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In the present work, Zeolite A was modified by using hexadecyltrimethylammonium bromide (HDTMABr) for adsorption of the Congo red (CR) dye from synthetic aqueous solutions. The Modified Zeolite A (MZA) was characterized by XRD, SEM, and FTIR. The influence of solution pH (in the 4-12 range), ionic strength (0.1-1 M), contact time (180 min), initial CR concentration (20-60 mg/L), temperature (24-36 °C), and an adsorbent dose (1-3 g m/L) on the % dye removal and adsorbent capacity were studied. A combined effect of the initial CR concentration and temperature on the CR removal % by MZA was also studied by applying response surface methodology (RSM). Experimental values were in a good agreement with those predicated by a second-order quartic model. A maximum of 99.24% dye removal and adsorbent capacity of 21.11 mg/g was achieved under the following conditions pH = 7, initial CR concentration = 60 mg/L, temperature = 24 °C, ionic strength = 0.1 M, adsorbent dose = 3 g/L and 90 min contact time. The equilibrium data were subjected to the Langmuir, Freundlich and Temkin isotherms, with the latter providing the best fit while kinetic adsorption studies were conducted by applying three models. The results indicated that the removal process was best described by the pseudo-second-order model. The present study demonstrates that modified MZA can be utilized for the highly efficient CR dye removal.Conventional biological treatments used in most Indonesian landfill sites are mostly ineffective in treating stabilized landfill leachates to meet the standard regulation. Thus, a combination of biological and electrochemical process is offered to successfully treat leachates containing a high concentration of organic and nitrogenous compounds. In this study, a moving bed biofilm reactor (MBBR) was applied prior to electrochemical oxidation by using boron-doped diamond (BDD), Ti/IrO2, and Ti/Pt anodes with applied current of 350, 400 and 450 mA. The objectives were to investigate the effect of anode type and the applied current on the removal of organics as well as total nitrogen from the MBBR-treated leachate with electrochemical oxidation. The optimum removal of chemical oxygen demand (COD) observed on the Ti/Pt anode was 78% by applying 400 mA, with an estimated energy of 56.7 Wh g L-1. In the case of Ti/IrO2 and BDD anodes, the optimum removal of COD was 76 and 85% with an energy consumption of 58.9 and 36.9 Wh g L-1, respectively, both achieved at 350 mA. Although all anodes showed less-satisfactory performances for total nitrogen reduction, around 46-95% removal of nitrogenous compounds was achieved by MBBR, with their partial conversion to nitrates.The rapid overcompensatory growth that appears when cyanobacteria are supplied with adequate resources after a period of resource deprivation might contribute to the occurrence of cyanobacterial blooms. We investigated the changing characteristics of overcompensatory growth and serine/threonine kinase (STK) genes expression of cyanobacterium Microcystis aeruginosa in response to light limitation. The results showed M. aeruginosa exhibited overcompensatory growth for 2 days after light recovery, during which the increase in growth was inversely related to light intensity. Expression of STK genes, such as spkD, was upregulated significantly at 0.5-4 h after light recovery (P less then 0.05). To investigate the function of STK genes in the overcompensatory growth, M. aeruginosa spkD was heterologously expressed in Synechocystis. Transgenic Synechocystis exhibited greater and longer overcompensatory growth than wild-type Synechocystis after light recovery. Relative expression levels of STK genes in transgenic Synechocystis were significantly higher than those in wild-type Synechocystis at 24 h of light recovery (P less then 0.05). Heterologous expression of Microcystis spkD might stimulate overcompensatory growth of Synechocystis by affecting its STK gene expression.This study highlights the need to increase our understanding of the interplay between sensor drift and the performance of the automatic control system. The impact from biased sensors on the automatic control systems is rarely considered when different control strategies are assessed in water resource recovery facilities. Still, the harsh measurement environment with negative effects on sensor data quality is widely acknowledged. Simulations were used to show how sensor bias in an ammonium cascade feedback controller impacts aeration energy efficiency and total nitrogen removal in an activated sludge process. Response surface methodology was used to reduce the required number of simulations, and to consider the combined effect of two simultaneously biased sensors. The effects from flow variations, and negatively biased ammonium (-1 mg/L) and suspended solids sensors (-500 mg/L) reduced the nitrification aeration energy efficiency by between 7 and 25%. Less impact was seen on total nitrogen removal. There were no added non-linear effects from the two simultaneously biased sensors, apart from an interaction between a biased ammonium sensor and dissolved oxygen sensor located in the last aerated zone. Negative effects from sensor bias can partly be limited if the expected bias direction is considered when the controller setpoint-limits are defined.Three carbon sources, namely sodium acetate, sewage and effluent, were used to simulate the process of phosphorus release in an actual sewage treatment plant, in order to explore the phosphorus release performance of the sludge, the relationship between phosphorus release and chemical oxygen demand (COD) in sewage, and the stability of phosphorus-rich sludge. The results showed that the type and concentration of carbon sources had significant effects on the rate of phosphorus release, reaction equilibrium time and phosphorus release amount. When sodium acetate was used as the carbon source, the phosphorus release rate reached 12.54 mg P (g VSS·h)-1, and tended to be stable at 4.0 hours. The phosphorus release amount in the first 2.5 hours accounted for 36.88% of the total phosphorus in the sludge. When sewage was used as the carbon source, the phosphorus release rate did not reach equilibrium even at 5.0 hours, and the phosphorus release amount increased by 1.0 mg L-1 for every 10.5 mg L-1 increase sewage COD within a certain range. When effluent was used as the carbon source, the visual phosphorus release amount was only 0.83 mg L-1 after standing for 24 hours and the actual phosphorus release amount was 17.98 mg L-1. These conclusions can provide technical support for the optimization of phosphorus removal in sewage treatment plants.The aim of this study was to provide technical means and data support for enhancing the filtration pretreatment capacity of a recirculating aquaculture system. A continuous flow electrocoagulation (EC)-filtration system was designed and its application in the pretreatment of marine aquaculture wastewater was studied. The influences of anode combination modes, hydraulic retention times (HRTs) of the EC reactor and filter pore sizes on the water treatment capacity were investigated. Results showed that EC could significantly enhance the treatment efficiency of the filtration equipment used in subsequent steps. Al-Fe electrodes used as anode led to better processing capacity of this system, and the optimum anode was 3Al + Fe. With the increase of HRT and decrease of filter pore size, the enhanced effect of the EC process on the filter was more obvious. When the current density was 19.22 A/m2, the anode was 3Al + Fe, the HRT was 4.5 min and the filter pore size was 45 μm, the removal efficiency of the system for Vibrio, chemical oxygen demand, total ammonia nitrogen, nitrite nitrogen (NO2--N), nitrate nitrogen (NO3--N) and total nitrogen was 69.55 ± 0.93%, 48.99 ± 1.42%, 57.06 ± 1.28%, 34.09 ± 2.27%, 18.47 ± 1.88% and 55.26 ± 1.42%, respectively, and the energy consumption was (26.25 ± 4.95) × 10-3kWh/m3.In this study, a mesoporous carbon (CMK-3) was successfully synthesized using mesoporous silica (SBA-15) prepared from gold mine tailings (sample CGMT) for removal of anionic dye from aqueous solution. For comparison, CMK-3 was prepared by the same method from pure silica (sample CT), and the other CMK-3 sample was prepared by a one-pot route mixing with Pluronic P123 (sample CP). The effect of the carbonization time on the synthesis of all CMK-3 samples was investigated, and the samples were characterized by X-ray diffraction and N2 adsorption-desorption. The sample with the highest surface area was chosen as an adsorbent, for each CMK-3 obtained from different methods. Selleckchem Aprotinin Batch adsorption experiments were studied to determine the influence of pH, contact time, and initial dye concentration. The adsorption kinetics obeyed the pseudo-second-order model. All carbon-based adsorbents were observed to be quite effective for the removal of dye with adsorption percentage in the order of CP > CT > CGMT. The maximum adsorption capacities were 188.99 and 204.57 mg·g-1 for CT and CGMT, respectively. The comparative results of all carbon-based adsorbents show that CGMT can be applied as a low-cost alternative to CT for dye removal.Storm geysers increasingly occur in sewer systems under climate change and rapid urbanization. Mitigation measures are in great demand to avoid safety problems. In this study, three-dimensional computational fluid dynamics models of single-inlet and multi-inlet systems were established to investigate geysering induced by rapid filling and assess the effectiveness of potential mitigation methods. The modeling results suggest that increasing the capacity of the downstream pipe before the inflow front reaches the chamber can effectively reduce the maximum geyser pressure. The peak pressure can be significantly mitigated when the chamber size is designed with care and the drop height between the upstream and downstream pipes is reduced. A diversion deflector with air vents and an orifice plate at the riser top end can alleviate the maximum pressure by about 65% with about 75% of the entrapped air being released. The peak pressure during the geyser event in the multi-inlet model is less than that of a single-inlet model under the same total inflow condition, but more water can be released.Ultraviolet-activated permanganate (UV/PM) process is a novel advanced oxidation process (AOP), but its application potential remains to be evaluated. This work investigates the degradation of refractory organic pollutant by UV/PM in terms of efficiency, mechanism, and influencing factors. The target compound benzoic acid (BA), which is a micro-organic pollutant and is resistant to PM and UV treatment, can be efficiently degraded by UV/PM. The electron paramagnetic resonance spectra directly supported the formation of hydroxyl radical (HO•) and superoxide radical (O2•-) from UV photolysis of PM. Competitive kinetics experiments verified that O2•- acted as precursor of HO• and the good degradation performance of BA was due to the involvement of HO• and manganese(V). The rate constants of BA degradation showed a positive linear relationship with PM dosage in the range of 0.5-20 mg·L-1, and the degradation process was significantly influenced by solution pH and natural organic matters but insensitive to chloride and bicarbonate at environmentally relevant concentrations.