TY - JOUR
A1 - Krüger, Oliver
A1 - Adam, Christian
T1 - Phosphorus in recycling fertilizers - analytical challenges
N2 - The importance of secondary raw materials for phosphorus (P) fertilizer production is expected to increase in the future due to resource depletion, supply risks, and heavy metal contamination of fossil phosphate resources. Municipal wastewater is a promising source for P recovery. In Germany for instance, it contains almost 50% of the total amount of P that is currently applied as mineral fertilizer. Several procedures have been developed to recover and re-use P resulting in a growing number of recycling fertilizers that are currently not regulated in terms of fertilizer efficiency. We tested various materials and matrices for their total P content, solubility of P in neutral ammonium citrate (Pnac) and water, and performed robustness tests to check if existing analytical methods are suitable for those new materials. Digestion with inverse aqua regia was best suited to determine the total P content. Pnac sample preparation and analyses were feasible for all matrices. However, we found significant time and temperature dependencies, especially for materials containing organic matter. Furthermore, several materials didn’t reach equilibrium during the extractions. Thus, strict compliance of the test conditions is strongly recommended to achieve comparable results.
KW - Recycling fertilizer
PY - 2017
DO - https://doi.org/10.1016/j.envres.2017.02.034
SN - 0013-9351
SN - 1096-0953
VL - 155
SP - 353
EP - 358
PB - Elsevier
CY - Rotterdam
AN - OPUS4-39430
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
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 - Peplinski, Burkhard
A1 - Adam, Christian
A1 - Michaelis, Matthias
A1 - Kley, Gerd
A1 - Emmerling, Franziska
A1 - Simon, Franz-Georg
T1 - Reaction sequences in the thermochemical treatment of sewage sludge ashes revealed by X-ray powder diffraction - A contribution to the European project SUSAN
N2 - The sequence of reactions accompanying the thermochemical treatment of an iron- and aluminium-bearing sewage sludge ash was ascertained by investigating two systematic series of samples. The ash was thermochemically treated in a lab-scale rotary furnace after mixing it with a chlorine-donor, either CaCl2 or MgCl2. Within each of these two sample series only a single process parameter, the reaction temperature, was varied, namely between 350 and 1050°C. It was found, that among the numerous crystalline phases present in the raw ash only quartz and hematite continue to exist after thermochemical treatments carried out at 1050°C, whereas all other components undergo at least one decomposition-recrystallization cycle. Some of the components re-crystallize even several times. It was proved that the restructuring of the calcium- and phosphorus-bearing mineral phases proceeds via the formation of chlorspodioside, Ca2PO4Cl. The influence of the type of chlorine-donor on the final product was elucidated in detail and - to the best of our knowledge - for the first time crystalline AlPO4 was found in a sewage sludge ash and its decomposition was investigated, too.
KW - XRD
KW - Phosphorus recovery
KW - Sewage sludge ash
KW - Urban mining
KW - Fertilizers
PY - 2009
DO - https://doi.org/10.1524/zksu.2009.0068
SN - 0930-486X
VL - 30 EPDIC 2008
SP - 459
EP - 464
PB - Oldenbourg
CY - München
AN - OPUS4-20562
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Auer, G.
A1 - Spanka, M.
A1 - Hamann, Christopher
A1 - Adam, Christian
T1 - Thermal zinc extraction from steel mill dust
N2 - Treatment and reusing of hazardous wastes have become significant issues of modern societies. Blast furnace sludge (BFS) and electric arc furnace dust (EAFD) are such typical wastes, because they usually contain high amounts of undesirable elements such as zinc (Zn) and lead (Pb).
These elements can cause operational problems in reusing of BFS and EAFD. In this study, the Ferro Duo GmbH and the Federal Institute for Materials Research and Testing have investigated a novel approach for eliminating and/or recovering Zn and Pb from both wastes. Applied was a selective chlorination and volatilization of Zn and Pb as chlorides at temperatures between 500 °C and 1100 °C. Both product obtained, Zn and Pb in the form of ZnCl2 and PbCl2 and the purified solid mineral compound are attractive materials for further use. Hydrochloric acid and iron(II) chloride were used as chlorination agents. Exceptionally high Zn and Pb removal efficiencies of >99.5 % could be achieved with both chlorination agents, whereby iron(II) chloride exhibited better performance.
KW - Blast furnace sludge
KW - Chlorination
KW - Electric arc furnace dust
KW - Lead
KW - Zinc
KW - Thermochemical treatment
PY - 2019
SN - 1613-2394
VL - 72
IS - 1
SP - 27
EP - 31
PB - GDMB Verlag GmbH
CY - Clausthal-Zellerfeld
AN - OPUS4-47288
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Walsh, Michael
A1 - Schenk, Gerhard
A1 - Robinson, Nicole
A1 - John, Samuel
A1 - Dayananda, Buddhi
A1 - Krishnan, Vithya
A1 - Adam, Christian
A1 - Hermann, Ludwig
A1 - Schmidt, Susanne
T1 - The Circular Phosphorus Economy: Agronomic Performance of Recycled Fertilizers and Target Crops
N2 - ABSTRACTBackgroundThe circular phosphorus (P) economy addresses economic and environmental penalties inherent to the current linear P economy. Phosphorus sources recovered from waste steams (recyclates) offer an alternative to conventional fertilizers.AimThis research aimed to assess the agronomic performance of P recyclates derived from wastewater (hazenite, struvite), treated sewage sludge ash (SSA) and compost (FOGO food organics/garden organics) with crops previously characterized for P use efficiency (PUE).MethodsPhosphorus was supplied as granules and benchmarked against conventional fertilizers or mineral solution. Grown in controlled conditions, crops received recyclates individually or as amalgamates, with or without additional water‐soluble P. We quantified P uptake, yield and phytate content, and calculated agronomic performance indicators.ResultsResults revealed that (1) crop genotypes with purportedly lower or higher PUE showed similar performance when grown with limiting P supply and/or less soluble P recyclates, (2) crop performance improved when less soluble P recyclates were combined with water‐soluble P, (3) crops produced similar yield and biomass when supplied with an organo‐mineral formulation, hazenite, or conventional fertilizer, (4) grain accumulated higher levels of the antinutrient phytate with excess soluble P.ConclusionWe conclude that suitably formulated P recyclates can supplement or replace conventional fertilizers, and that fertilizer design should consider the solubility of recyclates and a crop's ability to access less soluble P. This adds to the growing body of evidence that well‐formulated next‐generation fertilizers can efficiently nourish crops. Integrating insights from controlled experiments and field trials is a cost‐effective strategy to actualize the circular P economy.
KW - Recycling fertilizer
KW - Phosphate recovery
KW - Sewage sludge ash
KW - Struvite
KW - Hazenite
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-627116
DO - https://doi.org/10.1002/jpln.202400299
SP - 1
EP - 14
PB - Wiley
AN - OPUS4-62711
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hamann, Christopher
A1 - Spanka, M.
A1 - Stolle, Dirk
A1 - Auer, G.
A1 - Weingart, Eric
A1 - Al-Sabbagh, Dominik
A1 - Ostermann, Markus
A1 - Adam, Christian
T1 - Recycling of blast-furnace sludge by thermochemical treatment with spent iron(II) chloride solution from steel pickling
N2 - One of the typical wastes produced in blast-furnace (BF) ironmaking is BF sludge, which mostly consists of carbon and iron oxides, but also contains toxic trace metals such as Zn, Pb, Cd, As, and Hg that render the material hazardous. Due to the lack of an established recycling process, BF sludges are landfilled, which is ecologically questionable and costly. Here, we investigate selective removal of Zn, Pb, and Cd from BF sludge by chlorination–evaporation reactions using thermodynamic modelling and laboratory-scale experiments. Specifically, BF sludge was thermochemically treated at 650–1000 °C with a spent iron(II) chloride solution from steel pickling and the effects of process temperature and retention time on removal of Zn, Pb, and Cd were investigated. Zinc and Pb were quantitatively removed from BF sludge thermochemically treated at 900–1000 °C, whereas Fe and C as well as other major elements were mostly retained. The Zn, Pb, and Cd contents in the thermochemically treated BF sludge could be lowered from ∼56 g/kg, ∼4 g/kg, and ∼0.02 g/kg to ≤0.7 g/kg, ≤0.02 g/kg, and ≤0.008 g/kg, respectively, thus rendering the processed mineral residue a non-hazardous raw material that may be re-utilized in the blast furnace or on the sinter band.
KW - Blast-furnace sludge
KW - Selective chlorination
KW - Zinc chloride
PY - 2021
DO - https://doi.org/https://doi.org/10.1016/j.jhazmat.2020.123511
SN - 0304-3894
VL - 402
IS - 123511
SP - 1
EP - 12
PB - Elsevier
CY - Amsterdam
AN - OPUS4-51141
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Smol, M.
A1 - Adam, Christian
A1 - Krüger, O.
T1 - Use of nutrients from wastewater for the fertilizer industry - approaches towards the implementation of the circular economy (CE)
N2 - More sustainable waste management practices are an important element in the Transformation towards a circular economy (CE). Activities in this area should be dedicated to all groups of waste, including those generated in the water and sewage sector. This paper presents the characteristics of sewage sludge ash (SSA) coming from Polish municipal waste incineration plants. Due to the high content of nutrients such as phosphorus (8.01% P2O5), calcium (5.11% CaO) and magnesium (2.75% MgO), the analyzed SSA may constitute a valuable source of raw materials for the fertilizer industry.
Despite the good fertilizing properties of the SSA, in some cases the presence of heavy metals such as cadmium (0.74–1.4 mg/kg dry matter), lead (49.8–99 mg/kg dry matter), mercury (3.93 mg/kg dry matter) and arsenic (4.23–4.43 mg/kg dry matter) and poor bioavailability of P from SSA disqualifies this waste from direct use as a fertilizer. Therefore, it is necessary to look for methods that will allow the municipal SSA to be processed, for example, technologies for the extraction of phosphorus and the production of phosphate fertilizer. This way of SSA management is in the line with the CE assumptions, in which waste becomes a valuable source of secondary raw materials. Fertilizer produced from waste meeting quality, safety and labelling requirements and limits of organic, microbiological and physical contaminants will be able to be traded freely within the European Union (EU) and receive the CE marking. The idea of use of SSA for fertilizer purposes is consistent not only with the objectives of the CE but also with the Polish National Waste Management Plan 2022 and the Municipal Sewage Sludge Strategy 2019–2022, which emphasizes the necessity to maximize the use of biogenic substances contained in wastewater. Therefore, sustainable management of SSA, in particular its storage in a way enabling the recovery of phosphorus, should be promoted.
KW - Wastewater
KW - Circular economy
KW - Fertilizer
KW - Sewage sludge
KW - Phosphorus
PY - 2020
DO - https://doi.org/10.5004/dwt.2020.25113
VL - 1
SP - 1
EP - 9
PB - Desalination Publications
CY - Hopkinton, MA 01748, USA
AN - OPUS4-50646
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Hamann, Christopher
A1 - Piehl, Patrick
A1 - Weingart, Eric
A1 - Stolle, Dirk
A1 - Al-Sabbagh, Dominik
A1 - Ostermann, Markus
A1 - Auer, Gerhard
A1 - Adam, Christian
T1 - Selective removal of zinc and lead from electric arc furnace dust by chlorination–evaporation reactions
N2 - Re-melting of scrap in an electric arc furnace (EAF) results in the accumulation of filter dust from off-gas treatment that predominantly consists of iron and zinc oxides. Filter dust is classified as hazardous waste due to its high contents of potentially toxic or ecotoxic elements such as Pb, Cr, Cd, and As. A promising processing route for this waste is selective chlorination, in which the non-ferrous metal oxides are chlorinated and selectively evaporated in form of their respective chlorides from the remaining solids via the process gas flow. Here, we investigate stepwise thermochemical treatment of EAF dust with either waste iron(II) chloride solution or hydrochloric acid at 650, 800, and 1100 ◦C. The Zn and Pb contents of the thermochemically processed EAF dust could be lowered from 29.9% and 1.63% to 0.09% and 0.004%, respectively. Stepwise heating allowed high separation between zinc chloride at the 650 ◦C step and sodium-, potassium-, and lead-containing chlorides at higher temperatures. Furthermore, the lab-scale results were transferred to the use of an experimental rotary kiln highlighting the possibilities of upscaling the presented process. Selective chlorination of EAF dust with liquid chlorine donors is, therefore, suggested as a potential recycling method for Zn-enriched steelworks dusts.
KW - Electric arc furnace dust
KW - Zinc
KW - Selective Chlorination
KW - Hazardous waste
KW - Resource Recovery
PY - 2024
DO - https://doi.org/10.1016/j.jhazmat.2023.133421
SN - 0304-3894
VL - 465
SP - 1
EP - 13
PB - Elsevier
AN - OPUS4-59345
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Maresca, A.
A1 - Krüger, O.
A1 - Herzel, Hannes
A1 - Adam, Christian
A1 - Kalbe, Ute
A1 - Astrup, T. F.
T1 - Influence of wood ash pre-treatment on leaching behaviour, liming and fertilising potential
N2 - In Denmark, increasing amounts of woody biomass are being used for the production of renewable energy, resulting in more wood ashes being generated. While these materials have been mainly landfilled, wood ashes may also be utilised for fertilizing and liming purposes on top of soils. Pre-treatments involving hardening or granulation may be carried out prior to soil application. In this study, two Danish wood ash samples were hardened and/or granulated. Lab-hardening induced rapid changes in the shape of the acid neutralisation capacity curve of the ashes. Up-flow column tests, assuming local equilibrium conditions, were employed to investigate the leaching from pre-treated ashes. Granules and loose ashes demonstrated similar leaching behaviours, indicating that similar geochemical processes were governing their leaching. In comparison with untreated fresh ashes, the hardened ashes demonstrated reduced leaching of Ca, Ba, Pb and Zn with concentration levels generally below or close to the analytical limits of quantification; to the contrary, the leaching of As, P, Sb, Si, V and Mg was enhanced in the hardened ashes. The release of alkalinity was reduced by hardening. In general, all granules were barely breakable by finger-pinching and they could withstand one month of continuous leaching, preserving their overall shape. The solubility of phosphorous in neutral ammonium citrate indicated that about 30–51% of the total P content in the ash samples was released, suggesting that the ashes could be potentially valuable as P-fertiliser if applied onto soil.
KW - Wood ash
KW - Phoshpor availability
KW - Leaching
KW - Forest soils
PY - 2019
DO - https://doi.org/10.1016/j.wasman.2018.11.003
SN - 0956-053X
VL - 83
SP - 113
EP - 122
PB - Elsevier
AN - OPUS4-46583
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Smol, M.
A1 - Adam, Christian
A1 - Kugler, Stefan
T1 - Thermochemical Treatment of Sewage Sludge Ash (SSA)—Potential and Perspective in Poland
N2 - Phosphorus (P) recovery from sewage sludge ash (SSA) is one of the most promising approaches of phosphate rock substitution in mineral fertilizers and might be a sustainable way to secure supply of this raw material in the future. In the current investigation, the process of thermochemical treatment of SSA was applied to SSA coming from selected mono-incineration plants of municipal sewage sludge in Poland (Cracow, Gdansk, Gdynia, Lodz, Kielce and Szczecin).
The Polish SSA was thermochemically converted in the presence of sodium (Na) additives and a reducing agent (dried sewage sludge) to obtain secondary raw materials for the production of marketable P fertilizers. The process had a positive impact on the bioavailability of phosphorus and reduced the content of heavy metals in the obtained products. The P solubility in neutral Ammonium citrate, an indicator of its bioavailability, was significantly raised from 19.7–45.7% in the raw ashes and 76.5–100% in the thermochemically treated SSA. The content of nutrients in the recyclates was in the range of 15.7–19.2% P2O5, 10.8–14.2% CaO, 3.5–5.4% Na2O, 2.6–3.6% MgO and 0.9–1.3% K2O. The produced fertilizer raw materials meet the Polish norms for trace elements covered by the legislation: the content of lead was in the range 10.2–73.1 mg/kg, arsenic 4.8–22.7 mg/kg, Cadmium 0.9–2.8 mg/kg and mercury <0.05 mg/kg. Thus, these products could be potentially directly used for fertilizer production. This work also includes an analysis of the possibilities of using ashes for fertilizer purposes in Poland, based on the assumptions indicated in the adopted strategic and planning documents regarding waste management and fertilizer production.
KW - Sewage Sludge Ashes
KW - Critical raw materials
KW - Phosphorus
KW - Fertilizer
KW - Sewage Sludge
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514468
DO - https://doi.org/10.3390/en13205461
VL - 13
IS - 20
SP - 5461
AN - OPUS4-51446
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Herzel, Hannes
A1 - Stemann, J.
A1 - Simon, Sebastian
A1 - Adam, Christian
T1 - Comparison of thermochemical treatment of sewage sludge ash with sodium sulphate in laboratory-scale and pilot-scale experiments
N2 - There is an ongoing debate on European scale concerning the criticality of phosphorus. In Switzerland and Germany, phosphorus recovery from phosphorus-rich waste streams will become obligatory. Sewage sludge ash is rich in phosphorus and may become an important secondary feedstock. Thermochemical treatment of sewage sludge ash with sodium sulphate under reducing conditions was shown to remove heavy metals from the solid product and produce the fully plant available crystalline phase CaNaPO4. Pilot-scale experiments in a rotary kiln were carried out at temperatures between 750 and 1000 °C and were compared to laboratory-scale experiments with crucibles. Process upscaling was successfully demonstrated but a series of differences were noticed: In comparison to laboratory-scale, solubility of phosphorus in samples from pilot-scale experiments was lower at all chosen treatment temperatures because of shorter retention time and incomplete decomposition of sodium sulphate. X-ray diffraction analysis revealed remaining phase fractions of whitlockite (Ca3-x(Mg,Fe)x(PO4)2) and sodium sulphate from the starting materials in products and thus indicated incomplete reaction. In contrast to the results of laboratory-scale experiments, the crystalline phase CaNaPO4 was clearly absent in the products from the rotary kiln but instead a Mg-bearing phase (Ca,Mg)NaPO4 was formed. Laboratory-scale experiments confirmed (Ca,Mg)NaPO4 is an intermediate phase between whitlockite and CaNaPO4. However, both crystalline phases are characterized by high plant availability. It was shown that heavy metal removal increased at higher temperatures whereas solubility and thus plant availability of phosphorus already reached its maxima at temperatures of 950 °C in pilot-scale and 875 °C in laboratory-scale experiments.
KW - Crystalline phase identification
KW - Heavy metal removal
KW - Phosphorus availability
KW - Process upscaling
KW - Recovery
KW - Rhenanite
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-524084
DO - https://doi.org/10.1007/s13762-021-03252-y
VL - 19
IS - 3
SP - 1997
EP - 2006
PB - Springer
AN - OPUS4-52408
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Weimann, Karin
A1 - Adam, Christian
A1 - Buchert, M.
A1 - Sutter, J.
T1 - Environmental Evaluation of Gypsum Plasterboard Recycling
N2 - Gypsum is widely used in the construction sector and its worldwide consumption has been increasing for several decades. Depending on the life-time of the used gypsum products, an increase of gypsum in construction and demolition waste follows. Especially against the background of a circular economy, the recycling of waste gypsum is of growing importance. However, the use of recycled gypsum makes only sense if it is environmentally friendly. Therefore, an evaluation of the environmental impacts of an industrial-scale processing for the recycling of post-consumer gypsum waste was conducted. The evaluation was performed with an established life cycle assessment software. Original data provided by industry and complementary data from a database for life cycle assessments were used for the calculations. Two scenarios for recycled gypsum with different transportation distances were calculated. These results are compared with results of the environmental evaluation of gypsum derived from coal-fired power plants (FGD gypsum) and natural gypsum. The results show that utilization of recycled gypsum can be environmentally advantageous compared to the use of natural gypsum or FGD gypsum, especially in the impact categories land transformation and resource consumption (abiotic depletion potential). For most environmental impact categories the specific transportation distances have a strong influence.
KW - Gypsum plasterboards
KW - Gypsum waste
KW - Recycled gypsum
KW - Environmental evaluation
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522321
DO - https://doi.org/10.3390/min11020101
SN - 2075-163X
VL - 11
IS - 2
SP - 101
PB - MDPI
CY - Basel, Schweiz
AN - OPUS4-52232
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Herzel, Hannes
A1 - Aydin, Zeynep
A1 - Adam, Christian
T1 - Crystalline phase analysis and phosphorus availability after thermochemical treatment of sewage sludge ash with sodium and potassium sulfates for fertilizer production
N2 - Phosphorus rich sewage sludge ash is a promising source to produce phosphorus recycling fertilizer. However, the low plant availability of phosphorus in these ashes makes a treatment necessary. A thermochemical treatment (800–1000 °C) with alkali additives transforms poorly plant available phosphorus phases to highly plant available calcium alkali Phosphates (Ca,Mg)(Na,K)PO4. In this study, we investigate the use of K2SO4 as additive to produce a phosphorus potassium fertilizer in laboratory-scale experiments (crucible). Pure K2SO4 is not suitable as high reaction temperatures are required due to the high melting point of K2SO4.
To overcome this barrier, we carried out series of experiments with mixtures of K2SO4 and Na2SO4 resulting in a lower economically feasible reaction temperature (900–1000 °C). In this way, the produced phosphorus potassium fertilizers (8.4 wt.% K, 7.6 wt.% P) was highly plant available for phosphorus indicated by complete extractable phosphorus in neutral ammonium citrate solution. The added potassium is, in contrast to sodium, preferably incorporated into silicates instead of phosphorus phases. Thus, the highly extractable phase (Ca,Mg)(Na,K)PO4 in the thermochemical products contain less potassium than expected. This preferred incorporation is confirmed by a pilot-scale trial (rotary kiln) and thermodynamic calculation.
KW - Phosphorus recovery
KW - Recycling fertilizer
KW - Calcium alkali phosphate
KW - Silicate
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-536276
DO - https://doi.org/10.1007/s10163-021-01288-3
SN - 1611-8227
IS - 23
SP - 2242
EP - 2254
PB - Springer
AN - OPUS4-53627
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Raniro, H.R.
A1 - Soares, T.de M.
A1 - Adam, Christian
A1 - Pavinato, P.S.
T1 - Waste-derived fertilizers can increase phosphorus uptake by sugarcane and availability in a tropical soil
N2 - The use of highly water-soluble phosphorus (P) fertilizers can lead to P fixation in the soil, reducing fertilization efficiency. Waste-derived, low water-solubility sources can potentially increase sugarcane’s P uptake compared to triple superphosphate by reducing adsorption to the soil.
Aims:We aimed to test struvite, hazenite, and AshDec® for their agronomic potential as recycled fertilizers for sugarcane production in a typical tropical soil.We hypothesize that these sources can reduce P fixation in the soil, increasing its availability and sugarcane’s absorption.
Methods: In a greenhouse pot experiment, two consecutive sugarcane cycles, 90 days each, were conducted in a Ferralsol. The recovered sources struvite, hazenite, AshDec®, and the conventional triple superphosphate were mixed in the soil in three P doses (30, 60, and 90 mg kg–1), aside a control (nil-P). At both harvests, sugarcane number of sprouts, plant height, stem diameter, dry mass yield, shoot phosphorus, and soil P fractionation were investigated.
Results: At 90 days, struvite and hazenite performed better for dry mass yield (70.7 and 68.3 g pot–1, respectively) than AshDec® and triple superphosphate (59.8 and 57.4 g pot–1, respectively) and for shoot P, with 98.1, 91.6, 75.6, and 66.3 mg pot–1, respectively. At 180 days, struvite outperformed all treatments for dry mass yield (95.3 g pot–1) and AshDec® (75.5 mg pot–1) for shoot P. Struvite was 38% and hazenite 21% more efficient than triple superphosphate in P uptake, while AshDec® was 6% less efficient. Soil had higher labile P under struvite, hazenite, and AshDec® than triple superphosphate by the end of the first cycle, while only the later increased nonlabile P by the end of the experiment (180 days).
Conclusions:Waste-derived P sources were more efficient in supplying P for sugarcane and delivering labile P in 180 days than triple superphosphate.
KW - AshDec
KW - Hazenite
KW - P-efficiency
KW - Recycled sources
KW - Struvite
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-544216
DO - https://doi.org/10.1002/jpln.202100410
SN - 1436-8730
SP - 1
EP - 12
PB - Wiley-VCH GmbH
AN - OPUS4-54421
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schraut, Katharina
A1 - Kargl, F.
A1 - Adam, Christian
A1 - Ivashko, O.
T1 - In situ synchrotron XRD measurements during solidification of a melt in the CaO–SiO2 system using an aerodynamic levitation system
N2 - Phase formation and evolution was investigated in the CaO–SiO2 system in the range of 70–80 mol% CaO. The samples were container-less processed in an aerodynamic levitation system and crystallization was followed in situ by synchrotron x-ray diffraction at the beamline P21.1 at the German electron synchrotron (DESY). Modification changes of di- and tricalcium silicate were observed and occurred at lower temperatures than under equilibrium conditions. Despite deep sample undercooling, no metastable phase formation was observed within the measurement timescale of 1 s. For the given cooling rates ranging from 300 K s−1 to about 1 K s−1, no decomposition of tricalcium silicate was observed. No differences in phase evolution were observed between reducing and oxidizing conditions imposed by the levitation gas (Ar and Ar + O2). We demonstrate that this setup has great potential to follow crystallization in refractory oxide liquids in situ. For sub-second primary phase formation faster detection and for polymorph detection adjustments in resolution have to be implemented.
KW - Aerodynamic levitation
KW - Calcium silicate
KW - Phase formation
KW - Oxide melts
KW - In situ synchrotron x-ray diffraction
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526952
DO - https://doi.org/10.1088/1361-648X/abf7e1
VL - 33
IS - 26
SP - 264003 (12pp)
PB - IOP Publishing
AN - OPUS4-52695
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sichler, Theresa Constanze
A1 - Adam, Christian
A1 - Barjenbruch, M.
A1 - Montag, D.
A1 - Mauch, Tatjana
A1 - Sommerfeld, Thomas
A1 - Ehm, J.H.
T1 - Variation of the element composition of municipal sewage sludges in the context of new regulations on phosphorus recovery in Germany
N2 - Phosphorus (P) recovery is obligatory for all sewage sludges with more than 20 g P/kg dry matter (DM) from 2029 in Germany. Nine wastewater treatment plants (WWTPs) were chosen to investigate variations of phosphorus contents and other parameters in sewage sludge over the year. Monthly sewage sludge samples from each WWTP were analyzed for phosphorus and other matrix elements (C, N, H, Ca, Fe, Al, etc.), for several trace elements (As, Cr, Mo, Ni, Pb, Sn) and loss of ignition. Among the nine WWTPs, there are four which have phosphorus contents both above and below the recovery limit of 20 g/kg DM along the year. Considering the average phosphorus content over the year, only one of them is below the limit. Compared to other matrix elements and parameters, phosphorus fuctuations are low with an average of 7% over all nine WWTPs. In total, only hydrogen and carbon are more constant in the sludge.
In several WWTPs with chemical phosphorus elimination, phosphorus fuctuations showed similar courses like iron and/or aluminum. WWTPs with chamber flter presses rather showed dilution efects of calcium dosage. As result of this study, monthly phosphorus measurement is highly recommended to determine whether a WWTP is below the
20 g/kg DM limit.
KW - Sewage sludge
KW - Phosphorus recovery
KW - Wastewater
KW - Phosphorus elimination
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557499
DO - https://doi.org/10.1186/s12302-022-00658-4
SN - 2190-4707
VL - 34
IS - 1
SP - 1
EP - 12
PB - Springer Nature
CY - Berlin
AN - OPUS4-55749
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Sichler, Theresa Constanze
A1 - Adam, Christian
A1 - Becker, Roland
A1 - Sauer, Andreas
A1 - Ostermann, Markus
A1 - Barjenbruch, M.
T1 - Phosphorus determination in sewage sludge: comparison of different aqua regia digestion methods and ICP-OES, ICP-MS and photometric determination
N2 - Phosphorus recycling from sewage sludge will be obligatory in Germany from 2029. Phosphorus content determination in sewage sludge is crucial to assess the prescribed recycling rates. Currently, German law regards sample preparation using aqua regia digestion in a microwave or under reflux conditions as well as instrumental phosphorus determination by ICP-OES, ICP-MS, or photometric determination with ammonium molybdate as equivalent. However, it is questionable whether these methods are indeed equivalent regarding phosphorus quantification in sludges near the limit of 20 g/kg for mandatory recycling. To answer this question, 15 sewage sludges of 11 different wastewater treatment plants were investigated with all permitted method (digestion and measurement) combinations. Moreover, one sewage sludge was also examined in an interlaboratory comparison (ILC) with 28 participants. This study shows that the above-mentioned methods differ in some cases significantly but across all method combinations and sludges, phosphorus recovery was between 80 and 121% after normalization to the grand mean (average of 15 sludges between 85 and 111%). The ILC and the examination of 15 sludges produced largely similar results. There is a tendency to higher phosphorus recovery after microwave digestion compared to reflux digestion and ICP-OES measurements determine higher phosphorus contents than ICP-MS and photometric phosphorus determination. As a result, the authors recommend ICP-OES determination of phosphorus in sewage sludge after microwave digestion.
KW - Sewage sludge
KW - ICP-OES
KW - Phosphous recovery
KW - ICP-MS
KW - Photometric P determination
KW - Interlaboratory comparison
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558869
DO - https://doi.org/10.1186/s12302-022-00677-1
VL - 34
IS - 99
SP - 1
EP - 14
PB - Springer
AN - OPUS4-55886
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Dombinov, V.
A1 - Herzel, Hannes
A1 - Meiller, M.
A1 - Müller, F.
A1 - Willbold, S.
A1 - Zang, J. W.
A1 - da Fonseca-Zang, W. A.
A1 - Adam, Christian
A1 - Klose, H.
A1 - Poorter, H.
A1 - Jablonowski, N. D.
A1 - Schrey, S. D.
T1 - Sugarcane bagasse ash as fertilizer for soybeans: Effects of added residues on ash composition, mineralogy, phosphorus extractability and plant availability
N2 - Sugarcane bagasse is commonly combusted to generate energy. Unfortunately, recycling strategies rarely consider the resulting ash as a potential fertilizer. To evaluate this recycling strategy for a sustainable circular economy, we characterized bagasse ash as a fertilizer and measured the effects of co-gasification and co-combustion of bagasse with either chicken manure or sewage sludge: on the phosphorus (P) mass fraction, P-extractability, and mineral P phases. Furthermore, we investigated the ashes as fertilizer for soybeans under greenhouse conditions. All methods in combination are reliable indicators helping to assess and predict P availability from ashes to soybeans. The fertilizer efficiency of pure bagasse ash increased with the ash amount supplied to the substrate. Nevertheless, it was not as effective as fertilization with triple-superphosphate and K2SO4, which we attributed to lower P availability. Co-gasification and co-combustion increased the P mass fraction in all bagasse-based ashes, but its extractability and availability to soybeans increased only when co-processed with chicken manure, because it enabled the formation of readily available Ca-alkali phosphates. Therefore, we recommend co-combusting biomass with alkali-rich residues to increase the availability of P from the ash to plants.
KW - Combustion and gasification
KW - Phosphate extractability and availability
KW - X-ray diffraction (XRD)
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567632
DO - https://doi.org/10.3389/fpls.2022.1041924
SN - 1664-462X
VL - 13
SP - 1
EP - 13
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-56763
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Jovičević-Klug, Matic
A1 - Souza Filho, Isnaldi R.
A1 - Springer, Hauke
A1 - Adam, Christian
A1 - Raabe, Dierk
T1 - Green steel from red mud through climate-neutral hydrogen plasma reduction
N2 - AbstractRed mud is the waste of bauxite refinement into alumina, the feedstock for aluminium production1. With about 180 million tonnes produced per year1, red mud has amassed to one of the largest environmentally hazardous waste products, with the staggering amount of 4 billion tonnes accumulated on a global scale1. Here we present how this red mud can be turned into valuable and sustainable feedstock for ironmaking using fossil-free hydrogen-plasma-based reduction, thus mitigating a part of the steel-related carbon dioxide emissions by making it available for the production of several hundred million tonnes of green steel. The process proceeds through rapid liquid-state reduction, chemical partitioning, as well as density-driven and viscosity-driven separation between metal and oxides. We show the underlying chemical reactions, pH-neutralization processes and phase transformations during this surprisingly simple and fast reduction method. The approach establishes a sustainable toxic-waste treatment from aluminium production through using red mud as feedstock to mitigate greenhouse gas emissions from steelmaking.
KW - Multidisciplinary
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594424
DO - https://doi.org/10.1038/s41586-023-06901-z
SN - 0028-0836
VL - 625
IS - 7996
SP - 703
EP - 709
PB - Springer Science and Business Media LLC
AN - OPUS4-59442
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Leers, K.
A1 - Arnold, U.
A1 - Herzel, Hannes
A1 - Adam, Christian
A1 - Burkhardt, J.
T1 - Thermochemically Treated Sewage Sludge Ash From Pilot-Scale Production as P-Fertilizer for Spring Wheat and Maize in Different Soil Conditions
N2 - Background
P-fertilizers made from sewage sludge ash (SSA) may be suitable substitutes for rock phosphate (RP)-based fertilizers and contribute to sustainable use of waste. In this context, the thermochemical AshDec treatment of SSA (TC-SSA) has been continuously improved and has emerged as a possible method to produce plant-available and low-pollutant P-fertilizers. Aim Evaluation of the P-fertilizer efficacy of TC-SSA produced in pilot trials in vegetation experiments with different plants, soils, and fertilizer doses.
Methods
TC-SSA was tested in pot experiments for spring wheat and maize on different soils and at two doses (0.2 and 0.4 g fertilizer P pot−1) and is compared to untreated SSA (USSA), RP, Struvite, triple superphosphate (TSP), and a control without P-fertilization (Zero P). Pot experiments are complemented by an analysis of fertilizer P-solubility.
Results
P-solubility of SSA with different extraction methods increased due to the thermochemical treatment, whereas the water-insoluble property remained. In contrast to RP or USSA, TC-SSA enriched calcium–acetate–lactate extractable soil P to the same extent as TSP. Plant biomass and P-uptake increased with TC-SSA compared to Zero P, RP, and USSA and were in most cases equal to TSP fertilization under different soil conditions. In contrast, the effects of RP and USSA varied among soils but, mostly, did not exceed plant biomass and P-uptake of the unfertilized control.
Conclusion
TC-SSA has an increased fertilizer efficacy compared to USSA and is an effective P-fertilizer for spring wheat and maize in different soil conditions.
KW - Phosphorus
KW - Fertilizer
KW - Thermochemical
KW - Maize
PY - 2025
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-648251
DO - https://doi.org/10.1002/jpln.70035
SN - 1522-2624
VL - 189
IS - 1
SP - 81
EP - 93
PB - Wiley-VCH
AN - OPUS4-64825
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -