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The ability to forecast key features of wastewater treatment plant (WWTP) influent, is emerging as an important tool to enable advanced WWTP operational strategies. Various data driven models have been reported in the scientific literature for WWTP influent however, there has been no quantitative comparison of them against each other. The present study is the first to undertake this comparison utilising a high-frequency reference dataset generated from the Urban Water System model. Specifically, the performance of autoregressive models was compared against time-delay networks, nonlinear autoregressive networks and long short-term memory networks. Time-delay networks were generally found to outperform the other tested methods, although the reliability of the generated forecasts decreases as the prediction horizon exceeds one hour. While longer prediction horizons would be desirable, there is a trade-off between model accuracy and overall optimisation of plant operation. This study also highlights the challenge of dealing with both concentration and flow variations suggesting the need for future research to analyse the separate impacts of flow and concentration variations on model performance.

Drying behavior of the poultry abattoir sludge (PAS) was explored for the first time.Drying time decreased by half when thickness of PAS was decreased by five times.Thin-layer drying kinetics was best represented by Page and logarithmic models.Air circulation increased drying rate of PAS and decreased total drying time by 26%.Renewable solar energy could be a sustainable method for drying of by-product sludges.

Abstract: Adsorption potential of the struvite (recovered from the high-strength ammonium-rich synthetic wastewater) was explored for the first time for the removal of an anthraquinone dye (Remazol Brilliant Blue R, RBBR) from aqueous phases. According to the experimental findings obtained from the RBBR-struvite adsorption system, the maximum dye removal efficiency (≈ 79%) was achieved at pH of 2.0, adsorbent dose of 40 g/L, initial dye concentration of 80 mg/L, contact time of 60 min, and temperature of 60 °C. Adsorption isotherms showed that both Langmuir and Freundlich isotherm models fitted very well to the experimental data (R2> 0.990), and adsorption kinetics were satisfactorily described by the Ho and McKay’s PSO kinetic model (R2≈ 0.990). Based on the Langmuir isotherm model, the maximum adsorption capacity of the struvite for the RBBR dye was determined as 21.73 mg/g. The sample exhibited a mesoporous structure and had a BET surface area of 16.35 m2/g. Thermodynamic parameters (ΔG°, ΔH°, and ΔS°) confirmed that the adsorption of the RBBR dye onto the struvite was spontaneous and endothermic in nature and reflected the enhanced degree of disorderliness at the solid/liquid interface, respectively. A MIMO (multiple inputs and single output) Mamdani-type fuzzy inference system was developed for the first time in modeling of the RBBR-struvite adsorption system. The proposed fuzzy logic model showed a superior prediction performance (R2≈ 0.980) when compared to the conventional multiple regression methodology. Overall experimental and statistical results confirmed that struvite could be used as a promising adsorbent material for anthraquinone dye removal from aqueous solutions. Graphic Abstract:

Abstract: To eliminate roof-control disasters typically encountering in mines with thick and hard rock strata, fracture characteristics, instability mechanism and prevention methods were investigated in the study. A mine stope with thick and hard main roof and wedge-structure immediate roof in Zhuxianzhuang Coal Mine was taken as the background. In terms of the strata behaviors and roof control difficulty levels via physical simulations, mining zones were classified into strong pressure behavior zone, less-strong pressure behavior zone and pressure mitigation zone. Theoretical analysis was used to study the interaction characteristics of the support-surrounding rock under different mining zones and the principles and methods of zonal control under THR were proposed. A coordinated control method, which combined confined blasting in water-filled deep holes for reducing the roof fracture size and reasonable support optimization for increasing the supporting intensity, was applied to the strong pressure behavior zone and less-strong pressure behavior zone. The mechanical calculation model of a “presplit-THR-block–immediate-roof-top-block–top-coal-wall–hydraulic-support” system was established, which determined the length of confined blasting blocks as 20–25 m and supporting intensity as 1.15–1.28 MPa. These parameters can satisfy the requirements of THR control and lead to the best economic performance. Article Highlights: Study the fracture characteristics and instability migration law of THR, could be found in 3.1 Structural characteristics of the THR in close distance during the first weighting part. Divide the mining zones based on the strata behaviors and roof control difficulty, could be found in 3.1 Control zones of THR part. The principles and methods of zonal control under THR were proposed, could be found in 3.2 Zonal control principles and methods for THR, 3.3 Mechanical model of pre-control of THR in close distance and determination of working resistance, and the 3.4 Pre-control technology for THR in close distance part.