A Technical Analysis of Solid Recovered Fuel from Torrefied Jatropha Seed Residue via a Two-Stage Mechanical Screw Press and Solvent Extraction Process

This study investigated the torrefaction of de-oiled Jatropha seed residue after a two-stage sequential process consisting of mechanical screw pressing and solvent extraction using n-hexane (denoted as JMS). The optimal torrefaction temperature (Tr) and torrefaction time (tr) were determined in the ranges of 260–300 °C and 10–60 min, respectively, so to achieve a better heating value and satisfactory energy densification (ED) with acceptable mass loss. Thermogravimetric analysis was employed to elucidate the thermal decomposition behaviors of JMS. By comparison with the torrefaction of Jatropha seed residue after mechanical oil extraction by screw pressing only (namely, JMET), the results indicated that the ED of the torrefaction of JMS yielding the torrefied product JMST (two-stage product) was higher than that of the torrefaction of JME giving the torrefied product JMET (single-stage product). Further, it was found that JMET contained some tar, which was attributed to a thermal reaction in the residual oil in JME during torrefaction. The tar/oil content of JMET was about 1.0–1.8 wt.% in the determined optimal conditions. Thus, the enhanced recovery of the residual oil is advantageous not only because it allows obtaining more oil from Jatropha seed residue with a positive net energy gain but also because it prevents the formation of tar in torrefied biomass products.

Numerical analysis of soil microstructure reveals conditions for natural attenuation in aged tar oil contaminated soil

<p>Understanding of ongoing biogeochemical processes (natural attenuation) within contaminated soils is crucial for the development of plausible remediation strategies. We studied a tar oil contaminated soil with weak grass vegetation at a former manufactured gas plant site in Germany. Despite of the apparent toxicity (the soil contained up to 120 g kg<sup>-1</sup> petroleum hydrocarbons, 26 g kg<sup>-1</sup> toxic metals, and 100 mg kg<sup>-1</sup> polycyclic aromatic hydrocarbons), the contaminated layers have 3-5 times as much cell counts as an uncontaminated control soil nearby. To test, if the geometry of the pore space provides favourable living space for microorganisms, we applied scanning electron microscopy to the thin sections and calculated on sets of 15 images per layer three specific Minkowski functionals, connected to soil total porosity, interface, and hydraulic parameters.</p><p>Our investigation showed that the uncontaminated control soil has a relatively low porosity of 15-20 %, of which 50-70 % is comprised of small (< 15 µm) pores. These pores are poorly connected and show high distances between them (mean distance to the next pore 10 µm). The dominating habitats in the control soil are therefore created by small pores. They provide good protection from predators and desiccation, but input of dissolved organic C and removal of metabolic products are diffusion limited. Coarser pores (>15 µm) provide less space (< 50 % of total porosity) and solid surface area (< 20 %), are prone to desiccation and offer less protection from predators. However, they serve as preferential flow paths for the soil solution (input of nutrients) and are well aerated, therefore we expect the microbial activity in them to appear in “hot moments”, i.e. after rain events.</p><p>All layers of the contaminated profile have higher porosities (20-70 %) than the control. Coarse pores comprise 83-90 % of total pore area and create 34-52 % of total interface. Pores are also more connected and tortuous than in the control soil, which implies a better aeration and circulation of soil solution. The loops of pore channels may retain soil solution and be therefore preferably populated with microorganisms. The small (< 15 µm) pores comprise less than 17 % of total porosity but represent a substantial proportion of the interface (48-66 % vs 82-91 % in control). In the uppermost layer of the contaminated profile, such pores occur in plant residues, are close to the largest pores (mean distance to the next pore 4 µm) and therefore, along with good protection, are supplied with air, water, and non-tar C. In the middle of the profile, the small pores, presumably constantly filled with water, are located within dense tar pieces remote from the neighbouring pores (mean distance to the next pore 22 µm), and therefore, with hindered aeration and no supply of non-tar C, may create anaerobic domains of tar attenuation.</p><p>Our results show that the contaminated soil offers more favourable conditions for microorganisms than the control soil, probably because the hydrocarbons provide suitable energy and nutrition sources and a beneficial pore space geometry.</p>

Study of the influence of technological parameters of the cooking process on the quality of coal tar produced in com ovens “ArcelorMittal Temirtau” JSC

In the article there are presented results of a research that was carried out to determine a reason for the increase of more than 1,22 g/cm3 coal-tar oil density at the coke production of “ArcelorMittal Temirtau” joint-stock company. There have been studied samples of coal concentrates from nine layers of eight mines in Karaganda coal basin and GZh coal concentrate which are supplied to the coke chemical production of “ArcelorMittal Temirtau” joint-stock company from “Kunetskaya” Enrichment plant (Russia). During the work there has been determined dependence of the gas composition on the temperature affecting gas that was released during coal carbonizing process. It is experimentally established that with an increase in the temperature of the released coke gas above 750 ° C to 1000 ° C, light fractions evaporate from the resin and are removed into the gas discharge path, which is accompanied by a weighting, an increase in the density captured for processing coal tar into pitch. The results of the resin studies that is isolated in the same temperature ranges show the indicators of the resin yield and its density during the tests of concentrates also follow a certain pattern – with an increase in the coal carbonizing temperature and with overheating of the released gas, the resin density increases and its yield decreases. The researches in the plant has found that the technological reason for the weighting of the coke gas resin is a low level of coal charge stockline, which makes possible to linger the coke gas in the underroof space and to overheat with increasing the access of light fractions of the resin with the gas.

Evaluation of Antifungal and Antioxidant Effects of Qutran (Wood Tar) from Olea europaea Subsp. Cuspidate

Qutran oil (Olea europaea) extracted as medicinal plants extracted has a great activity against four fungistrains. Aspergillus (flavus, fumigatus, niger) and Candida albicans throughout using agar well diffusion in our investgation. Results showed that, tar oilhas antifungal effects against studied strains. Inhibition growth rate was from 16.33 to 46.00 mm. and also has positive activities against investagated organisms more than traditional antibiotics either amphoteracin B or Nystatin. A. fumigatus was mainly susceptible fungi followed by A. niger while A. flavus has the most resistant fungi with inhibition zone (16.33 mm). Wood tar oil, Olea europaea, given a high DPPH radical scavenging activity 79.10% compared to ascorbic acid.

Evaluation of Antibacterial Activity of Pine Tar on Periodontal Pathogenic Bacteria: An In Vitro Study

BACKGROUND: Periodontal pathogens play an important role in etiology and pathogenesis of periodontitis. Microbiological examination of sub gingival plaque is used at the present time in etiological research as well as in clinical treatment of periodontitis to select the appropriate antibiotic agent if indicated. Pine tar has been used for the treatment of various skin diseases. So the study was done to evaluate the effect of Pine Tar oil on bacteria isolated from periodontitis patients.METHODS: Plaque samples from volunteer patients were collected using sterile paper points. Robertson's Cooked Meat (RCM) medium was used for the transportation and cultivation of aerobic, microaerophilic, and anaerobic microorganisms.RESULTS: The result suggests the use of Pine tar oil for topical application in periodontal diseases. Disc diffusion analysis was sufficient enough to illustrate that 75 μl tar oil solution produced growth inhibition of microbial strains.CONCLUSION: Pine tar oil has become one of the important areas of research both in pharmaceutical and periodontal research, hence in vivo studies has to be carried out with various form of pine tar.