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In this study, biosorption potential of nine epiphytic bacteria isolated from the rhizosphere of Lepironia articulata and Scirpus grossus were assessed. Identification of the isolated epiphytic rhizobacteria using 16S rRNA analysis showed species belonging to the four genera of Bacillus, Enterobacter, Aeromonas, and Chromobacterium. Batch biosorption studies were carried out to assess the capacity of the isolated bacteria to act as Pb and Cu biosorbents. Different initial concentrations of the two heavy metals (50, 100, 200, 300, and 400 ppm) were used to determine the ability of the biosorbent to reach a tolerance level and then calculate the percentage of biosorption with respect to 0.1 g dry weight. Initial concentration of Pb and Cu exposed showed that the isolated bacteria have high tolerance up to 400 ppm. Bacteria prefer Pb ions over Cu, which is indicated by higher removal of Pb in all tested reactors. Bacillus sp. (coded Sc1) showed the highest biosorption capacity with 100% Pb and 97% Cu removal.

Introduction: Heavy metal pollution has become an important environmental issue today. This study was aimed to identify the heavy metals of the two fishing products namely demersal fish and cephalopods landed at Benoa Port, Bali Province and their health risk effects on consumers. Methods: Demersal fish and cephalopod products were obtained from local fishermen at Benoa port. Atomic Absorption Spectrophotometry (AAS) was used to specify the (Pb, Cd, and Hg) in 34 fish fillet products weighing an average of 500 grams each. Statistical software was used to conduct an analysis of the collected data, while THQ, TTHQ, and TCR were calculated and compared with USEPA regulations. Results and Discussion: The results of this research showed that the content of heavy metals in demersal fish and cephalopod products was lower than the levels suggested by official agencies in a number of countries. In populations of various ages, the target Hazard Quotient (THQ) for the heavy metal was less than 1. At this point, the Total THQ result did not imply any risk to human health from ingestion of these two fishery products. When these two products were ingested, the target cancer risk (TCR) did not represent a cancer risk. Conclusion: The outcomes of this study showed that the bioaccumulation levels of both fishery products with low levels of heavy metals are safe for human consumption.

Acid mine drainage (AMD) is a significant threat to the environment due to its high acidity and metal ion content. To effectively eliminate pollutants from AMD, various approaches are necessary. This review aims to provide a comprehensive understanding of recent advances in AMD mitigation. While treatment technologies have developed to eliminate AMD, they often produce sludge as a by-product and require expensive maintenance. As a cost-effective alternative, the recovery of AMD resources can reduce toxicity and promote reuse of heavy metals and rare earth elements. This review also analyzes the challenges and prospects of AMD mitigation implementation, including current mitigation conditions and knowledge gaps. Researchers can benefit from this review by gaining insight into research progress in this area, identifying strengths and weaknesses of current AMD mitigation applications, and exploring future research directions.

The ability of mixed neem, cassava, and wild betel plant leaves to act as plant-based coagulants was tested in real aquaculture wastewater through the coagulation-flocculation process. The performance of plant-based coagulant (PBC) was compared with that of chemical coagulant (alum) to observe the removal efficiency of turbidity, TSS, color, and COD. Ratio, as a new approach, was used by selecting TSS as an indicator or index to substitute for the dosage term and calculated based on a simplified equation. The extracted medium for these coagulants was prepared by using water extraction. Initial characterizations showed that the PBC had some carbon and amine groups (as also confirmed by LC-MS) with an average zeta potential of –22.83 ± 0.62 mV. Results indicated both coagulants (plant-based and chemical coagulants) successfully removed the measured polluted parameters of turbidity (85.17 %), TSS (80.28 %), color (59.42 %), and COD (54.63 %) for PBC with dosage of 0.79 mg/L and coagulant mass of 3.94 mg, while alum gained a higher removal with turbidity (99.08 %), TSS (98.71 %), color (97.29 %), and COD (75.31 %) with dosage and coagulant mass of 698.4 mg/L and 349.2 mg, respectively. This signaled that alum still acted as the best coagulant, but PBC showed a promising opportunity as a potential substitute for chemical coagulant.

This study aimed to determine the performance of modified slow sand filter (SSF) media with blood clam shells (Anadara granosa) and activated carbon to remove turbidity, TSS, TDS, and FOG on the food court wastewater. The concentration of water pollutant parameters processed by SSF was determined based on Indonesia water quality standards, as well as knowing the optimum operational parameters of intermittent slow sand filter with Response Surface Methodology (RSM). The research data was processed using the Optimal type (custom) design which consisted of independent factors including the type of filter media, the addition of bacteria to the grease trap pre-treatment unit, and running time, as well as the research response in the form of the effectiveness of removing turbidity, TSS, TDS, and FOG. The reactor was operated intermittently (48 hours) for a maximum of 22 days and the concentration of pollutant parameters was calculated using the Standard Methods. The results of the Analysis of Variance (ANOVA, p

The present study investigated the utilization of blood clam shells as a potential substitute for conventional media, as well as the influence of the acclimation time on the efficacy of an intermittent slow sand filter (ISSF) in the treatment of real domestic wastewater. ISSF was operated with 16 h on and 8 h off, focusing on the parameters of turbidity, ammonia, and phosphate. Two media combinations (only blood clam shells [CC] and sand + blood clam shells [SC]) were operated under two different acclimatization periods (14 and 28 d). Results showed that SC medium exhibited significantly higher removal of turbidity (p 0.05) removal of ammonia (23.12 ± 20.2 % vs. 16.77 ± 16.8 %) and phosphate (18.03 ± 11.96 % vs 13.48 ± 12 %). Comparing the acclimatization periods, the 28 d of acclimatization period showed higher overall performances than the 14 d. Further optimizations need to be conducted to obtain an effluent value below the national permissible limit, since the ammonia and phosphate parameters are still slightly higher. SEM analysis confirmed the formation of biofilm on both mediums after 28 d of acclimatization; with further analysis of schmutzdecke formation need to be carried out to enrich the results.

Biocoagulants have gained attention as an alternative to chemical coagulants in water and wastewater treatment due to their ability to remove pollutant parameters such as turbidity, suspended solids, color, and organic compounds. Plant-based biocoagulants are currently the most promising due to their abundant availability and reliable performance. A proper preparation of plant-based biocoagulants is required to ensure the active compounds from the plants can be extracted. Plant raw materials are prepared into biocoagulants using drying and grinding, extraction, and purification. In mechanical preparation, drying and grinding exhibit great influence on the performance of plant-based biocoagulants due to the removal of moisture and higher contact with the carrier medium during dissolution. A smaller biocoagulant's size resulted in up to 78 % higher removal of turbidity. In chemical preparation, the oil needs to be removed before extracting the active ingredients to avoid low active compound extraction yields. The defatting of Moringa oleifera seeds showed an 18 % higher protein content. Salt and alcohol extractions were mentioned as superior extraction methods to obtain carbohydrate and protein from plant-based biocoagulants compared to water extraction, with up to a 5 % increment in turbidity removal. Preparation and pretreatment protocols have a great influence on the properties and performance of plant-based biocoagulants. Further extension of research on plant-based biocoagulants should address the problems in the initial characterization of plant material, standard pretreatment and preparation protocols, and real-scale application of plant-based biocoagulants.

Phytoremediation is one of the green technologies that is friendly to nature, utilizes fewer chemicals, and exhibits good performance. In this study, phytoremediation was used to treat diesel-contaminated sand using a local aquatic plant species, Scirpus mucronatus, by analyzing the amount of total petroleum hydrocarbons (TPHs). Optimization of diesel removal was performed according to Response Surface Methodology (RSM) using Box-Behnken Design (BBD) under pilot-scale conditions. The quadratic model showed the best fit to describe the obtained data. Actual vs. predicted values from BBD showed a total of 9.1 % error for the concentration of TPH in sand and 0 % error for the concentration of TPH in plants. Maximum TPH removal of 42.3 ± 2.1 % was obtained under optimized conditions at a diesel initial concentration of 50 mg/kg, an aeration rate of 0.48 L/min, and a retention time of 72 days. The addition of two species of rhizobacteria (Bacillus subtilis and Bacillus licheniformis) at optimum conditions increased the TPH removal to 51.9 ± 2.6 %. The obtained model and optimum condition can be adopted to treat diesel-contaminated sand within the same TPH range (50–3000 mg/kg) in sand.

Phytoremediation is considered of a cost effective and environmentally friendly technology and has been used successfully for the remediation of soils and water contaminated with various pollutants. Specifically for full scale application to treat industrial wastewater, phytoremediation is used as sole technology for different types of wetlands. However, phytoremediation of polluted water in wetland type reactor has been mostly studied as black box. The method to measure the performance is only based on pollutant removal efficiency and there is very limited information available about of the pollutant removal mechanisms and process dynamics in these systems. Thus, the aim of this chapter was to briefly review basic processes of phytoremediation, its mechanisms and parameters, and its interaction between rhizo-remediation and microbe-plant. In addition, this chapter also elaborated phytoremediation challenges and strategies for full-scale application, its techniques to remove both organic and inorganic contaminants by aquatic plants in water, and some examples of applications in industries.

This study aimed to determine the ability to modify slow sand filter (SSF) media with silica sand or Anadara granosa shells on the efficiency of removal of turbidity, TSS, and iron in the water of Kali Jagir Surabaya as an effort to achieve clean water in disaster areas, to obtain the influence of variables, and to optimize the obtained results. The research data was processed using Design Expert 11 Software which factors consisted of media type, filtering speed, and running time, for the responses of removal efficiencies for each parameter. The reactor was operated continuously for 6 days, and samples were analyzed for turbidity parameters based on Indonesian standard (SNI 06-6989.25-2005); TSS and Iron Standard Method 23rd 3500A. In addition, the results of the parameters were processed using the Analysis of Variance (ANOVA) to show the significant effect of the variables on the efficiency of the elimination of all parameters. Optimal research was achieved in the SSF reactor unit with silica sand media type and filtering speed of 0.1 m/hour turbidity removal efficiency of 82.07%; TSS 89.5%; and 50.14% iron. However, the reactor that was chosen was the filtering speed of 0.1 m/hour with a flow rate of 22.8 L/day, while the SSF was suitable to be applied in disaster areas, which had a large discharge. Hence, the reactor is suitable for use in water sanitation in disaster areas, namely with a filtering speed of 0.3 m/hour which produces a discharge of 68.4 L/day with variations of sand, geotextile, and silica sand media.

This research aimed to discover the macroscopic, microscopic, and physiological characteristics and the genus of heterotrophic bacteria found in the schmutzdecke or biofilm layer in slow sand filters. The isolation of heterotrophic bacteria in the schmutzdecke applied the pour plate and quadrant streak method, while the characterization used macroscopic, microscopic, and physiological tests. Samples were taken from the schmutzdecke on top of the filter layer, and they were diluted 3, 4, and 5 times, then grown in Nutrient Agar media in order to isolate heterotrophic bacteria. The results of the research were analyzed using the identification manual books titled Bergey’s Manual of Determinative Bacteriology, 9th edition and Manual for The Identification of Medical Bacteria, 3rd edition. These manuals show the names of the genus of bacteria in the schmutzdecke layer. On the basis of the identification results from macroscopic, microscopic, and physiological tests, there were 4 dominant genera out of 18 living isolates obtained from the schmutzdecke layer, namely Kurthia gibsonii, Bacillus badius, Bacillus firmus, and Bacillus lentus. The similarity percentage of these 4 isolates was 83%, 81%, 85%, and 77% respectively.

Increasing levels of bisphenol A (BPA), classified as an endocrine-disrupting compound, in the environment have raised concerns because of its detrimental impact on human and animal health. BPA has been detected in soil and water and even as a volatile compound in the air primarily because of improper disposal and its extensive use in the production of polycarbonate plastics and epoxy resins. This review comprehensively surveyed recent research focusing on the removal of BPA from water through physicochemical and biological treatments, covering articles published from 2002 to 2023. A range of conventional and non-conventional methods employed for BPA removal is examined, and their limitations in completely degrading BPA in water are acknowledged. Hybrid or integrated treatment systems have been explored, capitalising on the distinctive removal potential of various treatment processes. The literature spanning from 2002 to 2023 underscores the efficacy of hybrid or integrated treatment systems in yielding promising results for BPA removal from water. Furthermore, future directions for BPA removal are outlined, and advancements in treatment technologies developed over the past decade are incorporated.

Plant combination and rhizobacterial bioaugmentation are the modification of constructed wetlands (CWs) to promote the detoxification of leachate. In this study, characterization of leachate was carried out to ensure the maximum concentration of leachate that did not affect the plant's growth. Herein, the identification of leachate-resistant rhizobacteria is used to determine the type of bacteria that is resistant and has the potential for leachate processing in the next step. The phytodetoxification test is carried out by comparing the addition of rhizobacteria and without the addition of rhizobacteria to detox leachate parameter Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD), Total Suspended Solid (TSS), Total Nitrogen (TN), Cadmium (Cd), and Mercury (Hg). Results showed that used plants could still live in the largest leachate concentration of 100%. The rhizobacteria that were identified and bioaugmented in the reactor were Bacillus cereus, Nitrosomonas communis, and Pseudomonas aeruginosa. Phytodetoxification test by a single plant showed the efficiency ranged between 40% and 70%. The addition of rhizobacterial bioaugmentation and plant combination can improve the percentage of COD 80.47%, BOD 84.05%, TSS 80.05%, TN 75.58%, Cd 99.96%, and Hg 90%. These modifications are very influential for leachate detoxification through plant uptake and rhizodegradation processes.

The use of microalgae for CO2 sequestration helps in mitigating global warming. This paper reviews the application of microalgae for CO2 sequestration with emphasis on performance evaluation, lifecycle, economic assessment, as well as environmental impact. The CO2 sequestration mechanism is done during photosynthesis, via bioconcentration. Performance evaluation revealed that the efficiency of capture and sequestration of CO2 by microalgae ranges between 40% and 93.7%. However, the macro performance of microalgae in carbon emission reduction has not yet been fully understood, and therefore requires more studies. Also, the cost-effectiveness of the CO2 sequestration by microalgae cultivation still needs more research based on recent economic realities. It is recommended that design and operation be focused on cost-effectiveness so the technology can compete favourably with existing technologies. Overall, it can be surmised that the application of microalgae for CO2 sequestration is an effective technique for carbon capture, but still has interesting areas for development for greater global environmental impact.

Seashells waste is abundant in coastal area, especially in the locations where fisheries are a major occupation. This abundant resource of seashells opens a new opportunity further utilization. Seashells waste is a source of CaCO3, which may be converted into CaO via the calcination process. This study analyzed the characteristics of the CaO produced via calcination process at different temperature and calcination time. The calcination process was carried out at a temperature of 800oC, 900oC, and 1000oC with variation of 2, 3, and 4 hours in time. The Fourier transform infrared spectroscopy (FTIR) result showed that the spectrum of 2513 cm-1 as an indication of the C-H group containing CaO appearing after calcination. The FTIR results suggest that the calcination time did not gave major alteration to the functional groups. The results of X-ray diffraction (XRD) analysis showed that CaO laid at the angle of 58.1o and 64.6o. Scanning Electron Microscopy - Energy Dispersive X-Ray Spectroscopy (SEM-EDS) results showed that the most significant compositional outcome after the calcination process was Ca and O at all temperatures and calcination times. All calcined seashells showed rough surface and irregular shape particles. The result of a Thermogravimetric analysis (TGA) suggested that the highest mass alteration occurred at a temperature of 800°C with 78 mins of calcination time.

Bioaugmentation, the addition of cultured microorganisms to enhance the currently existing microbial community, is an option to remediate contaminated areas. Several studies reported the success of the bioaugmentation method in treating heavy metal contaminated soil, but concerns related to the applicability of this method in real-scale application were raised. A comprehensive analysis of the mechanisms of heavy metal treatment by microbes (especially bacteria) and the concerns related to the possible application in the real scale were juxtaposed to show the weakness of the claim. This review proposes the use of bioaugmentation-assisted phytoremediation in treating heavy metal contaminated soil. The performance of bioaugmentation-assisted phytoremediation in treating heavy metal contaminated soil as well as the mechanisms of removal and interactions between plants and microbes are also discussed in detail. Bioaugmentation-assisted phytoremediation shows greater efficiencies and performs complete metal removal from soil compared with only bioaugmentation. Research related to selection of hyperaccumulator species, potential microbial species, analysis of interaction mechanisms, and potential usage of treating plant biomass after treatment are suggested as future research directions to enhance this currently proposed topic.

Abstract Leachate is produced from sanitary landfills containing various pollutants, including heavy metals. This study aimed to determine the resistance of bacteria isolated from non-active sanitary landfill leachate to various heavy metals and the effect of salinity levels on the removal of Hg by the isolated bacterium. Four dominant bacteria from approximately 33 × 1017 colony-forming units per mL identified as Vibrio damsela, Pseudomonas aeruginosa, Pseudomonas stutzeri, and Pseudomonas fluorescens were isolated from non-active sanitary landfill leachate. Heavy metal resistance test was conducted for Hg, Cd, Pb, Mg, Zn, Fe, Mn, and Cu (0–20 mg L− 1). The removal of the most toxic heavy metals by the most resistant bacteria was also determined at different salinity levels, i.e., fresh water (0‰), marginal water (10‰), brackish water (20‰), and saline water (30‰). Results showed that the growth of these bacteria is promoted by Fe, Mn, and Cu, but inhibited by Hg, Cd, Pb, Mg, and Zn. The minimum inhibitory concentration (MIC) of all the bacteria in Fe, Mn, and Cu was > 20 mg L− 1. The MIC of V. damsela was 5 mg L− 1 for Hg and > 20 mg L− 1 for Cd, Pb, Mg, and Zn. For P. aeruginosa, MIC was > 20 mg L− 1 for Cd, Pb, Mg, and Zn and 10 mg L− 1 for Hg. Meanwhile, the MIC of P. stutzeri was > 20 mg L− 1 for Pb, Mg, and Zn and 5 mg L− 1 for Hg and Cd. The MIC of P. fluorescens for Hg, Pb, Mg, and Zn was 5, 5, 15, and 20 mg L− 1, respectively, and that for Cd was > 20 mg L− 1. From the MIC results, Hg is the most toxic heavy metal. In marginal water (10‰), P. aeruginosa FZ-2 removed up to 99.7% Hg compared with that in fresh water (0‰), where it removed only 54% for 72 h. Hence, P. aeruginosa FZ-2 is the most resistant to heavy metals, and saline condition exerts a positive effect on bacteria in removing Hg.

Microbial Salinity Cell (MSC) can simultaneously desalinate water and generate electricity from biodegradation of organic compound in wastewater. The utilization of a three-chambers configuration system along with electrolyte recirculation, create a desalination process which occurs when salt ions from the anode and cathode chambers are accumulated into the middle chamber, driven by the electrical energy generated from organic compound biodegradation. The performance of three-chambers electrolyte recirculation MSC was investigated using three different NaCl concentrations of 2.0 g/L, 4.0 g/L, and 8.0 g/L, with the acetate concentration of 0.82 g/L. At 2.0 g/L NaCl, the maximum power density production was 42.76 mW/m2, increasing conductivity in the middle chamber from 15.09 µS/cm to 0.74 mS/cm. At 4.0 g/L, the maximum power density reached was 53.37 mW/m2, and conductivity in the middle chamber was raised from 60.08 µS/cm to 2.74 mS/cm. At 8.0 g/L, the power density was 29.29 mW/m2 and conductivity in the middle chamber increased from 10.0 µS/cm to1.65 mS/cm. The performance of MSC was correlated with initial NaCl concentration, with optimum NaCl concentration was at 4.0 g/L that able to generate highest power of 53.37 mW/m2 and showed the highest increasing conductivity from 80.8 to 2.74 mS/cm.

Since the implementation of the International Maritime Organization 2004 regulation, most ships have been equipped with on-dock ballast water treatment. While this method is effective in solving the invasive alien species problem, concerns are raised due to the potential release of disinfection by-products (DBPs) as the result of the chemical treatment. This review paper aims to summarize the history of ballast water management (BWM) and the currently used on-dock technology. Chlorination, oxidation, and ozonation are highlighted as the most currently applied methods to treat ballast water on-dock. This paper then focuses on the potential release of toxic DBPs as the result of the selected corresponding treatment methods. Tri-halo methane, haloacetic acid, and several acetic acid-related compounds are emphasized as toxic DBPs with concentrations reaching more than 10 μg/L. The potential toxicities of DBPs, including acute toxicity, carcinogenicity, genotoxicity, and mutagenicity, to aquatic organisms, are then discussed in detail. Future research directions related to the advanced treatment of DBPs before final discharge and analysis of DBPs in coastal sediments, which are barely studied at present, are suggested to enhance the current knowledge on the fate and the ecological impact of BWM.

The reed bed system is one types of phytoremediation technology for removing pollutants from the environment. This technology provides an environmentally friendly approach to treating contamination with competitive cost, compared to the physico-chemical treatment. The design of reed bed system is highly important in order to achieve the highest pollutant removal efficiency. The design of reed bed system affects the natural oxygen transfer from the environment. The reed bed system was proven to have a good efficiency in removing Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Total Dissolve Solid (TDS), Total Nitrogen (TN) and a number of bacteria. In addition to the oxygen transfer from the environment, the interaction among pollutant-plants-medium-microbes also plays a vital role in the removal of pollutant using the reed bed system. It was suggested that the future related research should accommodate the importance of several environmental conditions to the interaction between pollutant, plants, medium and microbes as well as the impact of those interactions on the pollutant removal efficiency.

Chromium in wastewater is classified as one of dangerous contaminants that requires further treatment before it can be discharged to water body. Concentration of chromium in water body, especially river, has increased as many industries are utilizing chromium as raw materials and then discharging its wastewater directly without any treatment. Biosorption is one of methods that widely used to treat heavy metal containing wastewater. Bacteria is the most common microorganism to be used as heavy metal treatment agent. Azotobacter s8, Bacillus subtilis and Pseudomonas putida had been proven to have a heavy metal resistant capability. Screening test showed that Minimum Inhibitory Concentration value of chromium for all bacteria were ranged from 100 to 250 mg/L of CrCl3. Chromium biosorption test by bacteria showed that Azotobacter s8 was able to remove 10.53%, and Bacillus subtilis was able to remove 5.68% chromium from 50 mg/L initial concentration while Pseudomonas putida showed no chromium removal. The chromium biosorption capacity by Azotobacter s8 was 580.08 mg/g and 349.30 mg/g for Bacillus subtilis.

Batik is one of ethnical cultures of Indonesia. The batik production has spread throughout Indonesia. One of the batik industry areas is located in Jetis, Sidoarjo, Indonesia. This industry has been operating for approximately 350 years without processing its wastewater. The batik wastewater contains several toxic compounds such as high BOD, COD and color pigment. These compounds can be harmful for the environment if discharged directly to water bodies. Phyto-treatment might be a solution to overcome this problem. The use of Scirpus grossus and Iris pseudacorus with variations of waste irrigation system using the intermittent method showed a COD removal up to 89% and BOD removal up to 97%. Mixed culture of S. grossus and I. pseudacorus showed a better removal than its single culture. The highest removal of BOD and COD was obtained in reactor with mixed culture plants under Flood/ Drain ratio of 2:1.

Aluminium contaminated soil is currently being a concern due to the use of aluminium waste as a material for building roads and river dams in Jombang District, Jawa Timur Province, Indonesia. These utilization were debated because aluminium waste is categorized as hazardous waste. One widely known method for treating metal contaminated soil is bioremediation. One potential indigenous bacterial species to remove aluminium, Vibrio alginolyticus was isolated from contaminated soil. Toxicity test to V. alginolyticus showed that this bacterium could grow in aluminium contaminated soil until 100 mg/L equal to 48 mg/kg concentration. Removal of aluminium from soil was conducted by using 50 and 100 mg/L concentration. Result showed that the addition of 2% v/v of V. alginolyticus can remove 5.48% aluminium from 100mg/L contaminated soil initial concentration after 12 days of test period. The addition of V. alginolyticus did not significantly influence the removal of aluminium from contaminated soil (p>0.05).

The coffee processing industry produces toxic and low biodegradable effluent, which can pollute water bodies. A pre-treatment study on coffee effluent using a dual-media biofilm reactor (DM-BR) containing sand and Hexafilter (HEX) was conducted alongside a control biofilm reactor (C-BR) containing sand media. The novelty of this study lies in the use of dual media in biofilm reactor (DM-BR) for real coffee effluent treatment, where these processes were used individually in previous studies. The performance of DM-BR and C-BR in treating coffee effluent were investigated at different hydraulic retention times (HRTs), 24, 48 and 72 h, and the degrading bacteria were identified. Both biofilm reactors were inoculated with a recycled paper mill-activated sludge and acclimatised for 97 days. The DM-BR displayed the highest removal of chemical oxygen demand (COD) and NH4+-N at 47% and 38%, respectively, within 48 h of HRT, whereas colour and tannin–lignin reached maximum average removal of 21% and 29%, respectively, at 24 h of HRT. The combination of sand and HEX media in a system showed COD and NH4+-N removal improvement at 48 h of HRT and encouraged a variety of bacterial species growth. Bacterial characterisation analysis revealed Proteobacteria to be dominant.

Wastewater that contain high concentration of nutrients can create instability in water ecosystem if left untreated. Laundry wastewater contain nutrients with high concentration. Nutrients that commonly found in laundry wastewater are nitrogen and phosphorus. This study had a purpose to determine the effect of illumination period and light intensity for the removal of Chemical Oxygen Demand (COD), Nitrogen-ammonia (NH3-N), and phosphate (P) content using Chlorella vulgaris in High Rate Algal Reactor (HRAR) treatment. Variables that used were exposure period of 12 and 24 hours and light intensity of 2000-3000 Lux, 4000-5000 Lux, and 6000-7000 lux. Parameters tested in this study were COD, Nitrogen-ammonia, phosphate to determine the efficiency of nutrient removal and Chlorophyll α to determine the condition of algae development. Results showed that the highest nutrient removal obtained by the reactor with 24 hours illumination period with light intensity of 6000-7000 Lux that able to remove 54.63% of COD, and 22.15% of P. The 12 hours of illumination period was better to remove NH3-N up to 50.07%. Based on the result of statistic test, illumination period did not significantly influence the removal efficiency of COD, NH3-N and P shown by P-value >0.05, while light intensity was significantly affect the removal of COD and NH3-N showed by P value

This research analyses the performance of bacteria-assisted phytoremediation of aluminium (Al)-contaminated soil using native Indonesian plants namely, Scirpus grossus and Thypa angustifolia. A range finding test (RFT) was carried out for 14 days to obtain the tolerable Al concentration for both plants. A total of 2% and 5% (v/v) of Vibrio alginolyticus were bioaugmented during the 28-day phytoremediation test to enhance the overall Al removal. Result of the RFT showed that both plants can tolerate up to 500 mg/kg Al concentration. The addition of V. alginolyticus to the reactors resulted in a significant increment of Al removal from the contaminated soil (p < 0.05). Such addition of V. alginolyticus increased the Al removal by up to 14.0% compared with that without-bacteria addition. The highest Al removal was obtained for S. grossus with 5% V. alginolyticus with an efficiency of 35.1% from 500 mg/kg initial concertation. T. angustifolia with 500 mg/kg initial concentration showed the highest removal of 26.2% by the addition of 5% V. alginolyticus. The increase of Al removal by the bioaugmentation of V. alginolyticus was due to the interaction in the plant's rhizosphere. Exudates of both plants provided a good environment for bacteria to live in the root area. Meanwhile, the bacteria increased the bioavailability of Al to be further extracted by plants. Certain mechanisms, such as rhizostabilisation, phytostimulation and phytoextraction, were considered to be the main processes that occurred during the treatment. S. grossus and T. angustifolia displayed promising ability to act as Al hyperaccumulators with bioaccumulation factor values up to 5.308 and 3.068, respectively. Development of the design of the ex-situ soil phytoremediation reactors is suggested as a future research direction because it can significantly enhance the current obtained finding.

In a slow sand filter, a biological layer consisting of alluvial mud and various types of microorganisms grows and attaches to the sand media and forms a matrix called schmutzdecke. Changes to several factors, including the quality of raw water, filtration speed, and the addition of media, affect the performance of the slow sand filter unit in producing treated water. Geotextiles can be equipped to improve the performance of a slow sand filter in removing pollutants. The selection of several factors that affect slow sand filter performance can be used as a starting point for the engineering system to determine the best pattern of performance behavior. This approach was carried out by looking at the dynamic behavior patterns of slow sand filter system performance in treating raw water. This research has not yet been conducted extensively. The dynamic behavior pattern approach to the performance of the slow sand filter unit was used to obtain the behavior model for the schmutzdecke layer on the filter. The system dynamic approach focused on treatment scenarios that can determine the behavior of the slow sand filter system. Several factors were assessed, including temperature, turbidity, nutrient concentration, algal concentration, bacteria and dissolved oxygen. Model simulation results show that the comparison of C: N: P values affected the performance of the schmutzdecke layer in removing total coli. The slow sand filter unit was capable of producing treated water with a total amount of coli equal to 0 on the C: N: P values of 85: 5.59: 1.25, respectively, and a 9 cm geotextile thickness.

Aluminium recycling is one of currently growing industries in Indonesia. Abundant amounts of aluminium waste leads to the emergence of new industries. The waste produced from this kind of industry is not well processed yet. Bioremediation using isolated indigenous bacteria is one of the best options from treating the aluminium recycling wastewater. Since biological processes are closely related to the bacterial growth conditions, it is important to understand the effect of pH and aluminium exposure to bacteria. Six potential bacteria strains were obtained from isolation. Vibrio alginolyticus and Brochothrix thermosphacta were shown to be resistant to the aluminium exposure, as well as the acidic conditions. Both types of bacteria were able to survive on acid medium with pH 5. The higher the concentration of aluminium, the slower bacterial growth rate achieved. The MIC value of aluminium for Vibrio alginolyticus was 425 mg/l, Brochothrix thermosphacta was 325 mg/l and Pseudomonas aeruginosa was 200 mg/l.

Azo dyes are the largest class of synthetic dyes and are utilized in several industries. Effluents containing dyes are released to the environment and pose harm to humans who might be exposed to these contaminants. This study aims to investigate the removal of methylene blue (MB) dye using duckweed (Lemna minor). L. minor (2 g) was exposed into 50 mg/L of MB dyes for 24 h. The absorbance values were measured at 0, 0.5, 1, 2, 3, 4, 5, 6, and 24 h with a maximum wavelength of 665 nm. The dye removal percentage and relative growth rate of L. minor during exposure to MB were observed. The removal percentage was 80.56 ± 0.44% for 24 h with a relative growth rate of 0.006/h. L. minor has potential as a phytoremediation agent to remove dyes from wastewater.