Conversion of hydrocarbon-contaminated particulate soil and/or rock to fertile soil

Abstract

A mixture of hydrocarbons with particulate rock and/or soil that is incapable of sustaining growth of erosion retarding plants can be converted to soil that is capable of sustaining such plant growth by blending the mixture with particulate biomass, and/or with particulate carbonates, hydroxides, and/or oxides of calcium and/or magnesium to produce a compostable aggregate and then exposing suitable piles of the compostable aggregate to the natural atmosphere for a sufficient time to cause the conversion of the aggregate to fertile soil

1 . A process for converting an infertile mixture of hydrocarbons with particulate soil, rock, or both rock and soil, said infertile mixture being free of plant growth-inhibiting concentrations of water soluble salts, to soil capable of sustaining growth of plant species that reduce the tendency of soil in which they grow to undergo erosion by movement of a fluid over the surface of the soil, said process comprising operations of: 
 (I) blending said infertile mixture with at least one of: 
 particulate biomass and  
 particulate material selected from the group consisting of the oxides, hydroxides, and carbonates of calcium and magnesium and mixtures of any two or more thereof  
 to generate a compostable aggregate in which the ratio by mass of organically bonded carbon to organically bonded nitrogen in the compostable mixture is not more than 500:1.00 and the ratio by mass of total organic chemical substances to total inorganic chemical substances exclusive of water in the compostable aggregate is at least 0.10:1.00;  
   (II) forming from said compostable aggregate and, optionally, additional water, at least one pile of the compostable aggregate that is supported by a base and has an exterior surface in contact with the natural atmosphere; and    (III) aging the pile or piles forming in operation (II) as recited above in contact with the natural atmosphere until the ratio by weight of organically bonded carbon to organically bonded nitrogen within the pile is not greater than 20:1.0,    whereby the aged pile or piles become said soil capable of sustaining growth of plant species that reduce the tendency of soil in which they grow to undergo erosion by movement of a fluid over the surface of the soil.    
     
     
         2 . A process according to  claim 1 , wherein particulate biomass is used in operation (I) as described above, no unnatural external source of mechanical or hydraulic energy is used during aging operation (III) to increase the flow of air into the interior of said pile or piles, and each said pile has a shape and size such that the area in square feet of the pile's surface in contact with the natural atmosphere has a ratio to the pile's volume in cubic feet that is from 0.10:1.00 to 0.75:1.00.  
     
     
         3 . A process according to  claim 2 , wherein the biomass blended in operation (I) consists of particles with an average largest particle linear dimension that is from 3.0 to 8.0 centimeters.