Lime stabilization

Lime stabilization originated in Texas after World War II, and now it is used throughout the world. Lime is most commonly applied at a 4 wt % application or ca 11 kg/m (20 Ib/yd ) for 15 cm of compacted depth. It can be applied dry as hydrated time or granular quicklime or as a wet slurry. Distribution of the latter form is dusfless. Copious amounts (as much as 5—10%) of water are always needed in excess of the optimum moisture content of the soil. Then, a requisite for success is intimate mixing with a rotary mixer, followed by compaction to a minimum of 95% Proctor density. 

Spent pickle liquor is considered a hazardous waste (K062) because it contains considerable residual acidity and high concentrations of dissolved iron salts. For example, spent pickle liquor and waste acid from the production of stainless steel is considered hazardous. The hazardous constituents in K062 are lead, nickel, and hexavalent chromium. Waste pickle liquor sludge generated by lime stabilization of spent pickle liquor is not considered hazardous unless it exhibits one or more of the characteristics of hazardous waste. An estimated 6 million tons of spent pickle liquor are generated annually in the U.S.1... 

Fig. 12.17 Breakthrough curves for a conservative tracer (Ck) and lime-stabilized biosolid (LSB), aerobically digested biosolid (ADB), and poultry-manure biosolid (PMB) colloids eluted from intact (a) Maurry, (b) Woolper, and (c) Bruno soil monoliths (C, effluent concentration, C, influent concentration, (after Karathanasis et al. 2005)...

Note CEC = cation exchange capacity HISM = hydroxyinterlayered smectite HIV = hydroxyinterlayered vermiculite Kf = Freundlich metal distribution coefficients LSB = lime stabilized biosolids = total aluminosilicates. 

This study investigated the role of colloid particles with or without carbonates dispersed from lime-stabilized biosolids to mediate the transport of associated metals through intact soil monoliths in laboratory leaching experiments. The biosolid colloids were applied to undisturbed soil monoliths of a Maury soil under steady rate (2.2 cm/lr1) gravity flow conditions. Deionized water spiked with metals at levels similar to the total load (soluble plus sorbed) carried by the colloids was used as a control leaching treatment. The eluents were monitored for colloid, Cu, Zn, and Pb breakthrough concentrations. 

These findings indicate that even though the lime stabilization process of the biosolid waste may contribute to increased immobilization of soluble metals by sorption or precipitation onto the solid phase, in retrospect, it could create conditions favorable for increased dispersion and mobility of colloid particles and their metal load. 

The aim of this work is to study the effect of polyamide strips on engineering properties of lime stabilized clayey sands. 

Two important parameters can be considered and discussed, when polyamide 66 as reinforcing fibers is used in lime stabilized clayey sand samples namely compressive and tensile strength. In essence, in soil stabilization one of the most important factors that should be considered is the modification of tensile strength. Because, as a general rule, soils like other construction materials such as concrete and asphalt mixtures has low tensile strength. 

In our previous studies [2,3], we have shown that for lime-stabilized clayey sand, a parabolic behavior for the stress- strain curve is expeeted. Hence, for our polyamide reinforced materials, a similar behavior can be observed. This is presented in equation 2 for stabilized speeimens containing 15% lime ... 

Tabtabaei, A., 1982, Application of Lime Stabilized Geomaterials in Road Construction, TechnicalJournal of Tehran University, No. 44, pp. 47-58. 

Chlorine stahilization is one of a number of chemical stabilization processes, involving the use of chlorine. For instance, if lime is used in a chemical stabilization process for sludge treatment, it is a lime stabilization process. 

S. Dou, C.R. Masson and P.D. Pacey, Mechanism of oxygen permeaHon through lime-stabilized zirconia. /. Electrochem. Soc., 132 (1985) 1843-1849. 

Arabi M, Wild S, Rowlands GO (1989) Frost resistance of lime-stabilized clay soil. Transp Res Rec 1219 93... 

Lime stabilization for an access road at Heathrow airport, London, England. 

The properties developed by compacted cement or lime-stabilized soils are governed by the amount of cement or lime added on the one hand and compaction on the other. With increasing cement or lime content, the strength and bearing capacity increase, as does the durability to wet-dry cycles. The permeability generally decreases but tends to increase in clayey soils. 

Bell, F.G. 1996a. Lime stabilization of clay minerals and soils. Engineering Geology, 42, 223-237. 

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