Metagenomic analysis reveals enhanced sludge dewaterability through acidified sludge inoculation: Regulation of Fe (II) oxidation electron transport pathway.

The bioleaching utilizing indigenous microbial inoculation can continuously improve the dewaterability of sludge. In this study, metagenomic analysis was innovative employed to identify the key microorganisms and functional genes that affect the dewatering performance of sludge in the bioleaching conditioning process. The results demonstrated that long-term repeated inoculation of acidified sludge resulted in increased abundance of many functional genes associated with the transport of carbohydrate and amino acid.

Enhancement of sludge dewaterability using combined technology of bioleaching and Fenton: Microscopic structure and hydrophilic/hydrophobic properties of sludge particles.

Bioleaching and Fenton technology are commonly used preconditioning techniques for sludge dewatering. This study compared the dewatering mechanisms of different conditioning technologies. The results showed that bound water, specific resistance to filtration (SRF), and capillary suction time decreased from 3.

The role of microstructure of extracellular proteins in dewaterability of alkaline pretreatment sludge during bioleaching.

Alkaline pre-treatment is known to enhance the acid production efficiency of sludge but adversely affects its dewatering performance. In this study, the improvement of sludge dewaterability by a novel bioleaching system with inoculating domesticated acidified sludge (AS) and its underlying mechanism were investigated. The results showed that although the addition of Fe and the reduction of pH improved the dewatering performance of sludge, their effects were inferior to that of AS + Fe.

Enhancement of sludge dewaterability by repeated inoculation of acidified sludge: Extracellular polymeric substances molecular structure and microbial community succession.

Improving the dewatering performance of sewage sludge is of great scientific and engineering significance in the context of accelerated urbanization and increasingly strict environmental regulations. Acidified sludge (AS) can improve sludge dewatering performance, but the dewatering effect of repeated inoculation is unclear. The effects of long-term repeated inoculation of AS on the sludge dewaterability were investigated.

Synergistic effect of yeast integrated with alkyl polyglucose for short-chain fatty acids production from sludge anaerobic fermentation.

An efficient strategy for short-chain fatty acid (SCFA) production from sludge anaerobic fermentation was proposed with the combination of yeast and alkyl polyglucose (APG). It revealed that the synergetic effect of yeast and APG could boost the SCFA concentration to the maximum value of 2800.34 mg COD/L within 9 days at 0.

Effects of urease inhibitors on enzymatic activities and fungal communities during the biosolids composting.

This study evaluated the influences of urease inhibitors (UIs) on nitrogen conversion, enzyme activities, and fungal communities during aerobic composting. Results showed that UI addition reduced NH emissions by 22.2% and 21.

Combined addition of biochar and garbage enzyme improving the humification and succession of fungal community during sewage sludge composting.

The influences of combination of garbage enzyme and biochar on total organic carbon (TOC) degradation, humification and the fungal succession during sewage sludge (SS) composting were established. Results showed that the GE and BC + GE treatments significantly increased the enzyme activity of fluorescein diacetate hydrolase (FDA) and increased the TOC degradation rate by 9.8% and 21.

Sludge disintegration and phosphorus migration in anaerobic fermentation of waste activated sludge by the addition of EDTA-2Na.

The effects of the addition of EDTA-2Na on sludge disintegration and phosphorus (P) migration during anaerobic fermentation (AF) of waste activated sludge (WAS) are investigated. The efficiency of sludge disintegration was positively correlated with the dose of EDTA-2Na from 0.5-2.

Enhancements of short-chain fatty acids production via anaerobic fermentation of waste activated sludge by the combined use of persulfate and micron-sized magnetite.

The combination of persulfate (PDS) with micron-sized magnetite (FeO) was introduced into the process of anaerobic fermentation (AF) to scrutinize the short chain fatty acid (SCFA) production from waste activated sludge for the first time. The synergetic effect of PDS and FeO results in the promotion of intracellular and extracellular substance liberation, augment in key hydrolases activities, and enrichment of hydrolytic and acidifying microbial population. Meanwhile, carbohydrate, amino acid, and energy metabolism as well as enzymes, are considerably accelerated.

Comparative evaluation of biochar, pelelith, and garbage enzyme on nitrogenase and nitrogen-fixing bacteria during the composting of sewage sludge.

This study investigated the effects of garbage enzyme (GE), pelelith (PL), and biochar (BC) on nitrogen (N) conservation, nitrogenase (Nase) and N-fixing bacteria during the composting of sewage sludge. Results showed that the addition of GE, PL, and BC reduced NH emissions by 40.9%, 29.

Effect of potassium persulphate addition on sludge disintegration of a mesophilic anaerobic fermentation system.

Persulphates, an advanced oxidation process, has been recently used as an alternative pretreatment method to enhance short-chain fatty acids (SCFAs) yield from waste-activated sludge (WAS) anaerobic fermentation (AF). But so far, the effects of peroxydisulphate (PDS) dosages on mesophilic anaerobic fermentation are still not studied fully. Herein, we explored the influences of potassium PDS addition on mesophilic AF of WAS.

Use of additives in composting informed by experience from agriculture: Effects of nitrogen fertilizer synergists on gaseous nitrogen emissions and corresponding genes (amoA and nirS).

The effects of two nitrogen fertilizer synergists (urease inhibitor, UI; nitrification inhibitor, NI) on NH and NO emissions and the successions of the amoA and nirS genes during composting were assessed. Results showed that the UI and UI + NI treatments reduced NH emissions by 26.3% and 24.

Influence of reusable polypropylene packing on ammonia and greenhouse gas emissions during sewage sludge composting-a lab-scale investigation.

Bulking agents are particularly important for sewage sludge composting. In this study, reusable polypropylene packing (RPP) was mixed with sawdust to improve composting. The effect of the mix ratio of sawdust and RPP on the physicochemical characteristics, nitrogen transformation, and emissions of greenhouse gas (GHG) as well as differences in the germination index values was detected in a lab-scale composting experiment.

Composting pig manure and sawdust with urease inhibitor: succession of nitrogen functional genes and bacterial community.

Understanding the relationship between nitrogen (N) cycle and N transformation-related functional genes is crucial to reduce N loss during composting process. Urease inhibitor (UI) is widely used to reduce N loss in agriculture. However, the effects of UI on N transformation and related N functional genes during composting have not been well investigated.

Adding Phosphate Fertilizer and Apple Waste to Pig Manure during Composting Mitigates Nitrogen Gas Emissions and Improves Compost Quality.

Calcium superphosphate and apple ( Mill.) waste can be used for controlling N loss and improving compost quality during composting, whereas integrated addition of the two additives on composting process remains unexplored. Therefore, this study was conducted to investigate the effects of combined use of calcium superphosphate and apple waste on NH and NO emissions and compost quality during pig manure and wheat ( L.

[Interannual Variation of Metal Elements and Water-Soluble Ions in PM During Wintertime in Xinxiang and Their Source Apportionment].

To study the interannual variations of chemical composition and source apportionment, a field campaign was carried out to collect the PM temperance sample during the winter of 2015 and the winter of 2016 in Xinxiang urban areas. PM mass concentration, metal elements, and the water-soluble ions were determined and meteorological factors were recorded simultaneously. The results showed that the daily mean concentrations of PM indicated serious pollution with values of 226 μg·m and 224 μg·m in 2015 and 2016, respectively.

[Seasonal Variation and Source Analysis of Water-soluble Inorganic Ions in Fine Particulate Matter in Zhengzhou].

In order to explore the characteristics of PM concentration and water-soluble inorganic ions in Zhengzhou City, a total of 170 PM samples were collected in the spring, summer, autumn, and winter seasons of 2016, with 30 days continuous sampling during each season. The mass concentration of PM was analyzed gravimetrically, water-soluble inorganic ions were determined by ion chromatography, and principle component analysis was employed for source apportionment. The results showed that the mass concentration of PM was 150.

Beneficial influences of pelelith and dicyandiamide on gaseous emissions and the fungal community during sewage sludge composting.

Reducing the emissions of NH and greenhouse gases (GHGs) during composting is essential for improving compost quality and controlling environmental pollution. This paper investigates the effects of pelelith (P) combined with dicyandiamide (DCD) on gaseous emissions and the fungal community diversity during sewage sludge (SS) composting. Results showed that the P and P + DCD treatments decreased the cumulative gaseous emissions by 41% and 22% for NH, 21% and 34% for NO, and 31.

Insights into aggregation and transport of graphene oxide in aqueous and saturated porous media: Complex effects of cations with different molecular weight fractionated natural organic matter.

The stability of nanomaterials in aquatic environment is a critical factor that governs their fate and ecotoxicity. Meanwhile, the interaction between nanomaterials and ubiquitous natural organic matter (NOM) is a vital process that influences the transport and biological effects of nanomaterials in the environment. However, impacts of NOM on the aggregation and transport of two-dimensional nanomaterials, especially for the increasingly used graphene oxide (GO), are not well understood.

Evaluation of total greenhouse gas emissions during sewage sludge composting by the different dicyandiamide added forms: Mixing, surface broadcasting, and their combination.

The aim of this work was to compare the impact of different adding forms of dicyandiamide (DCD) on NH and greenhouse gas (GHG) emissions during sewage sludge (SS) composting. Four treatments were set up using SS mixed with sawdust, to which DCD was then added by mixing (M), surface broadcasting (B), and a combination of the two (M+B). The treatment without DCD applied was used as the control.

A novel method for sewage sludge composting using bamboo charcoal as a separating material.

Traditional composting processes must be conducted with a bulking agent to ensure adequate air space for aeration. The bulking agent and composting materials are always completely mixed. A novel layered structure was introduced in sewage sludge composting, in which no bulking agent was used and bamboo charcoal was used as a separating material.

Studies on thermokinetic of Chlorella pyrenoidosa devolatilization via different models.

The thermokinetics of Chlorella pyrenoidosa (CP) devolatilization were investigated based on iso-conversional model and different distributed activation energy models (DAEM). Iso-conversional process result showed that CP devolatilization roughly followed a single-step with mechanism function of f(α)=(1-α), and kinetic parameters pair of E=180.5kJ/mol and A=1.

Usage of pumice as bulking agent in sewage sludge composting.

In this study, the impacts of reused and sucrose-decorated pumice as bulking agents on the composting of sewage sludge were evaluated in the lab-scale reactor. The variations of temperature, pH, NH3 and CO2 emission rate, moisture content (MC), volatile solid, dissolved organic carbon, C/N and the water absorption characteristics of pumice were detected during the 25days composting. The MC of pumice achieved 65.

Nitrogen transformations and losses during composting of sewage sludge with acidified sawdust in a laboratory reactor.

Composting is one of the cost-saving ways for sewage sludge treatment to produce a final product that is stable, and free of pathogens and plant seeds. However, the loss of nitrogen through ammonia emission not only reduces the agronomic value of the composting product, but also leads to air pollution and is potentially health threatening. Five mixtures of sewage sludge and acidified sawdust were co-composted for 22 days with different initial pH values (3.