Zhiqiang Gong

Traditional pumped storage capacity configuration uses static, year-targeted approaches, leading under-capacity in the early planning stages—wasting renewable energy—and over-capacity in later stages, thus wasting resources. In order to solve the above problems, this article innovatively proposes a dynamic, time-sequenced construction timeline and annual capacity configuration strategy, synchronized with new energy and load development, enhancing sustainability through optimized investment allocation and efficient resource utilization. It presents a two-layer model that considers multiple scenario operational dispatch. The upper layer aims to minimize the curtailment of wind and solar energy, providing a planning scheme to the lower layer, which focuses on multi-scenario economic dispatch, taking into account the peak-valley difference indicators. The models co-iterate: lower-layer operational outcomes feed back to refine the upper-layer’s capacity plan. This process continues until the predicted curtailment calculated by the upper layer aligns closely with that observed in the lower-layer operational simulations, or until capacity changes stabilize, ultimately determining the optimal time-phased capacity configuration. Simulations on a provincial power grid during three typical scenarios in winter, transitional seasons, and summer, as well as extreme weather scenarios, confirm that timely, dynamic configuration strategy significantly enhances renewable absorption, proving the model’s effectiveness.

Flue gas desulfurization (FGD) gypsum is one of the most important solid wastes in coal-fired power plants, which is commonly treated to produce building materials. However, chloride ions in the FGD gypsum can degrade the product quality because of their high hydrophilia. Coal fly ash (CFA) is a sustainable additive for the immobilization of chloride ions in preparing FGD gypsum-based plaster, while its reactivity is usually poor. In this study, triethanolamine (TEA) was chosen to stimulate the activity of CFA in the FGD gypsum/CFA blends, and its effects on the chloride ions immobilization were explored. The results showed that the immobilization ratio of chloride ions in the FGD gypsum-based plaster increased to 47.60% after 14 days of curing as 0.10% TEA was added. Besides, the increase of curing time or the addition of TEA could promote the generation of C-S-H gels and chloroaluminate salts, respectively, thereby improving the physical adsorption and chemical binding of chloride ions. Furthermore, TEA optimized the pore structures inside the FGD gypsum-based plaster, which blocked the migration channels of chloride ions. As a result, the immobilization of chloride ions was achieved.

Incineration is a highly effective method for treating oily sludge. However, during the incineration process, heavy metals may either be released into the air via flue gas or remain in the bottom ash in an unstable form, posing significant environmental threats. Mineral compounds can provide adsorption sites for heavy metals and promote the stable existence of heavy metals in incineration bottom ash. In this paper, the incineration experiments of oily sludge with CaO, Fe₂O₃, Al₂O₃ and MgO were conducted using a horizontal tube furnace. The total amount, leaching characteristics, and morphological distribution of heavy metals in the obtained incineration bottom ash were analyzed. The results showed that CaO had a significant adsorption effect on Cu, Cr, Pb, As and Cd. Al₂O₃ exhibited the best leaching inhibition effect on Cr, Zn, Pb, As, and Cd. The influence of mineral compounds on the morphological distribution of heavy metals during incineration was highly dependent on the type of metal. This work will provide crucial theoretical support for the source control of heavy metals during oily sludge incineration and hold important practical significance for achieving the harmless treatment of oily sludge and promoting the development of oily sludge incineration technology.

It is urgent to improve the electrochemical performance of anode for supercapacitors. Herein, we successfully prepare Fe₂O₃/porous carbon composite materials (FPC) through hydrothermal strategies by using oily sludge waste. The hierarchical porous carbon (HPC) substrate and fine loading of Fe₂O₃ nanorods are all important for the electrochemical performance. The HPC substrate could not only promote the surface capacitance effect but also improve the utilization efficiency of Fe₂O₃ to enhance the pseudo-capacitance. The smaller and uniform Fe₂O₃ loading is also beneficial to optimize the pore structure of the electrode and enlarge the interface for faradaic reactions. The as-prepared FPC shows a high specific capacitance of 465 F g⁻¹ at 0.5 A g⁻¹, good rate capability of 66.5% retention at 20 A g⁻¹, and long cycling stability of 88.4% retention at 5 A g⁻¹ after 4000 cycles. In addition, an asymmetric supercapacitor device (ASC) constructed with FPC as the anode and MnO₂/porous carbon composite (MPC) as the cathode shows an excellent power density of 72.3 W h kg⁻¹ at the corresponding power density of 500 W kg⁻¹ with long-term cycling stability. Owing to the outstanding electrochemical characteristics and cycling performance, the associated materials’ design concept from oily sludge waste has large potential in energy storage applications and environmental protection.

This article proposed an original comprehensive thermal treatment coupled with gasification and combustion (CGC) of oil sludge (OS), which was designed to produce hydrogen-rich syngas. Based on the experimental results of OS gasification with steam, the combustion characteristics of char from OS gasification were analyzed by thermogravimetric experiments under different heating rates of 10, 20 and 30 °C/min. The combustion process of OS gasification char can be divided into three stages, including water evaporation, volatile combustion and heavy component combustion. The average values of activation energy (E) obtained by Friedman, FWO and Starink methods were 89.98 kJ/mol, 147.61 kJ/mol and 143.09 kJ/mol, respectively. According to OS gasification and OS gasification char combustion experiments, the comprehensive thermal treatment process CGC of OS was simulated by Aspen Plus. The simulation results showed that increasing both gasification temperature and the mass ratio of steam to OS (SOS) could promote the hydrogen production. Considering energy consumption, the recommended OS gasification temperature, SOS and char combustion temperature were 800 ∼ 900 °C, 0.3 ∼ 0.5, and 900 ∼ 1000 °C, respectively, which could ensure full burning of char and reduce the generation of pollutants. The CGC process could reduce CO₂ emissions by 44.2% from carbon flow analysis.

The efficient recovery and conversion of energy in oily sludge has great prospects. In this article, the main objective is to investigate the impact of the addition of CO₂ during the pyrolysis of oily sludge on energy recovery and conversion by thermogravimetric analysis (TGA) and compare the effect with the traditional pyrolysis effect from the perspective of thermal conversion behavior, products composition, and kinetics analysis. The results of the experiment showed that in the CO₂ atmosphere, the main weight loss temperature of oily sludge was mainly concentrated in the range of 300–500 °C, which is lower than the reaction temperature range of traditional pyrolysis. The yields of CO and H₂ in the products have been greatly improved, and the highest proportion in the gas products can reach 19.29% and 22.38%, respectively. The E_a (activation energy) values of oily sludge were determined to be in the range of 40–120 kJ·mol⁻¹ with the conversion between 0.2 and 0.8 via DAEM, KAS, Starink, and FWO methods, respectively, in which the FWO method has shown the strongest adaptability. The results of this study provide reference values for practical engineering applications.

Oil sludge is a typical hazardous waste in the petrochemical and electric power industry. It has complex components and special properties, and has serious hazards to humans, plants, water, and soil. Therefore, how to realize the effective disposal of oil sludge has become an urgent issue to be solved worldwide. Among the existing oil sludge treatment approaches, combustion has been considered to be a promising technology to realize the large-scale industrial application. In the present work, the characteristics of oil sludge were described in detail. The application and development of oil sludge combustion technology were critically summarized and discussed, including factors affecting combustion, drying process, combustion characteristics, synergistic treatment technology, and formation and control of secondary pollution. Besides, the development of combustion equipment, and integrated thermal treatment technology for oil sludge were prospected. This work can be used for guiding the industrial disposal of oil sludge.

In the aim to go beyond the performance tradeoffs of classic electric double-layer capacitance and pseudo-capacitance, composites made out of carbon and pseudo-capacitive materials have been a hot-spot strategy. In this paper, a nest-like MnO₂ nanowire/hierarchical porous carbon (HPC) composite (MPC) was successfully fabricated by a controllable in situ chemical co-precipitation method from oily sludge waste. Due to the advantages of high surface area and fast charge transfer for HPC as well as the large pseudo-capacitance for MnO₂ nanowires, the as-prepared MPC has good capacitance performance with a specific capacitance of 437.9 F g⁻¹ at 0.5 A g⁻¹, favorable rate capability of 79.2% retention at 20 A g⁻¹, and long-term cycle stability of 78.5% retention after 5000 cycles at 5 A g⁻¹. Meanwhile, an asymmetric supercapacitor (ASC) was assembled using MPC as the cathode while HPC was the anode, which exhibits a superior energy density of 58.67 W h kg⁻¹ at the corresponding power density of 498.8 W kg⁻¹. These extraordinary electrochemical properties highlight the prospect of our waste-derived composites electrode material to replace conventional electrode materials for a high-performance supercapacitor.