Effect of pyrolysis on the removal of antibiotic resistance genes and class I integrons from municipal wastewater biosolids

Kimbell, Lee K.; Kappell, Anthony D.; McNamara, Patrick J.

doi:10.1039/c8ew00141c

Cited by 28 publications

(21 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…34 Coefficient of determination in the linear regression of the standard curves were greater than 0.99, consistent with the designed assay. 34 The qPCR limit of quantification for ARGs and related genes was 5 copy numbers (CNs), which was equivalent to 5 × 10 4 CN L −1 for final filtrate and 5 × 10 5 CN L −1 for samples taken at primary influent feed, FBR effluent, and membrane feed ( Fig. 1) based upon the volume of sample, resuspension volume following DNA extraction, and volume of DNA used in PCR.…”

Section: Methodssupporting

confidence: 79%

Removal of antibiotic resistance genes in an anaerobic membrane bioreactor treating primary clarifier effluent at 20 °C

Kappell

Kimbell

Seib

et al. 2018

Environ. Sci.: Water Res. Technol.

Self Cite

View full text Add to dashboard Cite

Anaerobic membrane bioreactors (AnMBR) play a key role in future plans for sustainable wastewater treatment and resource recovery because they have no energy-intensive oxygen transfer requirements and can produce biomethane for renewable energy. Recent research results show that they can meet relatively stringent discharge limits with respect to BOD 5 and TSS when treating municipal wastewater primary effluent. Sustainable used water recovery plans should also consider removal of unregulated pollutants. Antibiotic resistance genes (ARGs) represent an important emerging contaminant due to public health concerns surrounding the spread of infections resistant to common antibiotics. Conventional activated sludge processes have demonstrated mixed results regarding ARG removal. The objective of this research was to determine the impact of an AnMBR on ARG removal when treating municipal primary clarifier effluent at 20°C. AnMBR treatment resulted in 3.3 to 3.6 log reduction of ARG and the horizontal gene transfer determinate, intI1, copies in filtrate. Membrane treatment significantly decreased the total biomass as indicated by a decrease in 16S rRNA gene concentration. Microbial community analysis via Illumina sequencing revealed that the relative abundance of putative pathogens was higher in membrane filtrate compared to primary effluent although the overall bacterial 16S rRNA gene concentrations was lower in filtrate. Membrane treatment also substantially reduced microbial diversity in filtrate compared to anaerobic reactor contents.Mainstream anaerobic wastewater treatment is a promising technology for sustainable water resource recovery. Anaerobic membrane bioreactors (AnMBRs) can meet relatively stringent BOD 5 and TSS regulatory standards (BOD 5 <10 mg L −1 , TSS <10 mg L −1 ) for municipal wastewater at temperatures as low as 10°C. The research reported herein demonstrated that AnMBR technology can also significantly reduce antibiotic resistance gene copies.

show abstract

Section: Methodssupporting

confidence: 79%

Removal of antibiotic resistance genes in an anaerobic membrane bioreactor treating primary clarifier effluent at 20 °C

Kappell

Kimbell

Seib

et al. 2018

Environ. Sci.: Water Res. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Contaminants such as antibiotic resistance genes, pathogens and other micropollutants can enter the environment when wastewater solids are land applied or landfilled [1,2]. Release of these constituents may be reduced if solids management technologies such as pyrolysis are employed to remove or destroy these contaminants and reduce the volume of biosolids [1,3,4]. Pyrolysis involves the thermal conversion of wastewater solids in the absence of oxygen at temperatures between 400 and 1000 • C, and yields three products: biochar, pyrolysis gas (py-gas) and pyrolysis liquid [5][6][7][8].…”

Section: Introductionmentioning

confidence: 99%

Inhibition during Anaerobic Co-Digestion of Aqueous Pyrolysis Liquid from Wastewater Solids and Synthetic Primary Sludge

et al. 2020

View full text Add to dashboard Cite

Pyrolysis can convert wastewater solids into useful byproducts such as pyrolysis gas (py-gas), bio-oil and biochar. However, pyrolysis also yields organic-rich aqueous pyrolysis liquid (APL), which presently has no beneficial use. Autocatalytic pyrolysis can beneficially increase py-gas production and eliminate bio-oil; however, APL is still generated. This study aimed to utilize APLs derived from conventional and autocatalytic wastewater solids pyrolysis as co-digestates to produce biomethane. Results showed that digester performance was not reduced when conventional APL was co-digested. Despite having a lower phenolics concentration, catalyzed APL inhibited methane production more than conventional APL and microbial community analysis revealed a concomitant reduction in acetoclastic Methanosaeta. Long-term (over 500-day) co-digestion of conventional APL with synthetic primary sludge was performed at different APL organic loading rates (OLRs). Acclimation resulted in a doubling of biomass tolerance to APL toxicity. However, at OLRs higher than 0.10 gCOD/Lr-d (COD = chemical oxygen demand, Lr = liter of reactor), methane production was inhibited. In conclusion, conventional APL COD was stoichiometrically converted to methane in quasi steady state, semi-continuous fed co-digesters at OLR ≤ 0.10 gCOD/Lr-d. Undetected organic compounds in the catalyzed APL ostensibly inhibited anaerobic digestion. Strategies such as use of specific acclimated inoculum, addition of biochar to the digester and pretreatment to remove toxicants may improve future APL digestion efforts.

show abstract

“…Py-gas and the nonaqueous phase of bio-oil can both be used as fuels after conditioning. Additionally, biosolids pyrolysis removes recalcitrant contaminants including triclosan and triclocarban, antibiotic resistance genes, as well as reduces total estrogenicity of the resulting biochar [19][20][21]. However, bio-oil from conventional slow pyrolysis of biosolids (biochar is the target product with heating rate below 100 • C/min, hereafter referred to as pyrolysis) normally accounts for at least 40% of the total product mass [17] and requires costly pretreatment due to its corrosive and unstable properties before it can be used as a clean fuel [22].…”

Section: Introductionmentioning

confidence: 99%

Sub-Pilot-Scale Autocatalytic Pyrolysis of Wastewater Biosolids for Enhanced Energy Recovery

2018

Self Cite

View full text Add to dashboard Cite

Improving onsite energy generation and recovering value-added products are common goals for sustainable used water reclamation. A new process called autocatalytic pyrolysis was developed at bench scale in our previous work by using biochar produced from the biosolids pyrolysis process itself as the catalyst to enhance energy recovery from wastewater biosolids. The large-scale investigation of this process was used to increase the technical readiness level. A sub-pilot-scale catalytic pyrolytic system was constructed for this scaled-up study. The effects of configuration changes in both pyrolytic and catalytic reactors were investigated as well as the effect of vapor-catalyst contact types (i.e., downstream, in-situ) on product yield and quality. The sub-pilot-scale test with downstream catalysis resulted in higher py-gas yields and lower bio-oil yields when compared to results from a previous batch, bench-scale process. In particular, the py-gas yields increased 2.5-fold and the energy contained in the py-gas approximately quadrupled compared to the control test without autocatalysis. Biochar addition to the feed biosolids before pyrolysis (in-situ catalysis) resulted in increased py-gas production, but the increase was limited. It was expected that using a higher input pyrolyzer with a better mixing condition would further improve the py-gas yield.

show abstract

Effect of pyrolysis on the removal of antibiotic resistance genes and class I integrons from municipal wastewater biosolids

Abstract: Biosolids carry a substantial portion of antibiotic resistance genes (ARGs) leaving wastewater treatment plants. Pyrolysis substantially reduces ARGs in biosolids.

Cited by 28 publications

References 71 publications

Removal of antibiotic resistance genes in an anaerobic membrane bioreactor treating primary clarifier effluent at 20 °C

Removal of antibiotic resistance genes in an anaerobic membrane bioreactor treating primary clarifier effluent at 20 °C

Inhibition during Anaerobic Co-Digestion of Aqueous Pyrolysis Liquid from Wastewater Solids and Synthetic Primary Sludge

Sub-Pilot-Scale Autocatalytic Pyrolysis of Wastewater Biosolids for Enhanced Energy Recovery

Contact Info

Product

Resources

About