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This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking on heat transfer.

A brief review of current research on supercritical aviation kerosene is presented in views of the surrogate model of hydrocarbon fuels, chemical cracking mechanism of hydrocarbon fuels, thermo-physical properties of hydrocarbon fuels, turbulence models, flow characteristics and thermal performances, which indicates that more efforts need to be directed into these topics. Therefore, supercritical thermal transport of n-decane is then computationally investigated in the condition of thermal pyrolysis, while the ASPEN HYSYS gives the properties of n-decane and pyrolysis products. In addition, the one-step chemical cracking mechanism and SST k-ω turbulence model are applied with relatively high precision.

The existing surrogate models of aviation kerosene are limited to a specific scope of application and their thermo-physical properties deviate from the experimental data. The turbulence models used to implement numerical simulation should be studied to further improve the prediction accuracy. The thermal-induced acceleration is driven by the drastic density change, which is caused by the production of small molecules. The wall temperature of the combustion chamber can be effectively reduced by this behavior, i.e. the phenomenon of heat transfer deterioration can be attenuated or suppressed by thermal pyrolysis.

The issues in numerical studies of supercritical aviation kerosene are clearly revealed, and the conjugation mechanism between thermal pyrolysis and convective heat transfer is initially presented.

In this paper the aim is that Aramid/alginate blended nonwoven fabrics were prepared, and the flame retardancy of the blended nonwoven fabrics was studied by thermogravimetric analysis, vertical flame test, limiting oxygen index (LOI) and cone calorimeter test.

The advantages of different fibers can be combined by blending, and the defects may be remedied. The study investigates whether incorporating alginate fibers into aramid fibers can enhance the flame retardancy and reduce the smoke production of prepared aramid/alginate blended nonwoven fabrics.

Thermogravimetric analysis indicated that alginate fibers could effectively inhibit the combustion performance of aramid fibers at a higher temperature zone, leaving more residual chars for heat isolation. And vertical flame test, LOI and cone calorimeter test testified that the incorporation of alginate fibers improved the flame retardancy and fire behaviors. When the ratio of alginate fibers for aramid/alginate blended nonwoven fabrics reached 80%, the incorporation of alginate fibers could notably decreased peak-heat release rate (54%), total heat release (THR) (29%), peak-smoke production rate (93%) and total smoke production (86%). What is more, the lower smoke production rate and lower THR of the blends vastly reduced the risk of secondary injury in fires.

This study proposes to inhibit the flue gas release of aramid fiber and enhance the flame retardant by mixing with alginate fiber, and proposes that alginate fiber can be used as a biological smoke inhibitor, as well as a flame retardant for aramid fiber.

This paper aims to present the production of waste plastic oil from landfill waste plastics, the performance and emissions of a compression ignition (CI) engine, using waste plastic oil, were tested and compared with using diesel oil. The physical characteristics, gross calorific value (MJ/kg), kinematic viscosity cst @40°C, specific gravity @15.6°C, cetane index, flash point and distillation temperature @90 per cent are determined. The experimental CI engine is a four-stroke, direct injection, single cylinder, 709 C.C. and has been tested with in-brake-specific fuel consumption (BSFC), brake conversion efficiency, brake-specific energy consumption and exhaust gas emissions.

The results show that the characteristics of liquid fuel from landfill plastics (LFLP3) are similar to diesel oil. The CI engine was able to run with LFLP3. The efficiency was slightly higher than that of diesel fuel, whereas the BSFC was lower. The exhaust-gas emission average for LFLP3 was reduced compared to diesel oil operation.

The efficiency of the CI engine using LFLP3 is slightly higher than diesel fuel at all load conditions. In this study, LFLP3 was a lower pollutant than diesel fuel. Environmental values and energy consumption are important when reviewing the ignition of any fuel in a combustion chamber.

The efficiency of the CI engine using LFLP3 is slightly higher than diesel fuel at all load conditions. In this study, LFLP3 was a lower pollutant than diesel fuel. Environmental values and energy consumption are important when reviewing the ignition of any fuel in a combustion chamber.

The effective heat capacity is a key index to estimate the thermal protection performance of charring ablative materials in reentry vehicles subjected to aerodynamic heat loads. The purpose of this paper is to investigate the effects of gradient density on the effective heat capacity.

Based on the Fourier law and the pyrolysis interface model, the authors establish the governing equations for the transient heat conduction with variable density, and then simulate one-dimensional transient thermal behavior of a homogeneous and three types of non-homogeneous charring ablative material in reentry capsules by using the implicit numerical method.

The moving rate of pyrolysis interface and the surface temperature of charring ablative material depend on not only the surface heating history, but also the gradient density. And the gradient density can improve the insulation performance of charring materials, e.g. the effective heat capacity in the bilinear design is larger than that in the homogeneous design under a given heat flux condition.

This study will help the design of the thermal protection system in reentry vehicles.

Purpose – This work aims to study the treatment of adsorbant on the increasing liquid hydrocarbon quality produced by pyrolysis low density polyethylene (LDPE) plastic waste at low temperature. The hydrocarbon distribution, physicochemical properties and emission test were also studied due to its application in internal combustion engine. This research uses pure Calcium carbonate (CaCO₃) and pure activated carbon as adsorbant, LDPE type clear plastic samples with control variable that is solar gas station.

Design/Methodology/Approach – LDPE plastic waste of 10 kg were vaporized in the thermal cracking batch reactor using LPG 12 kg as fuel at range temperature from 100 to 300°C and condensed into liquid hydrocarbon. Furthermore, this product was treated with the mixed CaCO₃ and activated carbon as adsorbants to decrease contaminant material.

Findings – GC-MS identified the presence of carbon chain in the range of C6–C44 with 24.24% of hydrocarbon compounds in the liquid. They are similar to diesel (C6–C14). The 30% of liquid yields were found at operating temperature of 300°C. The calorific value of liquid was 46.021 MJ/Kg. This value was 5.07% higher than diesel as control.

Originality/Value – Hydrocarbon compounds in liquid produced by thermal cracking at a low temperature was similar to liquid from a catalytic process.

The authors aim to investigate the use of pyrolysis for the processing of waste printed circuit boards (PCBs). The aim was to make the process of separating the organic, metallic, and glass fibre fractions of PCBs much easier and therefore make recycling of each PCB fraction more viable.

The PCBs were pyrolysed in a fixed bed reactor at 850°C. The organic fraction released by the boards was analysed by a variety of gas chromatography techniques. The residue that remained after pyrolysis was analysed by ICP‐MS to determine the type of metals that were present.

When PCBs were heated to 800°C in an oxygen free atmosphere, the organic fraction decomposed to form volatile oils and gases leaving behind the metal and glass fibre fraction of the boards. The pyrolysed boards were very friable and the different fractions (metal components, copper power boards, glass fibre, etc.) could be easily separated. The recovered metals could then be recycled by traditional routes with particular emphasis being placed on the recovery and recycling of rare and precious metals. The organic oils and gases which are produced during pyrolysis of PCBs can either be used as a chemical feedstock or as a fuel.

The research was only carried out on a very small scale so an investigation into scale‐up must be performed.

By using pyrolysis, the organic and metallic fraction of PCBs can be separated and recycled.

This paper presents a novel method for resource recovery from PCBs.

This study aims to investigate the effect of reactor temperature on softwood and hardwood pyrolysis. Experiments are performed at six temperature levels ranging from 300 to 800°C under N₂ atmosphere. The weights of char, tar and gas yields produced were measured and recorded in percentage of initial weight of the pyrolyzed samples. Results of the study showed that hardwood produces maximum char, tar and gas yields of 41.02 per cent at 300°C,44.10 per cent at 300°C and 56.86 per cent at 800°C, respectively, whereas softwood produces maximum yields of 30.10 per cent at 300°C, 28.25 per cent at 300°C and 68.73 per cent at 800°C, respectively. Proximate analysis shows that volatile matter, fixed carbon, ash content and moisture content of hardwood are 74.83, 14.28, 2.81 and 8.08 per cent, respectively, and that of softwood are 79.76, 12.65, 0.98 and 6.61 per cent, respectively. Result of the elemental analysis results shows that the carbon, hydrogen, nitrogen, oxygen and sulphur contents for hardwood are 52.20, 6.45, 0.68, 39.64 and 1.03 per cent, respectively, and that of softwood are 45.95, 4.57, 0.56, 48.13 and 0.79 per cent, respectively. The higher heating value of hardwood and softwood are 21.76 and 16.50 kJ/g respectively. This study shows that char and tar yields decrease with increase pyrolysis temperature, whereas gas yield increases as pyrolysis temperature increases for the wood samples considered. At all temperatures considered in this study, gas yields are higher than tar and char yields for softwood, whereas for hardwood, tar yield decreases with increase in temperature with accompanying increase in gas yield.

Experiments are performed at six temperature levels ranging from 300 to 800°C under N₂ atmosphere.

At all temperatures considered in this study, gas yields are higher than tar and char yields for softwood, whereas for hardwood, tar yield decreases with increase in temperature with accompanying increase in gas yield.

Results of the study showed that hardwood produces maximum char, tar and gas yields of 41.02 per cent at 300°C,44.10 per cent at 300°C and 56.86 per cent at 800°C, respectively, whereas softwood produces maximum yields of 30.10 per cent at 300°C, 28.25 per cent at 300°C and 68.73 per cent at 800°C, respectively.

This work experimentally and numerically investigates the aerodynamic heating of the charring‐ablating materials.

The experimental model is a stainless steel cone with an attached charring ablator, in which supersonic hot flow impinges. The initial numerical simulation is based on physical and mathematical models, including one‐dimensional, unsteady energy transport and mass conservation equations, coupled with calculations of aerodynamic heating, thermal degradation, heat transfer of the ablating surface and the ablation model. The problem is solved by an efficient numerical method.

The numerical calculations involve the time history of the temperature distribution inside the charring material and the backup structure. The results are consistent with the experimental data.

This study proposes an effective method to correlate one's own ablation rate equation, by a method of trial and error to find the correlation constants, and the corresponding time histories of the ablation rate or temperature that are closest to one's own experimental data. Then the correlation of the surface ablation rate can be applied with confidence in the numerical calculation of other cases.

The purpose of this paper is to synthesise carboxymethylcellulose and methyl methacrylate graft copolymers (CMC‐g‐PMMA), which is used as an effective additive, for reinforcing the rice‐hull‐cement composite.

Various CMC‐g‐PMMA copolymers were synthesised at different reaction temperatures, pH values of reaction solution and the dosages of monomer and initiator (potassium persulphate). The copolymers were characterised by Fourier transforms infrared (FT‐IR) spectra, thermal analysis (thermogravimetric and differential scanning calorimeter), X‐ray diffractometry (XRD) and scanning electron microscopy.

An optimal CMC‐g‐PMMA copolymer is obtained. For synthesis of the CMC‐g‐PMMA, the optimal reaction temperature is 80°C and pH value is 9. FT‐IR test of CMC‐g‐PMMA confirmed the existence of a chemical link between carboxymethylcellulose (CMC) and methyl methacrylate (MMA). The content of initiator has little effect on the reaction for synthesising the graft copolymer. Thermal analysis indicates the occurrence of graft reaction in CMC and MMA. XRD test proved that the chains of the graft copolymer can enlarge the proportion of the amorphous regions of CMC. Adding MMA has damage effect on the crystallisation.

Since the results of this paper are obtained from the laboratory experiments, further research should be conducted for evaluating the performances of this copolymer in practical application.

The mechanical test of the rice‐hull‐cement composite proved that CMC‐g‐PMMA is an effective additive for reinforcing the rice‐hull‐cement composite. The synthesis of CMC‐g‐PMMA provides a new alternative for modifying cellulose derivatives.

The CMC‐g‐PMMA obtained in this paper is a new kind of effective agent. It can reinforce the rice‐hull‐cement composite and expands the application of the composite in building industries.

The purpose of this paper is to use the natural wastage plant product, bannana pseudostem sap (BPS) for using as fire retardant of cellulosic textile substrate. The study aims to use first time any wastage plant product for making fire retardant cellulosic textile. In this regard flame retardant functionality was imparted in cellulosic textile using BPS, an eco-friendly natural wastage product.

The extracted sap was made alkaline and applied in pre-mordanted bleached and mercerized cotton fabrics. Flame retardant properties of the control and treated fabrics were analyzed in terms of limiting oxygen index (LOI), horizontal and vertical flammability and total heat of combustion using bomb calorimeter. The thermal degradation and pyrolysis was studied using thermogravimetric analysis (TGA). The chemical composition of the control and BPS treated cellulosic fabric were analyzed by FTIR, SEM and EDX. Durability of the flame retardant functionality to soap washing had also been studied.

The study showed that the treated fabrics had good flame retardant property compared to control fabrics. The LOI value was found to increase by 1.6 times after application of BPS. As a result of this, the fabric does not catch flame. In horizontal flammability, the treated fabric showed burning with afterglow (without presence of flame) with a propagation rate of 7.5 mm/min, which is almost ten times lower than the control fabric. After application of BPS cellulosic fabric sample produced natural khaki colour. There was no significant change in other physical properties.

The application process is simple and cost-effective as no costly chemicals were used. Further advantage is that the treated fabric could also be considered as natural dyed cotton fabric. The developed khaki colour is quite attractive and stable to sun light exposure. This developed process could used in colouration and flame retardant finishing of home furnishing products such as home-window curtain, railway curtain, hospital curtain, table lamp and as a covering material of non-permanent structure like in book fair, festival, religious purpose, etc., where large quantity of textile is used and has chance of fire hazards.

BPS abundantly available in Indian as well as other countries and it is normally considered as waste material. It is eco-friendly and produced from renewable source. Therefore, the application of BPS in cotton textile for colouration and functionalization will give the advantages of value addition using natural product. Rural people will be benifited lot by applying this technology whenever it required.

This paper helps to clarify first time why and how a wastage plant product like BPS can be used for preparing fire retardant cotton cellulosic fabric.