This paper presents results that illustrate the recycling of a bamboo derived sorbent used for the capture of elemental mercury (Hg0). The bamboo derived sorbent used is essentially a HCl functionalized activated carb...This paper presents results that illustrate the recycling of a bamboo derived sorbent used for the capture of elemental mercury (Hg0). The bamboo derived sorbent used is essentially a HCl functionalized activated carbon prepared from carbonization and CO2 activation of raw bamboo, that could potentially provide an alternative way to existing methods in removing mercury from flue gases from coal-fired plants. In this study, the bamboo derived sorbents were tested in a batch test using a mercury permeation tube as the source and nitrogen as a carrier gas. The recycling or regeneration of an activated carbon is an important issue to address from a coal-fired power plant point of view, and an attempt has been made to test the behavior of bamboo derived sorbents with various treatments including carbonized, carbonized-activated, carbonized-activated-acidulated, and then a follow-up recycled run after sample treatments in gas phase. From the study, it was found that bamboo derived activated carbon can be successfully acidulated using various normalities of HCl where weak solutions can be very effective in functionalizing the surface of the sorbent and capturing mercury. In order to recycle and reuse bamboo derived sorbents, stronger normalities of HCl would be desired.展开更多
Phosphorus (P) and Nitrogen (N) deficiencies are recognized as the major constraint of agricultural productivity in developing countries including Zambia. While N deficits can be restored at least in part through the ...Phosphorus (P) and Nitrogen (N) deficiencies are recognized as the major constraint of agricultural productivity in developing countries including Zambia. While N deficits can be restored at least in part through the application of crop residues and manure, the restoration of soil P can only be achieved by use of phosphate fertilizers which are unaffordable by the small scale farmers. The aim of the study was to assess the availability of P for crop use from rock phosphate (RP), partially acidulated by acid produced by sulfur oxidizing bacteria. The RP was obtained from Keren Mining Limited at Sinda district, Zambia;the Pyrite rock (iron sulfur) and bacteria culture were obtained Nampundwe mine dump. The pyrite and PR were ground and mixed with the bacterial culture to produce the Partially Acidulated Rock Phosphate (PARP). A pot experiment was set up in a CRB design in a greenhouse on four soil types with four treatments of: soil alone (control), soil with GRP, soil with PARP and soil with super single phosphate (SSP) replicated four times. The results showed that the plant height, biomass yield and P uptake across the different P sources showed significant differences (p < 0.01);particularly, the PARP and SSP were significantly higher than the both control and the GRP. A comparison of PARP and SSP within each soil based on both biomass yield and P uptake showed no significant difference between them. Despite the fact that the RAE values based on biomass yield were in most cases higher than those base on the P uptake, the trend was the same. On average the PARP was >90% effective within and across the four soils indicating that the PARP is reactive and suitable for direct application for crop production.展开更多
文摘This paper presents results that illustrate the recycling of a bamboo derived sorbent used for the capture of elemental mercury (Hg0). The bamboo derived sorbent used is essentially a HCl functionalized activated carbon prepared from carbonization and CO2 activation of raw bamboo, that could potentially provide an alternative way to existing methods in removing mercury from flue gases from coal-fired plants. In this study, the bamboo derived sorbents were tested in a batch test using a mercury permeation tube as the source and nitrogen as a carrier gas. The recycling or regeneration of an activated carbon is an important issue to address from a coal-fired power plant point of view, and an attempt has been made to test the behavior of bamboo derived sorbents with various treatments including carbonized, carbonized-activated, carbonized-activated-acidulated, and then a follow-up recycled run after sample treatments in gas phase. From the study, it was found that bamboo derived activated carbon can be successfully acidulated using various normalities of HCl where weak solutions can be very effective in functionalizing the surface of the sorbent and capturing mercury. In order to recycle and reuse bamboo derived sorbents, stronger normalities of HCl would be desired.
文摘Phosphorus (P) and Nitrogen (N) deficiencies are recognized as the major constraint of agricultural productivity in developing countries including Zambia. While N deficits can be restored at least in part through the application of crop residues and manure, the restoration of soil P can only be achieved by use of phosphate fertilizers which are unaffordable by the small scale farmers. The aim of the study was to assess the availability of P for crop use from rock phosphate (RP), partially acidulated by acid produced by sulfur oxidizing bacteria. The RP was obtained from Keren Mining Limited at Sinda district, Zambia;the Pyrite rock (iron sulfur) and bacteria culture were obtained Nampundwe mine dump. The pyrite and PR were ground and mixed with the bacterial culture to produce the Partially Acidulated Rock Phosphate (PARP). A pot experiment was set up in a CRB design in a greenhouse on four soil types with four treatments of: soil alone (control), soil with GRP, soil with PARP and soil with super single phosphate (SSP) replicated four times. The results showed that the plant height, biomass yield and P uptake across the different P sources showed significant differences (p < 0.01);particularly, the PARP and SSP were significantly higher than the both control and the GRP. A comparison of PARP and SSP within each soil based on both biomass yield and P uptake showed no significant difference between them. Despite the fact that the RAE values based on biomass yield were in most cases higher than those base on the P uptake, the trend was the same. On average the PARP was >90% effective within and across the four soils indicating that the PARP is reactive and suitable for direct application for crop production.
