Article

Review of Waste Tire Reuse& Recycling in China: current situation, problems and countermeasures

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Abstract

This article first expounds the current situation on waste tire generation and recycling in China. Then it analyses the existing problems and causes in the industry of waste tire recycling. Finally, it proposes countermeasures and suggestion on promoting a healthy waste tire industry. These strategies include accelerating the speed of drawing up regulations on waste tire reuse and recycling management, completing encourage policies and mechanism of waste tire resource recycling industry, developing adequately the influence of China Rubber Industry Association (CRIA) and China Tire Retreading And Utilization Association (CTRA), and etc.. China has an abundant resource of waste tires and recycling potential. And it will be of great significance to mitigating the scarcity of rubber resource, improving ecological environment, developing circular economy and building resource-efficient society in China if we can reuse and recycle waste tires properly and form a healthy waste tire industry.

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... The latest statistical data reported that the total amount of used tyres generated in the world is constantly increasing, while the largest their quantities are produced in China (approx. 5.7 million tonnes, data cover only the tyres recovered by the recycling in 2010), U.S. (3.824 million tonnes in 2013) in the European Union (3.418 million tonnes in 2012) and Japan (1.052 million tonnes in 2014) (JATMA, 2015;Hu et al., 2014;ETRMA, 2013;CRIA, 2010;RMA, 2009;Li et al., 2010;Wang et al., 2009). However it should be noted that in these countries, the recovery and recycling of used tyres became a separate branch of the industry, which produces energy or many kinds of useful materials and brings huge profits. ...
... The statistics which describe the methods of waste tyres management in China are incomplete and on their basis it is difficult to characterize the market of recovery of used tyres in this country. However, based on some papers (Hu et al., 2014;Li et al., 2010;Wang et al., 2009) and data published by China Rubber Industry Association (CRIA, 2010) it can be concluded that the major direction of used tyres utilization is recycling realized by dynamic devulcanization (approx. 54% of total recycling), grinding tyres and production of rubber granulates (approx. ...
... From the material engineering point of view, the main merits of polymer composites are their small mass, great mechanical strength and resistance to fatigue elasticity and resistance to chemical and environmental agents (Strong, 2007). In recent years it has appeared a qualitatively novel group of sustainable composites obtained from polymer wastes (especially tyre rubber), which seems to be more attractive in relation to environmental Table 1 The legislation regulation and models in management of used tyres recovery in EU27, U.S., Japan and China (JATMA, 2015;Hu et al., 2014;ETRMA, 2011;ETRMA, 2013;CRIA, 2010;RMA, 2009;Li et al., 2010;Wang et al., 2009;WBCSD, 2008 Each state in the U.S. has its own law regulations concerning reuse/recovery and landfilling of used tyres: (38 states ban on the stockpiling whole tyres in landfills; 35 states allow the stockpiling grinded tyres in landfills; 11 states ban on the stockpiling all tyres in landfills; 21 states allow the stockpiling grinded tyres into monofills (landfill for the disposal of one kind of material); 8 states don't have restrictions on stockpile used tyres in landfills.); 36 states require permits from used tyres haulers; 37 states have state fees for used tyres; 14 states require financial assurances from used tyres haulers; 32 states require financial assurance from recovery companies; the U.S.; Environmental Protection Agency (EPA) reporting that 48 states currently have laws and regulations for management scrap tyres. ...
Article
Rubber products, especially those used in the automotive industry, are responsible for a significant amount of waste, mainly in the form of worn tyres. One way to recycle tyres is to use them as an asphalt binder modifier. The properties of rubber-asphalt binders vary greatly depending on the morphology of the ground tyre rubber (GTR) grains and the type of tyre to be recycled (car/truck). The paper presents the results of research in the field of rubber-asphalt binders modified with two types of GTR (which differ in grain morphology) used in various amount and processed at different mixing devices. One GTR is obtained with the use of a standard knives granulator (standard granulation process – SGP), and the other by a special flat die pelleting press (flat-die granulation process – FDGP). It has been proved that GTR grinding method affects its specific surface area, thus the properties of rubber-asphalt binders.
... The latest statistical data reported that the total amount of used tyres generated in the world is constantly increasing, while the largest their quantities are produced in China (approx. 5.7 million tonnes, data cover only the tyres recovered by the recycling in 2010), U.S. (3.824 million tonnes in 2013) in the European Union (3.418 million tonnes in 2012) and Japan (1.052 million tonnes in 2014) (JATMA, 2015;Hu et al., 2014;ETRMA, 2013;CRIA, 2010;RMA, 2009;Li et al., 2010;Wang et al., 2009). However it should be noted that in these countries, the recovery and recycling of used tyres became a separate branch of the industry, which produces energy or many kinds of useful materials and brings huge profits. ...
... The statistics which describe the methods of waste tyres management in China are incomplete and on their basis it is difficult to characterize the market of recovery of used tyres in this country. However, based on some papers (Hu et al., 2014;Li et al., 2010;Wang et al., 2009) and data published by China Rubber Industry Association (CRIA, 2010) it can be concluded that the major direction of used tyres utilization is recycling realized by dynamic devulcanization (approx. 54% of total recycling), grinding tyres and production of rubber granulates (approx. ...
... From the material engineering point of view, the main merits of polymer composites are their small mass, great mechanical strength and resistance to fatigue elasticity and resistance to chemical and environmental agents (Strong, 2007). In recent years it has appeared a qualitatively novel group of sustainable composites obtained from polymer wastes (especially tyre rubber), which seems to be more attractive in relation to environmental Table 1 The legislation regulation and models in management of used tyres recovery in EU27, U.S., Japan and China (JATMA, 2015;Hu et al., 2014;ETRMA, 2011;ETRMA, 2013;CRIA, 2010;RMA, 2009;Li et al., 2010;Wang et al., 2009;WBCSD, 2008 Each state in the U.S. has its own law regulations concerning reuse/recovery and landfilling of used tyres: (38 states ban on the stockpiling whole tyres in landfills; 35 states allow the stockpiling grinded tyres in landfills; 11 states ban on the stockpiling all tyres in landfills; 21 states allow the stockpiling grinded tyres into monofills (landfill for the disposal of one kind of material); 8 states don't have restrictions on stockpile used tyres in landfills.); 36 states require permits from used tyres haulers; 37 states have state fees for used tyres; 14 states require financial assurances from used tyres haulers; 32 states require financial assurance from recovery companies; the U.S.; Environmental Protection Agency (EPA) reporting that 48 states currently have laws and regulations for management scrap tyres. ...
Article
The paper is transdisciplinary. The complex overview on changes in policy and approach to waste tyres that leads to both solving environmental problem of post-consumer tyres and creating environmentally friendlier novel materials are presented. It is shown that in the world, the amount of polymer wastes increases every year. Most of them are in the form of post-consumer tyres. Recycling and recovery of such tyres is a serious environmental problem due to their very complex structure and composition. Moreover, storage of the whole post-consumer tyres takes a lot of space in landfills and pollute the environment. However, recently it has been reported a great progress in sustainable management of waste tyres. An important role in the progress of tyre recovery has played the establishment of the restrictive regulations, which prohibits stockpiling of tyres in landfills. This legislative steps have contributed to significant impact on the progress in the development of car tyres recovery. The most important is introducing of monitoring for improper stockpiling, producer responsibility for wastes tyres and the new tax system. With the help of mentioned changes and introducing environmentally friendlier technologies it appeared that the utilization of tyres can be cost effective. The applied technology can transform post-consumer tyres into a source of energy or valuable raw materials, from which can be obtained a wide range of sustainable polymeric composite materials characterized by quite good mechanical and functional properties. This new approach to post consumer tyres is undertaken in U.S., China, Japan and EU. From the overview it is clear that the grinded used tyres should not be treated any more as a pollutant but rather as a source of sustainable materials. Those materials belong to modern polymer-rubber composites obtained mainly from elastomers (natural and synthetic rubbers) or thermoplastics (PE, PP, PVC). The very important factor in making good composites is get the knowledge about the influence of amount, size and morphology of rubber granulate grains on interactions that occur in composites between the polymer matrix and tyre rubber grains and thus the properties. That last item was discussed in the final part of the overview.
... Wellmanaged tires may be retreaded at least twice before being classified as end of life tire. Both reusable and retreaded tire markets suffer from competitive new tire price as well as consumer concerns over safety and reliability [5,29]. ...
... Retreading is the most economically viable method of waste tire utilization as it requires only 30% of energy and 25% of raw materials used to manufacture a new tire [5]. However, at current market, retreaded tires are scarce [29]. Efforts should be taken to boost the market for retreaded tire. ...
Article
This review addresses the progress in waste tire recycling with a particular attention to incorporation of waste tire rubber (WTR) into polymeric matrices. Methods of waste tire downsizing, importance of WTR characterization and current practice of WTR modification has been emphasized. Detailed discussion on influence of WTR size, loading, modification, compatibilization and crosslinking on the rheological, mechanical and thermal properties of rubber, thermoplastic and thermoplastic elastomer blends utilizing WTR has been reported. By far, thermoplastic elastomer blends; though still in its infancy; has shown the most promising properties balance which is capable of commercialization. Rubber/WTR blends also show ease of processing and acceptable properties. Thermoplastic/WTR blends suffers in term of toughness and elongation at break. However, the waste thermoplastic/WTR is a viable solution to address polymeric waste problem. Review also highlights the lack of studies concentrating on dynamic mechanical, aging, thermal and swelling properties of WTR polymeric blends.
... As a result, open discarding of scrap tire not only occupies a large space, provides an eyesore and could cause environmental hazards and potential health, but also describes depletion of valuable energy resource [14]. [15][16][17][18][19][20][21]. ...
... Due to high demand for the new materials in the European Union countries, the recovery of used tires is stood primarily on the recycling process beside the energy recovery of used tires [18]. According to the data published by China Rubber Industry Association [22] and some papers, it can be resolved that the most important trend of used tires recovery is recycling realized by dynamic devulcanization (~54%), pyrolysis and tire oil extraction (~40%) as well as grinding tires and production of rubber granulates (~ 7%) [16,20,21]. It should be stress that China is the main producer and consumer of recovered rubber in the world. ...
... Wellmanaged tires may be retreaded at least twice before being classified as end of life tire. Both reusable and retreaded tire markets suffer from competitive new tire price as well as consumer concerns over safety and reliability [5,29]. ...
... Retreading is the most economically viable method of waste tire utilization as it requires only 30% of energy and 25% of raw materials used to manufacture a new tire [5]. However, at current market, retreaded tires are scarce [29]. Efforts should be taken to boost the market for retreaded tire. ...
... Conversion of CB p to activated carbon can contribute to increase tire recyclability if the activated carbon quality is sufficient (Trubetskaya et al., 2019). Up until now, many review papers have been published on tire and rubber recycling covering all the recycling processes from powdering to devulcanization and pyrolysis (Akca et al., 2018;Asaro et al., 2018;Fazli and Rodrigue, 2020;Markl and Lackner, 2020;Ramarad et al., 2015;Saputra et al., 2021;Shu and Huang, 2014;Stevenson et al., 2008;Wang et al., 2010). In these papers, each has challenged a part of tire recycling, but no clear road map has been drawn for the whole tire recycling industry. ...
Article
Full-text available
End-of-life tires are discarded on a daily basis but even at present limited action has been taken towards boosting their recyclability as most of the tires are either incinerated or landfilled/stockpiled. The complexity of tires has also been drastically increased, with little attention to designing them specifically for recycling. The retreading process is currently under intense development, and end-of-life tires have the ability to be retread up to several times. Furthermore, powdering (pulverization and grinding) the tires and separating steel and textile from this stream is a promising route that has found expanding applications. The particle size and surface area of the produced powder, purity, rubber degradation, and the cost of equipment and production are the determining factors. Assessing all these factors shows that sc-CO2 pulverization is the most promising method overall in this respect. In terms of process-ability, devulcanization has received a lot of attention from the tire recycling industry, and numerous physical, chemical, and microbial processes and combinations are being developed to be industrialized in the near future. Nevertheless none of these processes is currently at a high enough technological readiness level to be operated at large scale. Literature data shows that extrusion in combination with an ultrasonic horn or sc-CO2 using diphenyl disulfide has the most potential. In the dissolution extraction process, in addition to breaking sulfur bonds, solvent extraction devulcanizes and separates rubber from other tire components at low temperatures. The purity of the extracted products e.g., rubber, carbon black (CB) and minerals in this way is much higher than that of other recycling methods. Since applications of mentioned recycled products (powder and devulcanized tire) are limited, tire pyrolysis has become extremely important. Process parameters and reactor design play a significant role in degradation mechanisms and pyrolysis products e.g., light olefins and dienes, naphthenes, mono-aromatics, tar, polar aromatics and coke. Catalytic pyrolysis with promoted zeolites leads to larger yields of valuable products at the expense of the formation of tar and so-called polar aromatics, i.e. N/S/O containing aromatics. In addition, upgrading processes, e.g., hydro-treating can reduce polar aromatics in the pyrolysis products by up to 90%. Furthermore, the demineralization of pyrolytic carbon black and activated carbon production are promising processes that result in increased tire recovery rates.
... stockpiled throughout the world. [3] Out of which, more than 283 million scrap tyres were generated in China each year, and 270 million in the USA. [4] Since the polymeric rubber could not decompose naturally, recycling of these 2 K. Yu et al. scrap tyres become necessary. ...
Article
The polycyclic aromatic hydrocarbons (PAHs) in crumb tire rubber were firstly degraded under UV irradiation in the presence of rutile TiO2 and hydrogen peroxide. The effects of light intensity, catalyst amount, oxidant amount, initial pH value, co-solvent content, and reaction time on degradation efficiency of typical PAHs in crumb tire rubber were studied. The results indicated that UV irradiation, rutile TiO2, and hydrogen peroxide were beneficial to the degradation of PAHs and co-solvent could accelerate the desorption of PAHs from crumb tire rubber. Up to 90% degradation efficiency of total 16 PAHs could be obtained in the presence of rutile TiO2 (1 wt%) and hydrogen peroxide (1.0 mL) under 1800 μW cm(-2) UV irradiation for 48 h. The high molecular weight PAHs (such as benz(a)pyrene) were more difficult to be degraded than low molecular weight PAHs (such as phenanthrene, chrysene). Moreover, through the characterization of reaction solution and degradation products via GC-MS, it was proved that the PAHs in crumb tire rubber were successfully degraded. Supplementary material.
... In recent years, China has become the biggest rubber consumer and rubber import country. It generates as many as 100 million waste tires while the recycling rate is only about 10 %, which is far lower than those of developed countries (Wang et al. 2009). Most of Tire are mixed in MSW and incinerated. ...
Article
Full-text available
To determine the association between daily air pollution and the hospital admissions for respiratory diseases in children aged from 0 to 17 years in Jinan, China. Generalized linear models were used to explore the acute effects of ambient fine particulate matter (PM2.5) on the children’s hospital admissions for respiratory diseases. We evaluated the lag associations (including lag 0 to lag 3, lag 01, and lag 03) between daily PM2.5 and the number of children’s hospital admissions for respiratory diseases, and stratified by gender, age group (baby group: age 0–1 years; child group: age 1–5 years; student group: age 6–17 years), and cause-specific disease (including upper infection, pneumonia, and acute bronchitis) during 2011–2015. PM2.5 had significant positive impacts on the number of children’s hospital admissions for respiratory disease. The results showed that per 10 μg/m³ increase of PM2.5 at lag 1 was associated with an increase in total and male hospital admissions of 0.23% (95% CI, 0.02%–0.45%) and 0.32% (95% CI, 0.04%–0.06%). The corresponding risk of the student group (age 6–17 years) hospital admissions was increased 0.90% (95% CI, 0.39%–1.42%) at lag 1 day. The corresponding risk of the upper infection was increased 0.96% (95% CI, 0.37–1.55%) at lag 1 day. Males and student groups (age 6–17 years) were more vulnerable to PM2.5 exposure. Upper infection admission was identified as the sensitive disease for children. It is a better way to reduce children’s outdoor activities to avoid health effects when the air pollution increases.
... Not timely woodland, forest ownership change of registration, there are many forest without a certificate or vice versa. Thus in the circulation process mountainous ownership mistaken identity, boundary confusion, "have repeatedly occurred in a forest to buy more" phenomenon, caused a lot of forest rights disputes [6]. ...
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It is a core content of collectively-owned forest rights reform to make clear property right, which is closely related to stability and perfect of basic rural management institution, increasing of peasant income, biological construction and development of modern forestry. Based on analysis of defects of property right institution of collectively-owned forest rights in China, the paper suggests that the nature of collectively-owned institution should been laid aside, the legal status of rural collective economic organization should been clear, the whole collectively-owned forest rights should been built and the registration of collectively-owned forest rights should been perfected.
... Landfill retreaded tires are scarce (Wang et al., 2009a). Efforts should be taken to boost the market for retreaded tire. ...
... The developing of alternative fuel has been investigated in the past decade due to the fast depletion of fossil fuels [1]. The aim of these technologies is to recover energy from waste materials, including materials that are not biodegradable, such as biomass, municipal solid wastes, agricultural wastes and as high energy density materials such as rubber and plastics [2]. ...
Article
Full-text available
... Se han investigado diversas formas de recuperar energía a partir de materiales de desecho, incluyendo materiales no biodegradables, residuos sólidos municipales, desechos industriales, agrícolas, así como también materiales de alta densidad energética, tales como el caucho y plásticos (Wang et al., 2010), presentando la pirólisis, una ventaja importante desde el punto de vista del reciclaje, ya que permite tratar residuos que de otra forma serían difícilmente reciclables, y obtener productos que se pueden volver a utilizar (Martínez et al., 2013). ...
Article
Full-text available
Characteristics of the liquid product obtained from waste tire pyrolysis were assessed after 40 minutes of isothermal pyrolysis. The process was carried out in conditions ranging 450 to 550 °C, 10 to 20 °C/min and 1 to 3 mm particle size, according to a 23 factorial design with center point runs. The regression model indicates that, within a confidence interval of 95%, the heating rate and its interactions have no statistically significant effect in the liquid product yield, within the search space of the experiment. The liquid product's density, viscosity, flash point, cetane index, and heating value resemble those of diesel fuel. Nonetheless it needs previous refinement to reduce its sulfur content, a hundred times larger than the specified in Paraguayan standards, prior to its use in modern diesel engines. Additionally, the solid product's characteristics resemble those of anthracite, with a higher heating value of 29.3 MJ/kg.
... The removal of the huge quantities of tyre waste produced around the world is currently an economic and environmental issue. It is predicted that waste tyres generated annually represent 4.5 million tonnes in Europe (European Tyre and Rubber Manufacturers Association ETRMA 2011), 5.2 million tonnes in the USA (United States Mine Rescue Association USRMA 2011), 1.2 million tonnes in Japan (Japan Automobile Tyre Manufacturers Association JATMA 2011), 5.2 million tonnes in China (Wang 2009), and 0.9 million tonnes in India (Indian Tyre Industry ITI 2011), representing 88 % of the whole tyre production worldwide (JATMA 2011). ...
Article
Full-text available
A review of the energy recovery from waste tyres is presented and focuses on the three thermochemical processes used to valorise waste tyres: pyrolysis, gasification, and combustion/incineration. After recalling the chemical composition of tyres, the thermogravimetric behaviours of tyres or their components under different atmospheres are described. Different kinetic studies on the thermochemical processes are treated. Then, the three processes were investigated, with a particular attention given to the gasification, due to the information unavailability on this process. Pyrolysis is a thermochemical conversion to produce a hydrocarbon rich gas mixture, condensable liquids or tars, and a carbon-rich solid residue. Gasification is a form of pyrolysis, carried out at higher temperatures and under given atmosphere (air, steam, oxygen, carbon dioxide, etc.) in order to yield mainly low molecular weight gaseous products. Combustion is a process that needs a fuel and an oxidizer with an ignition system to produce heat and/or steam. The effects of various process parameters such as temperature, heating rate, residence time, catalyst addition, etc. on the energy efficiency and the products yields and characteristics are mainly reviewed. These thermochemical processes are considered to be the more attractive and practicable methods for recovering energy and material from waste tyres. For the future, they are the main promising issue to treat and valorise used tyres. However, efforts should be done in developing more efficient technical systems.
... In Thailand, nearly 400,000-600,000 tonnes of WTs are generated per year (Connor et al., 2013). In China, more than 112 million WTs are generated every year (Wang et al., 2009), whereas in South Africa more than 11 million units of end-of-life tires (ELTs) are generated annually (Mahlangu, 2009). The total number of WTs disposed of in Australia was around 408,000 tonnes in the 2013-2014 period (Mountjoy et al., 2015). ...
Article
Waste tyres (WTs) are becoming a significant environmental, economical and technological challenge due to their high contents of combustible composition and potential for valuable materials and energy resources. Fewer studies in developing and even developed countries have been carried out to assess the challenges regarding waste tyres management, and suggested the best alternative solutions for managing this waste stream. While developed countries made progress in waste tyres management needs by implementing more efficient innovative recovery and recycling methods, and restrictive regulations regarding the management of used tyres, in many developing countries the management of waste tyres has not received adequate interest, and the processing, treatment and disposal of waste tyre is still nascent. In recent years, worldwide, several methods for managing used tyres, including other principal alternatives for managing end-of-life tyres defined in the 4Rs, reduction, re-use, recovery and recycling have been adopted and applied to minimize serious threats to both the natural environment environment and human. The paper attempted to establish stakeholders’ action that has the responsibility in waste tyre management in Botswana. This study also analyzed important aspects on waste tyres management in Botswana. A synthesis of approaches was employed in the present investigation to determine the factors influencing effective performance of waste tyres management practice in Botswana. Data for the present study was obtained using relevant published literature, scientific journals, other third sector sources, academic sources, and research derived from governments and other agencies and field observations. Group discussions with the participants and semi-structured interviews with professionals were carried out. The outcomes of this investigation are a wide-range outline concerning the participants that are important in waste tyres management, and a set of aspects affecting the management of waste tyres. The information provided by this study is very critical for reviewing and updating the methods and tools to update waste tyres data and trends to improve waste tyres management efficiency, suggesting innovative methods of recovering and recycling this waste stream in Botswana.
... In Asia, industrial countries in East Asia like China and Korea are the countries that most consume rubber for tire production. For example, in China the number of waste tires produced exceeded 239 million tires in 2004 [12]. With the increase in production of waste tires in China, the government tends to make use of such beneficial raw material, where only 10% is being recycled. ...
Article
Full-text available
Fast development of automotive industry and rising vehicle use is giving rise to large amount of waste tire production and generation worldwide. Tire waste management continues to be a growing crisis over most developing countries due to insufficient funding, poor infrastructure and absence of effective legislations and policy framework. Waste tire management is challenging in Lebanon due to wide use of vehicles with minimal amount of tire recycling. Being a relatively new stream of waste and with less priority from government, the waste tire management in Lebanon is at infancy stage, and needs appropriate and aggressive policies, plans and strategies. This paper investigates Lebanon’s specific issues and options for a viable long-term waste tire management strategy through studying the feasibility of three different options to reduce tire waste. The three different alternatives studied are: Tire Retreading, Tire Shredding, and Tire Pyrolysis. Current practices, potential technologies, and successful systems from foreign nations were evaluated to draw conclusions and recommendations regarding which technology is most applicable to Lebanon and which aspects of a waste tire management system needed to be newly implemented or continued to be used and improved. Taking into consideration the survey results, retreading seems an interesting way to treat waste tires in the study area.. Keywords Tire Pyrolysis, Tire Retreading, Tire Shredding, Waste Tires.
... In Latvia, the number of recycled EOL tyres is still comparatively low, especially upcycling component manufacturing products with higher value added. Wang with a co-author endorse the importance of the government in encouraging EOL tyre recycling by setting up policy planning and legislative framework, other social and cooperation mechanisms [37]. In this context the Green Public Procurement (GPP) is an essential government incentive that could encourage the transition of tyre-recycling and related business sectors towards the circularity, especially in the construction, military or transport sectors (see product examples in Fig.2). ...
... Millions of tons of waste tires are produced worldwide: about 2.5 million tons is generated in North America, Japan generates one million tons and the European Community generates more than 2.5 million tons [3]. In Palestine, in 2012, it was estimated that more than 380 thousand scrap tires were generated from different sources [4]. ...
Article
Full-text available
The first industrial-scale pyrolysis plant for solid tire wastes has been installed in Jenin, northern of the West Bank in Palestine, to dispose of the enormous solid tire wastes in the north of West Bank. The disposable process is an environmentally friendly process and it converts tires into useful products, which could reduce the fuel crisis in Palestine. The gravimetric analysis of tire waste pyrolysis products from the pyrolysis plant working at the optimum conditions is: tire pyrolysis oil (TPO): 45%, pyrolysis carbon black (PCB): 35%, pyrolysis gas (Pyro-Gas): 10% and steel wire: 10%. These results are depending on the tire type and size. It has been found that the produced pyrolysis oil has a High Heating Value (HHV), with a range of 42 − 43 ( MJ / kg ) , which could make it useful as a replacement for conventional liquid fuels. The main disadvantage of using the TPO as fuel is its strong acrid smell and its low flash point, as compared with the other conventional liquid fuels. The produced pyrolysis carbon black also has a High Heating Value (HHV) of about 29 (MJ/kg), which could also encourage its usage as a solid fuel. Carbon black could also be used as activated carbon, printers’ ink, etc. The pyrolysis gas (Pyro-Gas) obtained from waste tires mainly consist of light hydrocarbons. The concentration of H2 has a range of 30% to 40% in volume and it has a high calorific value (approximately 31 MJ / m 3 ), which can meet the process requirement of energy. On the other hand, it is necessary to clean gas before the burning process to remove H2S from Pyro-Gas, and hence, reduce the acid rain problem. However, for the current plant, some recommendations should be followed for more comfortable operation and safer environment work conditions.
... Annually, ∼15 million tons of waste tires are produced worldwide whereas North America and European Community generates more than ∼2.5 million tons of waste tires, Japan generates ∼1 million tons and India also produces ∼1 million waste tires [15]. Additionally, million tonnes of waste tires are imported to developing countries from the developed nations. ...
Chapter
Automobiles production is increasing at a faster rate due to rapid globalization and industrialization. However, after its end of life of automobiles huge amount of waste are getting generated. One of the wastes is used tyre. Worldwide, 1 billion tonnes of used tyres are generated as a waste every year. However, the processing of the waste tyres is extremely challenging due to their complex structure and varied composition; therefore, it has been directly thrown or burned. Thus, inadequate management of used (waste) tyres causes an adverse impacts to the environment and social life. In this regard, gasification and pyrolysis techniques are being used to convert the waste tyres into fuel and energy. This chapter describes the environmental impacts associated with waste tyres if it is not processed properly and energetic valorisation of waste tires into fuel and energy.
... Millions of scrap tires are stored in the ecosystem annually, causing environmental issues [16]. Some countries have recently invested in recycling and reusing waste tires, but still, in other countries, it is only a small percentage of waste tires that are recycled or reused, and the rest are destined for landfills, stockpiles, or illegal disposals [17][18][19][20]. ...
Article
Full-text available
Blasting is an unavoidable activity in geotechnical engineering, road and tunnel construction, and mining and quarrying. However, this activity can expose the environment to various hazards that are challenging to control and, at the same time, critical for the safety of site workers, equipment, and surrounding structures. This research aims to evaluate the ability of sand–tire shred mixtures to reduce peak blast pressure, which is the leading cause of damage to underground structures under surface explosion. ABAQUS software is used to model the material behavior under explosion and is validated using the results of previous studies and an empirical equation. Different scenarios are created by using mixture layers with different thicknesses (2, 4, and 6 m) and tire shred contents (10%, 20%, and 30%) that are subjected to various surface explosion charges (100, 500, 1000, and 5000 kg). The thickness of the mixture layer is found to be directly related to the dissipation of explosion energy. However, the percentage of the rubber content in the mixture is only significant in reducing peak blast pressure when a thick enough mixture layer is used. The results confirm the adequate performance of the correctly chosen sand–tire shred mixtures in reducing peak blast pressure and protecting the underground structure from surface explosion hazards.
... In China region, the case is not different especially due to the population and extremely large number of automobiles. China waste tyre generation was expected to be 5.2 million tonnes in 2010 and thereby becoming one of the world largest producers of waste tyres [2,6]. ...
Article
During pyrolysis of waste tyre, the operating parameters such as tyre composition, the process temperature, the heating rate and the particle size affect the result of the pyrolysis. Some of these parameters have been closely considered but the particle size of the waste tyre is often ignored. In this paper, the size of the waste tyre particle is considered as a major factor in determining the magnitude of the overall energy used as well as the completion time of the pyrolysis reaction. Simulations were conducted to compare the effects of the particle size on the completion time and the overall energy usage under different heating rates and operational strategies. Shredding energy needed to reduce waste tyre particles was also included into the calculation of the overall energy consumption. Optimisation of the particle size was conducted under a number of specified maximum completion times and heating rates.
Chapter
Waste management is an important indicator for creating sustainable and livable cities, but it remains a challenge for many countries around the world. Millions of rubber tire waste pollute the environment due to improper disposal methods, creating a global environmental crisis. The number of rubber tire waste piles continues to grow, posing greater environmental, safety, and aesthetic issues due to a lack of clear disposal options. This chapter gives a general overview of rubber tire waste recycling and disposal worldwide. A brief history of natural and synthetic rubber and global rubber production and consumption was first discussed. Next, various rubber tire recycling and disposal technologies were elaborated. This is followed by discussing the issues involved in recycling and disposal.
Chapter
Solar Fuels and chemicals from CO2 can be produced through two main reactions: one is CO2 photoreduction, using different catalysts and different reducing agents; the other is CO2 fixation, which is usually performed through natural photosynthesis. The research nowadays is directed on the production of fuels and chemicals with one or two atoms of carbon, for example CH4, CO, HCOOH, HCHO, CH3OH, C2H5OH, etc. The chapter aims at comparing natural photosynthesis processes and reactions with artificial photosynthesis. After taking into consideration the natural photosynthetic process, the chapter focuses on heterogeneous and homogeneous photocatalysis. Heterogeneous catalysis can be performed with semiconductors and powder catalysts. Special attention is given to TiO2 as a promising photocatalyst. Homogeneous photocatalysts are usually represented by molecular catalysts, which are dissolved in water or another solvent. Usually, homogeneous photocatalysis is performed in complex systems which are composed by: a light harvesting unit (LHU) (i.e. the photosensitizer); one catalytic site for the oxidation process, where the electrons are supplied by a sacrificial donor; one reduction site, where the electrons are transmitted to CO2. Finally, even more complex systems are represented by those based on photoelectrocatalysis. These have the main advantage to separate the oxidation and reduction reactions at the two different electrodes of the system. In principle photoelectrochemical cells can be a way to mimic artificially the working principle of natural photosynthesis.
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Total generation amount of scrap tires in China and the U.S. reach 500 million and total weights are about 10 million tons. Management on scrap tires is the common challenges for both countries. In this paper, generation situations, material flows and management policies of the two countries were analyzed and compared. Comparison results show higher possession of private vehicles and higher retreading ratio for commercial trucks in the U.S. results in relatively higher generation amounts (0.3billion units) and relatively lighter weights (4.4 million tons). Management policies on scrap tires in the U.S. are more comprehensive and stricter than those in China. The successful implementation of economic instruments in the U.S provides practical experiences for China to improve material flows and avoid illegally oil refining. In the U.S. co-disposed as an alternative fuel is the main outlet for scrap tires, while in China they are mainly recycled to produce reclaimed rubber.
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This study investigated the adsorption properties of demineralised activated carbon adsorbents produced from waste tyre char. The produced carbon was tested for its dye adsorption capacities in the textile industry effluent treatment. Two acid dyes with different molecular sizes were used, namely Acid Blue 25 (AB25) and Acid Yellow 117 (AY117) to simulate the textile effluent. In a single component system, it was found that the larger size dye, AY117, showed little adsorption and for both dyes the maximum capacity is higher than the commercial activated carbon F400 for both dyes. Furthermore, the results of the single component system were fitted to equilibrium isotherm models using Langmuir, Freundlich, Redlich–Peterson and Langmuir–Freundlich or Sips for the single component system. The adsorption of AB25 followed the Langmuir isotherm, while the adsorption of AY117 can be better described with Langmuir–Freundlich model. A binary AB25–AY117 mixture was used to test the possibility of the molecular sieve effect. For the binary component system, it is found that none of the predictive models work well, hence the system is non-ideal. Overall, the correlative extended Freundlich isotherm models were the best to fit the experimental data.
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The pyrolysis-catalytic steam gasification of waste tyres has been investigated using a two-stage fixed bed reactor. The catalyst used was Ni/Al2O3. The influence of the process parameters, catalyst:waste tyre ratio, gasification temperature and water injection rate on hydrogen production were investigated. The results indicated that the potential H2 production (conversion of the hydrogen in the tyre to hydrogen gas) was 7.19 wt.% when the catalyst:waste tyres ratio was 0.5 (g/g), which increased to 20.0 wt.% at the catalyst:waste tyres ratio of 2.0 (g/g). Increasing the gasification temperature from 600 to 900 °C was shown to increase gas yield from 14.3 wt.% to 56.8 wt.% and the potential H2 production increased from 3.2 to 13.1 wt.%. The steam flow rate, in terms of the amount of water injected, had a small but significant influence on the potential H2 production. The characteristics of the carbon deposited on the reacted catalysts were examined by temperature-programmed oxidation (TPO) and scanning electron microscopy (SEM) and were shown to consist of be monoatomic carbon and filamentous carbon. The amount of carbon deposited on the catalyst was reduced with an increase in the amount of catalyst used and the water content. However, the highest amount of coke deposited on the catalyst was 20.8 wt.% for the gasification temperature of 700 °C.
To Establish Scientific Point Of View On Development To Promote The Business Develop Healthily
  • Li Ru-Lin
LI Ru-lin. (June 2005).To Establish Scientific Point Of View On Development To Promote The Business Develop Healthily. Proc. of The National Waste Tire Rubber Powder Applied Technology, Tianjin, China.
Waste Tires: Black Golden Mine
  • Li Xiao-Ming
LI Xiao-ming. (2003). Waste Tires: Black Golden Mine. Investment In China, (12), 46-48.
Current Situation And Development In Scrap Rubber Utilization Industry Of China
  • Lu Yong-Qi
LU Yong-qi. Current Situation And Development In Scrap Rubber Utilization Industry Of China. Rubber In China, 20 (12), 4-7.
Develop Up And Down For A New Prospect Of Tire Recycling
  • Cheng Yuan
CHENG Yuan. (June 2005). Develop Up And Down For A New Prospect Of Tire Recycling. Proc. of The National Waste Tire Rubber Powder Applied Technology, Tianjin, China.
Make Effort To Improve Scrap Tire Rubber Powder Applied Technology And Promote The Development Of Waste Tire Enterprises
  • Jiang Zhi-Yun
JIANG Zhi-yun. (June 2005). Make Effort To Improve Scrap Tire Rubber Powder Applied Technology And Promote The Development Of Waste Tire Enterprises. Proc. of The National Waste Tire Rubber Powder Applied Technology, Tianjin, China.