TY - JOUR A1 - Vogel, Christian A1 - Krüger, Oliver A1 - Herzel, Hannes A1 - Amidani, L. A1 - Adam, Christian T1 - Chemical state of mercury and selenium in sewage sludge ash based P-fertilizers JF - Journal of Hazardous Materials N2 - Phosphorus-fertilizers from secondary resources such as sewage sludge ash (SSA) will become more important in the future as they could substitute conventional fertilizers based on the nonrenewable resource phosphate rock. Thermochemical approaches were developed which remove heavy metals from SSA prior to its fertilizer application on farmlands. We analyzed the chemical state of mercury and selenium in SSA before and after thermochemical treatment under different conditions for P-fertilizer production by X-ray absorption near edge structure (XANES) spectroscopy. In some incineration plants the mercury loaded carbon adsorber from off-gas cleaning was collected together with the SSA for waste disposal. SSAs from those plants contained mercury mainly bound to carbon/organic material. The other SSAs contained inorganic mercury compounds which are most probably stabilized in the SSA matrix and were thus not evaporated during incineration. During thermochemical treatment, carbon-bound mercury was removed quantitatively. In contrast, a certain immobile fraction of inorganic mercury compounds remained in thermochemically treated SSA, which were not clearly identified. HgSe might be one of the inorganic compounds, which is supported by results of Se K-edge XANES spectroscopy. Furthermore, the chemical state of selenium in the SSAs was very sensitive to the conditions of the thermochemical treatment. KW - X-ray absorption near edge structure (XANES) spectroscopy KW - Phosphorus recovery KW - Sewage sludge ash KW - Mercury KW - Selenium KW - Mercury selenide (HgSe) PY - 2016 UR - http://dx.doi.org/10.1016/j.jhazmat.2016.03.079 DO - https://doi.org/10.1016/j.jhazmat.2016.03.079 VL - 313 SP - 179 EP - 184 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-35718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Rivard, C. A1 - Tanabe, I. A1 - Adam, Christian T1 - Microspectroscopy – promising techniques to characterize phosphorus in soil JF - COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS N2 - Phosphorus (P) is an essential element for all forms of life and is applied as fertilizer in agriculture. The P availability for plants may be highly dependent on the chemical state of P in fertilizers and soils; however, the nature of this dependence remains obscure due to the limitations of generally applied wet chemical and instrumental analytical approaches. This paper focuses on recently developed infrared, Raman, ultraviolet and X-ray microspectroscopic techniques for the characterization of P in soil. Microspectroscopic techniques have the advantage that discrete P phases can be distinguished and characterized even if their mass fractions are very low. However, only small volumes of soil can be analyzed by microspectroscopic methods hence a combination of macro- and microspectroscopic techniques is a promising concept. KW - Infrared KW - Microspectroscopy KW - Phosphorus KW - Raman KW - Soil KW - Ultraviolet KW - X-ray absorption near-edge structure (XANES) PY - 2016 DO - https://doi.org/10.1080/00103624.2016.1228942 SN - 0010-3624 SN - 1532-2416 VL - 47 IS - 18 SP - 2088 EP - 2102 AN - OPUS4-38341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hobohm, J. A1 - Kuchta, K. A1 - Krüger, Oliver A1 - van Wasen, Sebastian A1 - Adam, Christian T1 - Optimized elemental analysis of fluorescence lamp shredder waste JF - Talanta N2 - Fluorescence lamps contain considerable amounts of rare earth elements (REE). Several recycling procedures for REE recovery from spent lamps have been established. However, despite their economic importance, the respective recycling is scarce so far, with an REE recovery rate of less than 1%. A reliable analysis of REE and other relevant metals like Yttrium is crucial for a thorough and complete recovery process. This applies both to the solid matter and aqueous phase, since most of the recycling processes include wet-chemical steps. We tested seven different reagent mixtures for microwave-assisted digestion of fluorescent lamp shredder, including hydrofluoric acid, perchloric acid, and hydrogen peroxide. We determined the concentrations of 25 of the most relevant rare earth and other trace elements (Al, P, Ti, V, Cr, Fe, Ni, Cu, Ga, Ge, As, Y, Ag, Cd, Sn, Sb, La, Ce, Eu, Gd, Tb, W, Au, Hg, and Pb) in the respective dilutions. Two independent digestions, one a mixture of perchlorid/nitric/hydrofluoric acid and the other aqua regia, showed the highest concentrations of 23 of these elements, excluding only Sn and Tb. The REE concentrations in the tested lamp shredder sample (stated in g/kg) were 10.2 (Y), 12.1 (La), 7.77 (Ce), 6.91 (Eu), 1.90 (Gd), and 4.11 (Tb). KW - Yttrium KW - Rare earth elements KW - Elemental analysis KW - Microwave-assisted digestion PY - 2016 DO - https://doi.org/10.1016/j.talanta.2015.09.068 SN - 0039-9140 VL - 147 SP - 615 EP - 620 PB - Elsevier CY - Amsterdam AN - OPUS4-34992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Oliver A1 - Fattah, K. P. A1 - Adam, Christian T1 - Phosphorus recovery from the wastewater stream - necessity and possibilities JF - Desalination and Water Treatment N2 - The annual demand of phosphorus (P) for fertilizer use is more than 550,000 t in Germany. Several of the input streams like mineral fertilizer produced from phosphate rock or sewage sludge are problematic due to contamination with heavy metals and organic pollutants and/or supply risks. Phosphorus recovery from the wastewater stream might help to diminish these problems. Several procedures have been developed to recover P from either sewage sludge ash (SSA) or wastewater via precipitation or crystallization as struvite. This study determined the elemental composition and trace metal mass fractions of 252 SSA samples and 17 struvite samples from wastewater treatment plants (WWTP) to see whether there are differences related to the source of the sludge (municipal/industrial) or the stage of the WWTP where the struvite is produced. Results indicated that there is no clear trend of the elemental mass fractions related to the source of the sludge. All struvite samples show very low heavy metal contents, even though the struvite precipitated from the sludge shows slightly elevated heavy metal mass fractions compared to struvite crystallized from sludge liquor. Struvite is a clean and plant available material for fertilizer production from wastewater streams and has some advantages for the wastewater treatment plant. However, since the P recovery rate of struvite processes is low (7–11%) compared to that from SSA processes (90%), recovery from SSA is necessary for a substantial P recovery from the wastewater stream. T2 - 3rd International Conference on Water, Energy and Environment (ICWEE) CY - Sharjah, United Arab Emirates DA - 24.03.2015 KW - Struvite KW - Phosphorus recovery KW - Wastewater KW - Sewage sludge ash PY - 2016 DO - https://doi.org/10.1080/19443994.2015.1103315 SN - 1944-3994 SN - 1944-3986 VL - 57 IS - 33 SP - 15619 EP - 15627 PB - Taylor & Francis CY - Philadelphia, USA AN - OPUS4-36260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herzel, Hannes A1 - Krüger, Oliver A1 - Hermann, L. A1 - Adam, Christian T1 - Sewage sludge ash - A promising secondary phosphorus source for fertilizer production JF - Science of the total environment N2 - Sewage sludge incineration is extensively practiced in some European countries such as the Netherlands, Switzerland, Austria and Germany. A survey of German sewage sludge ash showed that the recovery potential is high, approx. 19,000 t of phosphorus per year. However, the survey also discovered that the bioavailability of phosphorus in the sewage sludge ash is poor and that more than half of the ashes cannot be used as fertilizers due to high heavy metal content. A new thermochemical process for sewage sludge ash treatment was developed that transforms the ash into marketable fertilizer products. Sewage sludge ash was thermochemically treated with sodium and potassium additives under reducing conditions, whereby the phosphate-bearing mineral phases were transformed into plant available phosphates. High P-bioavailability was achieved with a molar Na/P ratio > 1.75 in the starting materials. Sodium sulfate, carbonate and hydroxide performed comparably as additives for this calcination process. Potassium carbonate and -hydroxide have to be added in a molar K/P ratio > 2.5 to achieve comparable P-solubility. The findings of the laboratory scale investigations were confirmed by an industrial demonstration trial for an ash treatment with sodium sulfate. Simultaneously, the volatile transition metal arsenic (61% removal) as well as volatile heavy metals such as cadmium (80%), mercury (68%), lead (39%) and zinc (9%) were removed via the off-gas treatment system. The product of the demonstration trial is characterized by high bioavailability and a toxic trace element mass fraction below the limit values of the German fertilizer ordinance, thus fulfilling the quality parameters for a P-fertilizer. KW - Sewage sludge ash KW - Phosphorus recovery KW - Thermochemical treatment KW - Reducing conditions KW - Heavy metal evaporation KW - Bioavailability KW - Sodium sulfate PY - 2016 DO - https://doi.org/10.1016/j.scitotenv.2015.08.059 SN - 0048-9697 SN - 1879-1026 IS - 542 SP - 1136 EP - 1143 PB - Elsevier CY - Amsterdam AN - OPUS4-34165 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Krüger, Oliver A1 - Adam, Christian T1 - Thermochemical treatment of sewage sludge ash with sodium additives under reducing conditions analyzed by thermogravimetry JF - Journal of thermal analysis and calorimetry N2 - Phosphorus (P) for fertilizer use can be recovered from sewage sludge ash (SSA). To enhance the bioavailability of P and reduce the heavy metal content of SSA, it can be treated thermochemically with Na2CO3 or Na2SO4 at 950 °C in a rotary kiln using dry sewage sludge or lignite as reducing agent. These processes were investigated by thermogravimetry/differential thermal analysis coupled with gas analysis. Reducing conditions in this experimental setup were provided by 2 % hydrogen in the Ar carrier gas. During SSA + Na2CO3 treatment CO2, CO and water were detected in the off-gas. During SSA + Na2SO4 treatment SO2, some CO2 and water were detected. Heavy metal removal was more efficient for SSA + Na2CO3 compared to the sulfate variant. A SSA + Na2SO4 + lignite variant which also formed CO shifted the heavy metal removal to the results obtained with Na2CO3 which was obviously due to the additional reduction potential. However, Zn evaporation was not achieved with the Na2SO4 variants which were most probably due to immobilization as ZnS. KW - Phosphorus recovery KW - Thermochemical treatment KW - Sewage sludge ash KW - Reducing conditions KW - Heavy metal evaporation KW - FT-IR gas analysis PY - 2016 DO - https://doi.org/10.1007/s10973-015-5016-z SN - 1388-6150 SN - 1418-2874 SN - 0368-4466 SN - 1572-8943 VL - 123 IS - 2 SP - 1045 EP - 1051 PB - Springer CY - Dordrecht AN - OPUS4-34556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -