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With the rapid development of industrialization, the amount of copper-containing wastewater is increasing, thereby posing a threat to the aquatic ecological environment and human health. Sludge biochar has received extensive concern in recent years due to its advantages of low cost and sustainability for the treatment of heavy-metal-containing wastewater. However, the heavy-metal-adsorption capacity of sludge biochar is limited. This study prepared a sodium pyrophosphate- (Na4P2O7-) modified municipal sludge-based biochar (SP-SBC) and evaluated its adsorption performance for Cu(II). Results showed that SP-SBC had higher yield, ash content, pH, Na and P content, and surface roughness than original sewage sludge biochar (SBC). The Cu(II)-adsorption capacity of SP-SBC was 4.55 times than that of SBC at room temperature. For Cu(II) adsorption by SP-SBC, the kinetics and isotherms conformed to the pseudo-second-order model and the Langmuir–Freundlich model, respectively. The maximum adsorption capacity of SP-SBC was 38.49 mg·g−1 at 35°C. Cu(II) adsorption by SP-SBC primarily involved ion exchange, electrostatic attraction, and precipitation. The desired adsorption performance for Cu(II) in the fixed-bed column experiment indicated that SP-SBC can be reused and had good application potential to treat copper-containing wastewater. Overall, this study provided a desirable sorbent (SP-SBC) for Cu(II) removal, as well as a new simple chemical-modification method for SBC to enhance Cu(II)-adsorption capacity.

The construction of emerging engineering is an important content for higher engineering education in China in the new era. The emerging engineering requires the renewal of the ideas and model of talents cultivation. In view of this, establishing a suitable multi-dimensional evaluation system for teaching quality in Chinese colleges and universities is one of the important works under the background of emerging engineering. In the study, the matters needing attention in the construction of the multi-dimensional evaluation system for teaching quality (MESEQ) were analyzed. Then, MESEQ was established, which consisted of 7 primary indexes and 33 secondary indexes. At last, the rationality and the considerations of the application of MESEQ were analyzed. In general, this study constructed an effective MESEQ under the background of emerging engineering. The MESEQ established in this study can provide a guarantee for the training of high-quality and high-level engineering talents in the new period.

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In this work, sodium pyrophosphate (SP) was used as a modifier to prepare the sodium pyrophosphate modified municipal sludge biochar (SP-MSB) for effectively adsorbing Cu in aqueous solution. Four modification factors, i.e., SP concentration factor, impregnation time factor, impregnation solid-liquid ratio factor, and impregnation temperature factor, were investigated to explore the suitable modification condition for the preparation of SP-MSB. In addition, the Cu adsorption efficiencies of the SP-MSB under the suitable modification condition and the unmodified municipal sludge biochar (MSB) were preliminarily evaluated. The results showed that the suitable modification condition for the preparation of SP-MSB was SP concentration of 60 g/L, impregnation time of 10 h, impregnation solid-liquid ratio of 1:30, and impregnation temperature of 25 °C. The Cu adsorption capability of the SP-MSB was 6.37 times than that of MSB, indicating that the SP-MSB can be used as an alternative adsorbent to adsorb Cu in aqueous solution.

The aim of this study was to ascertain the evolution of Cr, Cu, Mn, and Zn during the composting process of chicken manure and their integrated potential ecological risk. This study detected the total amounts of Cr, Cu, Mn, and Zn in 4 samples collected at four different stages in the composting workshop of an intensive chicken farm in Chengdu, China. Furthermore, the chemical fractionation of the four heavy metals was analyzed by the BCR (European Community Bureau of Reference) three-step sequential extraction procedure for each sample. At last, the integrated potential ecological risk of Cr, Cu, Mn, and Zn in the compost at four different stages was evaluated by the procedure of potential ecological risk assessment based on its results of chemical fractionation of Cr, Cu, Zn, and Mn. During the composting process, the total amounts of Cr, Cu, Zn and Mn presented an increasing trend, significantly. Nevertheless, the residual fraction (Res-F) percentage of Cr, Zn, and Cu increased, and the acid extractable fraction (Aci-F) percentage of Mn decreased. The value of integrated potential ecological risk of the four heavy metals in the final product was 9.91. These results indicated the integrated potential ecological risk of the four heavy metals is low. This study provided a support on the promotion and utilization of compost for the intensive chicken farms in China.