Zimmermannmejia8407

In the water treatment process of natural water bodies, a large amount of dredged slurry with high water content is generated and required for treatment. The coagulation-flocculation method can improve the efficiency of separation, and a suitable scheme is of great significance. It is unclear whether there is a significant difference in flocculation and separation of dredged slurries from different sources and which constituents dominate this process. Facing these problems, the tests were conducted for dredged sediments from 10 different sources, including rivers, lake, and ocean. Under the same flocculation conditions, the difference in the increment of particle size d10, the specific resistance of filtration, and the suspended solids (SS) of the supernatant after sedimentation are 0-4.6 times, 0-2.4 orders of magnitude, and 0-4 orders of magnitude, respectively. It was found that the main constituents in the dredged slurries, such as clay minerals, fulvic acid and humic acid, impact on flocculation and separation effects by affecting the zeta potential of the particles. However, there is no single constituent in the dredged slurry which dominates the flocculation and separation effect. When these constituents are incorporated, the zeta potential exhibited in the slurry determines the difference in flocculation and separation effects.Permeable asphalt pavement should be selected according to the rainfall characteristics of the project site, so as to improve the permeable performance and ensure the bearing capacity of the pavement structure. Therefore, taking a city in the central plains urban agglomeration of China as an example, the characteristics of the rainstorm intensity distribution and cumulative rainfall are analyzed, and a combination scheme of drainage surface layer asphalt pavement suitable for rainfall characteristics in this area is proposed. Then, the pavement structure design is systematically carried out based on the permeable capacity and bearing capacity. The results show that under the rainfall conditions in this area, there is no surface runoff on the permeable asphalt pavement with 120 mm drainage surface layer, which is suitable for the medium traffic grade of urban roads with cumulative equivalent axle loads of 10 million to 12 million times.The purpose of this study was to apply the experimental Box-Behnken design (BBD) to evaluate the effect and, therefore, the optimal values of three chosen factors on the efficiency of the UV/H2O2 process to decolorize Ponceau S (PS) aqueous solutions. The factors studied at three levels were the irradiated volume of dye solution, the dye solution turbidity and the H2O2 dosage. The equations generated, analysis of variance (ANOVA), contour plots and response surface plots were used to analyze the relationship between independent variables and the outcomes of experiments. OTS964 cell line The fitted model was significant, with an adjusted coefficient of determination (adj-R2 = 0.9835). The results showed that factors such as H2O2 dosage and irradiated volume were the main parameters that affected the decolorization efficiency of the PS aqueous solution, while the turbidity had a slight effect on the response. In addition, significant values were obtained for irradiated volume and H2O2 dosage interaction and square terms of all studied factors. Furthermore, the optimal conditions for decolorization of the PS aqueous solution were found to be an irradiated volume of 257.59 mL, a turbidity of 13 NTU and an H2O2 dosage of 1.76 mM.This paper is aimed at designing a class of model based extremum-seeking feedback controllers (ESC) for the on-line optimization of biomethane production rate in continuous anaerobic digestion (AD) processes. The ESC scheme is based on the modelling error compensation approach coupled with a first-order gradient estimator. The feedback control law is able to keep the concentration of volatile fatty acids (VFAs) near the unknown optimal setpoint while the methane production rate is maximized. Unlike other ESC algorithms applied to AD processes, the proposed control scheme includes a continuous uncertain estimator and avoids excessive oscillations in the control action. Numerical simulations compare the performance of the proposed ESC controller with traditional perturbation-based and sliding mode based approaches.One of the effective ways to remove halogenated disinfection by-products (DBPs) from drinking water is the application of ultrafiltration technology. However, membrane fouling is an important factor affecting the service life and treatment effect. In this study, the electrocoagulation/oxidation-ultrafiltration (EC/O-UF) process was used to remove the precursor substance that produced DBPs, i.e. dissolved organic matters (DOMs). Operating parameters were optimized from the matching of different flocculant morphology to low concentration DOM. The degree of membrane fouling was characterized by analyzing DOMs concentration and membrane flux. The results showed that the optimal conditions for the production of Alb were current density 10 A/m2, hydraulic retention time 10 min, and initial pH 5.0-7.0. Under these conditions, the production of flocculant Alb could reach 58-61%, 94-97% DOMs were removed by EC/O-UF.This work reports on the fundamental factors influencing inter-foulant and foulant-membrane interactions during simulated dissolved organic matter removal using ceramic nanofiltration. Fouling tests were performed using sodium alginate (SAL), humic acid (HA) and bovine serum albumin (BSA) as model foulants. Fouling potentials of each foulant and their mixtures were investigated using feed solutions containing fixed concentrations of K+, Na+, Mg2+ and Ca2+ with a total ionic strength of 10 mM. The impact of modification by atomic layer deposition on fouling mitigation was also assessed. The flux decline in the first 100 min for single foulants was 4.16 × 10-2, 2.69 × 10-2 and 1.60 × 10-2 Lm-2 for SAL, HA and BSA, respectively. These results demonstrated that for the single foulants, deposition on the membrane surface in the early stages of filtration was primarily governed by membrane-foulant interactions. Interestingly, cake filtration was the least fouling mechanism in feed solutions composed of BSA and SAL (R2 = 0.