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Introduction: The current work aims to investigate the presence of petrol, kerosene, diesel and motor oil on four kinds of exhibits: paper, cloth, wood and cotton after their partial burning. The purpose of this study is to enlighten the choice of selection of target exhibits at the arson scene that will surely serve the detection of ignitable liquids. Materials and Methods: The experimentation was performed after preparing 20 samples from the obtained 20 exhibits after the 2 days of procurement of using the n-hexane for extraction followed by the analysis on an indispensable tool named GC-FID. Results: Based on the physio-chemical properties of petroleum products along the characteristics of the exhibits, positive results have been obtained indicating the presence of petroleum products in the samples highlighting the detection levels ranging from low to intermediate to high degrees. Low level of petrol has been detected in paper indicating due to less adsorption stimulates the evaporation of petrol to greater extent than from the other exhibits. On the contrary, best results have been encountered for petrol detection from cotton and cloth (made up of Cotton fabric) reflecting the good retention capacity and the best material to select at the time of collection of fire debris. [ABSTRACT FROM AUTHOR]

A new process for the production of bioethanol from paper mill sludge (PMS) is described in this work. PMS biomass feedstock was processed via the simultaneous saccharification and fermentation (SSF) with and without accelerants. The enzymatic hydrolysis and fermentation were first evaluated, and the energy demand was 2.2 MJ/L of produced ethanol. When the enzymatic hydrolysis and fermentation were combined, the energy demand was reduced to 1.0 MJ/L ethanol, the sugars production increased, and the overall capital cost of the process decreased. The sugar yield was improved by adding accelerant and selecting the optimal fiber recovery method. The accelerant improved the enzymatic hydrolysis via a pathing/bridging mechanism. The SSF with the chemical fiber recovery method coupled with accelerant addition would be the best process configuration. Upon this combination, the glucose profile was enhanced from 9.8 g/L to 17.0 g/L. The sludge fiber conversion by SSF was improved by selecting an efficient fiber recovery method combined with the accelerant addition. SSF in chemical fiber recovery with accelerant addition was the best process by a 10% improvement of ethanol yield. The proposed process configuration offers a lower cost and sustainable process and contributes to the circular economy of zero waste discharges. • A combined SSF process using PMS feedstock to produce bioethanol was developed. • The energy saving in an integrated process was 1.2 MJ/L ethanol. • The optimal fiber recovery from paper mill sludge was achieved via acid treatment. • The optimal fiber recovery increased fractional glucose by 27%. • The cationic accelerant improved the enzymatic hydrolysis by 10% due to the patching mechanism. [ABSTRACT FROM AUTHOR]

One can take advantage of the striking similarity of ignitable liquid vaporization (or weathering) patterns and the separation observed during distillation to predict the composition of residual compounds in fire debris. This is done with the advanced distillation curve (ADC) metrology, which separates a complex fluid by distillation into fractions that are sampled, and for which thermodynamically consistent temperatures are measured at atmospheric pressure. The collected sample fractions can be analyzed by any method that is appropriate. Analytical methods we have applied include gas chromatography (with flame ionization, mass spectrometric and sulfur chemiluminescence detection), thin layer chromatography, FTIR, Karl Fischer coulombic titrimetry, refractometry, corrosivity analysis, neutron activation analysis and cold neutron prompt gamma activation analysis. We have applied this method on product streams such as finished fuels (gasoline, diesel fuels, aviation fuels, rocket propellants), crude oils (including a crude oil made from swine manure) and waste oils streams (used automotive and transformer oils). In this paper, we present results on a variety of ignitable liquids that are not commodity fuels, chosen from the Ignitable Liquids Reference Collection (ILRC). These measurements are assembled into a preliminary database. From this selection, we discuss the significance and forensic application of the temperature data grid and the composition explicit data channel of the ADC. [ABSTRACT FROM AUTHOR]

With the rising demand for renewable energy and environmental protection, anaerobic digestion of biogas technology has attracted considerable attention within the scientific community. This paper presents a comprehensive review of research achievements on anaerobic digestion developments for biogas production. The review includes a discussion of factors affecting efficiency (temperature, pH, C/N ratio, OLR and retention time), accelerants (greenery biomass, biological pure culture and inorganic additives), reactors (conventional anaerobic reactors, sludge retention reactors and anaerobic membrane reactors) and biogas AD processes (lignocellulose waste, municipal solid waste, food waste, livestock manure and waste activated sludge) based on substrate characteristics and discusses the application of each forementioned aspect. The factors affecting efficiency are crucial to anaerobic digestion, because they play a major role in biogas production and determine the metabolic conditions for microorganism growth. As an additive, an accelerant is not only regarded as a nutrient resource, but can also improve biodegradability. The focus of reactor design is the sufficient utilization of a substrate by changing the feeding method and enhancing the attachment to biomass. The optimal digestion process balances the optimal digest conditions with the cost-optimal input/output ratio. Additionally, establishment of theoretical and technological studies should emphasize practicality based on laboratory-scale experiments because further development of biogas plants would allow for a transition from household to medium- and large-scale projects; therefore, improving stability and efficiency are recommended for advancing AD research. [ABSTRACT FROM AUTHOR]

The detection of ignitable liquid residues (ILRs) at a fire scene can be valuable evidence to indicate if the fire may have been deliberately set. In this study, a commercially-available portable GC-MS, the TRIDION-9, was evaluated for the purpose of on-site fire debris analysis. The instrument, which incorporates a low thermal mass capillary GC and a miniaturised toroidal ion trap mass spectrometer, is designed to use solid-phase microextraction (SPME) as the default sampling method. Four ignitable liquids (petrol, mineral turpentine, kerosene and diesel) and seven substrates (nylon, polypropylene and wool carpet, rubber and foam underlay, untreated pine and polyurethane) were considered. After method optimisation, substrates were burned and spiked with 0.1 μL of ignitable liquid (mineral turpentine, kerosene, diesel fuel, and both neat and weathered unleaded petrol). Sampling was performed via passive headspace SPME adsorption over 3 min immediately followed by analysis using the TRIDION-9 (analysis time < 2 min). Field trials were performed on fire debris samples collected from an accelerated structural fire. The data from the portable GC-MS analyses permitted the detection and correct classification of ILRs in the majority of samples analysed. Overall, the TRIDION-9 was found to be well-suited to the field-based analysis of fire debris samples as a preliminary screen to provide rapid presumptive results for fire investigators. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether gasoline residues could be detected post-mortem in lung tissue and heart blood of fire victims. The lungs and heart blood were investigated to determine whether they were suitable samples for collection and could be collected without contamination during an autopsy. Three sets of test subjects (pig carcasses) were investigated under two different fire scenarios. Test subjects 1 were anaesthetized following animal ethics approval, inhaled gasoline vapours for a short period and then euthanized. The carcasses were clothed and placed in a house where additional gasoline was poured onto the carcass post-mortem in one fire, but not in the other. Test subjects 2 did not inhale gasoline, were clothed and placed in the house and had gasoline poured onto them in both fires. Test subjects 3 were clothed but had no exposure to gasoline either ante- or post-mortem. Following controlled burns and suppression with water, the carcasses were collected, and their lungs and heart blood were excised at a necropsy. The headspace from the samples was analysed using thermal desorption-gas chromatography-mass spectroscopy. Gasoline was identified in the lungs and heart blood from the subjects that were exposed to gasoline vapours prior to death (test subjects 1). All other samples were negative for gasoline residues. These results suggest that it is useful to analyse for volatile ignitable liquids in lung tissue and blood as it may help to determine whether a victim was alive and inhaling gases at the time of a fire. [ABSTRACT FROM AUTHOR]

A solid-phase microextraction (SPME) procedure involving direct contact between the SPME fibers and the solid matrix and subsequent gas chromatography/mass spectrometric analysis for the detection of accelerants in fire debris is described. The extraction performances of six fibers (100 μm polydimethylsiloxane, 65 μm polydimethylsiloxane-divinylbenzene, 85 μm polyacrylate, 85 μm carboxen-polydimethylsiloxane, 70 μm Carbowax-divinylbenzene, and 50/30 μm divinylbenzene-Carboxen-polydimethylsiloxane) were investigated by directly immersing the fibers into gasoline, kerosene, and diesel fuel. For simulated fire debris, in the direct contact extraction method, the SPME fiber was kept in contact with the fire debris matrix during extraction by penetrating plastic bags wrapping the sample. This method gave comparable results to the headspace SPME method in the extraction of gasoline and kerosene, and gave an improved recovery of low-volatile components in the extraction of diesel fuel from fire debris. The results demonstrate that this procedure is suitable as a simple and rapid screening method for detecting ignitable liquids in fire debris packed in plastic bags. [ABSTRACT FROM AUTHOR]