Multi-criteria optimisation of subcritical wet oxidation for sludge treatment.

Subcritical wet oxidation (SWO) is an environmentally-friendly solution for sewage sludge volume reduction. However, little study has comprehensively optimised SWO conditions across various aspects. This study developed a multi-objective model using genetic algorithms (GAs) to optimise SWO conditions, considering sludge deconstruction, emissions, energy balance, and resource recovery.

Phytocannabinoids for the Treatment of Neuropathic Pain: A Scoping Review of Randomised Controlled Trials Published Between 2012 and 2023.

Purpose Of Review: Neuropathic pain (NP) remains a challenge to treat, with 50% of patients experiencing limited efficacy from current treatments. Medicinal cannabis, which contains tetrahydrocannabinol (THC), cannabidiol (CBD) and other minor cannabinoids, is garnering attention as an alternative treatment for NP. This paper reviews the clinical evidence for phytocannabinoid treatment of NP.

A novel strategy for integration of oxidation within advanced thermal hydrolysis of sludge.

Due to its environmental impact, the growing production of sewage sludge is a prime concern for wastewater treatment plants. In this study, advanced thermal hydrolysis, the combination of thermal hydrolysis and oxygen, was examined to enhance biogas production and overcome the disadvantages of thermal hydrolysis, including sludge colour, high energy consumption, and high level of ammonia concentration in the treated sludge. A mixture of 55 % primary sludge and 45 % waste activated sludge was pre-treated using advanced thermal hydrolysis at 100, 115, 130, and 145 °C with a processing time varied from 5 to 30 min and oxygen pressure from 10 to 30 bar before anaerobic digestion.

New insight into thermal hydrolysis of sewage sludge from solubilisation analysis.

Thermal hydrolysis, a sludge pre-treatment process prior to anaerobic digestion, is increasing in popularity in academia and industry due to the potential of biogas production enhancement. However, there is a limited understanding of the solubilisation mechanism, which significantly influences the biogas yield. This study evaluated the influence of flashing, reaction time, and temperature to understand the mechanism.

Combination of marine bioactive compounds and extracts for the prevention and treatment of chronic diseases.

Background: In recent years, marine-based functional foods and combination therapy are receiving greater recognition for their roles in healthy lifestyle applications and are being investigated as viable and effective strategies for disease treatment or prevention.

Aim Of The Review: This review article presents and discusses the relevant scientific publications that have studied the synergistic and additive effects of natural marine bioactive compounds and extract combinations with anti-obesity, anti-inflammatory, antioxidant, and chemopreventive activities in the last two decades. The paper presents the mechanism of action and health benefits of developed combinations and discusses the limitation of the studies.

Hydrothermal deconstruction of single-use personal protective equipment during the COVID-19 pandemic.

To minimise the transmission of the SARS-CoV-2 virus, there has been a substantial increase in the production and usage of synthetic personal protective equipment (PPE) globally. Consequently, single-use PPE have been widely adopted without appropriate regulations for their disposal, leading to extensive environmental contamination worldwide. This study investigates the non-catalytic hydrothermal deconstruction of different PPE items, including isolation gowns, gloves, goggles, face shields, surgical masks, and filtering-facepiece respirators.

Hydrothermal deconstruction of single-use personal protective equipment: process design and economic performance.

Increased demand for single-use personal protective equipment (PPE) during the COVID-19 pandemic has resulted in a marked increase in the amount of PPE waste and associated environmental pollution. Developing efficient and environmentally safe technologies to manage and dispose of this PPE waste stream is imperative. We designed and evaluated a hydrothermal deconstruction technology to reduce PPE waste by up to 99% in weight.

Quantification and composition of pharmaceutical waste in New Zealand.

This study aimed to quantify the amount of pharmaceutical waste produced in New Zealand, and determine the composition of pharmaceutical waste from community pharmacies in Auckland, New Zealand. Pharmaceutical waste collected in New Zealand is increasing, peaking at 542 tonne in 2019. Pharmaceutical waste collected from hospitals and pharmacies in Auckland increased by more than fourfold from 2016 to 2020.

Hydrothermal co-hydrolysis of corncob/sugarcane bagasse/Broussonetia papyrifera blends: Kinetics, thermodynamics and fermentation.

Biorefinery of biomass blends can achieve sustainable development of biofuel production. Herein, three lignocellulosic wastes with significant differences in chemical composition-namely corncob (CC), sugarcane bagasse (SB), and Broussonetia papyrifera (BP)-were selected to investigate their hydrothermal co-hydrolysis kinetics and thermodynamics of different biomass blends. Activation energies of hemicellulose decomposition (Ea, 90.

Mechanisms, status, and challenges of thermal hydrolysis and advanced thermal hydrolysis processes in sewage sludge treatment.

Sewage sludge management has garnered interest in both academia and industry due to the challenges of overpopulation and its potential as a bioenergy source. Thermal hydrolysis is a promising technology for sludge pre-treatment prior to anaerobic digestion to enhance biogas production. However, the technology is facing two main problems; the dark colour of sludge can affect UV disinfection and the formation of methanogenesis inhibitors such as free ammonia and refractory compounds have a significant impact on methane production in anaerobic digestion processes.

Challenges in biodegradation of non-degradable thermoplastic waste: From environmental impact to operational readiness.

Non-degradable plastics such as polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) are among the most generated plastic wastes in municipal and industrial waste streams. The mismanagement of abandoned plastics and toxic plastic additives have threatened marine and land fauna as well as human beings for several decades. The available thermal processes can degrade plastic at pilot- and commercial-scale.

Enhancing biogas production from caribbean pelagic Sargassum utilising hydrothermal pretreatment and anaerobic co-digestion with food waste.

The recurring inundation of beaches in the tropical North Atlantic by pelagic Sargassum and the associated social, ecological and economic challenges, have aroused great interest in its potential use as a marine energy crop. However, to date, the seasonal availability and low experimental methane potential of these invasive brown seaweeds have hindered their commercial exploitation as feedstock for sustainable energy production. This novel study evaluated Caribbean pelagic Sargassum and the synergistic interactions of hydrothermal pretreatment and co-digestion with food waste at different mixture ratios, on biogas production enhancement and bio-fertiliser recovery.

Oxidative hydrothermal surface modification of activated carbon for sevoflurane removal.

The emission of waste anaesthetic gas is a growing contributor to global warming and remains a factor in atmospheric ozone depletion. Volatile anaesthetics in medical waste gases could be removed via adsorption using suitable activated carbon materials possessing an enhanced affinity to anaesthetic molecules. In this work, the effects of surface physical and chemical properties on sevoflurane adsorption were investigated by oxidative hydrothermal surface modification of a commercial activated carbon using only distilled water.

Degradation of plastic waste using stimulated and naturally occurring microbial strains.

The capability of different strains derived from soil, activated sludge, farm sludge, and worms' excreta were investigated for biodegradation of high-density polyethylene, polystyrene foam, polypropylene and polyethylene terephthalate in unstimulated and stimulated conditions. Biodegradation using naturally occurring microbial strains examined in mixed (270 days) and individual (100 days) systems, while HO stimulated strains were tested only in the mixed system (30 days). Penicillium raperi, Aspergillus flavus, Penicillium glaucoroseum and Pseudomonas sp.

Enrichment of surface oxygen functionalities on activated carbon for adsorptive removal of sevoflurane.

Activated carbons have been reported to be useful for adsorptive removal of the volatile anaesthetic sevoflurane from a vapour stream. The surface functionalities on activated carbons could be modified through aqueous oxidation using oxidising solutions to enhance the sevoflurane adsorption. In this study, an attempt to oxidise the surface of a commercial activated carbon to improve its adsorption capacity for sevoflurane was conducted using 6 mol/L nitric acid, 2 mol/L ammonium persulfate, and 30 wt per cent (wt%) of hydrogen peroxide (HO).

Breakthrough analysis of continuous fixed-bed adsorption of sevoflurane using activated carbons.

The inhalational anaesthetic agent - sevoflurane is widely employed for the induction and maintenance of surgical anaesthesia. Sevoflurane possesses a high global warming potential that imposes negative impact to the environment. The only way to resolve the issue is to remove sevoflurane from the medical waste gas before it reaches the atmosphere.

Valorisation of food waste via hydrothermal carbonisation and techno-economic feasibility assessment.

Food waste constitutes a remarkable portion of municipal solid waste. About one-third of the global food waste produced is lost with the food supply chain. Food waste in many countries is still dumped of in landfill or incinerated simultaneously with other municipal wastes.

Effect of temperature on the fuel properties of food waste and coal blend treated under co-hydrothermal carbonization.

A blended feedstock containing food waste and coal was used to perform co-hydrothermal carbonization (Co-HTC) at different temperatures to observe the effect of temperature on the solid fuel properties of different hydrochars. Moreover, these hydrochars were mixed with molasses which act as a binder to prepare high mechanical strength pellets. A range of techniques was used to characterise the hydrochars and pellets.

Rheological characterization of thermal hydrolysed waste activated sludge.

Rheological properties are important in the design and operation of sludge-handling process. Despite this, the rheology of sludge in thermal hydrolysis processes (TH) is not well described. In-situ measurements were performed to characterize the flow behaviour of various concentrations (7-13 wt%) of waste activated sludge (WAS) at TH conditions.

Physicochemical, structural and combustion characterization of food waste hydrochar obtained by hydrothermal carbonization.

A solid carbon-rich product hydrochar, was prepared using hydrothermal carbonisation of food waste at temperatures of 200, 250 and 300 °C. To acquire detailed insight into physicochemical and structural properties, hydrochar samples were characterised using a range of techniques. The carbon content and higher heating value of food waste increased considerably from 39 to 73% and 15 to 31 MJ/kg corresponding to the heating temperature.

Energy performance evaluation of ultrasonic pretreatment of organic solid waste in a pilot-scale digester.

It has been proven that ultrasonic pretreatment (UP) has positive effect on biogas generation from previous lab-scale studies. However, that is not always the case in larger scale processes. The purpose of this study was to evaluate the effectiveness of UP to biogas generation in terms of anaerobic digestion process and energy efficiency.

Effect of hydrodynamic mixing conditions on wet oxidation reactions in a stirred vessel reactor.

The aim of this study was to investigate the impact of mixing intensity and mixing flow patterns on solid waste degradation, and production of valuable intermediate by-products such as acetic acid. Total suspended solids generally decreased, soluble chemical oxygen demand, dissolved organic carbon, and acetic acid concentration generally increased with the progress of the reaction and increase in the mixing intensity. The results showed that axial-radial flow pattern (using pitch blade impeller) and medium impeller speed (500 rpm) resulted in a higher degree of solid degradation and production of acetic acid.

Rheological characterisation of biologically treated and non-treated putrescible food waste.

Food waste is gaining increasing attention worldwide due to growing concerns over its environmental and economic costs. Understanding the rheological behaviour of food waste is critical for effective processing so rheological measurements were carried out for different food waste compositions at 25, 35 and 45 °C. Food waste samples of various origins (carbohydrates, vegetables & fruits, and meat), anaerobically digested and diluted samples were used in this study.

Variation in metals during wet oxidation of sewage sludge.

Sewage sludge is a significant by-product from wastewater treatment plants but is potentially hazardous due to its pathogenic or harmful contents, such as toxic metals. Subcritical water wet oxidation (SCWO) is one method of hydrothermal processing which has recently been used in research and industry for treating sludge. This study investigated the effect of SCWO on metals such as Al, Cu, Fe, and Zn in sludge, including the content of metals in the liquid or solid phase after SCWO and their stability distributions according to Tessier's method.