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This study focuses on the conversion of biosolids to biochar and its further use in adsorbing per- and polyfluoroalkyl substances (PFASs) from contaminated water. In particular, this study aims to (a) investigate the performance of a semi-pilot fluidised bed pyrolysis unit in converting biosolids into biochar, (b) examine the ability of the pyrolysis–combustion integrated process to destruct PFASs present in biosolids and (c) study the application of biosolids derived biochar for removing PFASs from contaminated water. The semi-pilot fluidised bed pyrolysis unit demonstrated stable temperature and oxygen profiles in the reactor. The yield of biochar was found to be 36–45% at studied temperatures (500–600 °C). The produced biosolids derived biochar samples, due to their lower H/C and O/C ratio, were found to be extremely stable with an expected long (millennia) residence time in soil. It was concluded that >90% removal of perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA) from biosolids derived biochar could be achieved in the pyrolysis–combustion integrated process. The biosolids derived biochar demonstrated >80% adsorption of long-chain PFASs and 19–27% adsorption of short-chain PFASs from PFAS contaminated water.

The experimental solubility data of l-glutamic acid in pure water, formic acid, methanol, 1-propanol, 2-propanol, acetonitrile, and binary mixtures (formic acid + water, methanol + water, 2-propanol + water, acetonitrile + water) with different compositions were carried out at temperatures ranging from (283.15 to 328.15) K by the static analytic method. The solubility measurements showed that formic acid and its aqueous mixtures recorded a higher solubility than methanol + water, 2-propanol + water, and acetonitrile + water for the same composition at each temperature. Moreover, except formic acid the addition of methanol, 2-propanol, and acetonitrile to its aqueous mixtures resulted in the decrease in solubility of l-glutamic acid. The experimental data was fitted using different thermodynamic models such as the Buchowski–Ksiazczak equation, the Van’t Hoff equation, the modified Apelblat equation, and the NRTL model, and the optimum values of the regressed parameters were obtained. The modified Apelblat equation, Buchowski–Ksiazczak equation, and NRTL activity coefficient model were fitted to the pure solvents solubility data, while the modified Apelblat, modified Apelblat–Jouyban–Acree, and NRTL models were used for the binary solvent systems. The results demonstrated formic acid as a cosolvent in the dissolution of l-glutamic acid in formic acid + water binary mixtures, while others exhibited an antisolvent effect on the solubilization of l-glutamic acid in their respective aqueous mixtures.

This paper describes an alternative process for chloroform decomposition via nonthermal plasma polymerization at atmospheric pressure and investigates the effect of methane and hydrogen addition on the process. The effect of both additives was assessed separately, where experiments were conducted in a double dielectric barrier discharge reactor under nonoxidative conditions. The most profound impact of the additives was a significant increase in the yield of non-cross-linked polymer produced compared to that in their absence. The addition of methane resulted in a 120% increase in polymer yield, while in hydrogen the increase was 31%. Critical parameters such as effect of the methane and hydrogen concentration on the conversion of chloroform at various applied voltages, the product distribution, mass balance, and polymer characterization are elucidated in this paper. Single pass conversions of 61% and 68% (with corresponding mass balances of 98% and 95%, respectively) were achieved for CHCl3+ CH4and CHCl3+ H2feed scenarios, respectively. Furthermore, a polymerization mechanism which explains the formation of major chain structures as well as structural defects in the polymer is expounded upon in the paper.

The purpose of this work was to investigate the fitness of the existing truck seats for Bangladeshi truck drivers and suggest a guideline for drivers’ seats based on their anthropometry. In this study, eight anthropometric measurements of 120 Bangladeshi truck drivers and seven seat dimensions of ninety trucks of three brands namely, TATA, ASHOK LEYLAND, and ISUZU were considered for investigating the considerable mismatch between seat dimensions and drivers’ anthropometry. The data were analyzed using two‐sample t‐tests to identify the relationship between existing seat dimensions and drivers’ anthropometry. The results showed a mismatch in seat dimensions and anthropometric measurements for nearly all truck brands and the existing seat dimensions were found to be inappropriate for Bangladeshi drivers. For all the truck brands, the percentage mismatch of seat height, seat depth, seat width, backrest height, and steering wheel clearance varied between 71% and 98%, 23% and 79%, 33% and 84%, 28% and 65%, and 53% and 100% respectively. Subsequently, an attempt was made to provide ergonomically correct seat dimensions for Bangladeshi truck drivers. Further, generalized equations to design the appropriate seat dimensions were developed using the least square regression technique. The recommended seat height, depth and width, backrest height, and steering wheel clearance were found to be appropriate for 82%, 79%, 76%, 98%, and 100% of drivers respectively. The analysis and results of this study can be useful in developing guidelines for design and manufacture of truck driver seats in Bangladesh.

Wastewater treatment facilities typically transform nitrogen compounds into innocuous nitrogen. Phosphorous is partially recovered in biosolids while the potassium cycle in the treatment process is still not well mapped. This paper provides a mapping of the nutrients from household sources (urine, faeces and greywater) to wastewater in the traditional wastewater treatment plants. Following this mapping, the article critically reviews the nutrients recovery technologies, including their applicability at source (for urine) and centralised (for wastewater) levels, benchmarking, social acceptance, and techno-commercial assessments. Additionally, the paper has identified the current technological challenges and opportunities as well as suggested a several future recommendations for developing commercially viable nutrient recovery technologies from urine at source level and wastewater at wastewater treatment plants (centralised level). The high energy requirement, high cost and safety issues are some of the common challenges for most of the nutrient recovery technologies. However, anaerobic membrane bioreactor integrated with biochar or zeolite (for wastewater) and biosorption (for both urine and wastewater) can be highly attractive from those perspectives.

Production of high value biochemicals from lignocellulose biomass via pyrolysis, particularly levoglucosan (LG) has received immense attention in recent years. LG production via fast pyrolysis has recorded a continuous development over the past years, which demands a state-of-the-art review, covering the LG recovery methods and commercial feasibility analysis of the process. This paper provides an in-depth review of the progress and current status of bio-LG production with a focus on formation mechanisms, influential variables, recovery methods and techno-economic prospects. Based on the experimental findings of the previous studies, this review concluded that the LG yield from biomass via pyrolysis could be proposed as a function of biomass structural properties, cellulose content, inorganic minerals content as well as pyrolysis process conditions. An essential aspect of maximising the overall efficiency of LG production process is the adoption of efficient in-situ or post-pyrolysis LG extraction techniques, which has been critically reviewed for the first time. The paper also summarises the techno-commercial assessment studies of LG facility, highlighting the limiting factors towards the economic attractiveness of the process. Finally, the review highlights the knowledge gaps and provides future recommendations, which will be helpful for the improvement of productivity and economic feasibility of bio-LG production process.

This article provides a comparative study of advanced single pot microwave versus conventional solvothermal co-precipitation synthesis for producing magnetic carbon nanocomposites and bio-oil from rice husk. The aim was to produce nanocomposites composed of magnetic nanoparticles and novel graphene on the surface of hydrochar improving the reaction efficiency. The experiments were conducted at two different temperatures (140 °C and 180 °C). The processing time was varied from 0.5 to 2 h. The main focus of the study was to investigate the effect of process parameters on the yield, thermal stability and morphology. Microwave-assisted solvothermal carbonisation (MSTC) provided a higher yield of bio-oil compared to solvothermal carbonisation (STC) due to more effective heat transfer to the core of the material. Microwave processing also resulted in less CC and C–H vibrations as measured by FTIR. Transmission electron microscopy confirmed the presence of well-dispersed nanoparticles, ranging in size from 5 to 20 nm in both MSTC and STC. Thermal stability of the nanocomposite materials was significantly higher for conventional solvothermal synthesis compared to the microwave system.