Browsing by Author "Bolan, Nanthi"

Now showing 1 - 3 of 3
  • Thumbnail Image
    ItemOpen Access
    A critical review on risk evaluation and hazardous management in carcass burial
    (Elsevier, 2019-01-23) Chowdhury, Saikat; Kim, Geon-Ha; Bolan, Nanthi; Longhurst, Philip
    Carcass disposal from livestock disease outbreaks or on-farm, routine mortalities present a number of challenges. Proper management of carcasses can no longer be addressed as an incidental occurrence, as they represent a persistent pathway of infectious agricultural wastes with potential to harm the environment. The long-term management of carcass disposal sites is essential irrespective of the cause of mortality. Critically this ensures eradication of disease and environmental protection from a range of biological and chemical hazards. Strategies for large-scale carcass disposal require preparation and coordinated, proactive planning in advance of emergencies to meet environmental protection guidelines and maximize the efficiency of response. Carcass disposal methods include burial, incineration, composting, alkaline hydrolysis, lactic acid fermentation and anaerobic digestion. Burial techniques include trench burial, landfill, and notably mass burial as one of the most common methods of disposal. However, there are concerns about possible impacts to the environment and subsequent risk to human health regardless of the initial logistical and economic advantages. This review provides an overview of our current understanding of the potential threats of carcass burial and possible management options. The environmental implications of terminating burials is discussed as is the role of biochar and phytoremediation which can contribute to the management of burials. These examples are considered in the case study context of Korea where long-term considerations remain a priority. The outcome of the review is structured to provide information to decision-makers that is of value when equipping themselves with comprehensive guidelines for the sustained management of carcass burials. Finally, recommendations that address future research needs are outlined.
  • Thumbnail Image
    ItemOpen Access
    The effects of light regime on carbon cycling, nutrient removal, biomass yield, and polyhydroxybutyrate (PHB) production by a constructed photosynthetic consortium
    (Elsevier, 2022-09-12) Wicker, Rebecca J.; Autio, Heidi; Daneshvar, Ehsan; Sarkar, Binoy; Bolan, Nanthi; Kumar, Vinod; Bhatnagar, Amit
    Microalgae can add value to biological wastewater treatment processes by capturing carbon and nutrients and producing valuable biomass. Harvesting small cells from liquid media is a challenge easily addressed with biofilm cultivation. Three experimental photobioreactors were constructed from inexpensive materials (e.g. plexiglass, silicone) for hybrid liquid/biofilm cultivation of a microalgal-bacterial consortia in aquaculture effluent. Three light regimes (full-spectrum, blue-white, and red) were implemented to test light spectra as a process control. High-intensity full-spectrum light caused photoinhibition and low biomass yield, but produced the most polyhydroxybutyrate (PHB) (0.14 mg g−1); a renewable bioplastic polymer. Medium-intensity blue-white light was less effective for carbon capture, but removed up to 82 % of phosphorus. Low-intensity red light was the only net carbon-negative regime, but increased phosphorus (+4.98 mg/L) in the culture medium. Light spectra and intensity have potential as easily-implemented process controls for targeted wastewater treatment, biomass production, and PHB synthesis using photosynthetic consortia.
  • Thumbnail Image
    ItemOpen Access
    Retrieving back plastic wastes for conversion to value added petrochemicals: opportunities, challenges and outlooks
    (Elsevier, 2023-06-01) Kumar, Manish; Bolan, Shiv; Padhye, Lokesh P.; Konarova, Muxina; Foong, Shin Ying; Lam, Su Shiung; Wagland, Stuart T.; Cao, Runzi; Li, Yang; Batalha, Nuno; Ahmed, Mohamed; Pandey, Ashok; Siddique, Kadambot H.M.; Wang, Hailong; Rinklebe, Jörg; Bolan, Nanthi
    Plastic production and its unplanned management and disposal, has been shown to pollute terrestrial, aquatic, and atmospheric environments. Petroleum-derived plastics do not decompose and tend to persist in the surrounding environment for longer time. Plastics can be ingested and accumulate into the tissues of both terrestrial and aquatic animals, which can impede their growth and development. Petrochemicals are the primary feedstocks for the manufacture of plastics. The plastic wastes can be retrieved back for conversion to value added petrochemicals including aromatic char, hydrogen, synthesis gas, and bio-crude oil using various technologies including thermochemical, catalytic conversion and chemolysis. This review focusses on technologies, opportunities, challenges and outlooks of retrieving back plastic wastes for conversion to value added petrochemicals. The review also explores both the technical and management approaches for conversion of plastic wastes to petrochemicals in regard to commercial feasibility, and economic and environmental sustainability. Further, this review work provides a detailed discussion on opportunities and challenges associated with recent thermochemical and catalytic conversion technologies adopted for retrieving plastic waste to fuels and chemicals. The review also recommends prospects for future research to improve the processes and cost-efficiency of promising technologies for conversion of plastic wastes to petrochemicals. It is envisioned that this review would overcomes the knowledge gaps on conversion technologies and further contribute in emerging sustainable approaches for exploiting plastic wastes for value-added products.