WO1992015098A1

WO1992015098A1 - Solidification of organic waste materials in cement

Info

Publication number: WO1992015098A1
Application number: PCT/US1992/001276
Authority: WO
Inventors: John E. Noakes
Original assignee: Noakes John E
Priority date: 1991-02-21
Filing date: 1992-02-18
Publication date: 1992-09-03

Abstract

A process for solidifying organic waste in cement for transport and storage in solid form comprises the steps of dispersing the organic waste in water containing a cationic amine as an emulsifier, mixing the resulting emulsion with cement without breaking the emulsion, casting the resulting mixture in a form and allowing it to solidify, and storing the solidified form in a waste disposal site. In a preferred embodiment of the process, a particulate material with a negative surface charge is included in the mixture of cement and emulsion to neutralize positive charges on the cationic emulsifier and the cement. An alcohol or glycol may be included in the emulsion to enhance the holding power and the integrity of the structure of the emulsion by controlling size and uniformity of emulsion particle size. The process is applicable to organic wastes such as waste oils, halogenated solvents, non-halogenated solvents, pesticides, herbicides, liquids and sludges containing heavy metals, and radioactive mixed wastes.

Description

Solidification of Organic Waste Materials In Cement

Field Of The Invention

The present invention relates generally to the disposal and storage of organic waste in cement, and more particularly, to the solidification of organic waste in a cement product which is not susceptible to leaching and which has high compressive strength.

Background Of The Invention

The federal government controls and dictates the regulation of the nation's hazardous waste through major laws. The Resource Conservation and Recovery Act (RCRA) 1976 and its 1984 amendments, regulate and manage the disposal of currently generated waste. The Comprehensive Environmental Response, Composition and Liability Act (Superfund) of 1980 directs its attention to financing cleanup of abandoned waste disposal sites. These two laws are primarily directed to industry which generates 99% of the nation's hazardous waste as residual by-products. It is estimated that by 1990 this level of hazardous waste production will reach 280 million metric tons (MMT) and will cost many billions of dollars to meet federal compliance standards for safe disposal.

The Environmental Protection Agency (EPA) has been charged by the federal government with enforcing laws for disposing of hazardous waste. This agency has over 400 specific waste streams listed that require regulation and which fall under broad categories such as waste oil, halogenated solvents, non- halogenated solvents, pesticides and herbicides, metal liquids and sludges, radioactive liquids and solids, mixed waste, etc. Of these many waste streams, it is currently estimated that nearly 90% are managed at the industrial site with no more than 10% being shipped off-site for treatment and disposal. New RCRA laws coming into effect will greatly increase stricter operation of landfills and surface impoundments and will include such requirements as double liners, ground water monitoring, leak detection and leachate collection. It is estimated that these new rules will encourage industry to seek new technology such as incineration, chemical oxidation and chemical stabilization rather than to choose to operate under rigorously enforced landfill operations. Incineration and chemical oxidation methods have in the past not met with public acceptance due to the possibilities of air pollution during their operation. Chemical stabilization, on the other hand, has not suffered this stigma and has the added advantage of being utilized on-site as end pipe treatment allowing the waste to be solidified for safer transport and acceptable landfill disposal. Of the various stabilization techniques being utilized and in development today, encapsulation and solidification methodology holds great promise.

Objects And Summary Of The Invention It is a primary object of this invention to provide an improved process for solidifying a broad range of organic wastes in cement (for transport and storage) which permits the loading of a relatively large amount of organic waste into any given amount of cement. In this connection, a related object of the invention is to provide such a process which is applicable to waste oils, halogenated solvents, non- halogenated solvents, pesticides, herbicides, liquids and sludges containing heavy metals, and radioactive mixed wastes.

It is another important object of this invention to provide such a solidification process which results in a solid product which has high compressive strength and a low leaching rate of the organic material from the solidified mass, so that the material can be safely deposited in a waste disposal site for solid wastes.

It is a further object of this invention to provide an improved organic waste solidification process which produces extremely stable emulsions that can be readily mixed with cement without breaking phase, and that provide extremely strong bonding with the cement matrix upon solidification.

A still further object of this invention is to provide an improved organic waste solidification process which requires only a small amount of emulsifier.

Other objects and advantages of this invention will be apparent from the following detailed description and the working examples. In accordance with the present invention, the foregoing objectives have been realized by providing a process for solidifying organic waste in cement for transport and storage in solid form by dispersing the organic waste in water containing a cationic amine as an emulsifier, mixing the resulting emulsion with cement without breaking the emulsion, casting the resulting mixture in a form and allowing it to solidify, and storing the solidified form in a waste disposal site. This process enables a large quantity of organic waste to be loaded into any given amount of cement, and produces a solidified mass which has high compressive strength and a low leaching rate. This process also requires only a small amount of the emulsifier.

In a preferred embodiment of the invention, the emulsion also includes a paniculate material with a negative surface charge to neutralize the like positive charges on the cationic-amine emulsifier and the cement thereby enhancing their bonding. Particular materials suitable for this purpose are siliceous materials such as fly ash.

In a modified embodiment of the process, the emulsion also includes an alcohol or glycol used to control emulsion particle size to enhance the holding power, thereby permitting even larger quantities of the organic waste to be solidified with the cement, and to enhance the integrity of the structure of the emulsion. Suitable materials for this purpose are methanol, ethanol, propanol, butanol and ethylene glycol.

Detailed Description Of Preferred Embodiments While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof will be described in detail, by way of example, herein. It should be understood, however, that it is not intended to limit the invention to the particular forms disclosed. On the contrary, the intention is to cover all modifications, equivalents and alternatives following within the spirit and scope of the invention as defined by the appended claims.

In the preferred embodiment of the process of this invention, an emulsion is formed by mixing a cationic amine with water and the organic waste, with the optional addition of an acid if the amine has not been previously pH neutralized. Normally the water and amine are pre-mixed, and then the organic waste is added to the water-amine mixture and vigorously stirred until an emulsion is formed, but amine can be directly mixed with the organic phase and water added to form the emulsion. The stirring is preferably carried out in a rotary mixer. The organic waste is normally in a liquid form, but when the waste includes solids such as uranium ore, the solid material should be in a finely pulverized state capable of being suspended in a water-amine emulsion.

There are many commercial cationic amines which are useful in the encapsulation process of the present invention. Examples of such commercial compounds are Εthoquad", "Redicotte", Ε-ll", "Trinoram S^M, and "Dinoram S.^M The cationic amines prefened for this work are made by Sherex Chemical Company, Inc., and include the cationic amine emulsifiers described in U.S. Patent No. 3,97535. A specific slow-set cationic amine emulsifier designated "Arosurf AAθT" was selected for use in the examples to be described below.

Ether single amines (monoamines) or multi amines (polyamines) may be used as emulsifying agents in the process of this invention for the formation of the oil-in-water emulsion. The physical and chemical properties of the organic waste material to be emulsified will dictate the desired combination of amines to be used. Organic waste materials to be emulsified may best be categorized into two broad groups of materials which are described by their affinity or ability to mix with an aqueous phase to form an oil-in-water emulsion.

Organic waste materials of high molecular weight possessing few, if any, functional groups that would enhance their interaction or hydration with an aqueous phase are best treated using a spectrum of amines of elevated carbon numbers. These amines are required to perform the most difficult task and include a broad group of amine compounds such as primary amines having the formula R¹NH₂ where R¹ is a straight or branched chain aliphatic group including from 2 to 22 carbon atoms (such as oleyl amine), primary ether amines having the formula R^ (CH₂)₃NH₂ where R² is a straight or branched chain aliphatic group including from 2 to 15 carbon atoms (such as C-12 to C-15 ether amine), secondary amines having the formula R³NHR⁴ where each of R³ and R⁴ is a straight or branched chain aliphatic group including 2 to 18 carbon atoms (such as ditridecyl amine), tertiary amines having the formula R⁵ ₃NR⁶N (CH₂)₂ R⁷ ₂NCH₃ where each of R⁵, R⁶ and R⁷ is a straight or branched chain aliphatic group including from 2 to 18 carbon atoms (such as tri (isooctyl) amine), fatty diamines having the formula R⁸NH (CH₂)₃NH₂ where R⁸ is a straight or branched chain aliphatic group including from 2 to 18 carbon atoms (such as oleyl diamine), and ether diamines having the formula R⁹0 (CH₂)₃ NH (CH₂)₃ NH (CH₂)₃ NH₂ where R⁹ is a straight or branched chain aliphatic group including from 1 to 15 carbon atoms. Organic waste materials of low molecular weight possessing functional groups that enhance their interaction with an aqueous phase are best treated with amines of lower carbon numbers. These amines have a tendency to be less complex in makeup and are made up of aliphatic, alkylene and alkanol structures with an R range from C-l to C-10. Such amines that fit this category are dimethylamine and triethylamine, ethylenediamine and phenylamine, and mono and di ethanolamine. Since most organic wastes to be emulsified are a combination or mixture of many waste streams, it is necessary in many cases to use a combination of amines (polyamines) to obtain the necessary physical and chemical properties for emulsion formation. In the formation of the emulsion it may be advantageous to use additives to further enhance emulsion formation. The pH of the amine is preferably neutral at the time of mixing with the cement.

The amine may be pre-neutralized, or it may be neutralized by the addition of acid prior to or during the formation of the emulsion. A secondary amine may also be used to maintain the pH near the prefeπed neutrality after the addition of an acid and before the mixing of the organic material.

One of the advantages of the process of this invention is that relatively small amounts of the emulsifier, i. e., the cationic amine, are required to form the desired emulsion. It is prefeπed that the amine be less than 2% by volume of the water-amine-waste emulsion, and in many applications the amine can be less than 1% of that emulsion. As will be described in more detail below in connection with the working examples, the amount of amine needed to form an emulsion from any particular combination of materials can be determined prior to actual mixing of the materials, thereby avoiding the use of excess amounts of emulsifier which can weaken the emulsion.

Another advantage of this process is that it permits the emulsion to be highly loaded with the organic waste material. In the prefeπed process the water- amine-waste emulsion contains a greater volume of organic waste than water, and in many applications the volume ratio of the organic waste to the water can be 2:1, 3:1 or even higher.

After the waste-containing emulsion has been formed, that emulsion is mixed with an amount of cement chosen to provide the desired weight ratio of cement to water. This ratio is typically about the same as described in the Noakes patent 4,416,810, namely, 100 parts by weight of cement for each 30 to 40 parts by weight water, but since the organic to water ratio using cationic amines has been found to be much higher, considerably more organic waste can be encapsulated than previously thought possible.

After the cement has been blended with the emulsion, the resulting mixture can be poured into any desired form, such as a mold or drums of varying volume, and allowed to solidify. The solidified mass can then be transported and stored in the forming container, or it can be removed from the form and stored as a self- supporting mass.

To evaluate the effectiveness of cationic amines in forming oil-in-water emulsions using organic solvents, emulsions made with the Triton X-100" nonionic surfactant described in Noakes U.S. Patent No. 4,416,810 were compared with like oil-in-water emulsions using the cationic amine "Arosurf AA-37" as the emulsifier (Table I). Toluene was the organic waste material in both emulsions. When the emulsion capabilities of the two emulsifiers were compared, it was found that the cationic amine emulsifier required approximately 1/10 the amount of emulsifier used in the Triton mix, and the cationic amine was able to hold considerably more toluene in the emulsion without breaking into two phases on mixing with cement. In fact, no upper limit on the ratio of toluene-in-water cationic emulsion was realized in testing up to a ratio of 2.63. The first column of Table L showing the Triton response, is identical to that shown in the "B" series of the first table in the Noakes patent 4,416,810.

The procedures used for making up the water-toluene-nonionic surfactant emulsions are described in the Noakes patent 4,416,810. The procedure used for making up the toluene-water-cationic amine emulsion was as follows: "Arosurf AA-37" was purchased as a fully pH-neutralized cationic amine, so that no acid was needed in the mixture; the amine was added to the water and stiπed; the toluene was added to the amine-water mixture in a blender at 2000 rpm and stiπed for 3 to 4 minutes; and the resulting emulsion was blended with cement and then poured into a mold to harden. To evaluate the compressive strengths of the various mixes, the amine- toluene-water cement mixes were poured into standard 3" x 6" molds (cylindrical molds having a diameter of 3 inches and a height of 6 inches). After 28 days of curing, testing was carried out in a Baldwin Universal Testing Machine having a 400,000 lb. capacity to determine the maximum compressive loads for cylindrical samples from each of the different mixtures. Each sample was weighed to check uniformity; each cylinder was measured to determine its cross-sectional area; each cylinder was capped with a sulfur compound to assure that the cylinder ends were flat and parallel so that compressive testing would provide uniform stress; and each cylinder was loaded in compression until failure in the Baldwin Universal Testing Machine. The maximum loads were divided by the area of the cylinder to give the ultimate compressive strength for each sample. The resulting data is recorded in Table n.

It can be seen from Tables I and II that the cationic amine produced emulsions with considerably higher holding capacity for the organic phase, that only 1/10 the amount of emulsifier was needed as compared with the nonionic surfactant, and that the final solidified cement samples were superior in structural integrity.

One of the advantages of the process of this invention is that a simple graph of the type illustrated in Graph I can be used to accurately predict the amount of amine needed to optimize the emulsion reaction. This avoids overloading the emulsifier in the emulsion action, as illustrated by the Triton emulsifier, is so that it is able to better encapsulate with near-stoichiometric levels of waste. The data in Graph I was compiled from Table I. For this particular application (AA-37 amine and toluene), the optimum amount of amine can be determined from the equation:

Amine Needed (ml) = 0.12 exp (0.018 x toluene (ml)) A particularly useful additive for the emulsions of this invention is a paniculate material with a negative surface charge, to neutralize like positive charge repulsion on the cationic emulsifier and the cement. Siliceous materials such as fly ash are particularly useful for this purpose. Fly ash is both abundant and inexpensive. The composition of a typical coal fly ash is presented in Table m, from it can be seen that the fly ash has a high silica content.

To evaluate the effect of adding a negative surface-charged component to the aqueous cationic amine-toluene emulsion (during its formation prior to mixing with the cement), a series of tests were conducted with fly ash added at the time of make up of an aqueous amine-toluene emulsion. The amount of fly ash added was calculated as a percent of the weight of organic solvent in the emulsion. For example, to produce a 25% fly ash mixture, as calculated from the A-6 mixture in Table II (2:1 toluene.-water with 13 ml AA-37), 128 ml of toluene x .866 g/ml (toluene density) = 110 g x .25 (percent) = 28g of fly ash was added. Table IV shows the structural integrity of cement cylinders of the A-6 composition cast in 3" x 6" cylinders. Measurements were made with the same equipment previously described to produce the data in Table π. The data in Table IV shows that the most optimum content of fly ash is 75% wt/wt of organic solvent. These samples were prepared using the A-6 formula with a 2:1 ratio of toluene and water, and 13 ml AA-37 mixed in a Waring blender for 2-3 minutes at 2000 rpm. The resulting emulsion was mixed with fly ash which had been sieved to pass through a 200 mesh screen. Upon mixing the emulsion with the fly ash, air entrapped bubbles in the emulsion were released with no phase separation. The mixture was then blended with cement and poured into a 3" x 6" mold for solidification. After 28 days these cylinders were tested for rupture pressure.

In order to evaluate the degree of teachability of the toluene encapsulated in the cement cylinders of varying fly ash content, a series of cement cylinders were made up as shown in Table V and subjected to leach testing after 28 days of curing. Four 7-day leach tests were conducted on the cylinders which had fly ash contents ranging from 0 to 100% in 25% increments. Each test ran for 7 days at which time a toluene analysis of the aqueous leachate was made, and the next 7- day leach period was performed with new water. In this way, a 28-day leach test was conducted in four 7-day increments.

The procedure followed for determining the liquid release of toluene solvent during aqueous leaching was to place each cylinder in a 4000 milliliter volume sealable container which contained 1000 milliliters of distilled water. This volume of water was selected as it fully covered the cylinders. The containers were also uniquely designed so as to allow syringe extraction of the water without opening to the atmosphere.

Aqueous leaching of the sold waste cylinders was carried out of for multi- successive seven-day leach periods. After each seven days, a 40-milliliter water sample was collected for measurement by gas chromatography.

Analyses were carried out by the University of Georgia Cooperative Extension Pesticide Laboratory using a Tracor model 540 Gas Chromatograph equipped with a flame ionization detector and a FFAP glass packed column. Samples were run isothermally at 35° and 300° C, respectively, using a nitrogen gas carrier at a flow rate of 10 milliliters per minute. Concentration levels of the leached toluene in the liquid and gaseous samples were determined by comparison with known standards. The data collected from the teachability studies is tabulated in Table V. Table V shows that the 75% fly ash had the best capability to hold the toluene solvent in the cement throughout the 28-day leach period and matches well with the structural integrity data at the 75% fly ash level in Table IV.

Mono and poly hydroxyl additives can be used to slow the hydration time and thereby retard the solidification of the waste-encapsulating cement mixtures. The advantages realized in using such additives to the cationic amine emulsion formulation are multifold. First, the smaller size of the micelles in the emulsion enables greater concentration levels of the organic phase to be emulsified. Secondly, the emulsion is more readily formed and is more durable in its ability to resist two-phase separation, especially when it is mixed with high-surface-area solids such as fly ash and cement. Also, only 0.1% by volume concentration levels of alcohol greatly reduce foaming of the emulsion during blending, which eliminates the problem of air entrapment into the emulsion which could be carried over to the cement.

A 2 to 1 by volume kerosene-iπ-water emulsion was made up using 128 ml of kerosene blended with a mixture of 64 ml H₂0 and 13 ml AA-37 cationic amine. Short carbon chain mono and poly alcohols were added at the 0.1%, 05% and 1.0% levels. All alcohols tested were mixed with the aqueous phase prior to forming the emulsion. Each of these emulsions was visually evaluated for micelle size, uniformity and distribution using a Zeiss microscope with 640x magnification, with each evaluation based on 15 or more observations. Particle sizes ranged from less than 1 micrometer to greater than 35 micrometers.

Table VI shows the results of these examples and indicates that the mono and poly alcohols greatly reduced the diversity and size of the micelle population making up the emulsion. Butanol at the 1.0% by volume level was only partially miscible and should be considered, as should higher carbon alcohols, best used when mixed with the organic phase prior to emulsion formation.

The following examples illustrate the excellent capability and wide versatility of the method of this invention for encapsulating in cement a wide spectrum of different industrially generated waste streams. Specifically, the following examples illustrate the encapsulation of (1) waste oils (kerosene), (2) non-halogenated hydrocarbons (benzene), (3) halogenated hydrocarbons

(chlorobenzene), (4) insecticides (aldrin), (5) heavy metal liquids and sludges (Pb, Cd, Zn ppts), and (6) radioactive mixed wastes (uranium ore and toluene).

Example 1 Kerosene was used as an example of the type of compound frequently found in the waste oil categoiy and was solidified in the following manner. A 2 to 1 by volume kerosene-in-water emulsion was made up by mixing 128 mL of kerosene with a mixture of 64 mL H₂0, 13 mL of AA-37 cationic amine, and 1 mL of isopropyl alcohol and blended in a Waring Blender for 3 to 5 minutes at 2000 rpm. The emulsion was mixed with 76 grams of fly ash for charge neutralization, and then the total mixture was blended with 200 grams of #2 type cement sieved to 200 mesh. The mixture was made in quantity, poured into a cylindrical mold having a diameter of 3 inches and a height of 6 inches, and cured for 28 days to a solid mass. The resulting cylinders were subjected to a 28-day aqueous leach test and a compressive stress test, with the results shown in Table Vπ. These results show only minimal release of kerosene from the cement cylinder through the 28-day leach period, and an acceptable load compressive stress of 3100 pounds.

Example 2 Benzene was selected as an example of a hydrocarbon compound frequently listed in the non-halogenated category. Again, as in Example 1, a 2 to 1 by volume benzene-in-water emulsion was made up by mixing 128 mL of benzene with a mixture of 64 mL of H₂0, 1.3 mL of AA-37 cationic amine and 2 mL of isopropyl alcohol and blended in a Waring blender for 3 to 5 minutes at 2000 rpm. The emulsion was mixed with 76 grams of fly ash for cationic charge neutralization, and the resulting mixture was blended with 200 grams of #2 cement. The cement mixture was poured into a cylindrical mold and cured for 28 days to a sohd mass. The resulting cylinders were subjected to a 28-day aqueous leach test and a compressive stress test, with the results shown in Table VIII. These results show only minimal amounts of benzene (in the ppm level) were released during the 28-day leach period, and a good load compressive stress of 13,000 pounds. Example 3

Chlorobenzene was selected as typical of a compound that would be listed in the halogenated hydrocarbon category. Again, a 2 to 1 by volume chlorobenzene-in-water emulsion was made by mixing 128 mL of chlorobenzene with a mixture of 64 mL H₂0, 1.3 mL AA-37 cationic amine and 1 mL isopropyl alcohol and blended in a Waring blender for 3 to 5 minutes at 2000 rpm. The resulting emulsion was mixed with 76 grams of #2 cement. The cement mixture was poured into a cylindrical mold having a diameter of 3 inches and a height of 6 inches and cured for 28 days to a solid mass. The resulting cylinders were subjected to a 28-day aqueous leach test and a compressive stress test, with the results shown in Table IX. These results show only minimal amounts of chlorobenzene were released during the 28-day leach period and a good load compressive stress of 14,000 pounds. Example 4

Aldrin, a chlorinated insecticide which is no longer commercially used because of excessive toxicity properties, was selected as typical of a compound to appear in the insecticide waste category. A 2 to 1 by volume kerosene-in-water emulsion containing this compound was made up in the following manner. A 10% wt/wL solution of aldrin in kerosene was made up by dissolving 11.4 grams of aldrin in 128mL of kerosene. An emulsion was then formed by mixing the resulting solution with 64 mL H₂0, 1.8 mL AA-37 cationic amine, and 1 mL isopropyl alcohol and blending in a Waring blender for 6 to 8 minutes at a speed of 2000 rpm. The emulsion was mixed with 82 grams of fly ash for cationic positive charge neutralization, and the total mixture was blended with 200 grams of #2 cement. The cement mixture was then poured into a cylindrical mold having a diameter of 3 inches and a height of 6 inches and cured for 28 days to a solid mass. The resulting cylinders were subjected to a 28-day leach test and a compressive stress test, with the results shown in Table X. These results showed only minimal aldrin release for the 28-day test period, and an acceptable compressive test value of 3800 pounds.

Example 5 A watery precipitate containing lead, cadmium, and zinc was made up to represent a heavy metal liquid-sludge material found in the metal liquid-sludge waste category. The sample preparation was carried out by making up a 3-liter aqueous solution containing 1000 ppm each of the three metals. The solution was acidified to a pH of 5 to 6, and a complexing compound (Triplex) was added to form a precipitate which removed the metals from solution with >99% efficiency, forming a coagulated watery metal-organic precipitate.

This quasi liquid-sludge mixture representing a volume of approximately 192 mL was mixed with 64 mL H_zO, 1.8 mL AA-37 cationic amine and 1 mL isopropyl alcohol and formed into an emulsion by blending in a Waring blender for 6 minutes at 2000 rpm. The resulting emulsion was mixed with 77 grams of fly ash for charge neutralization, and the total mixture was then blended with 200 grams of #2 cement. The cement mixture was poured into a cylindrical mold having a diameter of 3 inches and a height of 6 inches, and cured for 28 days to a solid mass. The resulting cylinders were subjected to a 28-day aqueous leach test and a compressive stress test, with the results shown in Table XI. These results show no detectable leach of heavy metals during the 28-day test period, and a high compressive test value of 24,700 pounds, showing excellent integrity. Example 6

A mixture of uranium ore and toluene was selected as perhaps typical of what one would find in a radioactive mix waste category. The encapsulation of this mixture was carried out by forming a 2 to 1 by volume toluene-in-water emulsion by mixing 128 mL of toluene with a mixture of 64 mL H₂0, 1.5 mL AA- 37 cationic amine and 1 mL of isopropyl alcohol and blending in a Waring blender for 5 minutes at a speed of 2000 rpm. The resulting emulsion was mixed with 76 grams of uranium ore (0.4% U) of high alumino-silicate which had been crushed and sieved to a 200 mesh particle size. Upon mixing the emulsion with the ore, the high silicate content of the ore acted to neutralize the cationic amine charge in a similar manner to that of the fly ash. This mixture was blended by constant stirring with 200 grams of #2 cement, and the total mixture poured into a cylindrical mold having a diameter of 3 inches and a height of 6 inches, for curing. After 28 days the cement had solidified to a solid mass. The resulting cylinders were subjected to a 28 day aqueous leach test and a compressive stress test with the results shown in Table XII. These results show no detectable uranium leached from the cylinder during the 28-day leach period and an exceptionally high compressive test of 13,900 pounds, indicating good structural integrity.

TABLE I.

Comparative Formulation Using Triton 100 and Arosurf AA-37 for Cement-Toluene Encapsulation

Triton Ratio Arosurf AA-37 Toluene/H₂0

B-3 200 g cement 48/64 (0.75) 48 ml toluene 4 ml Triton 64mlH₂0

B-4 200 g cement 56/64 (0.88) A-2 200 g cement 56 ml toluene 56 ml toluene 4 ml Triton 03 ml AA-37 64mlH₂0 64mlH₂0

B-5 200 g cement 64/64 (1.00) A-3 200 g cement 64 ml toluene 64 ml toluene 4 ml Triton 0.4 ml AA-37 64mlH₂0 64mlH₂0

B-6 Micelle failure 88/64 (1.38) A-4 200 g cement

88 ml toluene 0.7 ml AA-37 64mlH₂0

112/64 (1.75) A-5 200 g cement

112 ml toluene 0.9 ml AA-37 64mlH₂0

128/64 (2.00) A-6 200 g cement

128 ml toluene 13 ml AA-37 64mlH₂0

152/64 (238) A-7 200 g cement 152 ml toluene 1.9 ml AA-37 64mlH₂0

168/64 (2.63) A-8 200 g cement 168 ml toluene 2.5 ml AA-37 64mlH₂0 TABLE II.

Average Ultimate Compressive Stress Tests of Cement Cylinders Containing Toluene and Triton or Arosurf AA-37 Dispersant

Sample Size: 3-inch diameter for 6-inch cylinder height

TABLE III.

Typical Chemical Parameters of Coal Fly Ash

Typical Range Element/Parameter of Concentration

1. Silica (Si0₂) 50-60%

Amorphus 39-56%

Crystalline 2-4%

2. Alumina (A1₂0₃) 17-25%

3. Iron oxide (Fe^) 3-30%

4. Calcium oxide (CaO) 3.8-6.4%

5. Magnesium oxide (MgO) 1.0-2.0%

6. Potassium oxide (K₂0) 05-1.9%

7. Titanium dioxide (Ti0₂) 0.5-0.7%

8. Sulfur trioxide (S0₃) 0.1-0.5%

9. Phosphorous pentoxide (P₂O_s) 0.5-0.75%

10. pH 4-8

TABLE IV.

Average Ultimate Compressive Stress Tests on Cement Cylinders of A-6 Chemical Composition with Varying Fly Ash (FA) Content

28 Day Aqueous Leach Test of Cement Cylinders of A-6 Chemical Composition with Varying Fly Ash (FA) Content

% Fly Ash calculated on the percent wt./wt. ratio of FA/organic constituent (toluene).

Detection Limit for toluene 50 parts per billion (ppb). TABLE VI.

Microscopic Particle Size Analyses of Kerosene in Water Cationic Amine AA-37 Emulsion 5 with Varying Concentrations of Short

Chain Alcohols in Aqueous Phase

Emulsiop + Alcohol Largest Particle Medium Particle Smallest Particle 10 A-6 Kerosene Size (am) Size (μm) Size (μm)

+ Water + AA-37 = E

1. E + zero alcohol 315 9.79 25

15

25 2.1 42

2.1 <1.0 <1.0

3.15 <1.0 0.84

2.1 <1.0

45

14. E + ethylene glycol (.1%) 105 336 7.0

15. E + ethylene glycol (5%) 105 434 2.1 50 16. E + ethylene glycol (1.0%) — ~- --

Emulsion (E) made up as blended mixture of 128 mL kerosene, 13 mL AA-37 amine in 64 cc H₂0; alcohol added to aqueous phase in 1-5-10% of total emulsion 5 volume.

All measurements made in micrometers (μm).

Magnification of Zeiss Microscope (640x) 0

Sample number evaluated where n = 15 for each analysis.

GC: Gas Chromatography

Mi mum Detectionlimit (MDL): 0.2 parts per million (ppm)

II. Compressive Stress Test

Load Capacity: 3,100 lbs.

TABLE VIII.

28 Day Aqueous Leach and Comp ressive Stress Test oonn BBeennzzeennee WWaassttee EEnnccaappssuullaatteedd^^{^} C Cement Cylinders

Chemical Analysis - GC

Leach period

Compound 7 dny 14 y 21 day 28 dav (ppm) (ppm) (ppm) (ppm)

Benzene 265 140.5 813 51.7

GC: Gas Chromatography

Minimum DetertionXimit: 05 parts per million (ppm)

π. Compressive Stress Test

Load Capacity: 13,000 lbs. TABLE IX.

28 Day Aqueous Leach and Compressive Stress Test on Chlorobenzene Waste Encapsulated Cement Cylinders

I. Chemical Analysis - GC

Leach period

Compound 7__dax 14 day 21 day 28 day (ppm) (ppm) (ppm) (ppm)

Chlorobenzene 16.3 5.47 4.0 2.15

GC: Gas Chromatography

Minimum Detection limit: 05 parts per million (ppm)

π. Compressive Stress Test

Load Capacity: 14300 lbs.

TABLE X

28 Day Aqueous Leach and Compressive Stress Test on Aldrin-Kerosene Waste Encapsulated Cement Cylinders

I. Chemical Analysis - (GC)

Leach period

Compound 7 day, 14 day_, 2,1 da ayy 2288_d day

(pp ) (ppm) (ppm *)) ( (PpΓpm)

Aldrin 3.96 0.74 0.43 0.19

GC: Gas Qiromatography Minimum Detectfonlimit (MDL): 0.1 parts per million (ppm)

π. Compressive Stress Test

Load Capacity: 3,800 lbs. TABLE XI.

28 Day Aqueous Leach and Compressive Stress Test on Heavy Metal (Zn, Cd, Pb) Sludge

Encapsulated Cement Cylinders

I. Elemental Analysis - (ICAP)

Leach period

Element fe 7 day_t 1 1,44 ddaayy da^y 2$ da;

»p*m) (ppm) (Ppm) >p J

Zinc <MDL <MDL <MDL <MDL

Cadmium <MDL <MDL <MDL <MDL

Lead <MDL <MDL <MDL <MDL

ICAP: Inductively Coupled Argon Plasma

Minimum Detection Limit (MDL): 0.5 parts per million (ppm)

Cadmium 0.10-200 ± 0.29 ppm

Lead 0.10-200 ± 1.99 ppm Zinc 0.05-200 ± 0.48 ppm

H. Compressive Stress Test

Load Capacity: 24,700 lbs.

TABLE XII.

28 Day Aqueous Leach and Compressive Stress Test on Uranium Ore Mixed Encapsulated Cement Cylinders

I. Elemental Analysis - (ICAP) Leach period

Element 7 day 14 day 21 day 28 day

(ppm) (ppm) (ppm) (ppm)

Uranium <MDL <MDL <MDL <MDL

ICAP: Inductively Coupled Argon Plasma

Minimum Detection limit (MDL): 05 parts per million (ppm) Uranium 1.00-600 ± 232 ppm

II. Compressive Stress Test Load Capacity: 13,900 lbs.

Claims

Solidification of Orgamc Waste Materials In CementCLAIMS:

1. A process for solidifying organic waste in cement for transport and storage in solid form, said process comprising the steps of dispersing the organic waste in water containing a cationic amine as an emulsifier, mixing the resulting emulsion with cement without breaking the emulsion, casting the resulting mixture in a form and allowing it to solidify, and storing the solidified form in a waste disposal site.

2. The process of claim 1 wherein a paniculate material with a negative surface charge is included in said mixture of cement and emulsion to neutralize positive charges on said cationic emulsifier and said cement.

3. The process of claim 2 wherein said particulate material is a siliceous material.

4. The process of claim 3 wherein said siliceous material is fly ash.

5. The process of claim 1 wherein an alcohol or glycol is included in said emulsion to enhance the holding power and the integrity of the structure of said emulsion by controlling size and uniformity of emulsion particle size.

6. The process of claim 1 wherein said alcohol or glycol is selected from the group consisting of methanol, ethanol, propane, butanol and ethylene glycol.

7. The process of claim 1 wherein said organic waste is selected from the group consisting of waste oils, halogenated solvents, non-halogenated solvents, pesticides, herbicides, liquids and sludges containing heavy metals, and radioactive mixed wastes.

8. The process of claim 1 wherein the pH of the water-amine-waste emulsion is essentially neutral.

9. The process of claim 1 wherein said organic waste is in the form of a liquid or finely divided particulate material capable of being suspended in said water-amine emulsion.

10. The process of claim 2 wherein said organic waste is an organic solvent, and said cement-emulsion mixture contains about 75% by weight particulate material based on the weight of said organic solvent.

11. The process of claim 1 wherein said emulsion of water, organic waste and cationic amine contains less than 2% by volume of the cationic amine.

12. The process of claim 1 wherein said emulsion of water, organic waste and cationic amine contains a greater volume of organic waste than water.

13. The process of claim 1 wherein the cationic amine is selected from the group consisting of primary amines having the formula R^αNH₂ where R¹ is a straight or branched chain aliphatic group including from 2 to 22 carbon atoms, primary ether amines having the formula R²0 (CH₂)₃NH₂ where R² is a straight or branched chain aliphatic group including from 2 to 15 carbon atoms, secondary amines having the formula R³NHR⁴ where each of R³ and R⁴ is a straight or branched chain aliphatic group including 2 to 18 carbon atoms, tertiary amines having the formula R⁵ ₃NR⁶N (CH₂)₂ R⁷ ₂NCH₃ where each of R⁵, R⁶ and R⁷ is a straight or branched chain aliphatic group including from 2 to 18 carbon atoms, fatty diamines having the formula R⁸NH (CH₂)₃NH₂ where R⁸ is a straight or branched chain aliphatic group including from 2 to 18 carbon atoms, and ether diamines having the formula R⁹0 (CH₂)₃ NH (CH₂)₃ NH (CH₂)₃ NH₂ where R⁹ is a straight or branched chain aliphatic group including from 1 to 15 carbon atoms.

14. The process of claim 1 wherein the ratio or organic waste to water in said emulsion is at least 3:1 by volume.

15. The process of claim 1 wherein said organic waste is a mixture of different materials, and said emulsifier is a mixture of different cationic amines selected to emulsify the different waste materials when mixed therewith in water.