Biological Recovery Research Articles

Bioleaching of Printed Circuit Board Waste to Obtain Metallic Nanoparticles

In this work, a biological recovery of metals (copper and gold) from computer printed circuit board (PCB) waste was carried out by bioleaching using Aspergillus niger. Three bioleaching methods comprising one or two steps or using spent medium were tested in an incubator shaker at 30 °C and 160 rpm with different PCB waste concentrations (2.5 to 10 g/L). Glucose was used as the carbon source. The best condition evaluated was carried out in a stirred tank reactor. The FTIR spectrum confirmed the presence of oxalic, citric, and gluconic acids. A. niger showed an efficiency of bioleaching of up to 100% and 42.5% for copper and gold, respectively, using the two-step method with 2.5 g/L PCB waste after 14 days of the process. The efficiency of bioleaching in a stirred tank reactor was 83% for copper and 24% for gold. The mean metallic particle size obtained after bioleaching varied according to the PCB waste concentration (2.5–10 g/L) added in the experiments. A transmission electron microscope analysis confirmed the synthesis of metallic nanoparticles with spherical morphology. The results indicated that the PCBs bioleaching process with A. niger can be an environmentally friendly alternative to current mechanical and metallurgical processes for metal leaching.

A new approach to biotransformation and value of kitchen waste oil driven by gut microorganisms in Hermetia illucens

Hermetia illucens larvae are known for their ability to recycle organic waste, but their capacity to recover waste oils and the role of gut microorganisms in this process are not fully understood. To gain further insights, the biological recovery of waste frying oil into valuable lipids and the influence of gut bacteria on this biotransformation were investigated. The larvae efficiently digested and absorbed waste frying oil, demonstrating their potential for converting various oils into insect fat. The presence of different fatty acids in their diet significantly altered gut bacterial communities, enriching certain genera such as Actinomyces, Enterococcus, and Providencia. Redundancy analysis revealed that the composition and structure of these bacterial communities were predictive of their function in the biotransformation of fatty acids and the lipid biosynthesis in the larvae. Specific bacteria, including Corynebacterium_1, Providencia, Actinomyces, Escherichia-Shigella, and others, were identified to play specialized roles in the digestion and absorption of fatty acids, contributing to lipid synthesis and storage. These findings highlight the potential of Hermetia illucens in the biological recovery of waste frying oil and underscore the crucial role of gut microbiota in this process, offering a sustainable approach to waste management and bioenergy production.

Responses of SNEDPR-AGS system under long-term exposure of polyethylene terephthalate microplastics for treating low C/N wastewater: Granular effect and microbial structure

The removal of nutrients in sewage treatment plants can be significantly impacted by carbon limitations, especially for treating low carbon to nitrogen ratio (C/N) wastewater, which can markedly increase operational costs. Simultaneous nitrification, endogenous denitrification, and phosphorus removal combined with aerobic granular sludge (SNEDPR-AGS) has emerged as one of the optimal processes for treating low C/N wastewater owing to its high carbon utilization efficiency; however, the long-term effect of microplastics (MPs) on this system remains unclear. This study investigated the granular effect and microbial response of an SNEDPR-AGS system for treating low C/N wastewater under long-term exposure (180 d) to polyethylene terephthalate microplastics (PET-MPs). The results showed that the integrity of the AGS structure was disrupted significantly as the PET-MP concentration increased, with clear AGS cracks appearing on days 180, 124, and 74 after exposure to 1, 10, and 100 mg/L of PET-MPs, respectively. Additionally, the addition of PET-MPs also inhibited denitrification and phosphorus removal due to a decrease in the relative abundance of functional genes (napAB, nirK/nirS, ppk1, ppk2, and ppx). Notably, both chemometric and high-throughput sequencing results indicated that the metabolic form of the system would shift from a polyphosphate-accumulating metabolism to a glycogen-accumulating metabolism. The reason may be that PET-MP stress inhibited the relative abundance of functional genes related to carbon, glycogen, phosphorus, and energy metabolism pathways in Candidatus Accumulibacter and Dechloromonas, but promoted their relative abundance of Candidatus Competibacter. Flow cytometry and molecular docking simulations have also demonstrated the direct toxic effects of PET-MPs on the SNEDPR-AGS system. The biological enhancement and functional recovery of damaged SNEDPR-AGS systems must be further investigated in future studies.

Agronomic potential of different fermented organic composts based on agro-industrial plant waste.

Organic composts such as "bokashi", obtained from the fermentation of bran mixtures and inoculated with microorganisms, improve soil characteristics. In Brazil, the most widely used formulation for the production of this compost is obtained from a mixture of wheat and castor bean bran, but both have a high monetary cost. Replacing these components with regionally available sources represents the possibility of reducing costs and making more sustainable use of this waste. The aim of this study was to analyze the chemical characteristics and determine the availability of nitrogen for the plants. The study was divided into two stages, consisting of an incubation test in the laboratory and a bioassay in the greenhouse using forage sorghum as an indicator species. In the laboratory trial, the treatments consisted of two raw material sources with a low C/N ratio (castor bean bran-CAB and cottonseed bran-COB), corresponding to 40% of the mixture; three sources with a high C/N ratio (wheat bran-WHB or rice bran-RIB), gradually replaced by passion fruit peel bran-PFPB), corresponding to 60% of the mixture. The materials were mixed, moistened, inoculated with microorganisms (Embiotic®) and kept in sealed containers with a capacity of 620 cm3 for 21days. In the greenhouse, in addition to the aforementioned treatments, seven controls were included: no addition of organic and synthetic N sources; ammonium nitrate; CAB; COB; WHB; RIB and PFPB. In the second stage, dry mass production and N content in sorghum plant tissues were determined, and the rates of N availability were estimated. It was found that the pH of the standard compost was 4.75, and in the other formulations it ranged from 4.62 to 5.3, the highest values being observed when WHB was fully replaced by RIB There was a significant difference in the EC values, but all were well below the value considered adequate. Replacing CAB with COB and WHB with RIB and PFPB resulted in a reduction in N content and an increase in the C:N ratio. Replacing WHB with PFPB led to an increase in K content and a reduction in P and Mg content. In the bioassay, the highest biomass production was in the treatments with the fermented composts, and the highest biological recovery of N was obtained in the ammonium nitrate treatment, followed by the CAB, COB and WHB treatments.

The influence of physical rehabilitation on the endocrine function of ovaries of women after oophorectomy

Purpose: The purpose of the work is to analyze the effectiveness of the influence of the developed physical rehabilitation program for women after gynecological surgery, based on the results of the endocrine profile of the main ovarian hormones that have the most pronounced biological effect. Material and methods: 21 women aged 25-34 years were examined after gynecological surgery for ovarian cysts - oophorectomy. They were divided into the control group (n=9) and the main group (n=12). Patients of the main group were engaged in a developed physical rehabilitation program, including shallow breathing with elements of muscle relaxation and auto-training and dosed walking in combination with therapeutic massage to prevent exacerbation or worsening of concomitant diseases. A comparative assessment of changes in the secretion of sex hormones was carried out in dynamics, where indicators of their level after radical treatment in this situation acquire the significance of a test for biological recovery. Results: Analysis of the content of estradiol in the blood shows that in women of both groups during the first and second months after surgery, the remaining ovary functions in an economical mode of the anovulatory menstrual cycle without significant differences between samples within and between groups (p > 0,3). At the third menstrual cycle, only in the main group a clear increase in estradiol appeared (the difference with the first sample is significant, p < 0.05). A faster normalization of the endocrine profile in women of the main group is also confirmed by the data obtained from determining progesterone levels. Its minimum values were recorded during the first two cycles in both groups. The third cycle in women of the main group already reveals progesterone levels in the second phase, corresponding to physiological indicators (р < 0,01). Conclusions. Significantly better differences were revealed between women of the main and control groups according to the results of the endocrine parameters studied, which confirms the effectiveness of the proposed physical rehabilitation program in contrast to the standard system of rehabilitation treatment.

The effect of music on stress recovery

ObjectivePrevious research has suggested beneficial effects of music in reducing stress levels. However, there is no consistent conclusion demonstrating that music can contribute to stress recovery, primarily due to limitations in stress measurement, and inconsistent methodology within existing studies. Our study explores whether relaxing music, especially when self-selected, outperforms non-music acoustic, and silence conditions, fostering both subjective and biological stress recovery. MethodsOne hundred and five healthy female participants underwent the Trier Social Stress Test (TSST) before being randomly allocated to one of four conditions: condition 1 (n = 25) listened to researcher-selected relaxing music; condition 2 (n = 27) listened to self-selected relaxing music; condition 3 (n = 26) listened to the sound of rippling water; and condition 4 (n = 27) remained in silence. Stress parameters were repeatedly measured nine times before and after the TSST. Saliva samples were collected for cortisol and saliva alpha-amylase (sAA) analysis, Movisens equipment was used to measure heart rate (HR) and skin conductance levels (SCL), and Visual Analogue Scales (VAS) were used for subjective stress measurement. ResultsThe examination of SCL, and VAS scores revealed no significant changes following the four relaxation interventions. Although sAA displayed a significant main effect of condition, post hoc tests did not pinpoint specific differences. HR recovery patterns varied among the four relaxation interventions, with the sound of rippling water condition exhibiting a later significant decrease compared to the other conditions. Exploratory analyses revealed that cortisol levels continued increase in all conditions during intervention phase except the researcher-selected music condition. ConclusionsThe subjective and biological stress markers did not exhibit better recovery after the music stimulus, except for a tendency in the researcher-selected music condition to mitigate the continued increase in cortisol levels after the stress test. Our study provides the first evidence comparing the impact of researcher- and participant-selected music with silence and a non-music acoustic stimulus, on both subjective and biological stress recovery. Our findings contribute to a more nuanced understanding of the impact of music on stress recovery.

Potential drivers of changing ecological conditions in English and Welsh rivers since 1990

River invertebrate communities across Europe have been changing in response to variations in water quality over recent decades, but the underlying drivers are difficult to identify because of the complex stressors and environmental heterogeneity involved. Here, using data from ∼4000 locations across England and Wales, collected over 29 years, we use three approaches to help resolve the drivers of spatiotemporal variation in the face of this complexity: i) mapping changes in invertebrate richness and community composition; ii) structural equation modelling (SEM) to distinguish land cover, water quality and climatic influences; and iii) geographically weighted regression (GWR) to identify how the apparent relationships between invertebrate communities and abiotic variables change across the area. Mapping confirmed widespread increases in richness and the proportion of pollution-sensitive taxa across much of England and Wales. It also revealed regions where pollution-sensitive taxa or overall richness declined, the former primarily in the uplands. SEMs confirmed strong increases in average biochemical oxygen demand and nutrient concentrations related to urban and agricultural land cover, but only a minority of land cover's effect upon invertebrate communities was explained by average water chemistry, highlighting potential factors such as episodic extremes or emerging contaminants. GWR identified strong geographical variation in estimated relationships between macroinvertebrate communities and environmental variables, with evidence that the estimated negative impacts of nutrients and water temperature were increasing through time. Overall the results are consistent with widespread biological recovery of Britain's rivers from past gross organic pollution, whilst highlighting declines in some of the most diverse and least impacted streams. Modelling points to a complex and changing set of drivers, highlighting the multifaceted impacts of catchment land cover and the evolving role of different stressors, with the relationship to gross organic pollution weakening, whilst estimated nutrient and warming effects strengthened.

The Development of Environmental Friendly Biological Sulfur Recovery Unit (BSRU) For Sulfur Coated Urea with Slow Release Fertilizer Method: A Case Study in Field X

The absorption of nitrogen from urea fertilizer is significantly inefficient. Due to its solubility in water. This problem can be overcome by producing slow-release fertilizer (SRF) that inhibits urea from being dissolved in water. Sulfur-coated urea (SCU) is one of the SRF methods. Therefore, this study aimed sulfur-coated slow-release urea fertilizer using sulfur waste from the Biological Sulfur Recovery Unit (BSRU) in Field X. A total of 14 tons of sulfur cake was produced daily by BSRU in Field X and sent to the laboratory for composition analysis, followed by drying. Subsequently, the dried sulfur was into a powder using a hammer and sieved to achieve a size of 200 mesh. Based on the results, SCU with the sulfur to urea ratio of 1:1 and mixing time of 15 minutes exhibited the best performance in dissolution tests with the longest dissolution time of 5 minutes which was better compared to the uncoated urea. After 7 days of observation, spinach that received SCU was more fertile and greener. The calculated NPV and payout time were 88712 million IDR and 1.76 years, respectively. This indicated that the development of this study was economically attractive. In conclusion, the value of sulfur waste from gas processing was increased by using sulfur waste from BSRU as a coating of urea while reducing related environmental effects.

Experimental study of biological wastewater recovery using microbial fuel cell and application of reliability and machine learning to predict the system behavior

Today, the water crisis has necessitated wastewater recovery management more than ever. With the advancement of technology and the emergence of microbial fuel cells (MFCs), wastewater treatment has become an exceptional opportunity for electricity production. In the present work, an experimental study has been carried out for the possibility of treating the wastewater of Borujerd textile factories in a period of ten days using an MFC. In order to save time and costs for experimental studies, the reliability analysis has been used to predict the behavior of fuel cells made in simple mode and multi-anode shared cathode mode. In addition, in order to evaluate the performance of MFCs that are made at the experimental level, deep learning has been used to extract comprehensive relationships. Finally, the economic and environmental evaluation of the simple and multi-anode shared cathode MFC has been done. The research results show that the COD removal efficiency in the system constructed for textile wastewater is 73 %, while the constructed fuel cell maximum power density is 281.5 mW/m2 from wastewater recycling. Reliability analysis of the studied system shows that adding anode to the MFC increases its operational life so for a fuel cell with 6-anodes, the life of the fuel cell increases by approximately 74 days. But in the design of an MFC, it is necessary to pay attention to the cost and emission of environmental pollutants, because the increase of the anode increases the costs and emission of environmental pollutants so that the built fuel cell will function in the most optimal way possible.

Intensive Microalgal Cultivation and Tertiary Phosphorus Recovery from Wastewaters via the EcoRecover Process.

Mixed community microalgal wastewater treatment technologies have the potential to advance the limits of technology for biological nutrient recovery while producing a renewable carbon feedstock, but a deeper understanding of their performance is required for system optimization and control. In this study, we characterized the performance of a 568 m3·day-1 Clearas EcoRecover system for tertiary phosphorus removal (and recovery as biomass) at an operating water resource recovery facility (WRRF). The process consists of a (dark) mix tank, photobioreactors (PBRs), and a membrane tank with ultrafiltration membranes for the separation of hydraulic and solids residence times. Through continuous online monitoring, long-term on-site monitoring, and on-site batch experiments, we demonstrate (i) the importance of carbohydrate storage in PBRs to support phosphorus uptake under dark conditions in the mix tank and (ii) the potential for polyphosphate accumulation in the mixed algal communities. Over a 3-month winter period with limited outside influences (e.g., no major upstream process changes), the effluent total phosphorus (TP) concentration was 0.03 ± 0.03 mg-P·L-1 (0.01 ± 0.02 mg-P·L-1 orthophosphate). Core microbial community taxa included Chlorella spp., Scenedesmus spp., and Monoraphidium spp., and key indicators of stable performance included near-neutral pH, sufficient alkalinity, and a diel rhythm in dissolved oxygen.

Picochloropsis malayensis gen. et sp. nov. (Chlorellales, Chlorophyta), an ammonium tolerant, polyphosphate‐accumulating microalga from seawater

SUMMARYThe significant concentrations of phosphate in wastewater can be considered as an important fertilizer source. Some microalgae uptake phosphate from wastewater and store it in the form of polyphosphate (polyP). Therefore, biological phosphorus recovery processes have been attracting significant attention recently. However, wastewaters are often rich in ammonium, and so microalgae used for phosphorus recovery should be tolerant of this component. In the present study, 151 microalgae were isolated from freshwater, brackish water and seawater. Among them, 11 strains showed higher growth rates in ammonium‐rich media. Of these, the strain SLG4‐06 originating from a marine environment showed the highest polyP accumulation rate and was selected as the most potential alga for phosphorus recovery from wastewater. Based on the morphological and ultrastructural characteristics and phylogenetic analyses of nuclear‐encoded 18S rDNA and chloroplast‐encoded rbcL of strain SLG4‐06, we propose Picochloropsis malayensis gen. et sp. nov. for this strain in the Chlorellales, Trebouxiophyceae. Because P. malayensis can grow in both seawater and freshwater environments, it may be suitable for wastewater treatment in marine aquaculture ponds with widely fluctuating salinity levels.

Temporal Dynamics and Contribution of Phage Community to the Prevalence of Antibiotic Resistance Genes in a Full-Scale Sludge Anaerobic Digestion Plant.

Anaerobic digestion (AD) is an important biological resource recovery process, where microorganisms play key roles for material transformation. There has been some knowledge about the prokaryotic community and antibiotic resistance genes (ARGs) in AD, but there has been very limited knowledge of phages. In this study, samples from a full-scale AD plant were collected over 13 months, sequenced, and analyzed for viral and prokaryotic metagenomes. Totally, 3015 viral operational taxonomic units (vOTUs) were detected, mostly assigned to Caudoviricetes. The phage community had faster temporal variation than the prokaryotic community. Warm seasons harbored a higher abundance of both temperate phages and broad host-range phages. Seven ARGs of 6 subtypes were carried by 20 vOTUs, a representative ermT gene was synthesized and expressed, and the resistance activity in the host was examined, confirming the real activity of virus-carried ARGs in the AD process. Some of the ARGs were horizontally transferred between the phage and prokaryotic genomes. However, phage infection was not found to contribute to ARG transfer. This study provided an insight into the ecological patterns of the phage community, confirmed the antibiotic resistance activity of virus-carried ARGs, evaluated the contribution of phages on the ARG prevalence, and laid the foundation for the control strategies of the community and antibiotic resistance in the AD process.

Unleashing the power of clustering: a qualitative study of cluster organizations’ role in advancing green transformation

PurposeThe purpose of this study is to ascertain how cluster organisations have been fostering green transformation in Poland.Design/methodology/approachThis paper adopts a multiple case study approach. Data collection methods involved in-depth interviews with cluster organisation managers and researchers to identify support measures for green transformation and to investigate the factors influencing their actions as well as a comprehensive analysis of documents, including cluster organisations‘ strategies.FindingsCluster organisations manage and participate in actions that create favourable conditions for pursuing low-carbon and circular economy ventures. They not only assist their members in overcoming obstacles related to green transformation but also engage non-members – which can lead to spillovers reaching beyond their borders. Their engagement takes place across all phases of the green transformation process.Research limitations/implicationsFor various reasons, the research was designed as qualitative to understand the opinions and experiences of various actors engaged in green transformation within cluster organisations’ ecosystems. The key factor influencing this decision stems from the fact that knowledge of the involvement of cluster organisations in supporting green transformation still needs to be completed and scattered. The limitations of the study include limited access to information and the fact that qualitative research allows for a certain amount of subjectivity, and the results should be generalised carefully. Moreover, the interviews were carried out with a non-random sample of participants. Another limitation of the study is related to biased views, which could have been shared by interviewees acting as representatives of the studied cluster organisations.Practical implicationsCluster organisations have emerged as drivers of circular transition by promoting sustainable practices such as material recycling, biological recovery and parts harvesting. These initiatives contribute to reducing waste, conserving resources, and minimising the environmental footprint of industries. These organisations can be active agents of transformation, orchestrating collaborative efforts that have a far-reaching impact on industries and economies.Originality/valueThis is one of the first and most comprehensive studies on the role of cluster organisations in Poland in supporting green transformation. This paper identifies and systematises the actions undertaken to provide a clear understanding of the internal processes within cluster organisations.

Bone and Skin/Subcutaneous Tissue Concentrations of Cefiderocol During Treatment of Extensively Drug-Resistant Pseudomonas aeruginosa.

Pyoderma gangrenosum is a rare dermatologic disorder that disrupts the skin barrier, requiring immunosuppressive therapy. We successfully used cefiderocol for the treatment of an extensively drug-resistant Pseudomonas aeruginosa bacteremia, and presumed osteomyelitis in a patient with severe pyoderma gangrenosum and associated immunosuppressive therapy while being medically optimized for skin grafting. We obtained bone and skin/subcutaneous tissue while the patient was on cefiderocol under an institutional review board-approved biologic waste recovery protocol. Cefiderocol concentrations in bone and skin/subcutaneous tissue were 13.9 and 35.9 mcg/g, respectively. The patient recovered from bacteremia and underwent autografting without further complications. Cefiderocol at approved dosing of 2 g IV (3-hour infusion) every 8 hours resulted in bone and skin/subcutaneous tissue concentrations adequate to treat extensively drug-resistant Gram-negative bacteria that remain susceptible to cefiderocol.

Puget Sound sediment cleanup remedy effectiveness retrospective.

The monitoring of completed large-scale sediment remediation projects has revealed mixed effectiveness at reducing risks, thus highlighting uncertainties regarding whether and which remedial measures are necessary to achieve protective goals. To support valid statements about changes over time and the overall effectiveness of sediment remedial action, robust pre- and postremediation monitoring is required with sufficient time points, reference sites, and biological metrics. The five completed Puget Sound sediment remediation case studies reviewed here (Bellingham Bay, St. Paul Waterway, Eagle Harbor, Hylebos Waterway, and Sinclair Inlet) employed particularly robust remedy effectiveness monitoring programs that spanned decades, revealing common lessons for improving remediation outcomes. First, although sediment remediation can play an important role in reducing contaminant exposure in areas with higher sediment concentrations, at lower levels, sediment links with fish tissue concentrations diminish. As water column exposure from diverse sources becomes predominant, remediating sediments with lower concentrations yields proportionately less risk reduction. Second, timely monitoring of effective source controls achieving substantial (i.e., >80%) contaminant source load reductions as well as large-scale capping projects have revealed rapid changes in Puget Sound surface sediment concentrations and biological recovery metrics with an average recovery half-time of 1.6 ± 0.8 years. The weight of evidence suggests that natural recovery of Puget Sound surface sediments is significantly accelerated by exchange across the sediment-water interface from benthic organism feeding behaviors, porewater flux, and tide-generated currents. As a result, effective source controls in Puget Sound have rapidly improved surface sediment quality and achieved more significant risk reductions than broadscale sediment remediation. Going forward, comprehensive Puget Sound source control efforts that incorporate robust monitoring in an adaptive management framework are the best way to achieve protective remediation objectives. These lessons may apply more broadly across similar complex urban aquatic ecosystems. Integr Environ Assess Manag 2024;20:1355-1365. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Interrelationships among Early Triassic faunas of Western Gondwana and Laurasia as illuminated by a new South American benthosuchid temnospondyl.

The End-Permian Mass Extinction marked a critical turning point in Earth's history, and the biological recovery that followed the crisis led to the emergence of several modern vertebrate and invertebrate taxa. Even considering the importance of the Early Triassic biotic recovery for the evolution of modern faunas and floras, our knowledge of this event is still hindered by the sparse sampling of crucial geological formations. This leaves our understanding of Early Triassic ecosystems fundamentally biased toward productive and historically well-explored geological units. Recent surveys in poorly known Gondwanan localities, such as those within the Sanga do Cabral Formation in southern Brazil, have unveiled insights into Early Triassic terrestrial ecosystems, shedding light on a diverse and previously unknown tetrapod fauna. Here, we report the discovery of a new temnospondyl genus and species in the Lower Triassic Sanga do Cabral Formation. The new taxon can be confidently assigned to the Benthosuchidae, a stereospondyl clade with a distribution previously restricted to the East European Platform. Phylogenetic analysis confirms the relationship of the new genus to the trematosaurian lineage, being closely related to the genus Benthosuchus. Our results raise questions about the biogeographical history of stereospondyls after the End-Permian Mass Extinction and suggest a potential connection between Russian and South American Early Triassic faunas. Further investigations are needed to thoroughly explore the potential dispersal routes that may explain this seemingly unusual biogeographical pattern.

Mixing Compost and Biochar Can Enhance the Chemical and Biological Recovery of Soils Contaminated by Potentially Toxic Elements.

Biochar and compost are able to influence the mobility of potentially toxic elements (PTEs) in soil. As such, they can be useful in restoring the functionality of contaminated soils, albeit their effectiveness can vary substantially depending on the chemical and/or the (micro)biological endpoint that is targeted. To better explore the potential of the two amendments in the restoration of PTE-contaminated soils, biochar, compost (separately added at 3% w/w), and their mixtures (1:1, 3:1, and 1:3 biochar-to-compost ratios) were added to contaminated soil (i.e., 2362 mg kg-1 of Sb and 2801 mg kg-1 of Zn). Compost and its mixtures promoted an increase in soil fertility (e.g., total N; extractable P; and exchangeable K, Ca, and Mg), which was not found in the soil treated with biochar alone. All the tested amendments substantially reduced labile Zn in soil, while biochar alone was the most effective in reducing labile Sb in the treated soils (-11% vs. control), followed by compost (-4%) and biochar-compost mixtures (-8%). Compost (especially alone) increased soil biochemical activities (e.g., dehydrogenase, urease, and β-glucosidase), as well as soil respiration and the potential catabolic activity of soil microbial communities, while biochar alone (probably due to its high adsorptive capacity towards nutrients) mostly exhibited an inhibitory effect, which was partially mitigated in soils treated with both amendments. Overall, the biochar-compost combinations had a synergistic effect on both amendments, i.e., reducing PTE mobility and restoring soil biological functionality at the same time. This finding was supported by plant growth trials which showed increased Sb and Zn mineralomass values for rigid ryegrass (Lolium rigidum Gaud.) grown on biochar-compost mixtures, suggesting a potential use of rigid ryegrass in the compost-biochar-assisted phytoremediation of PTE-contaminated soils.

Biological Iron Removal and Recovery from Water and Wastewater.

Iron is a common contaminant in source water and wastewater. The mining and metallurgical industries in particular can produce and discharge large quantities of wastewater with high iron concentrations. Due to the harmful effects of iron on organisms and infrastructure, efficient technologies for iron removal from water and wastewater are needed. On the other hand, iron is a valuable commodity for a wide range of applications. Microorganisms can facilitate iron removal and recovery through aerobic and anaerobic processes. The most commonly utilized microbes include iron oxidizers that facilitate iron precipitation as jarosites, schwertmannite, ferrihydrite, goethite, and scorodite, and sulfate reducers which produce hydrogen sulfide that precipitates iron as sulfides. Biological iron removal has been explored in various suspended cell and biofilm-based bioreactors that can be configured in parallel or series and integrated with precipitation and settling units for an effective flow sheet. This chapter reviews principles for biological iron removal and recovery, the microorganisms involved, reactor types, patents and examples of laboratory- and pilot-scale studies, and full-scale implementations of the technology.

Preventing Unplanned Shutdown due to Injection Well Plugging with After Treatment Unit Integrated Membrane at Matindok CPP

Pertamina EP Pertamina EP Donggi Matindok Field realizes that sustainable development activities need to pay attention to environmental aspects, including efforts to reduce the load of water pollution. In the production process at Matindok Central Processing Plant (CPP), byproducts are produced in 2 forms: solid sulphur and wastewater from the Biological Sulphur Recovery Unit (BSRU). Sulphur solids carried in wastewater can cause blockages known as plugging in injection wells and disrupt the production process. This study aims to reduce the water pollutants by integrating a nanofiltration membrane in the Bleed Water Treatment (BWT) to reduce the Total Dissolved Solid (TDS) content in wastewater after being processed in the After Treatment Unit (ATU). The experimental results showed a significant decrease in TDS values after nanofiltration membrane integration, from ≥14,000 mg/L to <4,000 mg/L. This program succeeded in reducing water pollution in 2023 by 272.68 tons of TDS.

Drivers and resilience of methane-derived carbon contribution to chironomid biomass in boreal lakes

General mechanisms underlying the pathways of methane (CH4)-derived carbon in aquatic food webs are often associated with eutrophication-driven anoxia. Yet, the influence of changing nutrient availability on CH4 cycling has been mainly investigated during the increasing phase (i.e. onset of anthropogenic eutrophication), thus leaving unclear whether nutrient reduction can lead to a simple reversion of the observed effects on CH4 cycling. We combined stable isotopes of chironomid remains (δ13CHC) and sedimentary ancient DNA of methanotrophic bacteria (MOB) to unravel the drivers of biogenic CH4 contribution to chironomid biomass in boreal lakes. Using a spatial dataset, our study shows that δ13CHC values were more depleted in hypoxic lakes and were positively associated with methanotrophic bacteria belonging to the γ-proteobacteria class (MOB type I), therefore supporting the view of higher utilization of CH4-derived carbon in anoxic environments. However, this space-for-time substitution approach failed to provide any reliable information on whether lake food webs follow the same pathway in forward and reverse directions. Using downcore reconstruction, our results show that despite a drastic mitigation-induced decrease in nutrient concentrations and strong evidence of biological recovery of algal and chironomid communities, chironomid biomass remained highly subsidized by methanotrophic bacteria throughout the study period. Results therefore suggest that mechanisms underlying the pathways of CH4-derived carbon in aquatic food webs are likely not the same during perturbation and recovery trajectories and that complex feedback mechanisms can stabilize lakes in this CH4-based food web state.