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Increasing economy and population result in the rapid growth of solid waste in China, with more than 70% being carbonaceous components. The generated carbon-bearing solid waste is called as organic solid waste (OSW). In this Review, OSWs from both municipal and industrial sources are discussed and divided into municipal solid waste (MSW), organic sludge, polymer solid waste, and biomass-like solid waste, according to their variations in origins and characteristics in China. Agricultural waste (i.e., biomass) and large-scale industrial solid waste (e.g., coal waste) are not considered, because of their well-established fundamentals. Incineration is becoming the most common method of energy recovery for OSW in China, while it has to face the problems of relatively low thermal efficiency, high air pollutant emission, and the high risk of fly ash products. Compared with MSW incinerators, coal-fired power plants own efficient power generation systems and centralized air pollution control devices (APCDs). With the fact that mixed coals are widely used in existing power plants, it is of great significance to study and discuss the current status of cocombustion of OSW and coal in China. In this work, the physicochemical properties of OSW were first introduced, with a subsequent detailed summary on their co-combustion fundamentals, such as devolatilization, ignition, char reactivity, and combustion efficiency, and ash-related issues, including fouling/slagging, high-temperature corrosion, and leaching behavior of ash residue. Furthermore, pollutants emissions regarding conventional pollutant [CO, SO 2 , NO x , HCl, particulate matters (PM)], heavy metals, and hazardous organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed. Some pretreatment methods to reduce the risk of co-combustion were also discussed, including pelletization, drying, torrefaction, hydrothermal carbonization, and low-temperature pyrolysis. Lastly, discussions and perspectives on the future co-combustion technology of OSW with coal were presented. This work aimed to gain systematic knowledge on the co-combustion technology of OSW and coal, providing guidelines for further applications of OSW in power plants in China, as well as other countries in the world.

To assess the effect of TDG on the survival of different sizes of pelagic fish, bighead carp (Hypophthalmichthys nobilis) were subjected to TDG supersaturated water at levels of 125, 130, 135, and 140%. The results showed that apparent abnormal behaviours and symptoms of gas bubble disease (GBD) were observed in bighead carp. The survival probability of large and small juvenile bighead carp declined with increasing TDG levels. The median survival time (ST50) values of large juvenile bighead carp were 74.97 and 31.90 h at 130% and 140% TDG, respectively. While the ST50 of small fish were 22.40 and 6.72 h at the same TDG levels. In comparison to the large juvenile bighead carp, the small juvenile bighead carp showed weaker tolerance to TDG supersaturated water. Furthermore, acute lethality experiments after chronic exposure to TDG were initiated to further investigate the effect of TDG on bighead carp. The juveniles were first subjected to 115% TDG supersaturated water for 96 h. After chronic exposure, live fish were immediately transferred to TDG supersaturated water at levels of 125, 130, 135, and 140%. The results demonstrated that no fish died under chronic exposure and few fish exhibited slight GBD symptoms. The ST50 values for bighead carp subjected to acute exposure after chronic exposure were 61.23 and 23.50 h at 130 and 140%, respectively. Compared with the bighead carp subjected to acute exposure, bighead carp subjected to multiple exposures were more vulnerable to TDG.

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