Batch leaching tests

Batch tests (i. e., tests on individual waste materials) are conducted with the provided solid suspensions (e.g., soils such as Woodburn, Sagehill, and Olyic, as well as two bottom sediment samples) prepared with previously air-dried solids (i. e., soils and bottom sediments), ground to a uniform powdery texture for mixing with the eluates from the 24-h batch leaching test of the different SWMs/COMs. The concentrations of eluates in solution were designed to evaluate the capability of different environmental solids to adsorb available contaminants. The solid particles were fully dispersed with the aqueous phase to achieve complete adsorption. Common practice is to use a solid solution ratio of 1 g 4 ml [ 1 ], together with proper tumbling of the samples at a constant temperature (e.g., at least 24 h in a constant temperature environment of 20°C). 

Batch leaching tests, conducted for different types of waste materials, resulted in data that were modeled as shown in Eq. (94) ... 

Batch leaching tests. The results of batch leaching with deionized water using the UK fly ashes from Drax and Meaford power stations are shown in Table 3. Three different fly ash samples were used in the study Drax fresh,... 

Batch leaching tests are generally taken as an initial step to evaluate toxicity of the ashes because the batch tests represent the best leaching conditions and generate the highest quantity of leachates (Benito et al. 2001). Serial batch leaching tests also often successfully simulate ash pond conditions (Praharaj et al. 2002), whereas the column leaching tests simulate dry ash disposal (Benito et al. 2001). 

Stook, K., Tolaymat, T., Ward, M. et al. (2005) Relative leaching and aquatic toxicity of pressure-treated wood products using batch leaching tests. Environmental Science and Technology, 39(1), 155-63. 

Sequential batch leaching A batch leaching test where a solid sample is leached in successive volumes of different types of leaching solutions (compare with serial batch leaching, leaching test, column leaching, and batch leaching). 

WASTOXHAS was developed for assessing leaching hazardous impact of wastes in laboratory and field situations. It is a part of a tiered approach (Fig. 1). It assumes that classical batch leaching tests (see for example Sahuquillo et al., 2003), followed by application of relevant bioassays, have been initially undertaken for i) deciding to continue ecotoxic hazard assessment and ii) selecting adequate and sensitive bioassays. It can be eventually followed by a more complex and elaborate hazard assessment scheme based on microcosms or mesocosms. ... 

Three bioassays a) 48h acute rotifer test (Brachionus plicatilis) b) 120d chronic sea anemone test (Aiptasia pallida) c) Acute (48h) and chronic (19d) marine copepod test (Acartia tonsa) MSWI bottom and fly ash leachates Column and batch leaching tests with ocean water and acidic artificial rain... 

Four bioassays a) 30 min acute bacterial test (Vibrio fischeri) b) 72h algal test (Pseudokirchneriella subcapitata) c) Acute (24h) and chronic (28d) crustacean test (Daphnia magna) d) 48h plate incorporation AMES test (Salmonella typhimurium his-with TA 97a, 98, 100, 102) Industrial solid waste leachates Batch leaching test with demineralized water followed by paper filtration (crude leachate), Liquid/liquid extraction (organic extract), lyophilization (lyophilized extract. pH adjusted according to tolerance of organisms and 0.22 pm filtration for AMES test... 

Single batch leaching tests (equilibrium based) Multiple batch and percolation/column testst ... 

Results of batch leach tests performed on tailings from the Grants Mineral Belt, New Mexico are summarized in Tables IV and V. These results represent the average of two analyses on the acid leach tailings samples. Table IV contains the elemental concentrations of the sand and silt and clay-sized fractions, as well as the soluble concentration of each element found when 100 g of material is leached with 250 mL of sodium hexametaphosphate solution. The right-most column presents the ratio of the elemental concentration associated with the silt and clay-sized fraction to that of the sand-sized fraction, and it is presented as an enrichment factor. The high enrichment factors for As, Mo, Cr, Se, and V may be due to the fact that these elements are adsorbed onto jarosite, montmorillonite, and ferric oxyhydroxides (9-141. Speciation... 

Batch leaching tests are designed to determine rates of desorption and equilibrium sorption relationships imder conditions of high mixing, high surface areas of the construction material, and continuous surface renewal [1-4,240-... 

Caldwell RJ,Stegmann JA,Chao CC (1994) Ultrasonic agitation method for accelerated batch leaching tests. In Proc 3rd Int Symp on Stabilization/Solidification of Hazardous, Radioactive and Mixed Wastes, Williamsburg, VA,ASTM, Philadelphia, PA, p 423... 

Batch The short-term (24-h) batch leaching test is conducted to provide... 

Several kinds of leaching test methods are provided in the Netherlands from the viewpoint that the single batch leaching test shows one side of the elution behavior of the waste. Because the behavior of elution for powdery samples is different from those for a molded body, the leaching tests are different depending on the form of each sample. In addition, three kinds of test methods for the powdery waste are prepared to investigate the time dependency of dissolution behavior, as listed in Table 4. 

In solids that ctmtain vascular sterns, D, parallel to the vascular bundle mqr be twice as large as it is at right angles to the bundle. Furthermore, in sudi solids, D, as determined from batch leaching tests increases as the particle size irrcreases (below a threshold size of 3-5 rttm). hr dense cdlular materials, on the other hand, roptured surfirce cells make up a progressively smaller fraction of the particle volunre as size increases D, consequendy decreases slightly as particle size increases. 

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