The purpose of this study is to investigate the enhancement of polycaprolactone (PCL) on total nitrogen (TN) removal of coal pyrolysis wastewater (CPW) with low COD to nitrogen ratio by partial nitrification-denitrification bioprocess (PNDB) in one single reactor. With the innovative combination of PCL and PNDB, the TN removal efficiency in the experimental reactor (signed as R1) was 10.21% higher than control reactor (R2). Nitrite accumulation percentage (NAP) in R1 was 82.02%, which was 17.49% higher than R2 at the dissolved oxygen (DO) concentration of 0.9–1.5 mg/L, for the reason that the extra DO was consumed by PCL biodegradation at the aerobic period. Gel permeation chromatography (GPC) results demonstrated that organics with the molecular weight of 185 Da, which could serve as additional carbon sources for denitrifiers, were generated during the PCL hydrolysis process at the anoxic period. PCL was hydrolyzed by extracellular enzymes with the break of the ester bond which was confirmed by FT-IR spectrometer. Microbial community analysis revealed that Ferruginibacter was the dominant hydrolysis bacteria in R1. Nitrosomonas were the main ammonium-oxidizing bacteria (AOB) and Hyphomicrobium were the denitrifiers in this study.
Coal is not only an important energy source in China but also a major source of air pollution. Because of this, China’s national
sulfur dioxide (SO2) emissions have been the highest in the world for many years, and since the 1990s, the territory of China’s south and southwest
has become the third largest acid-rain-prone region in the world. In order to control SO2 emissions, the Chinese government has formulated and promulgated a series of policies and regulations, but it faces great
difficulties in putting them into practice. In this retrospective look at the history of SO2 control in China, we found that Chinese SO2 control policies have become increasingly strict and rigid. We also found that the environmental policies and regulations
are more effective when central officials consistently give environmental protection top priority. Achieving China’s environmental
goals, however, has been made difficult by China’s economic growth. Part of this is due to the practice of environmental protection
appearing in the form of an ideological “campaign” or “storm” that lacks effective economic measures. More recently, better
enforcement of environmental laws and regulations has been achieved by adding environmental quality to the performance assessment
metrics for leaders at all levels. To continue making advances, China needs to reinforce the economic and environmental assessments
for pollution control projects and work harder to integrate economic measures into environmental protection. Nonetheless,
China has a long way to go before economic growth and environmental protection are balanced. 相似文献
Adsorption equilibria of phenol and aniline onto nonpolar macroreticular adsorbents were investigated in single and binary-solute aqueous systems at 293 K and 313 K. All adsorption isotherms can be well represented by the Langmuir equation. Larger uptake of aniline than phenol onto all the adsorbents probably results from the higher hydrophobicity of the former compound as well as the greater electronic density of the aromatic ring of aniline. It is interestingly observed that at a relatively high loading, the total uptake of phenol and aniline in a binary system is remarkably higher than those in a single system. Such uptake difference was elucidated by the cooperative effect arising from the lateral acid–base interaction between the loaded phenol and aniline molecules. Moreover, larger average pore size of the adsorbent is found to result in a greater cooperative coefficient, as observed from the equimolar phenol/aniline adsorption system. 相似文献