The stability and performance of a two-stage anaerobic membrane process was investigated at different organic loading rates (OLRs) and Hydraulic Retention Times (HRTs) over 200 days. The Hydrolytic ...Reactor (HR) was fed with the Organic Fraction of Municipal Solid Waste (OFMSW), while the leachate from the HR was fed continuously to two Submerged Anaerobic Membrane Bioreactors (SAMBR1 and 2). The Total COD (TCOD) of the leachate varied over a wide range, typically between 4000 and 26,000
mg/L while the Soluble COD (SCOD) in the permeate was in the range 400–600
mg/L, achieving a COD removal greater than 90% at a HRT of 1.6–2.3 days in SAMBR1. The operation was not sustainable below this HRT due to a membrane flux limitation at 0.5–0.8
L/m
2
h (LMH), which was linked to the increasing MLTSS. SCOD in the recycled permeate did not build up indicating a slow degradation of recalcitrants over time. SAMBR2 was run in parallel with SAMBR1 but its permeate was treated aerobically in an Aerobic Membrane Bioreactor (AMBR). The AMBR acted as a COD-polishing and ammonia removal step. About 26% of the recalcitrant SCOD from SAMBR2 could be aerobically degraded in the AMBR. In addition, 97.7 % of the ammonia–nitrogen was converted to nitrate in the AMBR at a maximum nitrogen-loading rate of 0.18
kg NH
4
+–N/m
3
day. GC–MS analysis was performed on the reactor effluents to determine their composition and what compounds were recalcitrant.
1,1-Diamino-2,2-dinitroethene (DADNE, FOX-7) is an explosive of current interest. In our work, an advanced study of detonation characteristics of this explosive was performed. DADNE was prepared and ...recrystallized on a laboratory scale. Some sensitivity and detonation properties of DADNE were determined. The detonation performance was established by measurements of the detonation wave velocity, detonation pressure and calorimetric heat of explosion as well as the accelerating ability. The JWL (Jones–Wilkins–Lee) isentrope and the constant-
γ isentrope for the detonation products of DADNE were also found.
The widespread use of pyrotechnic compositions in time delay detonators is the reason for research aimed at expanding knowledge of the combustion properties of new pyrotechnic mixtures, whose ...components react with each other in the solid or liquid state. Such a method of combustion would make the rate of combustion independent of the pressure inside the detonator. This paper presents the effect of the parameters of W/CuO mixtures on their properties of combustion. As this composition has not been the subject of previous research and is not described in the literature, the basic parameters, such as the burning rate and the heat of combustion, were determined. In order to determine the reaction mechanism, a thermal analysis was performed, and the combustion products were determined using the XRD technique. Depending on the quantitative composition and density of the mixture, the burning rates were between 4.1-6.0 mm/s and the heat of combustion in the range of 475-835 J/g was measured. The gas-free combustion mode of the chosen mixture was proved using DTA and XRD. Determination of the qualitative composition of the combustion products and the heat of combustion allowed estimation of the adiabatic combustion temperature.
► LCA model of starch-PVOH insulated bio-packaging in anaerobic digestion (AD) system. ► Complete LCA inventory: new lab results combined with site-specific data for AD plant. ► With active inocula, ...anaerobic digestibility of starch-PVOH biopolymers achieved 62%. ► AD plus recycling is environmentally superior option for bio-packaging modelled. ► Optimizing the energy utilization system brings environmental benefits to AD process.
The digestibility of a starch–polyvinyl alcohol (PVOH) biopolymer insulated cardboard coolbox was investigated under a defined anaerobic digestion (AD) system with key parameters characterized. Laboratory results were combined with industrial operational data to develop a site-specific life cycle assessment (LCA) model. Inoculated with active bacterial trophic groups, the anaerobic biodegradability of three starch–PVOH biopolymers achieved 58–62%. The LCA modeling showed that the environmental burdens of the starch–PVOH biopolymer packaging under AD conditions on acidification, eutrophication, global warming and photochemical oxidation potential were dominated by atmospheric emissions released from substrate degradation and fuel combustion, whereas energy consumption and infrastructure requirements were the causes of abiotic depletion, ozone depletion and toxic impacts. Nevertheless, for this bio-packaging, AD of the starch–PVOH biopolymer combined with recycling of the cardboard emerged as the environmentally superior option and optimization of the energy utilization system could bring further environmental benefits to the AD process.
Confined and semi-closed explosions of new class of energetic composites as well as TNT and RDX charges were investigated using optical spectroscopy. These composites are considered as thermobarics ...when used in layered charges or enhanced blast explosives when pressed. Two methods to estimate fireball temperature histories of both homogeneous and metallized explosives from the spectroscopic data are also presented, compared and analyzed. Fireball temperature results of the charges detonated in a small explosion chamber under air and argon atmospheres, and detonated in a semi-closed bunker are presented and compared with theoretical ones calculated by a thermochemical code. Important conclusions about the fireball temperatures and the physical and chemical phenomena occurring after the detonation of homogeneous explosives and composite formulations are deduced.
•Optical spectroscopy as a tool to investigated new composite metallized explosives.•For safety purposes experimental procedure must be strictly followed.•.Fireball temperatures are determined using a linear fitting of Wien’s relation.•Fireball temperature histories of new thermobaric composites are measured.
Lacprodan®PL20, a dairy ingredient that is rich in protein and polar lipids, was added into set yoghurts produced from nonhomogenized raw milk. The set yoghurts were prepared using concentrations of ...2%, 4%, and 6% Lacprodan®PL20, while the control sample was only supplemented with skim milk powder. The effect of Lacprodan®PL20 concentrations on the physical and chemical properties, rheology, and microstructure of set yoghurt was thoroughly investigated to determine some likely improvement or changes in quality. Consequently, Lacprodan®PL20 showed a gradual improvement in the set yoghurt nutritive values, water holding capacity, and apparent viscosity. The results indicated that the firmness of set yoghurt was altered which steadily improved the gel strength, especially at 4% and 6% concentrations. The fermentation process was slightly delayed at 4% and 6% concentrations and pH values were raised as Lacprodan®PL20 concentration increased. The microstructures of the set yoghurts produced with Lacprodan®PL20, as examined by scanning electron microscopy, revealed compacted structures with fewer and smaller holes in the gel matrices. Also, a slight color change was observed in set yoghurt using a colorimeter. These results vividly showed that Lacprodan®PL20, an enriched milk fat globule membrane fragment, has the potential to improve set yoghurt quality by reducing some defects associated with set yoghurt, such as low gel strength, low dry solids, and the likes.
A batch of the Organic Fraction of Municipal Solid Waste (OFMSW) was treated in a two-step process with effluent recirculation comprising a novel hydrolytic reactor (HR) followed by a Submerged ...Anaerobic Membrane Bioreactor (SAMBR) operating at a stable permeate flux of 5.6 L/m(2) hr (LMH). A soluble COD removal higher than 95% was obtained from the SAMBR. The soluble COD as well as the Total Suspended Solids (TSS) did not build up due to efficient hydrolysis inside the SAMBR, and no VFA accumulation occurred due to the complete retention of methanogens by the membrane as well as the formation of syntrophic associations. Because of the microfiltration membrane in the second reactor a stabilized leachate was obtained from the very first days of the treatment and the highly stable process enabled shorter treatment periods compared to traditional leach bed processes. This experiment showed that the recycle of the stabilised leachate does not lead to a build up of SCOD. Size exclusion chromatography analysis confirmed that high molecular weight compounds were completely degraded and did not appear in the SAMBR permeate, and that low molecular weight fulvic-like and medium MW material were present in the permeate of the SAMBR but their concentration remained stable with time.
Conceptually new cylindrical charges enveloped by Al foils have been designed and their thermobaric effects, due to simultaneous fragmentation and combustion of the foils, have been experimentally ...determined. The fragmentation processes of Al foil was supported by numerical simulations. It has been shown that the quasistatic pressures (QSP) for phlegmatized RDX (RDXph) enveloped with Al-coated plastic foils are higher than that of the pure RDXph, due to combustion of these foil fragments in a thermobaric explosion. The QSP generated by Al–Ni foils enveloping RDXph was found to be much lower than performance of other foils, possibly due to relatively inert nature of Ni. In a small detonation chamber, the charges of RDXph/Al foil (RDXph/Alf) produced even higher experimental maximum peak pressure (Δpmax) than the charges that contained Al powder (Alp). In a closed bunker, the impulse amplitudes of RDXph enveloped by aluminized polyethylene (Al-PE) foils and RDXph enveloped by 100µm Alf (Alf100) charges are much lower than those of the other charges. It was found that the charges enveloped by Al foils have even larger Δpmax than that of RDXph/Alp charges, indicating that the Alf could generate better blast performances than the Alp. The simulations indicate that the observed blast enhancement is dependent not on the thickness, but on the size of surrounding space. The thermobaric fire-ball generated by 40g RDX/Alf charge could sustain combustion up to 40ms, reaching a maximum radius of about 2.4m.
Abstract In this work, a novel graphite intercalation compound (GIC) particle electrode was used to investigate the adsorption of Reactive Black 5 (RB5) and the electrochemical regeneration in a ...three-dimensional (3D) electrochemical reactor to recover its adsorptive capacity. Various adsorption kinetics and isotherm models were used to characterise the adsorption behaviour of GIC. Several adsorption kinetics were modelled using linearised and non-linearised rate laws to evaluate the viability of the sorption process. Studies on the selective removal of RB5 dyes from binary mixture in solution were evaluated. RSM optimisation studies were integrated with ANOVA analysis to provide insight into the significance of selectivity reversal from the salting effect of textile dye solution on GIC adsorbent. A unique range of adsorption kinetics and isotherms were used to evaluate the adsorption process. Non-linear models best simulated the kinetic data in the order: Elovich > Bangham > Pseudo-second-order > Pseudo-first-order. The Redlich–Peterson isotherm was calculated to have a dye loading capacity of 0.7316 mg/g by non-linear regression analysis. An error function analysis with ERRSQ/SSE of 0.1390 confirmed the accuracy of dye loading capacity predicted by Redlich–Peterson isotherm using non-linear regression analysis. The results showed that Redlich–Peterson and SIPS isotherm models yielded better fitness to experimental data than the Langmuir type. The best dye removal efficiency achieved was ~ 93% using a current density of 45.14 mA/cm 2 , whereas the highest TOC removal efficiency achieved was 67%.
Heats of explosion of non-ideal RDX-based compositions in four various atmospheres (argon, nitrogen, air and argon/oxygen mixture) were measured. Charges of phlegmatized RDX containing 30% of two ...types of aluminium powders, coarse aluminium oxide, or fine lithium fluoride particles were fired in a calorimetric bomb of 5.6 dm
3
in volume. The influence of inert and reactive additives and the atmosphere filling the bomb on the heat outcome was examined. To estimate the degree of afterburning of the detonation products and reactive particles, thermochemical calculations were also performed for the tested explosive compositions.
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