Track topics on Twitter Track topics that are important to you
Nitrogen (N) removal in conventional bioretention systems is highly variable owing to the low nitrate (NO) elimination efficiency. We hypothesized that amending bioretention cells with biochar and zero-valent iron (ZVI) could improve the NO removal performance. A well-instrumented, bi-layer pilot-scale bioretention cell was developed to test the hypothesis by investigating its hydrologic performance and NO removal efficacy as affected by biochar and ZVI amendments. The cell containing 18% (v/v) wood biochar in the vadose zone and 10% (v/v) ZVI in the saturation zone was monitored for 18 months of field infiltration tests using synthetic stormwater amended with bromide (tracer) and NO. Compared to the Control cell without amendments, the Biochar/ZVI cell increased water retention by 11-27% and mean residence time by 0.7-3.8 h. The vadose zone of the Biochar/ZVI cell removed 30.6-95.7% (0.6-12.7 g) of NO-N from the influent, as compared with -6.1-89.6% (-0.1-2.9 g) by that of the Control cell. While the performance varied with synthetic storm events and seasons, in all cases the Biochar/ZVI cell resulted in greater NO removal than the Control cell. This improvement was presumably due to biochar's ability to improve water retention, facilitate anoxic conditions, increase residence time, and provide electrons for microbial denitrification. The saturation zone with ZVI amendment further promoted NO removal: removal was 1.8 times greater relative to the control in the first infiltration test, but was minimal in following tests. The reduction in performance of the ZVI amendment in subsequent tests might be due to diminished NO-N input to the saturation zone after treatment by the biochar-amended vadose zone. The redox potential and dissolved oxygen content at the vadose/saturation zone interface also indicated more favorable denitrification conditions in the Biochar/ZVI cell. Biochar amendment demonstrated significant promise for increasing nitrate removal in bioretention systems.
This article was published in the following journal.
Name: Water research
Bioretention is one of the most popular technical practices for urban runoff pollution control. However, the efficiency of nutrient removal from urban stormwater runoff by bioretention systems varies ...
This work studied the influence of pyrolysis temperature on the energy and mass balance of pyrolysis of rice husk (RH), cotton stalk (CS) and fruit branch (FB) in a pilot-scale biomass pyrolytic poly-...
The objective of this study is to synthesize previous research findings from bioretention experiments and identify design features that lead to the best performance of bioretention pollutant removal w...
Increased global regulation and restrictions on the non-therapeutic use of antibiotics in the poultry industry means that there is a need to identify alternatives that prevent infection while still co...
In this study, novel biochar supported nano-scale zero-valent iron (biochar-CMC-nZVI) stabilized by carboxymethyl cellulose (CMC) was developed and used for the removal of hexavalent chromium (Cr(VI) ...
The purpose of this study is to collect preliminary data on retinal nerve fiber layer and ganglion cell layer damage in multiple sclerosis (MS) patients, using optical coherence tomography...
The primary objective of this study is to demonstrate the non-inferiority of the 2-layer compression system Kit Biflex® with regard of the 4-layer compression system PROFORE® in the trea...
The purpose of this study is to examine the frequency of postoperative complications depending on the number of suture layers in colo-colonic and ileo-colonic anastomoses Hypothesis: doubl...
This is a small-scale pilot clinical study of the Rapamycin-Eluting Coronary Stent System of Microport for the first time to assess the preliminary safety and feasibility used in the human...
This study evaluated the effect of removal of smear layer on the success of primary root canal treatment.Patients requiring primary root canal treatment in mature mandibular first and seco...
Small-scale tests of methods and procedures to be used on a larger scale if the pilot study demonstrates that these methods and procedures can work.
Synthetic material used for the treatment of burns and other conditions involving large-scale loss of skin. It often consists of an outer (epidermal) layer of silicone and an inner (dermal) layer of collagen and chondroitin 6-sulfate. The dermal layer elicits new growth and vascular invasion and the outer layer is later removed and replaced by a graft.
Nerve cells of the RETINA in the pathway of transmitting light signals to the CENTRAL NERVOUS SYSTEM. They include the outer layer of PHOTORECEPTOR CELLS, the intermediate layer of RETINAL BIPOLAR CELLS and AMACRINE CELLS, and the internal layer of RETINAL GANGLION CELLS.
The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).
A scale comprising 18 symptom constructs chosen to represent relatively independent dimensions of manifest psychopathology. The initial intended use was to provide more efficient assessment of treatment response in clinical psychopharmacology research; however, the scale was readily adapted to other uses. (From Hersen, M. and Bellack, A.S., Dictionary of Behavioral Assessment Techniques, p. 87)