Lck 303

Concentrations of TN, NH₄⁺-N, PO₄³⁻-P and COD were determined in the SBW before and after treatment when the fungal biomass had been removed from the SBW by filtration. All SBW samples were frozen until analysis. Concentration of TN was determined with Hach Lange LCK 338 (ISO 1997 ) and the concentration of NH₄⁺-N was determined with Hach Lange LCK 303 (ISO 1984 ). Phosphate-phosphorus was determined with Hach Lange LCK 350 (ISO 2004 ). In order to study the effect of the treatments on organic carbon, COD was determined using Hach Lange LCK 014 (ISO 1989 ).

COD was measured according to DIN 38409-H41-H44, using the cuvette tests LCK 314, LCK 514 or LCK 614 (Hach, Düsseldorf, Germany), depending on expected COD concentration. P_tot was measured with LCK 350 cuvette tests (Hach, Düsseldorf, Germany), according to DIN EN ISO 6878-1-1986 and NH₄-N according to DIN 38406 E5-1, using LCK 303 cuvette tests. TOC was measured according to DIN EN1484 with a DIMATOC 2000 (DIMATEC, Essen, Germany).
Turbidity was measured according to DIN ISO 7027 with a Hach turbidimeter 2100 P ISO (Lange, Düsseldorf, Germany). TSS were determined according to the standard method DIN 38409-2. A Multi 3430 (WTW, Weilheim, Germany) was used for electrochemical analyses (pH, T, EC, and redox potential). A SenTix 980 probe was used for pH and temperature measurements, while a TetraCon 925 was used to determine the electrical conductivity and a SenTix ORP-T 900 probe for redox potential (WTW, Weilheim, Germany).

In addition to FIA, the sample concentrations of NO₃^‐ and NH₄⁺ were validated using portable colorimetric assays. For NH₄⁺ detection, the commercial LCK 303 (HACH LANGE GMBH, Germany) was used as follows; the cap zip of the commercial tube was unscrewed and carefully removed the foil from the screwed‐on cap zip. Then, 0.2 mL of sample was pipetted into the tube and the cap was immediately screwed back by fluting at the top. After that, the tube was shaken two to three times and left at room temperature for 15 min. Finally, the outside of the tube was cleaned with paper and placed into the reader. The method offered linearity in the range of 2.5‐60.0 mg/L. For NO₃^‐ detection, Palintest photometer 7100 (PHOT.23. AUTO) was used. Briefly, the Nitratest tube was filled until 20.0 mL mark. One leveled spoon of Nitratest powder and one Nitratest tablet was added and the tube was shaken for 1 min and left for 5 min or longer to ensure complete settlement of powders and to obtain a clear solution. The latter was carefully decanted into a round test tube and filled to 10.0 mL mark of tube. One Nitricol tablet was crushed and dissolved in 10.0 mL of clear solution. The tube was left for 10.0 min for the color to fully develop. Finally, the tube was placed into the detector. The method allowed linearity over a range of 0‐20 mg/L of NO₃^‐.

Total nitrogen (TN) measurements were performed on an N/Protein Analyzer (Flash EA 1112 Series, Thermo Electron S.p.A., Rodano, Italy), equipped with a carbon trap (soda lime), water trap (silica gel), catalysts of CuO and Pt/Al₂O₃, a separation column of Teflon and activated carbon, and a thermal conductivity detector (TCD). Dried samples were used per established TS protocols. In the analytical equipment, on dynamic flash combustion (Dumas method) of the samples, nitrogen compounds are released and reduced to nitrogen gas [25 ]. The analysis was performed at 900 °C, with helium as the carrier gas and oxygen gas was used for the combustion. Aspartic acid was used as the calibration standard.
The nitrogen salts that were analyzed included ammonia, nitrite, and nitrate. Spectrophotometry-based cuvette tests LCK 303, LCK 342 and LCK 340 (Hach Lange GmbH, Düsseldorf, Germany) were used to measure ammonia, nitrite, and nitrate, respectively. All cuvettes were analyzed on a DR2800 spectrophotometer (Hach Lange GmbH, Düsseldorf, Germany).

Aliquots (∼13 mL) were taken with a syringe through a needle permanently installed in the glass lid of the reactor. After the total COD was analyzed, the samples were filtered with glassfiber filters (0.45 μm, Chromafil GF/PET, Macherey-Nagel, Düren, Germany). Chloride, phosphate, sulfate, nitrite, and nitrate were analyzed by ion chromatography (881 compact IC pro, Metrohm, Herisau, Switzerland). Ammonia and total COD were measured photometrically with cuvette tests (LCK 303 and LCK 314/614, Hach Lange, Berlin, Germany). The total inorganic carbon was measured once with a total inorganic/total organic carbon analyzer (TOC-L, Shimadzu, Kyoto, Japan) according to manufacturers' protocol in a sample directly taken from the women's storage tank. The standard deviations of the wet chemical analyses were less than 5%.

The chemical composition of soil leachates was determined after the first and last cementation treatments, and after rewetting of soil columns. pH, total organic carbon (TOC), total nitrogen (TN), urea, ammonium, nitrite, nitrate and elements Ca, Na, Mg, K, Mn, Fe, Al, Ti, Si, B, Ba, Cd, Co, Cr, Cu, Mo, Ni, P, S, Se, Sr, V, W, and Zn in solution were determined. Liquid samples were centrifuged for 10 min and the supernatant analysed for TOC and TN (TOC-L Analyser with TNM-L unit, Shimadzu Ltd., United Kingdom) and elements determined by inductively coupled plasma optical emission spectroscopy (IC-OES, Perkin Elmer Avio 500) (James Hutton Ltd., Craigiebuckler, Aberdeen, United Kingdom). For ICP-OES analysis, samples obtained after rewetting of soil columns were pre-treated with a hot acid digest as the presence of amorphous calcium carbonate (ACC) was suspected, all other samples were diluted into a nitric acid matrix. Urea [r² = 0.999, SD_max = 0.04 mM; Knorst et al. (1997) (link)], ammonium, nitrate and nitrite (cuvette tests LCK303, LCK339 and LCK341, Hach Lange GmbH) were determined colourimetrically in triplicate by spectrophotometer (DR 5000^TM UV-Vis Spectrophotometer, United States).