually falls into the waste stream. The growing volume of waste tires and limited possibilities for their disposal generate the need to develop methods for recycling them. A review of papers addressing the waste tire recycling problem with the use of proposed mechanical and thermochemical processing methods is presented. It is shown that researchers take interest in pyrolysis as a technology for thermochemical conversion of waste tire to produce valuable products: a solid fraction represented by coke residue (carbon black), a liquid hydrocarbon fraction (pyrolysis oil), and non-condensing gaseous fraction (pyrolysis gas). In a number of published papers, focus is placed on improving the consumer properties of each fraction. Conditions under which the coke residue quality can be improved to the level of activated carbon are, and methods for implementing this are developed. The cooling of solid pyrolysis products can be a limiting factor for the pyrolysis plant operation. Unloading of the coke residue at increased temperatures with outdoor cooling can lead to its burning out. To develop an efficient coke residue cooling heat exchanger, it is necessary to know the physical properties of this substance. A method for determining the thermal conductivity of fine coke residue based on the use of physical and mathematical modeling of the cooling process has been developed and implemented. Experiments on studying the coke residue bed cooling process in air in the temperature range from 500 °C to the ambient temperature were carried out. The time dependences of temperature at several points of the bed layer are obtained. A measuring chamber mathematical model reproducing the experimental conditions is developed. By studying the model, it is possible to determine the coke residue thermal conductivity, which approximates the calculated cooling process temperature curves to those obtained in the experiment with satisfactory accuracy. Based on the analysis of experimental data, two temperature ranges are identified, and a linear dependence of the bed thermal conductivity on the temperature is found in each of them. The coefficients of these functions are determined by minimizing the response function using the Box--Wilson method. The obtained results are used for the development of industrial thermal power engineering facilities.

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Thermal Characteristics of the Waste Tire Pyrolysis Process

Vestnik MEI ◽

10.24160/1993-6982-2021-6-37-48 ◽

2021 ◽

pp. 37-48

Author(s):

Stanislav K. Popov ◽

◽

Vyacheslav D. Vaniushkin ◽

Ernest A. Serilkov ◽

◽

...

Keyword(s):

Heat Balance ◽

Thermal Characteristics ◽

Coke Residue ◽

Engineering Practice ◽

Pyrolysis Oil ◽

Pyrolysis Process ◽

Resource Saving ◽

Pyrolysis Gas ◽

Waste Tire ◽

Balance Structure

A significant annual growth in the number of spent car tires creates a serious environmental problem and calls for the need to continue searching for efficient resource-saving methods of their recycling. There is a growing number of efforts aimed at studying waste tire thermochemical conversion processes, including their pyrolysis to obtain valuable products, including a solid fraction (coke residue), liquid hydrocarbon fraction (pyrolysis oil), and noncondensable gaseous fraction (pyrolysis gas). Commercial and pilot pyrolysis plants and reactors are reviewed. A rotating drum reactor, shaft and screw reactors are the most promising solutions for implementing a continuous process. The development of new resource-saving solutions for the pyrolysis of waste tire requires knowledge of the thermal characteristics of this process, including information on the material and heat flows in the pyrolysis reactor. The composition and thermal properties of waste tire, as well as specific outputs, composition and fuel properties of pyrolysis product material flows, including pyrolysis gas, pyrolysis oil and coke residue, are presented. Information on the pyrolysis plant or reactor heat balance structure is either absent or incomplete. Based on the data available in the literature, the heat balance of a commercial pyrolysis plant equipped with screw reactors characterized by a specific thermal destruction heat of 0.640 MJ/(kg of tires) is drawn up and studied. The numerical analysis results correlate with the data published for the commercial-grade plant. Information on the pyrolysis chamber heat balance structure is correct enough for use in engineering practice. It has been found that the specific heat consumption for the pyrolysis process is 2.269 MJ/(kg of tires). This value can be used in numerically analyzing pyrolysis plants equipped with other designs of pyrolysis reactors.

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Mathematical and Physical Modeling Cooling Process for Solid Waste Tire Pyrolysis Products

2020 V International Conference on Information Technologies in Engineering Education ( Inforino ) ◽

10.1109/inforino48376.2020.9111865 ◽

2020 ◽

Author(s):

S.K. Popov ◽

V.D. Vaniushkin ◽

A.A. Valineeva

Keyword(s):

Solid Waste ◽

Physical Modeling ◽

Cooling Process ◽

Pyrolysis Products ◽

Waste Tire ◽

Mathematical And Physical Modeling

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The Influence of the Ash Addition from Thermal Power Plant on the Mechanical, Thermal and Dielectric Characteristics of Mortars

Revista de Chimie ◽

10.37358/rc.18.8.6469 ◽

2018 ◽

Vol 69 (8) ◽

pp. 2040-2044

Author(s):

Georgeta Velciu ◽

Virgil Marinescu ◽

Adriana Moanta ◽

Ladislau Radermacher ◽

Adriana Mariana Bors

Keyword(s):

Thermal Conductivity ◽

Fly Ash ◽

Power Plant ◽

Cement Mortar ◽

Thermal Power ◽

Total Content ◽

Ash Content ◽

Dielectric Losses ◽

Dielectric Characteristics ◽

Cement Mortars

The influence of fly ash adittion (90 % fraction [ 100 mm) on the cement mortar characteristics was studied. The XRD, XRF, SEM and FTIR determinations indicated that fly ash used has a hollow microstructure of microsphere and cenosphere whose total content in SiO2, Al2O3 and Fe2O3 is 88.63 % and that of CaO and MgO of 8.55 %. The mechanical, thermal and dielectric determinations made on mortar samples with content of fly ash in the 0-40 % range have highlighted fact that the mechanical strength of cement mortars is maximal at 20 %, the increase in fly ash content leads to a decrease in relative density and thermal conductivity as well as and to increased dielectric losses tgd.

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Apparatus for routine measurements of the thermal conductivity of ice cores

Annals of Glaciology ◽

10.3189/172756499781821210 ◽

1999 ◽

Vol 29 ◽

pp. 151-154 ◽

Cited By ~ 3

Author(s):

Crescenzo Festa ◽

Aristide Rossi

Keyword(s):

Thermal Conductivity ◽

Ice Cores ◽

Maximum Temperature ◽

Transient Hot Wire ◽

Hot Wire ◽

Standard Samples ◽

Experimental Conditions ◽

Heating Source ◽

Central Segment ◽

Wire Method

AbstractAn apparatus is described for measuring the thermal conductivity of ice by the transient hot-wire method. Thermal conductivity A, is determined by tracking the thermal pulse induced in the sample by a heating source consisting of a platinum resistor. A central segment of the same platinum heating resistor acts also as a thermal sensor. A heat pulse transferred to the ice for a period of 40s gives a maximum temperature increment of about 7-14°C. In good experimental conditions, the expected reproducibility of the measurements is within ±3%. The accuracy of the method depends on whether the instrument has been calibrated by reliable standard samples, certified by absolute methods.

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Chemical Recycling of WEEE Plastics—Production of High Purity Monocyclic Aromatic Chemicals

Processes ◽

10.3390/pr9030530 ◽

2021 ◽

Vol 9 (3) ◽

pp. 530

Author(s):

Tobias Rieger ◽

Jessen C. Oey ◽

Volodymyr Palchyk ◽

Alexander Hofmann ◽

Matthias Franke ◽

...

Keyword(s):

High Purity ◽

Fractional Distillation ◽

Gas Chromatography Mass Spectrometry ◽

Thermochemical Conversion ◽

Chemical Recycling ◽

Pyrolysis Oil ◽

X Ray ◽

Benzene Toluene ◽

Halogen Content ◽

Methyl Styrene

More than 200 kg real waste electrical and electronic equipment (WEEE) shredder residues from a German dismantling plant were treated at 650 °C in a demonstration scale thermochemical conversion plant. The focus within this work was the generation, purification, and analysis of pyrolysis oil. Subsequent filtration and fractional distillation were combined to yield basic chemicals in high purity. By means of fractional distillation, pure monocyclic aromatic fractions containing benzene, toluene, ethylbenzene, and xylene (BTEX aromatics) as well as styrene and α-methyl styrene were isolated for chemical recycling. Mass balances were determined, and gas chromatography–mass spectrometry (GC-MS) as well as energy dispersive X-ray fluorescence (EDXRF) measurements provided data on the purity and halogen content of each fraction. This work shows that thermochemical conversion and the subsequent refining by fractional distillation is capable of recycling WEEE shredder residues, producing pure BTEX and other monocyclic aromatic fractions. A significant decrease of halogen content (up to 99%) was achieved with the applied methods.

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Extraordinary compatibility to mass loading and rate capability of hierarchically porous carbon nanorods electrode derived from the waste tire pyrolysis oil

Energy & Environmental Materials ◽

10.1002/eem2.12240 ◽

2021 ◽

Author(s):

Shengping Li ◽

Zipan Yang ◽

Mingzhen Wu ◽

Chenggen Xu ◽

Xilu Zhang ◽

...

Keyword(s):

Porous Carbon ◽

Rate Capability ◽

Mass Loading ◽

Pyrolysis Oil ◽

Hierarchically Porous ◽

Waste Tire

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Comparative investigation of lasing and amplification performance in cryogenic Yb:YLF systems

Applied Physics B ◽

10.1007/s00340-021-07588-8 ◽

2021 ◽

Vol 127 (3) ◽

Author(s):

Umit Demirbas ◽

Martin Kellert ◽

Jelto Thesinga ◽

Yi Hua ◽

Simon Reuter ◽

...

Keyword(s):

Continuous Wave ◽

Estimation Method ◽

Laser Cavity ◽

Comparative Investigation ◽

Limiting Factor ◽

Experimental Conditions ◽

Temperature Estimation ◽

Transverse Temperature ◽

First Time

AbstractWe present detailed experimental results with cryogenic Yb:YLF gain media in rod-geometry. We have comparatively investigated continuous-wave (cw) lasing and regenerative amplification performance under different experimental conditions. In the cw lasing experiments effect of crystal doping, cw laser cavity geometry and pump wavelength on lasing performance were explored. Regenerative amplification behavior was analyzed and the role of depolarization losses on performance was investigated. A recently developed temperature estimation method was also employed for the first time in estimating average crystal temperature under lasing conditions. It is shown that the thermal lens induced by transverse temperature gradients is the main limiting factor and strategies for future improvements are discussed. To the best of our knowledge, the achieved results in this study (375 W in cw, and 90 W in regenerative amplification) are the highest average powers ever obtained from this system via employing the broadband E//a axis.

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Bisphenol-Free Epoxy Resins Derived from Natural Resources Exhibiting High Thermal Conductivity

Proceedings ◽

10.3390/cgpm2020-07160 ◽

2020 ◽

Vol 69 (1) ◽

pp. 18

Author(s):

Matthias Sebastian Windberger ◽

Evgenia Dimitriou ◽

Frank Wiesbrock

Keyword(s):

Thermal Conductivity ◽

Natural Resources ◽

Polymer Networks ◽

Sio2 Nanoparticles ◽

Diglycidyl Ether ◽

Epoxy Compound ◽

Inorganic Materials ◽

Limiting Factor ◽

Epoxy Amine ◽

Π Stacking

Polymers commonly have low thermal conductivity in the range of 0.1–0.2 W·m−1·K−1, which is a limiting factor for their usage in the course of continuously increasing miniaturization and heat generation in electronic applications. Two strategies can be applied to increase the transport of phonons in polymers: (i) the embedment of thermally conductive inorganic materials and (ii) the involvement of aromatic units enabling anisotropy by π–π stacking. In this study, the thermal conductivity of resins based on bisphenol A diglycidyl ether BADGE and 1,2,7,8-diepoxyoctane DEO was compared. DEO can be derived from pseudo-pelletierine, which is contained in the bark of the pomegranate tree. The epoxy compounds were cured with isophorone diamine IPDA, o-dianisidine DAN, or mixtures of the both diamines. Notably, isophorone diamine is derived from isophorone of which the latter naturally occurs in cranberries. The formulations were produced without filler or with 5 wt.-% of SiO2 nanoparticles. Significantly enhanced thermal conductivity in the range of 0.4 W·m−1·K−1 occurs only in DEO-based polymer networks that were cured with DAN (and do not contain SiO2 fillers). This observation is argued to originate from π–π stacking of the aromatic units of DAN enabled by the higher flexibility of the aliphatic carbon chain of DEO compared to that of BADGE. This assumption is further supported by the facts that significantly improved thermal conductivity occurs only above the glass-transition temperature and that nanoparticles appear to disrupt the π–π stacking of the aromatic groups. In summary, it can be argued that the bisphenol-free epoxy/amine resin with an epoxy compound derivable from natural resources shows favorably higher thermal conductivity in comparison to the petrol-based epoxy/amine resins.

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