Lime hydrate

Most carbide acetylene processes are wet processes from which hydrated lime, Ca(OH)2, is a by-product. The hydrated lime slurry is allowed to settle in a pond or tank after which the supernatant lime-water can be decanted and reused in the generator. Federal, state, and local legislation restrict the methods of storage and disposal of carbide lime hydrate and it has become increasingly important to find consumers for the by-product. The thickened hydrated lime is marketed for industrial wastewater treatment, neutrali2ation of spent pickling acids, as a soil conditioner in road constmction, and in the production of sand-lime bricks. 

Carbide lime is a waste lime hydrate by-product from the generation of acetylene from calcium carbide and may occur as a wet sludge or dry powder of widely varying purity and particle size. It is gray and has the pungent odor associated with acetylene (see Hydrocarbons, acetylene). 

Pat lime is a pure lime (quick or hydrated), as distinct from an impure or hydraiflic lime it is also used to denote a lime hydrate that yields a plastic putty for stmctural purposes. 

Dime putty is a form of lime hydrate in a wet, plastic paste form, containing free water. 

Milk-of-lime is a dilute lime hydrate in aqueous suspension which has the consistency of milk. 

Hydrated lime is also used to stabilize the calcium sulfite—sulfate sludge derived from thickeners at SO2 scmbbing plants that use limestone—lime. Hydrated lime (2—3%) is added to react with the gypsum sludge and flyash or other added siHceous material. Under ambient conditions the lime and siHca serve as a binder by reacting as calcium siHcates so that the material hardens into a safe, nonleaching, stable, sanitary landfill or embankment fill. 

Alum, fine 45-50 B265 Lime, hydrated, Vh in and under 40 B26YZ... 

Lime is among a family of chemicals which are alkaline in nature and contain principally calcium, oxygen and, in some cases, magnesium. In this grouping are included quicklime, dolomitic lime, hydrated lime, dolomitic hydrated lime, limestone, and dolomite. The most commonly used additives are quicklime and hydrated lime, but the dolomitic counterparts of these chemicals (i.e., the high-magnesium forms) are also widely used in wastewater treatment and are generally similar in physical requirements. 

Synonyms Slaked lime hydrated lime calcium hydrate... 

Ca(0H)2 Slaked lime, hydrated lime, calcium hydroxide. A saturated... 

Calcium oxide (CaO, lime, quicklime, unslaked lime) is differentiated from calcium hydroxide [Ca(OH)2, slaked lime, hydrated lime] and limestone (CaC03, calcite, calcium carbonate, marble chips, chalk) by formula and by behavior. A saturated solution of calcium oxide in water is called limewater and a suspension in water is called milk of lime. 

The aim of the experiments was to obtain stationary values for SO2 separation. Initially, the hold-up was sprayed with water to obtain stationary temperatures after cooling the particles and to conserve the used calcium hydroxide during the unsteady start-up phase. At the steady-state temperature the injection was suddenly switched to suspension. The SC>2-concentration at the outlet then decreased. The suspension consisted of lime hydrate (DIN 1060-CL90, DIN EN 12518) and water. The suspension injection had to be held constant until the SC>2-concentration was constant. After achieving steady state the injection was stopped, and this caused an increase in SC>2-concentration at the outlet up to the initial value. The same procedure was started after a few minutes in order to obtain a new measuring point at a higher suspension injection rate. 

The presence of 1-3% PVC in the feedstock stream results in the product fuel oil having a total chlorides level of 5000-10000 ppm. However at the same PVC levels the total chloride concentration in the diesel can be reduced to less than 10 ppm by the addition of lime hydrate according to the following reaction ... 

Lime, fine with tendency to pack Lime, hydrated... 

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