Browsing by Author "Frederickson, Jim"

Now showing 1 - 4 of 4
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    Application of DR4 and BM100 Biodegradability tests to treated and untreated organic wastes
    (2007-10) Godley, Andrew R.; Lewin, Kathy; Frederickson, Jim; Smith, Richard; Blakey, N.
    The aerobic DR4 and anaerobic BM100 biodegradability tests are currently applied in England and Wales for monitoring the reduction in biological municipal waste (BMW) achieved by mechanical biological treatment (MBT) plants (Environment Agency 2005). The protocol is applied only when outputs are landfilled and is based on estimating the reduction in potential biogas production between the MBT input, municipal solid waste (MSW), and all of the landfilled outputs, using the BM100 test. As this is a long term 100 day test the more rapid 4 day DR4 test may also be applied as this has been shown to correlate with the BM100 test. We have now applied the DR4 and BM100 tests to 132 organic waste samples including untreated and treated BMW and specific organic wastes. The results indicate that the correlation between the DR4 and BM100 tests has proved valid for mixed MSW derived BMW wastes. However when both tests are applied to specific organic wastes such as turkey feathers, cardboard packaging waste and pizza food wastes the correlation between the tests is less strong. It is concluded that the use of the DR4 and BM100 test correlation is valid for its designed application (monitoring MBT processes treating MSW derived mixed BMW), but that caution should be exercised when applying both tests to specific single component organic wastes.
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    Characterisation of untreated and treated biodegradable wastes
    (2007-10) Godley, Andrew R.; Frederickson, Jim; Lewin, Kathy; Smith, Richard; Blakey, N.
    As part of a Defra sponsored project (WRT220), approximately 40 biodegradable wastes were characterised according to biodegradability (DR4 and BM100), total PTE content, C:N ratio and biochemical composition. Two leaching tests were employed; upflow percolation test and a one step LS10 test; eluates were analysed for TOC, pH, electrical conductivity, PTEs and a range of cations and anions. This paper contains a limited set of data for a selection of untreated and treated waste types representing four waste treatment processes (composting, MBT, MHT, anaerobic digestion). The DR4 and BM100 tests were found to be appropriate for a wide range of waste types but where possible they should be used in conjunction with other related tests. Longer-term MBT composting processes appeared to produce compost material with reduced ammonium concentrations and extractability of some PTEs. Carbon content (carbon analyzer - LECO) could be estimated as C = LOI/1.9 which is a routine operation. N LECO values were approximately 12% greater than the equivalent N Kjeldahl values.
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    Charaterisation of treated wastes to support an evidence base for sustainable waste management.
    (The Waste Conference Limited, 2006-09) Lewin, Kathy; Godley, Andrew R.; Turrell, J.; Smith, Richard; Frederickson, Jim; Graham, Adele; Gronow, Jan R.; Blakey, N.
    Defra must consider policies and strategies to manage environmental challenges such as climate change and sustainability. At a basic level the strategies need good quality data on waste characteristics. The dataset for UK wastes, in particular the new generation of treated wastes, is not fit for this purpose. This paper outlines the gaps in knowledge needed to underpin policy development and initial findings from a new project funded under Defra’s Waste and Resource Management Research Programme. The project team from WRc, Open University and Cranfield University aims to improve understanding of the characteristics of treated organic and inorganic wastes, methods of testing and knowledge of treatment process performance. Potential opportunities from the research are also described. New data will be collated into the presentation.
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    Comparison of a novel enzymatic biodegradability test method with microbial degradation methods
    (2008-01-01T00:00:00Z) Wagland, Stuart Thomas; Godley, Andrew R.; Frederickson, Jim; Tyrrel, Sean F.; Smith, Richard
    A novel enzymatic hydrolysis test (EHT) has been evaluated as a surrogate for conventional microbial biodegradability methods, using 37 assorted organic waste samples collected from diverse sources. The results of the EHT method are compared with those obtained from two conventional tests; the 4 day aerobic DR4 and 100 day anaerobic BM100 test methods currently applied in England and Wales. The EHT is based on the enzymatic hydrolysis of cellulosic materials and can be completed in less than 24 hours. Linear regression for 37 samples against the BM100 data showed the DR4 provided a correlation coefficient of r = 0.58; the EHT method gave a correlation of r = 0.62 for the total DOC release; and r = 0.77 for the DOC released from enzymatic hydrolysis. The correlations suggest that the EHT method may be better suited to a wider range of waste types when correlating with anaerobic BM100 test results since it more closely mimics the full extent of decomposition rather than that from the readily biodegradable fraction.