Modeling and multi-objective optimization for ANAMMOX process under COD disturbance using hybrid intelligent algorithm.

Anaerobic ammonium oxidation (ANAMMOX) has been regarded as an efficient process to treat nitrogen-containing wastewater. However, the treatment process is not fully understood in terms of reaction mechanisms, process simulation, and control. In this paper, a multi-objective control strategy mixed soft-sensing model (MCSSM) is developed to systematically design the operating variations for multi-objective control by integrating the developed model, a least square support vector machine optimized with principal component analysis (PCA-LSSVM) and non-dominated sorting genetic algorithm-II (NSGA-II). The results revealed that the PCA-LSSVM model is a feasible and efficient tool for predicting the effluent ammonia nitrogen concentration ([Formula: see text]) and the total nitrogen removal concentration (CTN, rem) with determination coefficients (R2) were 0.997 for [Formula: see text] and 0.989 for CTN, rem, and gives us the reasonable solutions in influent by using NSGA-II. To achieve a better removal effect, the influent pH should be kept between 7.50 and 7.52, the COD/TN ratio is suggested to maintain at 0.15 and the NH4+-N/NO2--N ratio is suggested to maintain at 0.61. The developed MCSSM approach and its general modeling framework have a high potential of applicability and guidance to bioprocess in wastewater treatment, and numerical models can be structured for predicting and optimization and experiments can be conducted for data acquisition and model establishment.

[MIL-88A@MIP Activated Persulfate for Targeted Degradation of Dibutyl Phthalate].

MIL-88A@MIP was fabricated for the first time in this experiment with a metal-organic framework of MIL-88A as the precursor based on the molecular imprinting method. It was characterized by X-ray diffraction (XRD), scanning electronic microscopy (SEM), energy dispersive spectrometer (EDS), and N2 adsorption. The catalytic performance of MIL-88A@MIP was tested to activate persulfate (PS) to generate SO4-· for the degradation of dibutyl phthalate (DBP), which was used as a target pollutant. Compared with the precursor MIL-88A, the catalytic activity of MIL-88A@MIP was improved effectively through targeted modification, and the DBP removal rate increased 80.4% after reacting for 480 min. An experiment determining the influencing factors showed that the optimum activation condition of the catalyst was PS:DBP=600:1, MIL-88A@MIP dosage of 0.5 g·L-1,and pH=3.26. Furthermore, MIL-88A@MIP shows a high capability of removing different phthalic acid ester (PAE) contaminants that reflect its targeting selectivity.

[Removal of Sulfate Ions from Aqueous Solution by Adsorption with Hydrotalcite- like Composite].

Hydrotalcite-like composite synthesized by co-precipitation method was used as an adsorbent to remove the sulfate ions in aqueous solution. XRD, FT-IR , SEM and EDS elemental analysis were used to clarify the structure and composition of the hydrotalcite- like composite. The influences of time, initial pH value and coexisting ions on adsorption performance were investigated. The result showed the material was the composite of zinc aluminum nitrate hydrotalcite-like compounds and zinc aluminum phenylalanine hydrotalcite-like compounds. Hydrotalcite-like composite had a good performance in adsorption of sulfate ions, and the maximum adsorption capacity was 52.75 mg · g⁻¹. The data fitted pseudo-second order kinetic model best, which indicated that chemical adsorption was the rate-limiting step. Freundlich isotherm was more suitable to describe the adsorption process, and this meant the adsorption of sulfate ions by hydrotalcite-like composite was multilayered adsorption. Thermodynamic parameters showed that the adsorption process was endothermic and spontaneous at room temperature. Hydrotalcite-like composite adsorbed sulfate ions mainly through ion exchange, electrostatic force and physical adsorption. The experimental results showed that the hydrotalcite-like composite had potential for sulfate ion removal in the aqueous solution.