Using sufficient amount of lime (to provide enough alkalinity), compaction of the soil to high density and prompt placement after mixing lime with soil (to minimize carbon dioxide penetration) can minimize potential carbonation problems. In a lime treated soil, if sulfates are present in the soil or water, then these sulfates may react with alumina released from clay and calcium from lime to form ettringite (Ca6[Al(OH)6]2. (SO4)3.26H2O) (Mohamed, 2000). Ettringite has the capability of imbibing large volumes of water and dramatically increases the swelling potential of the lime-stabilized soil. It would be prudent to test and understand whether lime, soil, and sulfate swell or not when mixed and exposed to moisture, if sulfates are present where lime stabilization is
STABILIZATION OF CLAYEY SOIL USING CHEMICALS Bhawna Sahay1, Prof. V.K.Arora2 ABSTRACT: Soil stabilization is a technique of enhancing the geotechnical properties and strength of soil to modify the bearing capacity and durability of weak soil. There are numerous methods of stabilising the soil such as soil replacement , grouting ,reinforcing ,chemical, mechanical, electrical method, using additives such as fly ash, rice husk, gypsum and cement. Chemical stabilization with lime and sodium hydroxide is time saving method. All these chemicals are highly reactive in nature and react with clay particles during stabilization process which leads to improve the geotechnical properties of soil. KEY WORDS: stabilization; optimum
These results showed that the preparation layer is a mixture of lime (CaO) and sand (SiO2). The presences of S essentially owed to the pollution of sulphure dioxide. The occurrence of Na and Cl are indicative of the existence of halite (NaCl), whose presence is due to materials used in the ground layer or moisture. The presence of aluminum oxide and potassium oxide are from dust. The presence of MgO owed to limestone which had been used in makes lime.
However, the silver particles formed may exhibit broad size distributions or form several different particle geometries simultaneously. 3) Reduction via sodium borohydride A similar method is the reduction of silver nitrate using sodium borohydride, NaBH4.Sodium borohydride is a stronger reducing agent than citrate, but it does not participate in surface stabilization. Thus, a separate capping molecule must be used in addition to the sodium borohydride. Examples of stabilizers or capping molecules used include citrate, poly(vinyl pyrrolidone) (PVP),bovine serum
The chemical oxide composition of OPC clinker and lime stone theoretical phase ratios calculated by Bogue formulae are presented in Table 1. Propylene glycol provided from Aldrich-sigma was used as grinding aids. Commercial grinding aids (CG) was used as reference grinding aids used in market. 2.2.preparation of dry mixes During the grinding of OPC clinker, the grinding aids are added with the ratios 0, 0.03, 0.04 and 0.05 wt.% of the clinker. OPC-limestone blended cement (PLC) are prepared by replacement 5 and 10 wt.% of OPC by limestone.
Some of these materials are called pozzolans, which by themselves do not have any cementitious properties, but when used with Portland cement, react to form cementitious compounds. SCM are primarily used for improved workability, durability and strength. They modify the microstructure of concrete and reduce its permeability thereby reducing the penetration of water and waterborne salts into concrete
In all such instances, chemical sludges are formed. A normal use in removing a substance from wastewater is the chemical rain of phosphorus. The chemicals utilized for phosphorus removal contain lime, alum, and “pickle liquors” such as ferrous chloride, ferric chloride, ferrous sulfate, and ferric sulfate. A little treatment plants add the chemicals to the biological process; therefore, chemical precipitates are varied alongside the biological sludge. Most plants apply chemicals to secondary effluent and use tertiary clarifiers or tertiary filters to remove the chemical precipitates.
EXPERIMENTAL Mass transfer tests The mass transfer tests in the test reactor (2 L Büchi autoclave) where conducted using an indirect (chemical) method. The experimental procedure (detailed in Section 6.1.3) consisted of filling the reactor with approximately 1.2 mol/L sodium sulfite solution containing 1-5 mg/L cobalt(II) ion, turning on the oxygen supply and starting the time. The oxidation reaction was allowed to continue for a predetermined time agitation was started and samples taken at regular time intervals. Each sample was mixed with excess standard iodine solution and titrated with standard sodium thiosulfate solution (Na2S2O3) using a starch indicator. The reactions are (Jeffrey et al., 1989): 〖"SO" 〗_"3" ^"2-" "+ " "I" _"2" "+ " "H" _"2" "O → " 〖"SO" 〗_"4" ^"2-" "+ " 〖"2H" 〗^"+" "+ " 〖"2I" 〗^"-" 6.1 〖"2S" 〗_"2" "O" _"3" ^"2-" "+ " "I" _"2" "→ " "S" _"4" "O" _"6" ^"2-" "+ " 〖"2I" 〗^"-" 6.2 The residual amount of sulphate was determined by the stoichiometry of the reaction 6.2.
Stabilizers are used in ice cream mix to increase its viscosity (Marshal et. al, 2003). Other more terms for stabilizers are colloids, hydrocolloids, and gums which designate they are polysaccharide and capable of interacting with water. The interaction with water allows some of these compounds to interact with some proteins and lipids in the mix (Kilara et al,
Soda ash is added to facilitate easy melting, limestone increases the durability of the product and dolomite is added to improve the working and weathering properties. Other materials may be used as colorants or refining agents. The percentage composition of the raw materials has been shown in the table below. Material Percentage Composition Sand 72.6 Soda ash 13.0 Limestone