Lime hydrate and lime hydrate slurry with improved reactivity for water purification

Abstract

A hydrated lime product which can be provided to an end user in dry form and which can be formed into a slurry which will comprise lime hydrate with sufficiently increased reactivity over that of traditional hydrated lime slurries to be competitive in reaction time with on-site produced slaked lime slurries.

1 . A calcium hydroxide slurry comprising:
 calcium hydroxide particles having a reactivity of less than 15 seconds suspended in water;   wherein the reactivity is the amount of time it takes the calcium hydroxide particles to neutralize in citric acid, the citric acid having a mass greater than 10 times the mass of the calcium hydroxide particles.   
     
     
         2 . The slurry of  claim 1  wherein the reactivity is less than 10 seconds. 
     
     
         3 . The slurry of  claim 1  wherein the reactivity is less than 8 seconds. 
     
     
         4 . The slurry of  claim 1  wherein the reactivity is less than 4 seconds. 
     
     
         5 . The slurry of  claim 1  wherein the reactivity is less than 3 seconds. 
     
     
         6 . The slurry of  claim 1  wherein:
 90% percent of the calcium hydroxide particles are less than or equal to about 10 microns and greater than or equal to about 4 microns; and 
 a ratio of a size of particle 90% of the calcium hydroxide particles are below to a size of particle 10% of the calcium hydroxide particles are below is less than about 8. 
 
     
     
         7 . The slurry of  claim 1  wherein the calcium hydroxide particles have a BET surface area of about 18 m 2 /g or greater. 
     
     
         8 . The slurry of  claim 1  wherein the calcium hydroxide particles have a BET surface area of about 20 m 2 /g or greater. 
     
     
         9 . The slurry of  claim 1  wherein the calcium hydroxide particles have a BET surface area of about 30 m 2 /g or greater.