Solid-to-Liquid Ratio

Hamel S.C., Buckley B., Lioy P.J. Bioaccessibility of metals in soils for different liquid to solid ratios in synthetic gastric fluid. Environ Sci Technol 1998 32 358-362. 

Adaptability to extremely low flowing liquid-to-solid ratios, so that it is possible to obtain a relatively concentrated solution from a relatively lean solid parent material... 

Leaching of chemicals from complex materials or matrices is a complicated phenomenon in which many factors may influence the release of the specific organic compounds and inorganic ions. Important factors include major element chemistry, pH, redox, complexation, liquid to solid ratio, contact time, and biological activity. To describe fully the leaching of SWMs/COMs under field conditions, a battery of leaching tests was specifically designed to simulate various physical and chemical release mechanisms. 

LDH LEU LIBD LAW LET LILW LIP LLNL LLW LMA LMFBR LOI LREE L/S LTA LWR Layered double hydroxide Low enriched uranium Laser-induced breakdown detection Low-activity waste Linear energy transfer Low- and intermediate-level nuclear waste Lead-iron phosphate Lawrence Livermore National Laboratory Low-level nuclear waste Law of mass action Liquid-metal-cooled fast-breeder reactor Loss on ignition Light rare earth elements (La-Sm) Liquid-to-solid ratio (leachates) Low-temperature ashing Light water reactor... 

Formation of free milk fat in DWM powder particles as a result of atomization and drying may also contribute significantly to poor solubility and dispersibility. Free milk fat, which is extractable from the powder by a 50 50 mixture (v/v) of ethyl and petroleum ether (Brunner, 1974), probably coats the powder particles and prevents their rehydration. The physical state of the milk fat, as controlled by the liquid-to-solid ratio and the presence of free milk fat on the particle surface, strongly influences DWM particle dispersibility. Spray coating of DWM particles with lecithin or other surfactants and dispersion in warm water improve their dispersibility. 

NaX and NaY zeolites (Union Carbide) were exchanged by lithium, potassium, and caesium in a 1 M solution of the corresponding metal chloride at 80°C for 60 min, using a liquid to solid ratio of 10. The samples were then filtered and washed free of chlorides. After drying, the zeolite was pelletized, crushed, and sieved to different particle sizes. 

Assessment of the ecotoxicological potential hazard of leachate fluxes (Liquid-to-Solid ratio and time-dependent release)... 

Chemical and ecotoxicological characterization of leachates i function of liquid-to-solid ratio and time ... 

In the WASTOXHAS procedure, ecotoxicity testing of leachate samples obtained at different liquid-to-solid ratios (or at different times of release) aims at measuring effects on species representing various levels of biological organization (see Section 5.4) as a function of dilution rate while controls without leachate are used as reference. In order to express results in a synthetic form, raw data obtained from concentration-response curves are transformed into a summary criterion corresponding to a specific measurement endpoint (e.g., EC5o, ECX, NOEC, LOEC, etc.) for each test (Fig. 3). 

As stated by Van der Sloot (1998), several factors can influence the release of contaminants from both granular and monolithic materials. These include major element chemistry, pH, redox status of the system, presence of complexants, humic substances or other dissolved organic compounds, liquid to solid ratio, and biological activity. 

Table 5. Prerequisite study - Ecotoxicity data of leachates of a municipal solid waste incinerator bottom ash (BA) and a slag from a second smelting of lead (2SL) obtained after following the draft standardEN12457 (2002) using liquid-to-solid ratios (L/S) of 2 and 10.

Figure 7. Downward-flow column study - Toxicity responses of the Microtox test and the algal test on BA leachates in relation to the liquid-to-solid ratio (L/S).

EN 12457-1 (2003) Characterization of waste - Leaching - Compliance test for leaching of granular waste materials and sludges - Part 1 One-stage batch test at a liquid to solids ratio of 2 L/kg for materials with high solids content and with a particle size below 4 mm (with or without size reduction), CEN/TC292/WG2, European Committee for Standardization, Brussels. 

ISWMP Integrated Solid Waste Management Plans LOEC Lowest observed effect concentration L/S liquid to solid ratio... 

BSG was obtained from Sociedade Central de Cervejas (Vialonga, Portugal). The raw material was mixed with water at an 8 1 (w/w) liquid-to-solid ratio and pretreated in an autoclave (Uniclave 88, AJC, Lisbon, Portugal) for 1 h at 100°C for residual starch removal. The solid was separated by filtration, washed and dried at 50°C to reach a moisture below 10% (w/w) (2), homogenized to obtain a uniform lot, and stored in PA/PE vacuum-sealed bags. 

Starch-free BSG was subjected to reaction with water (autohydrolysis) in a 2-L stainless steel Parr reactor model 4532 (Moline, IL), to cause the hydrolytic degradation of hemicelluloses, operating under optimized conditions (liquid-to-solid ratio of 8 1 [w/w], standard heating temperature profile up to 190°C, isothermal reaction at 190°C for 2.5 min) (2). After the reactor was cooled down, the oligosaccharide-containing liquor (OCL) was separated from the residual solid by filtration (Whatman no. 1 filter paper). 

The feedstock was mixed with 3% (w/w) sulfuric acid solution in 500-mL closed universal flasks with a liquid-to-solid ratio of 8 (w/w). The moisture content of the samples was included as water in the material balances. The mixtures were allowed to stand for 10 min at room temperature in order to equilibrate the acid concentrations between the bulk phase and biomass. Hydrolysis was performed in an autoclave at 130°C for pre-established isothermal periods ranging from 2 to 240 min. The flasks were placed inside the autoclave at 100°C, and the heating time to reach 130°C was recorded. After the reaction time had elapsed, the autoclave was rapidly cooled down and the hydrolysate and solid phase were recovered by filtration (Whatman no. 1 filter paper). All experiments were done at least in duplicate. 

The hydrothermal transformation process, described with the crystallization curves shown in Figure 3.10, was carried out using zeolite Na-HC (the chemical and phase composition of this sample was given in Tables 4.1 and 4.2 besides, in Figure 3.11, the SEM micrograph corresponding to sample HC [119] is shown) with the following procedure the Na-HC was hydrothermally treated with a 7.5M NaOH and 0.6M NaCl (liquid to solid ratio = 1) solution and statically heated at 373 K in methyl polypropylene bottles [119]. 

Application context of the tests (verification tests, compliance tests, and characterization tests). Most of the compliance tests applied to solidification/ stabilization waste are short term tests involving high liquid to solid ratios and which sometimes include crushing of the materials. Such tests are not appropriate to understanding leaching behavior or for the prediction of release from solidification/stabilization wastes. 

Several advantages and disadvantages of a trickle-bed reactor are listed in Table 1-5. The commercial trickle-bed reactors are operated under plug-flow conditions. The catalysts are effectively wetted. These factors allow high conversion to be achieved in a single reactor. The liquid-to-solid ratio (or liquid holdup) in a trickle-bed reactor is small, thus minimizing the importance of homogeneous... 

Liquid-to-solid ratio is small, minimizing the homogeneous side reactions if possible. 

High liquid holdup and liquid-to-solid ratio in an upflow reactor. High liquid holdup will offer more liquid-phase resistance to the mass transfer of the gaseous reactant to the catalyst surface. High liquid-to-solid ratio will give more importance to the role of possible homogeneous reactions. 

High liquid-to-solid ratio, thus allowing more homogeneous reactions. This may not be desirable. High liquid holdup will also offer more resistance to the transfer of gas to the catalyst surface. 

Using these equations, it is possible to use the simple beaker test data to calculate expected phytochemical extract concentrations and recoveries at the temperature and particle size of the beaker test for various liquid-to-solids ratios for each successive extraction with fresh solvent. 

Conversely, the liquid-to-solids ratio can be determined by defining the inlet and outlet concentrations for stages 2 through n and determining the operating line between these two points. 

The liquid-to-solids ratio cannot be less than the weight fraction of liquid retained in the marc, or... 

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