Dataset on flue gas composition during combustion in the fluidised bed reactor. Polyethylene combustion

The dataset presented in this article is the supplementary data for the research article titled “The combustion of polyolefins in the inert and catalytic fluidised beds”, in which polyethylene combustion in the cenosphere fluidised bed were investigated. The use of cenospheres as a bed material made it possible to free sink of PE particles in the bed and rule out its combustion in freeboard. It also lead to elimination of soot formation. The quantitative and qualitative analysis of flue gases were performed by Fourier Transform Infrared Spectroscopy (FTIR, Gasmet DX-4000). This data article provides detailed information on changes in product concentration at intervals of a few seconds.


Value of the data
The data provides detailed information on the quality and quantity of products of polyethylene degradation as a function of time. This dataset will be helpful to develop the kinetic models of polyethylene combustion in inert or catalytic (Fe 2 O 3 ) fluidised beds. The data may be also used to the development of modelling of RDF combustion in fluidised bed. Data from a real object will be of interest to engineers and scientists involved in modelling, among others from, Berkeley University of California [2] , Politecnico di Milano [3] , Lawrence Livermore National Laboratory [4] , University of Southern California [5] .

Data description
Correct modeling requires data from real objects. Ekpe Moses [6] used the data presented in the works [ 7 , 8 ] and created a simulation model of electricity production from the High Density Polyethylene (HDPE) waste. Thanks to that a theoretical framework for a waste plastic power plant using HDPE as the feed was proposed even though data from a real-life waste plastic power plant were not available. Shi et al. [9] undertook the numerical simulation of HDPE combustion because the fire risk of non-charring polymers is a big problem in civil engineering. That numerical results were validated by cone calorimeter experiments under spontaneous ignition condition. Fluidised bed combustion of polyethylene is interesting due to the use of Refuse-Derived Fuel (RDF) to generate energy.
In the related research article [1] an innovative fluidised bed made from cenospheres has been used. The use of cenospheres (0.845 g.cm 3 ) made it possible to obtain a bed with a density comparable or smaller to that of polyethylene (0.92-0.96 g/cm 3 ). Such innovation had a crucial influence on combustion because diffusion combustion in the freeboard was eliminated. Even higher fuel conversion at lower temperatures and the elimination of explosions have been achieved by the catalytic combustion process using Fe 2 O 3 -cenospheres. The composition of flue gas during PE combustion in fluidised beds of cenospheres and Fe 2 O 3 -cenospheres was monitored online by FTIR analyser.
This work presents data from a real fluidised bed combustor. The data presents the composition of flue gas during polyethylene combustion. The dataset contains 31 Tables. Table 1 contains the parameters of the reactor, bed material, and fluidising gas. Tables 2-31 provide information on the change in concentration of emitted components as a function of time during, PE, LLDPE, HDPE fluidised bed combustion.

Experimental design, materials, and methods
Fluidised bed reactor with an inner diameter of 96 mm was filled by 300 g cenospheres. Two kinds of cenospheric beds were tested. Inert cenospheres -a fraction of raw cenospheres but selected so that the shells of the spheres have not broken and perforated surfaces. Catalytic cenospheres were covered by Fe 2 O 3 (12,5% mass ). Inert and catalytic cenospheres have diam. 0.25-0.3 mm. Bed materials were introduced into fluidised bed by air. Thermal degradation of polyethylene samples was carried out at five bed temperatures: from 500 to 900 °C, at 100 °C intervals. Three types of polyethylene samples were tested: PE, HDPE, LLDPE. Samples ( ≈ 200 mg) were thrown from the top of the reactor. Video recording of the bed surface and audio analysis have proven polymer sinking and degradation inside the bed. Released gases were sampled by a probe form freeboard zone. The gas path was heated to 180 °C. Infrared analyses were performed on-line during fluidised bed combustion. The recording of the spectrum and its deconvoluting took 7-8 seconds. Calcmet software (Gasmet Technologies Oy) uses a modified leastsquares method to determine the appropriate concentrations of compounds in the sample based on a set of reference spectra. This method is modified by additional masking of certain ranges of reference spectra. The analyzes were performed based on the following reference compound spectra (with detailed analysis ranges of wavenumber): H 2 O (340 0 -320 0 cm −1 ); CO 2 3257-3723 cm −1 ); CO (20 0 0-220 0 cm −1 and 2540-2590 cm −1 ); methane (260 0-320 0 cm −1 ); ethane (260 0-320 0 cm −1 ); propane (260 0-320 0 cm −1 ); ethylene (910-1150 cm −1 ); hexane (260 0-320 0                   cm −1 ); formaldehyde (2550-2850 cm −1 ); acetaldehyde (2550-2950 cm −1 ); acrolein (2550-2900 cm −1 ); acetylene 2995-3412 cm −1 ); benzene (2856-3226 cm −1 ); methanol 910-1150 cm −1 and 2550-2920 cm −1 ); formic acid (895-1192 cm −1 ); acetic acid (895-1335 cm −1 ); acetone (895-1380 cm −1 ). Selected wavenumbers indicated characteristic absorbance bands of given compounds resulting from its specific structure. The deconvolution method for the quantification of the concentration of compounds in the flue gases during the FTIR analysis was explained in the supplementary material for the article [10] . The Calcmet software collects, stores spectra of the sample gas, and analyzes the concentrations of the flue gas components. The apparatus performed 50 scans per second in the range of wavenumber 90 0-420 0 cm −1 . The results of the analysis were copied from the Calcmet text file and were pasted into the manuscript as tables. Columns referring to undetected compounds were removed. Concentration changes over time are summarized in Tables 2-16 and 17-31 , respectively, for inert and catalytic bed.