Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
AIT Austrian Institute of Technology GmbH, Bioresources Unit, Konrad-Lorenz-Strasse 24, 3430 Tulln, Austria.
Sci Total Environ. 2021 Feb 20;756:143726. doi: 10.1016/j.scitotenv.2020.143726. Epub 2020 Nov 24.
Production of struvite (MgNHPO·6HO) from waste streams is increasingly implemented to recover phosphorus (P), which is listed as a critical raw material in the European Union (EU). To facilitate EU-wide trade of P-containing secondary raw materials such as struvite, the EU issued a revised fertilizer regulation in 2019. A comprehensive overview of the supply of struvite and its quality is presently missing. This study aimed: i) to determine the current EU struvite production volumes, ii) to evaluate all legislated physicochemical characteristics and pathogen content of European struvite against newly set regulatory limits, and iii) to compare not-regulated struvite characteristics. It is estimated that in 2020, between 990 and 1250 ton P are recovered as struvite in the EU. Struvite from 24 European production plants, accounting for 30% of the 80 struvite installations worldwide was sampled. Three samples failed the physicochemical legal limits; one had a P content of <7% and three exceeded the organic carbon content of 3% dry weight (DW). Mineralogical analysis revealed that six samples had a struvite content of 80-90% DW, and 13 samples a content of >90% DW. All samples showed a heavy metal content below the legal limits. Microbiological analyses indicated that struvite may exceed certain legal limits. Differences in morphology and particle size distribution were observed for struvite sourced from digestate (rod shaped; transparent; 82 mass% < 1 mm), dewatering liquor (spherical; opaque; 65 mass% 1-2 mm) and effluent from upflow anaerobic sludge blanket reactor processing potato wastewater (spherical; opaque; 51 mass% < 1 mm and 34 mass% > 2 mm). A uniform soil-plant P-availability pattern of 3.5-6.5 mg P/L soil/d over a 28 days sampling period was observed. No differences for plant biomass yield were observed. In conclusion, the results highlight the suitability of most struvite to enter the EU fertilizer market.
从废物流中生产鸟粪石（MgNHPO·6HO），以回收磷（P），磷被欧盟列为关键原材料。为了促进欧盟范围内的磷含量二次原材料（如鸟粪石）贸易，欧盟在 2019 年修订了肥料法规。目前，还缺乏对鸟粪石供应及其质量的全面概述。本研究旨在：i）确定欧盟目前的鸟粪石生产规模，ii）评估所有法定的理化特性和病原体含量是否符合新设定的监管限值，并 iii）比较不受监管的鸟粪石特性。据估计，2020 年欧盟回收的鸟粪石中磷含量在 990-1250 吨之间。从 24 个欧洲生产厂的鸟粪石中取样，占全球 80 个鸟粪石装置的 30%。有三个样品未能通过理化法定限值；一个样品的磷含量<7%，三个样品的有机碳含量超过干重的 3%（DW）。矿物学分析表明，六个样品的鸟粪石含量为 80-90% DW，13 个样品的鸟粪石含量>90% DW。所有样品的重金属含量均低于法定限值。微生物分析表明，鸟粪石可能超过某些法定限值。从消化液（棒状；透明；82 质量%<1mm）、脱水液（球形；不透明；65 质量%1-2mm）和上流式厌氧污泥床反应器处理马铃薯废水（球形；不透明；51 质量%<1mm 和 34 质量%>2mm）中得到的鸟粪石的形态和粒径分布存在差异。在 28 天的采样期内，观察到土壤-植物磷利用率为 3.5-6.5mg P/L 土壤/d 的统一模式。未观察到对植物生物量产量的差异。总之，结果表明，大多数鸟粪石适合进入欧盟肥料市场。
