Fire hazard and heat of combustion of sunflower seed hull pellets

This study is concerned with the investigation of the impact of heat flux on the fire hazard and the effective heat of combustion of sunflower seed hull pellets. Pellets produced by pressing common sunflower seed hulls (Helianthus annuus L.) were investigated. The samples were dried on water content of 0 mass% at a temperature of 103 ± 2 °C. The fire hazard and the heat of combustion have been determined via the cone calorimeter and by the testing procedure per ISO 5660-1:2015 at three heat fluxes (25, 35 and 50 kW m⁻²). The peak heat release rate increases with the increasing of the heat flux from 446 (at a heat flux of 25 kW m⁻²) to 601 kW m⁻² (at a heat flux of 50 kW m⁻²). The carbon monoxide yield lies in the interval from 82.50 (at a heat flux of 25 kW m⁻²) to 154.15 g kg⁻¹ (at a heat flux of 50 kW m⁻²). The effective heat of combustion decreases with the increasing of the heat flux from 15.84 (at a heat flux of 25 kW m⁻²) to 14.58 MJ kg⁻¹ (at a heat flux of 50 kW m⁻²).

     

Thermogravimetric analysis of cellulose insulation and determination of activation energy of its thermo‐oxidation using non‐isothermal,model‐free methods

The aim of the work was to determine the effect of heating rate on initial decomposition temperature and phases of thermal decomposition of cellulose insulation. The activation energy of thermo‐oxidation of insulation was also determined. Individual samples were heated in the air flow in the thermal range of 100°C to 500°C at rates from 1.9°C min^?1 to 20.1°C min^?1. The initial temperatures of thermal decomposition ranged from 220°C to 320°C, depending on the heating rate. Three regions of thermal decomposition were observed. The maximum rates of mass loss were measured at the temperatures between 288°C and 362°C. The activation energies, which achieved average values between 75 and 80.7 kJ mol^?1, were calculated from the obtained results by non‐isothermal, model‐free methods. Copyright © 2014 John Wiley & Sons, Ltd.     

Calculation of charring rate and char depth of spruce and pine wood from mass loss

Journal of Thermal Analysis and Calorimetry - A charring rate is a key parameter for the calculation of fire resistance of timber structures and for fire investigation. Charring rates are...     

Assessing the fire risk of electrical cables using a cone calorimeter

Journal of Thermal Analysis and Calorimetry - The presented study deals with the fire risk of electrical cables. Samples of three-core electrical power cables and two-core electrical control cables...     

The recognition of selected burning liquids by convolutional neural networks under laboratory conditions

Journal of Thermal Analysis and Calorimetry - This paper deals with the recognition of selected burning liquids by convolutional neural networks (CNNs). Three CNNs (AlexNet, GoogLeNet and...     

Calorific value and fire risk of selected fast-growing wood species

This study deals with heat of combustion of selected fast-growing woods. The study also investigates the impact of heat flux on fire risk of the selected fast-growing woods. The hybrid poplar J-105 (Populus nigra × P. maximowiczii), white willow (Salix alba L.) and black locust (Robinia pseudoacacia L.) woods were measured. The heats of combustion were determined by a bomb calorimeter. Fire risk was evaluated with a cone calorimeter at different heat fluxes. The net heat of combustion occurred in the interval from 17.68 MJ kg^?1 (black locust) to 18.02 MJ kg^?1 (hybrid poplar). Fire risk was assessed on the basis of the critical heat flux, maximum average rate of heat emission, carbon monoxide yield, smoke yield and time to flashover. The hybrid poplar had the lowest critical heat flux (12.8 kW m^?2), and the white willow had the highest critical heat flux (17.4 kW m^?2). The maximum average rate of heat emission and the smoke yield increased with the increasing heat flux. On the other hand, carbon monoxide yield decreased with the increasing heat flux. The differences between the times to flashover of the measured wood species were not significant.