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Adam Brady – Trace Organic Compound Removal in a Saturated Woodchip Bioreactor under Varying Sulfate

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My name is adam brady and i’m going to discuss the work of my co-authors and i on influent geochemistry and hydraulic resonance influences on microbial respiration and trace organic attenuation within saturated wood chip bioreactors widget bioreactors are created using lignocellulose substrates as geomedia and have been proven in treating agricultural runoff

Mining impaired waters and storm water they’re a passive treatment system that can be used outside of areas with centralized infrastructure services there has been limited investigation focused on the impact of residence time on redox conditions within saturated woodship bioreactors additionally there has been limited investigation on impact of redox conditions on

Trace organic removal outside of wastewater treatment plants or riverbank filtration we hypothesized that the redox conditions within the system manipulated through nitrate concentration and hydraulic resonance time would create environments more conducive to the removal of specific trace organic compounds providing an opportunity to understand the potential for

Saturated wood chip bioreactors as a standalone technology to assess the potential of a saturated widget bioreactor to remove trace organic compounds under nitrate and sulfate reducing conditions a system of eight upflow columns and four different redox conditions were evaluated the trace organics used are commonly found in wastewater treatment plant effluent

And the water is receiving it the columns were packed with 12 grams of substrate and were operated for 54 days the substrate included alfalfa hay and ground pine chips to support temporal sampling three mesh bags containing one gram of substrate with the same ratio and substrate as the columns were placed side by side in the column top each column received 100

Milligrams per liter sulfate and a varying nitrate concentration as nitrogen the concentration varied from zero milligrams per liter is nitrogen to 10 20 and 40. what you’re seeing here are effluent geochemistry across all four sets of duplicate columns and at both hrts of note you’ll see a dashed red line where the hrt was transitioned from 12 hours to 24 hours

In each panel the zero milligrams per liter columns received no nitrogen as seen in panel a while effluent aqueous sulfide concentrations increased as the hrt increased the 10 milligrams per liter columns completed nitric reduction somewhere in the columns of both hrts as seen here in panel b however the columns only transition to sulfate reduction at the longer

Hrt the effluent nitrogen species in the 20 milligrams per liter column seen in panel c and the 40 milligrams per liter columns seen in panel d provide evidence for nitrate reducing conditions primarily or predominantly occurring within the system through both hrts though the percent removed increased as the hrt increased neither set of columns exhibited sulfate

Reduction at any point during the experiment microbial samples were binned based on the presence of effluent aqueous sulfide in panel a the phylogenetic differences between the biogenetic distances between the redox conditions suggests an impact on microbial ecology due to those redox conditions within the column within the columns show a significant difference

Between 0 to 10 milligrams per liter in blue and the 20 to 40 milligram per liter samples in red the observed number of asvs in the sulfate reducing columns once again 0 to 10 milligrams per liter seen here in blue is significantly different from the 20 to 40 milligrams per liter or the nitrate reducing columns seen here in red supporting the assertion panel c

Shows the nitrate gradient within the columns created a very compelling gradient for the nitrite reductase nur s which is used as a proxy for nitrate reduction within each column type providing another piece of evidence suggesting varying redox conditions within the columns here we’re comparing trace organic attenuation for the three compounds that were attenuated

As well as a representative recalcitrant compound a tennoal in panel a underwent the largest transformation in the nitrate reducing conditions found in 20 milligrams per liter seen here in the dark green and 40 milligrams per liter seen in the yellow trimethoprim which can be seen in panel b demonstrated the largest removal in sulfate reducing conditions seen

Here in blue in the zero milligrams per liter column which is blue and in the 10 milligrams per liter column only during the longer hrt seen here in green sulfamethoxazole down in panel c demonstrated similar readout or similar removal across all redox conditions increasing only as hrt was increased and panel d shows carbamazepine which is used as a recalcitrant

Compound that demonstrates limited removal in any redox condition or hrt extending the hrt impacted the redox conditions within the constraints created by the implement geochemistry in the 0 20 and 40 milligrams per liter nitrate columns the prevalent redox condition was exacerbated in the 10 milligram per liter column the redox conditions transitioned from

Predominantly nitrate reducing to sulfate reducing only when the hrt was expanded as we will see with trucks removal the shift in redox conditions resulted in increased removal of some trace organics a tennowol has been previously shown to be susceptible to biotransformation in open water wetlands and stream biofilms the data in our investigation suggests that

Biotransformation of atenolol would be highest with increased nitrate reducing conditions created by increased nitrate concentrations and an increased hrt this finding indicates that compounds may transform most which undergo rapid biotransformation under oxic conditions may transform more slowly when sulfate reduction is predominant such that the removal of

These compounds should be targeted in systems that are also designed to treat nitrate this investigation suggested that trimethoprim may be more susceptible to enzymes and metabolic processes happening under sulfate-reducing conditions compared to nitrate-reducing conditions given the trimethylamine removal increased that sulfate reducing conditions increased

The data suggests that saturated wood should buy reactors could be used to augment a passive treatment system making the overall system more efficient with respect to tremendo prim removal our investigation suggests that hrt can be used as a design parameter within which you buy reactors to impact the overall removal of sulfur methoxazole without regard to the

Nitrate or sulfate reducing conditions found within the system given that the removal of sulfamethoxazole is still less than 25 percent within the conditions of the experiment other removal methods may be needed based on the priority of sulfamethoxazole removal within a treatment train as we demonstrated showing carbomazepine there were three compounds that

Were not removed appreciably during the experiment carbamazepine is known to be very recalcitrant and future research is needed to determine if there are geochemical conditions or a corresponding hrt within a saturated witcher bioreactor that may support its removal m tricidabean uh the lack of removal is similar to other studies that have shown intracitabine is

Biotransformed slowly suggesting that our hrts may not have been long enough for removal to be seen and the lack of removal of metaprolol suggests that other unit processes must be added to which widget bioreactors if metaprolol is of concern within a source water so in conclusion we determined that in allowing diverse redox conditions to occur by design based

On source water composition a saturated wood ship bioreactor may increase the removal effectiveness of certain trace organic compounds the manipulation of hrt demonstrates the opportunity to use resonance time as a design factor for desired performance objectives and saturated wood chip bioreactors demonstrate the potential to be used as a standalone technology

Or as a unit process inside a larger treatment train this investigation was a in collaboration with michael vega angela steegler dr rachel scholes and dr david sethlack at uc berkeley and mines undergraduate research assistants kim riddle and henry peel along with dr josh sharp this work was supported by the nsf nsf-funded erc for renew reinventing the nation’s

Urban water infrastructure or renew it a grant from the colorado higher education competitive research authority checker and the national institutes of water research additional support was provided by the us army’s advanced civil schooling program and the department of geo geography and environmental engineering at the united states military academy thank you

For your time and i look forward to your questions

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Adam Brady – Trace Organic Compound Removal in a Saturated Woodchip Bioreactor under Varying Sulfate By Mines GRADS