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Coagulation is an important process to remove organics from water. The molecular composition and structure of organic matter influence water quality in many ways, and the lack of information regarding the organics removed by different coagulants makes it challenging to optimize coagulation processes and ensure reclaimed water safety. In this paper, we investigated coagulation of secondary biological effluent from a municipal sewage treatment plant with different coagulants. We emphasized investigation of organics removal characteristics at the molecular level using Fourier transform-ion cyclotron resonance mass spectrometry (FT-ICR MS) coupled with electrospray ionization (ESI). We found that conventional coagulants can only partially remove condensed polycyclic aromatics and polyphenols with low H/C (H/C < 0.7) and highly unsaturated and phenolic compounds and aliphatic compounds with high O/C (O/C > 0.6). A new coagulant, CBHyC, had better removal efficiencies for all organics with different element compositions and molecular structures, especially organics that are resistant to conventional coagulants such as highly unsaturated and phenolic compounds and aliphatic compounds located in 0.3 < O/C < 0.8 and 1.0 < H/C < 2.0 regions and sulfur-containing compounds with higher O/C (e.g., anionic surfactants and their metabolites or coproducts). This study provides molecular insights into the organics removed by different coagulants and provides data supporting the possible optimization of advanced wastewater treatment processes.

In an experiment of one-pass aerobic fermentation, sawdust was used as the amendment and straw was used as the bulking agent. The forced aeration was at the rate of 0.1 m3/h while the influence of nitrogen and microbe sources on the process was thus investigated. The oil degradation rate was up to 52.7% after fermentation under the conditions of poultry manure as the nitrogen source and HJ-1 strain as the microbe. Simultaneously, the color of oily sludge changed from black to brown, the stink from the manure disappeared, and the appearance of the sludge changed from a sticky state to loose particles. The analytical results indicated that the amount of saturated hydrocarbons in the refinery sludge was decreased remarkably after fermentation.

Three kinds of bacterial strains, HJ-1, HJ-2, and HJ-3, were isolated by means of enrichment culture from oily sludge in Shengli oil field. HJ-1 was identified as Bacillus by primary test. The influence of seed age, oil concentration, microbial quantity experimental time, and pH on the degradation ability of the HJ-1 strains was investigated. The results showed that the oil reduction rate was 69.4% for the refinery oily sludge, and the conditions were as follows:  50 mL, pH 9, oil concentration 5 g·L-1 enrichment culture of crude oil, addition of 12 mL of strain HJ-1 at the seed age of 16 h, experimental time 6 days, then evaluate the fermentation of hydrocarbon-degrading strain HJ-1 in a shake flask. The influencing factors of pH, microbial quantity, glucose concentration, salt concentration, rotation speed, and temperature were also studied. The oil degradation rate of HJ-1strains rose from 78.6% to 82.0% for crude oil and from 69.4% to 77.4% for oily sludge from the refinery, as the fermentation bacteria solution was added into the oily sludge under the optimum conditions.