Zhang Z.,University of Canterbury |
Pang S.,University of Canterbury |
Levi T.,CRL Energy Ltd.
Renewable Energy | Year: 2017
This study investigated effects of blending ratio and alkali and alkaline earth metallic (AAEM) species in the feedstock on char reactivity and producer gas composition in steam co-gasification of chars of blended coal and biomass. Experiments were conducted on a bench-scale fixed bed gasifier in which lignite was used as coal and radiata pine was used as biomass. The blending ratios of lignite to pine (L/P) were, respectively, 0:100 (pure pine), 20:80, 50:50, 80:20 and 100:0 (pure lignite). Lignite and radiata pine were first separately ground to fine particles which were then blended based on pre-set ratios. After this, the blends were pelletized and charred at 900 °C. In order to investigate the effect of AAEM in the coal, experiments were also performed using blended pine and acid-washed lignite from which most of AAEM species were effectively removed. The co-gasification operation temperature was 950 °C. From the experimental results, it was found that the ratios of H2/CO, H2/CO2 and CO/CO2 in the producer gas were nonlinearly related to L/P ratio in the lignite blended chars; however, these gaseous ratios were linearly correlated to the L/P ratio in co-gasification of acid-washed lignite blended chars. In addition, by removing the AAEM species in lignite, yields of H2 and CO2 were reduced while CO yield was increased. The char reactivity of acid-washed lignite and pine blends was decreased and this decrease became more significant with increase in coal to biomass blending ratio. © 2016
Korolevych V.Y.,CRL Energy Ltd. |
Kim S.B.,CRL Energy Ltd.
Journal of Environmental Radioactivity | Year: 2013
Concentrations of organically bound tritium (OBT) and tissue-free water tritium (TFWT, also referred to as HTO) in fruits and tubers were measured at a garden plot in the vicinity of the source of chronic airborne tritium emissions during the 2008, 2010, and 2011 growing seasons. A continuous record of HTO concentration in the air moisture was reconstructed from the continuous record of Ar-41 ambient gamma radiation, as well as from frequent measurements of air HTO by active samplers at the garden plot and Ar-41 and air HTO monitoring data from the same sector. Performed measurements were used for testing the modified Specific Activity (SA) model based on the assumption that the average air HTO during the pod-filling period provides an appropriate basis for estimating the levels of OBT present in pods, fruits and tubers. It is established that the relationship between the OBT of fruits and tubers and the average air HTO from a 15-20 day wide window centred at the peak of the pod-filling period is consistent throughout the three analysed years, and could be expressed by the fruit or tuber's OBT to air-HTO ratio of 0.93 ± 0.21. For all three years, the concentration of HTO in fruits and tubers was found to be related to levels of HTO in the air, as averaged within a 3-day pre-harvest window. The variability in the ratio of plant HTO to air HTO appears to be three times greater than that for the OBT of the fruits and tubers. It is concluded that the OBT of fruits and tubers adequately follows an empirical relationship based on the average level of air HTO from the pod-filling window, and therefore is clearly in line with the modified SA approach. © 2012.
Trumm D.,CRL Energy Ltd.
New Zealand Journal of Geology and Geophysics | Year: 2010
Treatment of acid mine drainage can be accomplished by either active or passive treatment systems. Choice between active and passive treatment and appropriate selection of systems within each category is critical for treatment success. In general, active treatment is more commonly used at operational mines whereas passive treatment is typically considered for closed and abandoned mines. Operational mines often have limited space for remediation systems and have large and fluctuating flow rates with changing drainage chemistry as mining proceeds, factors that are addressed more easily with active than passive treatment. In the long term, passive treatment could offer more economic options than active treatment. Various flow charts have been prepared by previous researchers to help select among the passive systems but little work has been done to help select between active and passive treatment or to select appropriate active treatment systems. Furthermore, the passive treatment flow charts have often not included variables important for application to New Zealand sites: topography, climate and available land area. Very steep topography, dense and often protected vegetation, and a high-rainfall climate may result in acid mine drainage with high flow rates in locations with limited space for remediation. This paper presents flow charts specific to New Zealand which have been prepared to accommodate topography and available land area. © 2010 The Royal Society of New Zealand.
CRL Energy Ltd. | Date: 2014-08-21
CRL Energy Ltd. | Date: 2016-03-22
CRL Energy Ltd. | Date: 2014-09-22
CRL Energy Ltd. | Date: 2011-08-02
Systems, methods and compositions for the production of silicon nitride nanostructures are herein disclosed. In at least one embodiment, a carbon feedstock is preprocessed, combined with a silicon feedstock and annealed in the presence of a nitrogen containing compound to produce a silicon nitride nanostructure.
CRL Energy Ltd. | Date: 2015-10-06
CRL Energy Ltd. | Date: 2015-10-06
CRL Energy Ltd. | Date: 2014-06-16