Characterization of organic particulates present in milk factory process waters used for reuse along with aerobically digested effluent wastewater
- Authors: Verheyen, Vincent , Cruickshank, Alicia , Wild, Karl , Heaven, M. , McGee, R. , Watkins, Mark , Nash, David
- Date: 2010
- Type: Text , Journal article
- Relation: Bioresource Technology Vol. 102, no. 2 (2010), p. 2118-2125
- Full Text: false
- Reviewed:
- Description: Wastewater from a dairy processor is being reused and recycled both within the plant and for irrigation. Flash pyrolysis GC–MS was used to examine nitrogen and phenol containing compounds (M.W. = 35 to 450 g/mol) in the particulate fraction of the milk condensate, combined clean wastewater and aerobic bioreactor effluent. For comparison, the particulates were also prepared for standard GC–MS analyses using conventional solvent extraction methods. Compounds detected by pyrolysis GC–MS were found mostly in the bioreactor with the amino acid arginine (220 mg/kg) and the amino acid derivative 1-methyl-5-oxo-L-proline methyl ester (130 mg/kg) found at the highest concentrations. In comparison, sterols detected in the effluent were found at higher concentrations when using solvent extraction indicating some degradation with pyrolysis GC–MS. However, with few exceptions, particulates were generally found not to act as passive collectors capable of concentrating less water soluble chemicals.
Structural elucidation of humic acids extracted from Pakistani lignite using spectroscopic and thermal degradative techniques
- Authors: Nasir, Saqib , Sarfaraz, Tahira , Verheyen, Vincent , Chaffee, Alan
- Date: 2011
- Type: Text , Journal article
- Relation: Fuel Processing Technology Vol. 92, no. 5 (2011/05/01/ 2011), p. 983-991
- Full Text: false
- Reviewed:
- Description: The present paper describes the characterization of Pakistan lignite coal, derived humic acids (HAL) and nitrohumic acids (NHA) along with the standard leonardite humic acids (LHA). The study utilized chromatographic and spectroscopic techniques to characterize the structure of coal and derived materials. Pyrolysis coupled to gc/ms was conducted with and without methylating agent (tetramethyl ammonium hydroxide). The pyrolysis study resulted in releasing mainly fatty acid methyl esters, different series of hydrocarbons and α, ω-dicarboxylic acid methyl esters. Triterpenoids, syringic and ρ-coumaric compounds and aromatic compounds derived from lignin moieties were also detected. Fourier transform infrared (FT-IR) and NMR data helped to evaluate the influence of coal rank on regeneration and nitration processes with respect to chemical structural composition of coal and derived materials. FT-IR spectra of four materials were similar except that NHA showed an absorption band at 1532cm−1, thus confirming the presence of -NO2 groups. 13C NMR indicated higher aromaticity and less hydroxylalkyl material in HAL than NHA. The elemental composition and acid functional group content of four materials were also reported. The combination of results from different analytical techniques gives an improved understanding of the Pakistan coal nature and helpful for its future utilization.
Characterization of organic compounds in biochars derived from municipal solid waste
- Authors: Taherymoosavi, Sarasadat , Verheyen, Vincent , Munroe, Paul , Joseph, Stephen , Reynolds, Alicia
- Date: 2017
- Type: Text , Journal article
- Relation: Waste Management Vol. 67, no. (2017), p. 131-142
- Full Text: false
- Reviewed:
- Description: Municipal solid waste (MSW) generation has been growing in many countries, which has led to numerous environmental problems. Converting MSW into a valuable biochar-based by-product can manage waste and, possibly, improve soil fertility, depending on the soil properties. In this study, MSW-based biochars, collected from domestic waste materials and kerbsides in two Sydney's regions, were composted and pyrolysed at 450 °C, 550 °C and 650 °C. The characteristics of the organic components and their interactions with mineral phases were investigated using a range of analytical techniques, with special attention given to polycyclic aromatic hydrocarbons and heavy metal concentrations. The MSW biochar prepared at 450 °C contained the most complex organic compounds. The highest concentration of fixed C, indicating the stability of biochar, was detected in the high-temperature-biochar. Microscopic analysis showed development of pores and migration of mineral phases, mainly Ca/P/O-rich phases, into the micro-pores and Si/Al/O-rich phases on the surface of the biochar in the MSW biochar produced at 550 °C. Amalgamation of organic phases with mineral compounds was observed, at higher pyrolysis temperatures, indicating chemical reactions between these two phases at 650 °C. XPS analysis showed the main changes occurred in C and N bonds. During heat treatment, N-C/C=N functionalities decomposed and oxidized N configurations, mainly pyridine-N-oxide groups, were formed. The majority of the dissolved organic carbon fraction in both MSW biochar produced at 450 °C and 550 °C was in the form of building blocks, whereas LMW acids was the main fraction in high-temperature-biochar (59.9%). © 2017 Elsevier Ltd
Advances in the thermo-chemical production of hydrogen from biomass and residual wastes : summary of recent techno-economic analyses
- Authors: Shahabuddin, M. , Krishna, Bhuvya , Bhaskar, Thallada , Perkins, Greg
- Date: 2020
- Type: Text , Journal article , Review
- Relation: Bioresource Technology Vol. 299, no. (2020), p.
- Full Text: false
- Reviewed:
- Description: This article outlines the prospects and challenges of hydrogen production from biomass and residual wastes, such as municipal solid waste. Recent advances in gasification and pyrolysis followed by reforming are discussed. The review finds that the thermal efficiency of hydrogen from gasification is ~50%. The levelized cost of hydrogen (LCOH) from biomass varies from ~2.3–5.2 USD/kg at feedstock processing scales of 10 MWth to ~2.8–3.4 USD/kg at scales above 250 MWth. Preliminary estimates are that the LCOH from residual wastes could be in the range of ~1.4–4.8 USD/kg, depending upon the waste gate fee and project scale. The main barriers to development of waste to hydrogen projects include: waste pre-treatment, technology maturity, syngas conditioning, the market for clean hydrogen, policies to incentivize pioneer projects and technology competitiveness. The main opportunity is to produce low cost clean hydrogen, which is competitive with alternative production routes. © 2019 Elsevier Ltd
Effect of sewage sludge derived compost or biochar amendment on the phytoaccumulation of potentially toxic elements and radionuclides by Chinese cabbage
- Authors: Černe, Marko , Palčić, Igor , Major, Nikola , Pasković, Igor , Perković, Josipa , Užila, Zoran , Filipović, Vilim , Romić, Marija , Goreta Ban, Smiljana , Jaćimović, Radojko , Benedik, Ljudmila , Heath, David John , Ban, Dean
- Date: 2021
- Type: Text , Journal article
- Relation: Journal of environmental management Vol. 293, no. (2021), p. 112955-112955
- Full Text: false
- Reviewed:
- Description: This study set out to evaluate the effect of using sewage sludge-derived compost (SSC) or biochar (SSB) as a soil amendment on the phytoaccumulation of potentially toxic elements, PTE (Cd, Cr, Cu, Ni, Pb, Zn) and natural radionuclides (238U and 232Th) by Chinese cabbage (Brassica rapa L. subsp. pekinensis (Lour.) Hanelt) in terra rossa and rendzina soils, which are the two common soil types in Croatia. The experiment consisted of a greenhouse pot trial using a three-factor design where soil type, sludge post-stabilisation procedure and amendment rate (12 and 120 mgP/L) were the main factors. At harvest, the concentrations of analytes in the substrate, leaves and roots were measured, from which the edible tissue uptake (ETU) and concentration ratios (CR) were determined. Also, the average daily dose (ADD) and hazard quotient (HQ) were determined to assess the health risk, as well as soil contamination factor (CF). The results showed that neither adding SSC nor SSB affected the soil loading at the rates applied, suggesting a low risk of soil contamination (CF ≤ 1). The ETU of Cd, Cu, and Zn were 0.0061, 1.23, and 0.91 mg/plant from compost-amended soil and 0.0046, 0.78 and 0.65 mg/plant for biochar-amended soil, respectively. This difference suggests that their ETU was higher in compost-amended soils than in soils treated with biochar. The CR data indicate that the bioavailability of Cu (CR of 5.30) is highest at an amendment rate of 12 mgP/L, while for Zn (CR of 0.69), the highest bioaccumulation was observed with an amendment rate of 120 mgP/L. Translocation of Cr, Ni, Pb and 238U to the leaves was limited. Overall, the HQ (<1) for Cd, Cu and Zn in the edible parts confirmed that consuming Chinese cabbage does not threaten human health. Similarly, the daily intake of 232Th remained below the limit (3 μg) set by ICRP, suggesting no radiological risk. Finally, although the amendment rate, which was 10-times the amount stipulated in Croatian regulation and the CR ranged from 0.007 to 5.30, the precautionary principle is advised, and the long-term impact of sewage sludge derived compost or biochar on different plant groups (incl. root vegetables) at the field-scale is recommended. [Display omitted] •Sewage sludge compost or biochar amendment did not result in soil contamination.•Biochar amendment reduced Cd, Cu and Zn edible tissue uptake relative to compost use.•No evidence of phytoaccumulation of Cr, Ni, Pb and 238U in Chinese cabbage leaves.•Levels of Cd, Cu, Zn and 232Th in the edible tissues does not pose a health risk.