Systematic Evaluation of the Fate of Phosphorus in Fluidized Bed Combustion of Biomass and Sewage Sludge

Falk, Joel; Skoglund, Nils; Grimm, Alejandro; Öhman, Marcus

doi:10.1021/acs.energyfuels.9b03975

Cited by 18 publications

(4 citation statements)

References 48 publications

(119 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous studies have further shown that by adding K to the SS fuel mixture, plant-available phosphates in the form of K-whitlockites can be formed . Recently published research about co-combustion of SS with K-rich fuels suggests that K-phosphates are formed to a larger extent at higher temperatures of 1100–1200 °C compared to 800 °C. , However, thermodynamic equilibrium calculations (TECs) for the co-combustion of SS and K-rich agricultural fuels indicate that the formation of K-bearing phosphates is thermodynamically favored at lower temperatures relevant for fluidized bed combustion . There are also new TEC databases with enhanced applicability in P-rich systems that need to be assessed and compared to experimental results.…”

Section: Introductionmentioning

confidence: 99%

Single Pellet Combustion of Sewage Sludge and Agricultural Residues with a Focus on Phosphorus

et al. 2021

Self Cite

View full text Add to dashboard Cite

Recycling of phosphorus in combination with increased utilization of bioenergy can mitigate material and global warming challenges. In addition, co-combustion of different fuels can alleviate ash-related problems in thermal conversion of biomass. The aim of this study is to investigate the ash transformation reactions of mainly P in co-combustion of P-rich sewage sludge (SS) with K-rich sunflower husks (SH) and K-and Si-rich wheat straw (WS). Single pellets of 4 mixtures (10 and 30 wt % SS in WS and 15 and 40 wt % SS in SH) and pure SS were combusted in an electrically heated furnace at process temperatures relevant for fluidized bed combustion (800 and 950 °C). Collected ash fractions were analyzed by inductively coupled plasma techniques, ion chromatography, scanning electron microscopy− energy-dispersive X-ray spectroscopy, and X-ray diffraction. Thermodynamic equilibrium calculations were performed to interpret the results. Over 90% of K and P was found to be captured within the residual ash with 30−70% P in crystalline K-bearing phosphates for mixtures with low amounts of SS (WSS10 and SHS15). The significant share of K and P in the amorphous material could be important for P recovery. For the lower percentage mixtures of SS (WSS10 and SHS15), P in crystalline phases was mainly found in K-whitlockite and CaKPO 4 . For the higher percentage SS mixtures, most of P was found in whitlockites associated with Fe and Mg, and no crystalline phosphates containing K were detected. For P recovery, co-combustion of the lower SS mixtures is favorable, and they are suggested to be further studied concerning the suitability for plant growth.

show abstract

Section: Introductionmentioning

confidence: 99%

Single Pellet Combustion of Sewage Sludge and Agricultural Residues with a Focus on Phosphorus

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…The association of phosphorus in biomass ash and char has been studied by numerous researchers. However, Öhman (refs , , , , , , , , , , , , , , , – ), Boström (refs , , , , , , , , , , , , – , – ), Skoglund (refs , , , , , , , , , , , , – , – , ), and their co-workers have performed considerable work within the field and should be acknowledged for investigating the fate of phosphorus in various types of biomass, and the combustion characteristics of several phosphorus-rich biomass types. In this section, a conceptual model developed by them, to aid the understanding of phosphorus transformation(s) in biomass ash, will first be presented.…”

Section: Transformation Of Phosphorus In Biomass Conversionmentioning

confidence: 99%

Review of Phosphorus Chemistry in the Thermal Conversion of Biomass: Progress and Perspectives

et al. 2023

View full text Add to dashboard Cite

Phosphorus is vital for all life, which means that phosphorus is present in all biomass to some extent. Some types of biomass, such as certain agricultural residues, animal biomass, and sewage sludge, contain high levels of phosphorus. In thermal conversion of biomass, high levels of phosphorus can cause various operational problems. Extensive work has been carried out to understand the phosphorus chemistry taking place at higher temperatures. However, until now, knowledge about transformation chemistry and fate of phosphorus during thermal conversion of biomass was not easily accessible in one place. In this work, the outcome of an extensive literature review has been summarized. First, an introduction to the role of phosphorus in biomass, and in what forms it may be present, is given. Different analytical techniques relevant for characterization of phosphorus in biomass, biomass char, and biomass ash are described. A classification of phosphorus-rich biomass is proposed, and the potential of different phosphorus-rich biomass types is presented. To provide a common basis for the field of high-temperature phosphorus chemistry, fundamental chemistry relevant for thermal conversion of biomass is first discussed. This includes the gas phase chemistry and reaction pathways of light phosphorus species, pyrolysis, and combustion of organophosphorus compounds, and solid, liquid, and gaseous interactions with other ash-forming elements. Thereafter, an in-depth review of phosphorus transformations in biomass, including decomposition of organic phosphorus, ash transformations in the condensed phase, release to the gas phase, and formation of particulate matter in the flue gas follows. Finally, the review covers research focusing on phosphorus in different application aspects, such as the use of phosphorus as an additive to mitigate operational problems related to slag and deposit formation, the behavior of phosphorus in fluidized bed technologies, corrosion, and the deactivation of SCR catalysts.

show abstract

“…It is stated that volatile K can be captured by aluminum silicates. Furthermore, crystalline phases containing potassium and phosphorus have been identified in ash from phosphorous-rich DSS such as sewage sludge, which are mainly in the form of CaK 2 P 2 O 7 , MgKPO 4 , and CaKPO 4 [20,25,26].…”

Section: Chemical Fractionationmentioning

confidence: 99%

Pyrolysis of Municipal Sewage Sludge to Investigate Char and Phosphorous Yield together with Heavy-Metal Removal—Experimental and by Thermodynamic Calculations

et al. 2021

View full text Add to dashboard Cite

Sewage sludge is regarded as a potential source for soil fertilizer However, the direct utilization of sewage sludge in agricultural land is restricted since it also contains heavy metals, pathogens, and toxic compounds. Pyrolysis of the sewage sludge destroys the organic pollutants and partly volatilizes the heavy metals. In this study, pyrolysis of sewage sludge was carried out in order to determine the optimum residence time and temperature to recover the phosphorous and remove heavy metals from the resultant sewage sludge char (SSC). Pyrolysis was conducted on dried sewage sludge (DSS) by means of thermogravimetric analysis (TGA) and high-temperature oven with an N2-atmosphere. Microwave Plasma-Atomic Emission Spectroscopy (MP-AES) was used to determine the concentration of P and trace elements in the resulting solid char fraction. A combination of chemical fractionation (step-by-step leaching) of the DSS and thermodynamic equilibrium calculations were utilized to estimate the availability of phosphorous and removal of heavy metals in the SSC fraction at different temperatures. The results from the thermodynamics calculation were in line with the measured chemical composition of the SSC. Furthermore, the energy contents of the SSC obtained at different temperatures were measured. The pyrolysis evaluation results indicate that phosphorous was enriched in the char, while lead, zinc, and cadmium were significantly removed.

show abstract

Systematic Evaluation of the Fate of Phosphorus in Fluidized Bed Combustion of Biomass and Sewage Sludge

Cited by 18 publications

References 48 publications

Single Pellet Combustion of Sewage Sludge and Agricultural Residues with a Focus on Phosphorus

Single Pellet Combustion of Sewage Sludge and Agricultural Residues with a Focus on Phosphorus

Review of Phosphorus Chemistry in the Thermal Conversion of Biomass: Progress and Perspectives

Pyrolysis of Municipal Sewage Sludge to Investigate Char and Phosphorous Yield together with Heavy-Metal Removal—Experimental and by Thermodynamic Calculations

Contact Info

Product

Resources

About