Effects of the type of biomass and ashing temperature on the properties of solid fuel ashes

Ashes were prepared by annealing selected types of solid fuels (biomass: corn cobs, sunflower husks, olive pomace, hay pellets and rice husks; coal: lignite and bituminous; and alternative fuel: paper sludge) at different temperatures (550 degrees C, 815 degrees C and 975 degrees C). Based on X-ray fluorescence spectra, the slagging/fouling indexes were used to study the effects of the type of ash and the ashing temperature on the ash fouling and slagging properties. Slagging indexes were compared with the ash fusion temperatures. Ash fusion temperatures were measured by a LECO AF-700. The lowest deformation temperature (below 1000 degrees C) was seen for the ashes prepared from hay pellets and corn cobs. On the other hand, the deformation temperature exceeded 1500 degrees C for ashes prepared from paper sludge, sunflower husks and rice husks. By calculating the different slagging/fouling indexes, all the ashes exhibited slagging/fouling problems of varying degrees.Web of Science212514

Effect of column bleed on trueness of high-resolution mass spectrometric determination of dibenzo-p-dioxins, dibenzofuranes, and polychlorinated biphenyls

Effect of column bleed on trueness of determination of trace levels of dibenzofuranes (PCDD/F) and biphenyls (PCB) by gas chromatography-high-resolution mass spectrometry (GC-HRMS) was studied. As a result of extensive bleed of an arylenesiloxane capillary column, fluctuations of abundance ratios of monitored ions were observed, making exact determination of target analytes impossible. These effects were observed on food samples as well as on pure standard mixtures. The column bleed affected the abundance ratios of PCDD/F and PCB within the range of 13–328 pg of target analyte/mL, and higher levels of analytes remained intact. An analysis of diluted calibration mixtures is recommended as a tool for detection of column bleed.Web of Scienc

The impact of co-combustion of polyethylene plastics and wood in a small residential boiler on emissions of gaseous pollutants, particulate matter, PAHs and 1,3,5-triphenylbenzene

The aim of this study was to simulate a banned but widely spread practice of co-combustion of plastic with wood in a small residential boiler and to quantify its impact on emissions of gaseous pollutants, particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), and 1,3,5-triphenylbenzene (135TPB), a new tracer of polyethylene plastic combustion. Supermarket polyethylene shopping bags (PE) and polyethylene terephthalate bottles (PET) were burnt as supplementary fuels with beech logs (BL) in an old-type 20 kW over-fire boiler both at a nominal and reduced heat output. An impact of co-combustion was more pronounced at the nominal heat output: an increase in emissions of PM, total organic carbon (TOC), toxic equivalent (TEQ) of 7 carcinogenic PAHs (c-PAHs) and a higher ratio of c-PAHs TEQ in particulate phase was observed during co-combustion of both plastics. 135TPB was found in emissions from both plastics both at a nominal and reduced output. In contrast to findings reported in the literature, 135TPB was a dominant compound detected by mass spectrometry on m/z 306 exclusively in emissions from co-combustion of PE. Surprisingly, six other even more abundant compounds of unknown identity were found on this m/z in emissions from co-combustion of PET. One of these unknown compounds was identified as p-quaterphenyl (pQ). Principal component analysis revealed strong correlation among 135TPB, pQ and five unknown compounds. pQ seems to be suitable tracers of polyethylene terephthalate plastic co-combustion, while 135TPB proved its suitability to be an all-purpose tracer of polyethylene plastics combustion.Web of Science196241

Effects of the type of biomass and ashing temperature on the properties of solid fuel ashes

Ashes were prepared by annealing selected types of solid fuels (biomass: corn cobs, sunflower husks, olive pomace, hay pellets and rice husks; coal: lignite and bituminous; and alternative fuel: paper sludge) at different temperatures (550°C, 815°C and 975°C). Based on X-ray fluorescence spectra, the slagging/fouling indexes were used to study the effects of the type of ash and the ashing temperature on the ash fouling and slagging properties. Slagging indexes were compared with the ash fusion temperatures. Ash fusion temperatures were measured by a LECO AF-700. The lowest deformation temperature (below 1000°C) was seen for the ashes prepared from hay pellets and corn cobs. On the other hand, the deformation temperature exceeded 1500°C for ashes prepared from paper sludge, sunflower husks and rice husks. By calculating the different slagging/fouling indexes, all the ashes exhibited slagging/fouling problems of varying degrees

Change in the wood moisture dependency on time and drying conditions for heating by wood combustion

The aim of this study was to determine the drying time of firewood under the climatic conditions of the Czech Republic to decrease the moisture content to an acceptable level for combustion (under 20%). The effects of log size, outdoor/indoor drying and wood species were evaluated.Web of Science63227226

Impact of boiler type, heat output, and combusted fuel on emission factors for gaseous and particulate pollutants

Five different boiler types (automatic boiler, overfire boiler, boiler with down-draft combustion, and two types of gasification boilers) representing residential-scale combustion technology were tested. Boilers were fueled with various fuels (lignite, wet and dry wood, wood pellets, and mixed fuel), and the combustion emissions were measured both at nominal and reduced output. The investigated emissions comprised CO, organic gaseous compounds (OGC), and particulate matter (PM). A cyclone and a low-pressure impactor were used to determine PM emissions. It was found that the emission factors for CO, OGC, and PM depend more on boiler type and mode of operation (reduced or nominal output) than on fuel type. Data from the Dekati low-pressure impactor (DLPI) show that, in most cases, PM1 represents approximately 80% of the total PM mass. PM0.1 represents 15-30% (modern boilers) or 5-10% (old-type boilers) of the total PM mass. Comparison of the results shows that the emission factors for PM obtained by the cyclone were higher than the emission factors obtained using the DLPI.Web of Science30108456844