•HTC of PL was performed from 150°C to 300°C and from 30 to 480min.•Influences of treatment temperature and time on carbonisation were evaluated.•The HHV of produced hydrochar was increased to ...25.17MJ/kg.•The hydrochar properties were highly dependent on treatment temperature.
In this study, hydrochars were prepared by hydrothermal carbonisation (HTC) of poultry litter (PL) at temperatures between 150–300°C with residence times of 30, 120 and 480min. The effects of treatment temperature and residence time on the yield and composition of hydrochar were investigated. Both treatment temperature and residence time effects were observed however, the effect of residence time was lower. The results indicated that the HHV was improved by up to 25.17% and the overall ash in hydrochar was significantly lower compared to PL, however this coincided with a lower hydrochar yield.
•Hydrothermal treatment of PL was performed at varying pH.•pH value was varied using CH3COOH or H2SO4.•Influences of pH on carbonisation were evaluated.•Structures and chemical compositions of ...hydrochars were evaluated.
In this study, hydrothermal carbonisation (HTC) of poultry litter (PL) was carried out to evaluate the impact of initial pH using acetic acid (CH3COOH) or sulfuric acid (H2SO4) on the yields and properties of hydrochar (HC). The PL samples were treated by HTC at various initial pH and at 250°C for 2h. The HCs produced were characterized by ultimate, proximate and fibre analyses as well as heating value and surface area measurements. The results indicated that undertaking HTC in the presence of acids (CH3COOH, H2SO4) significantly affects the yields and properties of HC. The C content and HHV of the HC increased with decreasing initial pH. In the presence of H2SO4, the hydrochar yield (HY) increased while the ash content was significantly reduced. The lowest ash content and the highest HY were measured in the HC produced from the suspension with an initial pH of 2 using H2SO4.
In this study, the effects of operating parameters on the behavior of nutrients during hydrothermal carbonization (HTC) of poultry litter (PL) were investigated. A number of HTC experiments were ...carried out using PL at different treatment temperatures, residence times, and initial pH. The standard measurement and testing protocol was adapted to determine the phosphorus (P) species in the solid hydrochar (HC), while the Ca, K, Mg, Na, Al, Zn, Mn, Fe, Cu, Cr, and Pb contents in each fraction were quantified and related to the P fractions. The results indicate that HTC can effectively reduce the solubility of most of the measured elements. The treatment temperature and initial pH can significantly influence the speciation of P and other nutrients, while the residence time effects were apparent at low treatment temperature. The majority of the measured nutrients remained in the HC when the hydrochar was produced without additional acid. Addition of acids, particularly H2SO4, provides a good approach for nutrient recovery.
Adsorption studies were carried out on a red mud modified sawdust biochar material to assess its capacity in the removal of vanadium (V) from aqueous solution. In this study, a number of parameters ...which can potentially influence V(V) adsorption were investigated including equilibrium V(V) solution concentration, contact time for effective V(V) removal, temperature of the adsorption process, solution pH and ionic strength. The uptake of V(V) was shown to be heavily influenced by solution pH with maximum uptake (16.45 mg g−1) achieved in the pH range of 3.5 - 5.5. The adsorption process was best described by the Langmuir model. The kinetics of the adsorption process indicated that V(V) uptake occurred within 60 min of contact and that pseudo-second order kinetics best described the kinetics of the overall adsorption process. There was a clear increase in V(V) uptake with increasing temperature (range 293–343 K) indicating an endothermic adsorption process and the level of uptake remained largely unchanged at solution salt concentrations of up to 0.1 M NaCl and competing cation concentrations of up to 2000 mg L-1 of sodium and 200 mg L-1 aluminium. The relatively weak interaction between V(V) and the modified biochar surface may indicate a possibility of recovery of the bound V(V) and subsequent regeneration of the adsorbent.
•Hydrothermal carbonization (HTC) of poultry litter to high-value materials.•ANN modelling of HTC process considering reaction temperature and time as inputs.•Improving ANN predications by coupling ...with Kriging interpolation model.•Study on effect of process parameters using the developed model.
Modeling of hydrothermal carbonization (HTC) of poultry litter to high-value materials was conducted in order to understand the process and predict the influence of process parameters on product properties. Reaction temperature and time were considered as inputs, whereas carbon and inorganic phosphorous recovery were considered as responses in the model. Artificial neural network (ANN) model was used in order to correlate the process parameters to the outputs. The model was trained and validated using the data collected from HTC experiments carried out at temperatures between 150 ≤ T ≤ 300 °C, and residence time between 30 ≤ t ≤ 480 min. In order to improve the predictability of ANN, more theoretical data points were generated using Kriging approach based on the available measured data. Kriging interpolation improved the ANN model dramatically in training and validation phases, where the carbon recovery model fitting was improved by 0.94% and 9.2% in training and validation respectively, and the inorganic phosphorous (IP) recovery model fitting was improved by a staggering 16.4% and 19.6% in training and validation respectively. This improvement is also reflecting on the derived profiles of carbon and IP recovery in terms of the process parameters. The validated model was then used to understand the effect of process parameters on the response. It was revealed that temperature has more significant effect on the carbon and phosphorous recovery, while the effect of reaction time is more important at low reaction temperatures. The derived profiles shows a monotonic increase in IP recovery and a monotonic decrease in Carbon recovery at higher temperatures and time, this is due to multiple mechanism occurring simultaneously in the HTC reactor at various temperatures and times.
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•KOH modified Ascophyllum nodosum seaweed hydrochar is an effective V(V) adsorbent;•Weak binding of V(V) to the hydrochar indicates a reversible adsorption process;•The impact of ...co-existing cations had negligible impact on uptake of V(V);•Desorption and re-adsorption results indicate reusable potential for V(V) recovery.
Vanadium exists as a mobile and toxic trace metal in many alkaline residue leachates. Its removal and recovery not only reduces a global environmental risk but is also critical to the emergence of innovative technologies and the circular economy. In parallel, the use of treated biomass feedstock is receiving increased attention as a low cost adsorbent for toxic metals in wastewater. This study investigated the adsorption of Vanadium (V) from aqueous solution by KOH modified seaweed (Ascophyllum nodosum) hydrochar (HCKOH). The results showed that HCKOH is an effective V(V) adsorbent, achieving maximum uptake of 12.3 mg g−1 at solution pH 4, 60 min contact time and temperature 293 K. The kinetics followed a pseudo second order model with film diffusion controlling the overall adsorption rate. The type I adsorption isotherm was well fitted to a Langmuir model (qm = 12.3 mg g-1, R2 = 0.970, RMSE = 0.66) and a thermodynamic study indicated that the V(V) adsorption was both exothermic and spontaneous. The low enthalpy change (-10.97 kJ mol−1) indicated a weak binding of V(V) to HCKOH pointing to the possibility of V recovery. The impact of co-existing cations on V(V) uptake was negligible for Na(I) and Ga (III) but was reduced slightly for Al(III). Desorption and re-adsorption results (3 cycles) indicated that HCKOH has reusable potential to remove and recover V(V) from waste leachates.
Transparency and accountability are the main levers of current public policy. In every public organization, citizens expect accountability, transparency and fairness. This is more intensive when we ...discuss about the Israeli Police which is a public organization that is allowed to activate force and to deprive the freedom of the citizen. Avidar, Sagi & Zuk (2014) argue that effective and efficient policing is the result of many factors. It depends not only on the efficiency of the police or its diligence, but also on the relationships between the police and the community that is serves. The RAND Report (2014) presents a model for efficient and effective policing which is based on procedural justice. The basis for the RAND Model (2014) is that the Israeli Police needs a more efficient strategy in developing and cultivating public support for it. In order to influence public support for the Israeli Police, the Israeli Police should adopt a modern policing model. This is involved in adopting strategies for increasing police transparency, increasing accountability and reducing existing stigmas regarding minorities. This model has been tested and presented in this article.
Increasing evidence points towards an inflammatory component underlying pulmonary hypertension. However, the conclusive characterisation of multiple inflammatory cell populations in the lung is ...challenging due to the complexity of marker specificity and tissue inaccessibility. We used an unbiased computational flow cytometry approach to delineate the inflammatory landscape of idiopathic pulmonary arterial hypertension (IPAH) and healthy donor lungs.Donor and IPAH samples were discriminated clearly using principal component analysis to reduce the multidimensional data obtained from single-cell flow cytometry analysis. In IPAH lungs, the predominant CD45
cell type switched from neutrophils to CD3
T-cells, with increases in CD4
, CD8
and γδT-cell subsets. Additionally, diversely activated classical myeloid-derived dendritic cells (CD14
HLA-DR
CD11c
CD1a
) and nonclassical plasmacytoid dendritic cells (pDCs; CD14
CD11c
CD123
HLA-DR
), together with mast cells and basophils, were more abundant in IPAH samples. We describe, for the first time, the presence and regulation of two cell types in IPAH, γδT-cells and pDCs, which link innate and adaptive immunity.With our high-throughput flow cytometry with multidimensional dataset analysis, we have revealed the interactive interplay between multiple inflammatory cells is a crucial part of their integrative network. The identification of γδT-cells and pDCs in this disease potentially provides a missing link between IPAH, autoimmunity and inflammation.
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