reduction of heavy metals in sewage sludge during composting

... with Ministry of Science, Technology and Environment, Ministry of Planning and Investment, have invested the matter in various hospitals and submitted the project of constructing “the centre of ... more easily by using one of the latest technologies – Biofast – a kind of machine for filtering liquid wastes Biofast are outstanding because of its effectiveness and efficiency Biofast operates ... Vietnamese factories tried manufacturing incinerators but either they could not apply in reality or incinerators were inefficient The abatement cost of treating one kilogram of solid medical waste is 8,000vnd...

Ngày tải lên: 23/09/2012, 15:38

... Settling rate experiments (Figure 2.2) indicated a decline in the concentration of kaolinitic colloids remaining in suspension at pH

Ngày tải lên: 11/08/2014, 10:22

... unraveling the affinity of mineral surfaces for both inorganic and organic species The main effects of proton adsorption-desorption on the adsorption of metals in general and heavy metals in particular ... structure of phyllosilicate clays plays a key role in determining the final state of clay particles in aqueous media The presence of structural charges, neutralizing cations, and the capacity of forming ... reactivity of surface groups The charge of ions in ionic crystals is neutralized by the surrounding ions of opposite charge According to Pauling’s principle of electroneutrality,3 the charge of a cation...

Ngày tải lên: 11/08/2014, 10:22

... main thrust of our research will be trying to incorporate mineral surfaces into the aqueous-phase models we have presented here Generating accurate models of systems containing water, NOM, metals, ... environmental interest that may interact with NOM, the matrix of possible models is enormous A primary assumption in tackling this daunting problem is that a number of controlling parameters and guiding ... of silica complexation.85 Another area of great interest is the complexation of amino acids with metals such as Cu2+ because these complexes may play a role in the bioavailability of copper in...

Ngày tải lên: 11/08/2014, 10:22

... rates of catalysis of Mn oxidation For example, recent investigations in a wetland in New York State found many different genetic strains of Leptothrix, each exhibiting different rates of catalysis ... OXIDES IN CONTROLLING TRACE METAL ADSORPTION TO NATURAL BIOFILMS Given the high adsorption capacity of biogenic Mn oxide, we conducted investigations to estimate the magnitude of the in uence of ... present in many natural aquatic systems This indicates a significant role for biogenic Mn oxides in the scavenging of toxic transition metals in aquatic environments Additional experiments in natural...

Ngày tải lên: 11/08/2014, 10:22

... successful in identifying Zn-bearing phases in the subsoil, indicating that Zn was not found in abundant portions in any one phase Aluminum, Si, and Fe in the maps in the subsurface soil indicated ... minerals in the matrix which may cause fluorescence, resulting in an interference with the spectrum of the central element of interest (e.g., for Co and Ni in samples containing Fe oxides in a significant ... missing secondshell backscattering in the presence of minerals with strong second-shell backscattering.31 This latter point often leads to an inability to successfully detect minor metal-bearing...

Ngày tải lên: 11/08/2014, 10:22

... dissolved by increasing concentrations of a reducing agent The destabilization of Fe and Mn oxides following the addition of a reducing agent to a contaminated soil caused an increase in the soluble ... importance of cation exchange versus specific adsorption of metals is increased at lower pH The apparent greater specific adsorption of Ni by the Mogote soil cannot be explained in terms of differences in ... important in uence on the changes in the solubility of Mn and other trace metals under reducing conditions for these soils In certain situations, it will be necessary to include specific adsorption in...

Ngày tải lên: 11/08/2014, 10:22

... explained by the degradation of compounds of low molecular weight during the formation of peat and the anaerobic digestion of sewage sludge Liang et al (1996) reported that following composting ... to the mineral surfaces Therefore, composting organic wastes would increase the adsorption of DOM on soils because of the increase in aromatic carbon-containing compounds after composting (Liang ... pointed out that the HiB fraction mainly consisted of the N-containing group, including most amino acids, amino sugar, low-molecular-weight amines, and pyridine, while the HiA fraction contained...

Ngày tải lên: 11/08/2014, 10:22

... high-resolution imaging, but may interfere with performing microanalysis by increasing electron backscattering at the expense of specimen x-rays while producing x-rays characteristic of the metal coating Therefore, ... techniques, including some of those discussed in this chapter, are inherently biased in favor of the larger materials that represent less of the reactive surface area for contaminant sorption, and in ... and LaB6 instruments, respectively, with image signals originating from surficial regions of the sample closer to the initial probe location The in uence of sample coating on SEM imaging and EDS...

Ngày tải lên: 11/08/2014, 10:22

... by mining and smelting, production and use of materials containing the heavy metals, burning of fossil fuels, leaching of waste dumps, urban run-off, sewage effluent, shipping, waste dumping ... Together with increasing use of heavy metals, the level of heavy metal pollution has increased dramatically over the years Anthropogenic sources of heavy metals in coastal environments include industrial ... speciation of heavy metals in local marine sediments, levels of heavy metals in coastal mangrove habitats The main objectives of this research were (i) to evaluate the prevailing heavy metal levels in...

Ngày tải lên: 10/11/2015, 12:34

... Contents of metal in soft tissue of Laternula anatine 130 Figure 4.28 Contents of metal in soft tissue of Geloina coaxans 131 Figure 4.29 Contents of metal in soft tissue of Lingula unguis ... Contents of metal in soft tissue of Crassostrea rivularis 132 Figure 4.31 Contents of metal in soft tissue of Anatina antiquate 133 Figure 4.32 Contents of metal in soft tissue of Solens ... Contents of metal in soft tissue of Tapes literatus 135 Figure 4.34 Contents of metal in soft tissue of B.rana 135 Figure 4.35 Contents of metal in soft tissue of K hiantina ...

Ngày tải lên: 22/05/2016, 11:02

... form of heavy metals in sewage sludge as well as its transportation during treatment process [l] Efficiency of removing heavy metals from sewage sludge depends on compound form of heavy metals ... in sewage sludge which are effect on transporting and bleaching of heavy metal from sewage sludge In which, it is necessary to pay more attention to heavy metal mobilization mechanisms in sewage ... animal origin and 70o/o vegetable origin grinding machine and mixed with municipal sewage sludge follow ratio three part of organic waste by volume and one part of municipal sewage sludge by volume...

Ngày tải lên: 24/06/2015, 08:16

... activated sludge reactors were treating the sewages discharged in the campus of Beijing University of Technology In addition to the sewages, acetate was also fed to MO and A2N Table - The summary of ... A2N Sewage Sewage, acetate 17 14 15 0.04 0.04 Continuous Carrousel Ditch Continuous University of Cape Town CD MUCT Sewage Sewage 20 28 15 18 0.02 0.04a) Sequencing Anaerobic-oxic SBR-1 Sewage ... activated sludge reactors were operated at Beijing University of Technology, Beijing, China Five reactors were continuous type and other two reactors were sequencing batch ones These activated sludge...

Ngày tải lên: 05/09/2013, 09:38

... Content of lead (median) (mg/kg) in soil profiles of spruce (left) and beech (right) stands Zinc The contents of zinc are higher in the area of Jablunkov Pass than in the remaining area of NFR ... determination of pH using a glass electrode in a 1:5 suspension of soil in water (pH in H2O) or in 0.01 mol/L calcium chloride solution (pH in CaCl2) Parameters Ntot and Ctot were determined using near infrared ... Horizon upper-most mineral mineral mineral forest floor Horizon forest floor in comparison with the remaining area of NFR The spatial distinctness of distribution of this element in the Jablunkov...

Ngày tải lên: 07/08/2014, 10:21

... Distribution of heavy metal concentration of sewage sludge in China 2012 International Conference on Biomedical Engineering and Biotechnology, 1354– 1356 Zinck J (2005) Review of disposal, reprocessing ... distribution of heavy metals including rare Earth elements, thorium, and uranium in sludge from industry water treatment plant and recovery method of metals by biosurfactants application Bioinorg Chem ... FEG-EPMA) to investigate the release behavior of HMs and As from industrial sludges of southern Vietnam The sludges are chemically distinct, making it possible to distinguish groups of elements...

Ngày tải lên: 18/08/2016, 15:47

... bacteria in these conditions The time courses of NH4+-N and NO2+3 N in batch experiment are shown in Fig Gradual decrease in NH4+-N and increase in NO2+3 N were observed just after the beginning of ... gene of AOB belonging to the ß subclass of Proteobacteria The thermal profiles included an initial denaturing step at 95°C for 10 followed by 45 cycles of denaturation at 95°C for 20 s, annealing ... courses of the copy number of amoA mRNA and the number of ammonia oxidizer are shown in Fig No significant change and difference in the number of ammonia oxidizer was observed in each run During...

Ngày tải lên: 05/09/2013, 10:15

... expensive – dioxins are a good example – which is an additional factor to be kept in mind when discussing monitoring of organics in sludges Monitoring must also pay attention to the origin of sludge because ... Finland and United Kingdom reusing the highest percentage of their sludges in agriculture (> 70%) 1.1 Definitions The terminology used in this review follows the definitions given in the Working ... compounds in sludge of rd different countries and as suggested in the draft of the “Working paper on sludge 12 Tabel 3.1-1: Standards for concentrations of organic contaminants in sewage sludge in different...

Ngày tải lên: 14/02/2014, 03:20

... coefficient indicates the increasing trend (positive) or decreasing trend (negative) of the precipitation anomaly index It is seen that drought conditions increase during the three first sub-periods in ... is calculated in the range [3]: In this paper the frequency and intensity of the drought periods in Central Vietnam is investigated during the period 1961-2007 2.1 Data Monthly rainfall data gathered ... Central Vietnam in which the first period 1961-1970 has the largest rate of change The increasing trends of dry conditions also happen in 1961-1970 and 19811990 in South Central and during the first...

Ngày tải lên: 14/03/2014, 15:20

... flow in rainy periods The stream collected wastewaters of local industries, some of which operating in the electroplating field, and its floods caused an accumulation of contaminants, mainly of inorganic ... defined, since the phenomena of redistribution and adsorption usually take place during extractions: in any case the partitioning of the metals into five fractions gives an indication of their ... of metals in the five fractions are reported in Table Of course, when considering these data, the extent of metal recovery (see Section 2.3.6) must be taken into account It must be borne in mind...

Ngày tải lên: 15/03/2014, 23:56