Supporting constructed wetlands in P removal efficiency from surface water

The research investigated the implementation of suspended reactive filters to support the phosphorus (P) removal efficiency of constructed wetlands (CWs). The reactive material (RM) used in this study was autoclaved aerated concrete (AAC). The laboratory experiment consists of four plastic boxes filled with the volume of 10 L of artificial P solution with three variants of RM mass to volume ratio: 1:1 (g:L), 5:1 (g:L), 10:1 (g:L), and the blind probe 0:1 (g:L) as a reference. AAC of different weights (10, 50 and 100 g) was wrapped in a filter bag, put into boxes, and suspended. After 30 days of the laboratory experiment, AAC was able to reduce the P-PO4 concentration from 2.972 mg·L−1 to: 0.341 mgPO4-P·L−1, 0.006 mgPO4-P·L−1 and 0.004 mgPO4-P·L−1 for 10 g, 50 g and 100 g mass variant, respectively. This concentration reduction corresponds to unit sorption of: 2.53 mgP-PO4·g−1, 0.58 mgP-PO4·g−1 and 0.30 mgP-PO4·g−1 for 10 g, 50 g and 100 g, respectively. Based on the obtained data, the CW supporting filter was dimensioned to reduce the outflow P concentration to 0.01 mg·L−1. P removal efficiency prediction was calculated for Cetynia River, Poland.

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Upgrading constructed wetlands phosphorus reduction from a dairy effluent using electric arc furnace steel slag filters

Water Science & Technology ◽

10.2166/wst.2007.513 ◽

2007 ◽

Vol 56 (3) ◽

pp. 135-143 ◽

Cited By ~ 35

Author(s):

D. Weber ◽

A. Drizo ◽

E. Twohig ◽

S. Bird ◽

D. Ross

Keyword(s):

Removal Efficiency ◽

Constructed Wetlands ◽

Steel Slag ◽

Dairy Farm ◽

Electric Arc Furnace ◽

Electric Arc ◽

Management Approach ◽

Arc Furnace ◽

Treated Water ◽

P Removal

In 2003, a subsurface flow constructed wetlands (SSF-CW) system was built at the University of Vermont (UVM) Paul Miller Dairy Farm as an alternative nutrient management approach for treating barnyard runoff and milk parlour waste. Given the increasing problem of phosphorus (P) pollution in the Lake Champlain region, a slag based P-removal filter technology (PFT) was established (2004) at the CW with two objectives: (i) to test the filters' efficiency as an upgrade unit for improving P removal performance via SSF-CW (ii) to investigate the capacity of filters technology to remove P as a “stand alone” unit. Six individual filters (F1–F6) were filled with electric arc furnace (EAF) steel slag, each containing 112.5 kg of material with a pore volume of 21 L. F1–F4, fed with CW treated water, received approximately 2.17 g DRP kg−1 EAF steel slag (0.25 kg DRP total) during the 259 day feeding period. F1–F4 retained 1.7 g DRP kg−1 EAF steel slag, resulting in an average P removal efficiency of 75%. The addition of filters improved CW DRP removal efficiency by 74%. F5 and F6, fed non-treated water, received 1.9 g DRP kg−1 EAF steel slag (0.22 kg DRP in total) and retained 1.5 g DRP kg−1 resulting in a P removal efficiency of 72%. The establishment of the EAF slag based PFT is the first in-field evaluation of this technology to reduce P from dairy farm effluent in Vermont.

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P1401THE REMOVAL EFFICIENCY OF PHOSPHATE FROM INTRACELLULAR FLUID DURING HEMODIALYSIS

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfaa142.p1401 ◽

2020 ◽

Vol 35 (Supplement_3) ◽

Author(s):

Hiroshi Kikuchi ◽

Hisaki Shimada ◽

Ryo Karasawa ◽

Masashi Suzuki

Keyword(s):

Regression Analysis ◽

Removal Efficiency ◽

Extracellular Fluid ◽

Residual Renal Function ◽

Intracellular Fluid ◽

Positive Correlation ◽

P Concentration ◽

Exchange Resins ◽

Total P ◽

P Removal

Abstract Background and Aims In hemodialysis (HD) patients without residual renal function, almost all of phosphate (P) absorbed through intestine is eliminated with HD. To avoid hyperphosphatemia, which is major risk for mortality in HD patients, reduced P absorption and /or improved P removal efficiency should be required. The P elimination during HD from intracellular fluid (ICF) remarkably differs from that from extracellular fluid (ECF). Because the total P removal is too complicate to analyze, few studies about P removal efficiency have been performed. In this study, we tried to separately estimate the amount of P removal from ICF and ECF. Method Fifty-eight patients undergoing 4-hour HD with BMI 22±3 were enrolled this study. ECF and ICF volumes were considered respectively as 20% and 40% of body weight (BW). The amount of urea nitrogen (UN) removal (Run) was calculated using the values of serum UN concentration (UN0, UN4) and total body fluid (60% of BW) at pre and post HD as 0.6(UN0 x pre BW – UN4 x post BW). The amount of intradialytic total P removal (Rp) was calculated using the formula previously reported. At starting phase of HD, P is considered to be removed only from ECF, and from ECF and ICF at later stage. In initial hours, when P is removed only from ECF, serum P concentration change exponentially (P = KptP0) as serum UN concentration (UN = KuntUN0). (Where, Kun and Kp are exponential coefficient of UN and P respectively, t is time (min), P0 is serum P concentration before HD). If P outflow from ICF is disregarded, the exponential change in P persists, and serum P concentration at the end of 4-hour HD is Kp240P0. Consequently, the amount of P removal from ECF (Rp(ex)) was calculated as 0.2(P0 x preBW - Kp240P0 x postBW). The exponential coefficient in P change was reported to be 0.997788 times of that in UN. The amount of P removal from ICF (Rp(in)) was calculated as difference between Rp and Rp(ex). Each removal efficiency was calculate as Run/UN0, Rp(ex)/P0 or Rp(in)/P0. Intradialytic removal of P from ECF and ICF were compared with that of UN. Regression analysis was performed on 24 factors which might affect the efficiency. The relationship between drug administration and the removal efficiency was investigated as for 22 drugs. Results UN removal and P removal from ECF were closely related. Run and Rp(ex) had positive correlation (0.564, p<0.001). And Run/UN0 also correlated positively to Rp(ex)/P0 (R=0.970, p<0.001). Rp(ex)/P0 and P0 had a positive correlation (R=0.334, p<0.01) as well as Run/UN0 and UN0 (R=0.382, p<0.01). P removal from ICF showed different pattern. In comparison between P removal from ECF and ICF, removal amount showed positive correlation (R=0.634, p<0.001), but removal efficiency showed no correlation(R=0.006, ns). Notably, Rp(in)/P0 and P0 had negative correlation (R=0.315, p<0.02). Rp(in) accounted for 44.6±6.2% of Rp. On regression analysis concerning the 24 factors, only P0 and its confounding factors showed correlation with Rp(ex), Rp(in), Rp(ex)/P0 or Rp(in)/P0. Rp(ex)/P0 or Rp(in)/P0 were not affected with administration of 22 investigated drugs. To exclude the influence of P0 on Rp(in)/P0, adjusted Rp(in)/P0 (removal efficiency of P from ICF not affected by P0) was calculated. Investigation on iron containing P binders and ion exchange resins revealed each drug groups ameliorated adjusted Rp(in)/P0. Conclusion This is the first report to analyze separately P removal from ECF and ICF during HD. Increased UN removal efficiency results in increased the removal efficiency of P from ECF, but did not improved that from ICF. Rp(in) accounts for about half of Rp. For improving total P removal efficiency, removal efficiency of P from ICF should be increased. Some drugs were suggested to increase removal efficiency of P from ICF.

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EFFICIENCY OF FERRIC SULPHATE FOR REMOVAL OF PHOSPHORUS FROM MEAT PROCESSING WASTEWATER

Proceedings of the 7th International Scientific Conference Rural Development 2015 ◽

10.15544/rd.2015.077 ◽

2015 ◽

Author(s):

Valerijus GASIŪNAS

Keyword(s):

Removal Efficiency ◽

Active Ingredient ◽

Phosphorus Removal ◽

Limiting Factors ◽

Aeration Tank ◽

Meat Processing ◽

Ferric Sulphate ◽

P Concentration ◽

Total P ◽

P Removal

Meat processing wastewater is heavily contaminated with phosphorus. It can be removed from wastewater by the use of flocculants. Phosphorus removal efficiency was estimated by treating wastewater with ferric sulphate flocculant, containing 11.5 percent of the active ingredient Fe3+ by weight. The research was conducted with wastewater pretreated in an aeration tank. Wastewater, containing 41.0 ± 3.5 mg l-1 of total phosphorus (TP), was dispensed into calibrated 1.0 liter containers with the following concentrations of flocculating agent: 0, 30, 75, 120, 150, 300, 450, 600, 750, 900 and 1,050 mg/l. The study showed that TP removal efficiency depends on the flocculant dose used for treatment. Increasing the flocculant dose decreases the efficiency of TP removal. One gram of Fe3+, given the flocculant dose of 40 gFe3+/m3, removed 0.5 g/m3 of TP, while 120 g/m3 of the flocculant removed around 40 percent less. According to the dependence of total P removed on the flocculant dose calculated by its active ingredient Fe3+, ferric sulphate flocculant is the most effective at doses of up to 60–80 g/m3 of Fe3+. The use of ferric sulphate may be limited by its impact on pH and sulphate concentrations in the effluent wastewater. If pH is not additionally adjusted, a maximum concentration of 70 g Fe3+/m3 can be used in order to maintain the pH of wastewater above 6.5 and to keep final sulphate concentration below 300 mg/l. In summary, a maximum of 70 g Fe3+/m3 can be used based on the total P removal efficiency and limiting factors. Such dose could remove 28 g total P/m3 from the wastewater. Since the permissible total P concentration in effluent wastewater is 4.0 mg/l, it is reasonable to use the ferric sulphate flocculant, containing 11.5 % of Fe3+ as an active ingredient, for treating wastewater with an initial total P concentration of up to 32 mg/l.

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Crushed Autoclaved Aerated Concrete (CAAC), a Potential Reactive Filter Medium for Enhancing Phosphorus Removal in Nature-Based Solutions—Preliminary Batch Studies

Water ◽

10.3390/w11071442 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1442

Author(s):

Castellar ◽

Formosa ◽

Chimenos ◽

Canals ◽

Bosch ◽

...

Keyword(s):

Chemical Characterization ◽

Limited Resource ◽

Filter Medium ◽

Batch Studies ◽

Autoclaved Aerated Concrete ◽

Aerated Concrete ◽

Physical And Chemical ◽

Main Effects ◽

P Removal

Phosphorus (P) is a limited resource and can promote eutrophication of water streams and acidification of oceans when discharged. Crushed autoclaved aerated concrete (CAAC), a by-product from demolition, has shown great potential for recovering P. The potential of CAAC to be used in nature-based solutions as a P-reactive filter medium was evaluated by performing preliminary batch essays. Here, we evaluated the interactions and main effects of the initial concentration of P (Pi; 5, 10 or 20 mg L−1), particle size (PS; 4 or 5 mm) and contact time (CT; 60, 180, 360, 720 and 1440 min) upon the removal. We performed physical and chemical characterization to understand the removal processes. Data collected were fitted in adsorption kinetic models. The statistical analysis showed a significant interaction between CT and Pi, with the combination of its main effects stronger on P removal than each one separately. Intriguingly, we noticed that the higher the concentration of Pi, the faster and higher the removal of P. Contrary to expectations, PS 5 mm showed higher removal rates than PS 4 mm, indicating that besides adsorption, other unidentified chemical processes are in place. Further studies using columns/pilots with real wastewater are recommended for a future follow-up.

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