Oil Shale Retort Water Research Articles

EFFECTS OF COD:SULFATE RATIO ON SULFATE REMOVAL FROM OIL SHALE RETORT WATER USING MICROBIAL FUEL CELLS

This paper reports the effects of COD:sulfate ratio on sulfate removal and electricity generation from oil shale retort water treatment using microbial fuel cells (MFCs). Field-collected retort water was augmented with organics to obtain a range of initial COD:SO42- ratios (0.5:1 to 2:1), and treated in two different MFC designs (tubular and two-chambered). The two-chambered MFCs exhibited COD and sulfate removal 1 to 2 orders of magnitude higher than those of the tubular MFCs. The tubular MFCs did not exhibit a significant dependence of sulfate removal on the COD:SO42- ratio while the two-chambered MFCs showed a positive trend. The tubular MFCs generated a maximum power density of 19 mW/m2 (COD:SO42-= 1.5:1), and the two-chambered MFCs produced 120 mW/m2 (2:1). The results suggest that organic carbon loading to the MFCs should be determined based on the sulfate concentration and reactor design to achieve optimal sulfate removal and electric power output.

POLYNUCLEAR AROMATIC COMPOUNDS IN COAL AND OIL SHALE WASTEWATER: AN ENVIRONMENTAL CONCERN

ABSTRACT A solvent refining coal liquefaction process recycle water (No. 3) from Du Pont, Washington, a true in-situ oil shale retort water (Omega-9) from Rock Springs, Wyoming, and a ten-ton unit simulated in-situ oil shale retort water (No, 16) from Laramie, Wyoming, were subjected to solvent extraction procedure and subsequent instrumental analysis including: (a) high performance liquid chromatography (HPLC) of polynuclear aromatics (PNA's) having more than four rings; (b) capillary gas chromatography (GC) of low molecular weight volatile PNA's; and (c) gas chromatography-mass spectrometry (GC-MS) for complementary identification of PNA's having functional and heterocyclic modifications. A total of 41 PNA's were identified. Identification of 28 PNA's in the coal derived water (No. 3) was attained, whereas that of the true in-situ retort water (Omega-9) and the simulated retort water (No. 16) were 24 and 18, respectively. Thirteen PNA's were found to be common to all three wastewater samples. Thirteen PNA's were exclusively found in sample No. 3 whereas that of samples Omega-9 and No. 16 were 8 and 4, respectively. It was estimated that the concentration of PNA's in all samples ranged from traces to 30.0 ppb.

Adsorption and microbial degradation of organic compounds in oil shale retort water

Studies were conducted to investigate the mechanisms of removal (adsorption and biodegradation) of organic compounds of environmental concern in a continuous retort water treatment cell (RWTC), in which a bed of solid wastes was irrigated with the retort water. The adsorption mechanisms were investigated in batch experiments. The results show that initial adsorption (40–90%) occurs very rapidly and is followed by slower adsorption (10–60%) until equilibrium is achieved after 200–300 h, the actual period depending on the initial concentration of total organic carbon (TOC) and the solid:solution ratio. The microbial species responsible for aerobic biodegradation within the treatment cell were identified. Fungi were dominant in the upper part of the cell. Bacteria of the genera Pseudomonas, Agrobacterium and Bacillus were dominant in the lower parts.

Isotherm studies on sorption of pyridine and quinoline onto Rundle spent shale

Single and binary adsorption of pyridine and quinoline from dilute aqueous solutions onto Rundle spent shale have been investigated in some detail. The results show that all of the isotherms are of the L-4 (Langmuir) type. There is insignificant competition between the two solutes during adsorption, particularly at low concentrations. This allows prediction of the bisolute adsorption behaviour using the single-solute Langmuir expressions. The results indicate that the spent shale behaves as a clay-like material and has potential as an adsorbent for the treatment of oil shale retort water. The results provide fundamental insight into the mechanisms likely to control the transport of N-heterocyclic compounds in spent shale dumps.

Growth of bacteria in an oil shale retort water by indigenous microorganisms.

Previous studies have shown that relatively high aerobic and anaerobic (or facultatively anaerobic) heterotrophic bacterial population densities occur as indicated by an increase in the turbidity of freshly filtered (0.4 ..mu..m) Omega-9 retort water after a few days incubation at room temperature. Growth of these microorganisms alters the nature and concentrations of dissolved organic and inorganic constituents. Bacteria are the only microorganisms known to have demonstrated a capacity to grow in undiluted Omega-9 retort water. Bacterial growth experiments are performed for a variety of reasons. In some situations microorganisms are cultivated to yield a specific product, as a protein source, or because their growth in a particular medium removes certain undesired constituents. Nutritional and physical parameters will often govern the rate at which growing microbial populations proliferate. It was considered important, therefore, to establish what rates of bacterial growth were occurring in the Omega-9 retort water by indigenous, mixed bacterial populations. The study reported here was devised to assess bacterial growth characteristics in an example retort water. Information of this type may have implications in 1) the development of biological treatment systems, 2) establishing hazard assessment and abatement criteria, and 3) in assessing the stability of research samples.

Applications of liquid chromatography with electrochemical detection to the analysis of oil shale process waters

The application of liquid chromatography with electrochemical detection for the selective analysis of organics in complex mixtures is described. Experimental conditions are given for the quantification of phenols, aromatic amines and certain heterocyclic bases related to piperidine and pyrrolidine, after preliminary separation into acidic, basic and neutral fractions. The technique is applied to the analysis of oil shale retort waters.

Oil shale retort water ammonia determination by titrimetry, phenate colorimetry, enzymatic analysis, and chromatographic fractionation/chemiluminescence

A statistical comparison was made of three modified standard methods and a new rapid estimator for determining ammoniac-N in oil shale retort waters. The modified standard methods were (1) distillation/acidimetric titration (automated), (2) phenate colorimetry, and (3) glutamate dehydrogenase enzymatic analysis. The fourth method, reverse-phase fractionation-combustion/chemiluminescence (RPF-C/Cl), used a reverse-phase chromatographic technique to separate polar from nonpolar nitrogenous compounds; combustion/chemiluminescence was then used to determine total-N in the polar fraction as a rapid estimate of ammoniac-N. Ammoniac-N for 12 retort waters ranged from 1 to 33 g/L. Precision was best for the titrimetric and colorimetric methods (relative standard deviations 0.01) across all waters only when titrimetry was compared with enzymatic analysis. The RPF-C/CL method gave the most rapid estimate ofmore » ammonia and would be useful for spot monitoring or range finding for the other methods.« less

Effect of ozonation and UV irradiation on biorefractory organic solutes in oil shale retort water

Biooxidation of oil shale process wastewaters in dispersed-phase cultures removed only 9-50% of the dissolved organic carbon. Attempts to promote biodegradation of the refractory carbon (predominantly aromatic amines) by physicochemical means met with little success. These included ultraviolet irradiation/ozonation, addition of activated carbon to dispersed-phase cultures, and use of fixed-film bioreactors.

Organic nitrogen determination in oil shale retort waters

Two new approaches were used to separate ammonia from various fractions of organonitrogen compounds in oil shale wastewaters, thereby permitting the application of a rapid, but unselective, method for total N determination (combustion/chemiluminescence) to the direct estimation of organic N. The first method uses reverse-phase chromatography to separate polar from nonpolar nitrogenous compounds. The second uses nonosmotic dissolved-gas dialysis to separate volatile from nonvolatile nitrogenous solutes. For 12 oil shale retort waters, correlation of the resulting measures of organic N against organic Kjeldahl nitrogen values gave correlation coefficients for the nonpolar and nonvolatile nitrogen values of 0.920 and 0.996, respectively. Relative standard deviations averaged 3.9%. Combining the two methods yielded higher estimates of organic N; correlation against organic Kjeldahl nitrogen yielded a correlation coefficient of 0.989. Organic N concentrations for the water measured by all four methods ranged from 15 to 5000 mg/L. These data showed, that on the average, at least one-half to three-fourths of the organic carbon was associated with nitrogen. 32 references, 2 figures, 3 tables.

Chemiluminescence vs. Kjeldahl determination of nitrogen in oil shale retort waters and organonitrogen compounds

The applicability of combustion/chemiluminescent nitrogen analysis to quantifying nitrogen in oil shale wastewaters and various representative chemical classes was demonstrated. Only azoxy compounds and those containing the pyrazole nucleus were not amenable to analysis. The majority of 56 compounds tested yielded from 90% to 110% of their theoretical nitrogen contents: enhanced recovery was found for nitrogen oxide salts. For 12 oil shale wastewaters, combustion/chemiluminescence gave total nitrogen values (1100-28800 mg/L) that did not differ statistically (P > 0.10) from those obtained by the time-consuming wet-chemical Kjeldahl method. The relative standard deviations for ten matrix or solvent effects were found. 28 references, 1 figure, 3 tables.

Anthracene bioconcentration in rainbow trout during single‐compound and complex‐mixture exposures

AbstractRainbow trout were exposed for 72 h to [14C]anthracene alone and [14C]anthracene in an oil shale retort water. Tissue levels of [14C]anthracene were analyzed at 24, 48 and 72 h to determine non‐steady‐state bioconcentration factors (BCFs), and uptake and depuration rates were calculated from anthracene disappearance in exposure waters and metabolite appearance in depuration waters. Uptake rates (14.6 to 16.9 h−1) were similar to previously reported values; however, depuration rates (0.00158 to 0.00188 h−1) were very low. Consequently, measured non‐steady‐state BCFs after 72 h (9,000 to 9,200) for anthracene were higher than expected, probably because fish were not fed and had low excretion rates. Measured and estimated anthracene BCFs were lower in retort water exposures than in single‐compound exposures because of slower uptake and faster depuration. We attribute slower uptake during retort water exposures to either decreased bioavailability of anthracene or rate‐limiting transport of contaminants from uptake sites to storage and processing sites. Induction of mixed‐function oxidases may have increased depuration from fish exposed to retort water. We conclude that bioconcentration of individual compounds from complex chemical mixtures may be difficult to predict based on single‐compound kinetics.

Identification and treatability of organics in oil shale retort water

Analysis by GC-MS of the process water derived from Fischer Assay retoring of oil shale from Rundle, Australia has provided positive identification of the major organic constituents present. This is the first detailed analysis of retort water from Australian oil shales and showed that the compounds ranged from being highly biodegradable to highly inhibitory and resistant to biological oxidation. The major classes of compounds found in a composited sample included normal carboxylic acids, alkyl pyridines, quinolines and cyclic saturated and unsaturated ketones. Separation of the retort water into its acid, base and neutral fractions was brought about by solvent extraction using methylene chloride. A series of treatability studies on the retort water confirmed the hypothesis that only a portion of the organic carbon was amenable to biological treatment. In addition, high ammonia levels further inhibited biological action. Adsorption of the retort water with activated carbon proved most successful in removing the non-biodegradable fraction of the organic species. Chemical oxidation by ozone does not appear attractive because it lacks the specificity of adsorption.

Constituent bioconcentration in rainbow trout exposed to a complex chemical mixture.

Classically, aquatic contaminant fate models predicting a chemical's bioconcentration factor (BCF) are based upon single-compound derived models, yet such BCF predictions may deviate from observed BCFs when physicochemical interactions or biological responses to complex chemical mixture exposures are not adequately considered in the predictive model. Rainbow trout were exposed to oil-shale retort waters. Such a study was designed to model the potential biological effects precluded by exposure to complex chemical mixtures such as solid waste leachates, agricultural runoff, and industrial process waste waters. Chromatographic analysis of aqueous and nonaqueous liquid-liquid reservoir components yielded differences in mixed extraction solvent HPLC profiles of whole fish exposed for 1 and 3 weeks to the highest dilution of the complex chemical mixture when compared to their corresponding control, yet subsequent whole fish extractions at 6, 9, 12, and 15 weeks into exposure demonstrated no qualitative differences between control and exposed fish. Liver extractions and deproteinized bile samples from exposed fish were qualitatively different than their corresponding controls. These findings support the projected NOEC of 0.0045% dilution, even though the differences in bioconcentration profiles suggest hazard assessment strategies may be useful in evaluating environmental fate processes associated with complex chemical mixtures. 12 references, 4 figures,more » 2 tables.« less

Quantitation of Carbon in Oil Shale Process Wastewaters: Coulometry Coupled with Ultraviolet-Peroxydisulfate and High-Temperature Oxidation

Abstract Wastewaters from the production of synfuels, in particular oil shale retort waters, present several major problems to various instrument configurations designed for carbon analysis. A carbon analyzer was fabricated from commercially available oxidation and detection units. Carbon oxidation occurred in an ultraviolet (UV) photochemical reactor using acid peroxydisulfate; quantitation of the evolved carbon dioxide was accomplished with an automatic coulometric titrator. This new design eliminated the problems of (1) instrument downtime caused by fouling of high-temperature combustion catalysts and corrosion of furnace combustion tubes, (2) limited linear dynamic range and upper detection limit (namely, infrared detection), and (3) frequent detector calibration (namely, infrared and flame ionization detection). The UV-persulfate/coulometric titration carbon analyzer was compared statistically with a high-temperature combustion system that is suitable for use with an ASTM method on the basis of (1) the accuracy and precision of recovery of total dissolved carbon (TDC) and dissolved organic carbon (DOC) for nitrogen heterocycles, which were of primary interest because of their preponderance in oil shale process waters and their reported resistance to certain oxidation methods, and (2) the precision of TDC and DOC determinations for nine oil shale process wastewaters. Several qualitative considerations are discussed for both analyzers, including ease of operation, instrument downtime, and maintenance costs.

Determination of total solutes in synfuel wastewaters

Efforts to investigate both lyophilization and the measurement of colligative properties as an indication of total solute content are described. The objective of the work described is to develop a method for measuring total dissolved material in retort wastewaters which is simple and rugged enough to be performed in a field laboratory in support of pollution control tests. The analysis should also be rapid enough to provide timely and pertinent data to the pollution control plant operator. To be of most value, the technique developed also should be applicable to other synfuel wastewaters, most of which contain similar major components as oil shale retort waters. 4 references, 1 table.

Partition chromatography-high-performance liquid chromatography facilitates the organic analysis and biotesting of synfuels

Partition chromatography (Sephadex LH-20 or C 18-partition) followed by high-performance liquid chromatography facilitated the organic and mutagenic characterization of synfuel samples. The mutagens in oil shale retort waters were polar, whereas those in a shale oil ranged from moderately polar to polar. In contrast, the mutagens in an solvent refined coal-II (SRC-II) distillate blend were primarily moderately polar. The mutagens in an SRC-I process solvent were both less polar and less heterogeneous than those of an SRC-I solid product. Known mutagens (primary aromatic amines and aza-polynuclear aromatic hydrocarbons) were identified in the SRC-I and SRC-II samples but not in the shale oil and retort waters.

Determination of polar organic solutes in oil-shale retort water

A variety of analytic methods were used to quantitatively determine polar organic solutes in process retort water and a gas-condensate retort water produced in a modified in situ oil-shale retort. Specific compounds accounting for 50% of the dissolved organic carbon were identified in both retort waters. In the process water, 42% of the dissolved organic carbon consisted of a homologous series of fatty acids from C/sub 2/ to C/sub 10/. Dissolved organic carbon percentages for other identified compound classes were as follows: aliphatic dicarboxylic acids, 1.4%; phenols, 2.2%; hydroxypyridines, 1.1%; aliphatic amides, 1.2%. In the gas-condensate retort water, aromatic amines were most abundant at 19.3% of the dissolved organic carbon, followed by phenols (17.8%), nitriles (4.3%), aliphatic alcohols (3.5%), aliphatic ketones (2.4%), and lactones (1.3%). Steam-volatile organic solutes were enriched in the gas-condensate retort water, whereas nonvolatile acids and polyfunctional neutral compounds were predominate organic constituents of the process retort water. 28 references.

ADSORPTION OF ORGANICS FROM A TRUE IN-SITU OIL SHALE RETORT WATER ON ACTIVATED CARBON IN PACKED BEDS

The adsorption of a true in-situ oil shale retort water on activated carbon at 278 and 298 K was studied in batch experiments and in packed beds with continuous liquid flow. The isotherms were nonlinear over the liquid concentration 0 to 875 mg/1. Breakthrough curves were obtained in packed bed experiments as a function of bed length, particle size, and liquid velocity. A differential approach was used to calculate the mass transfer coefficients and the rates of adsorption. Also the breakthrough curves were analyzed to establish the relative importance of the various individual mechanisms that contributed to the overall adsorption process.

Chronic effects of ammonia-stripped oil shale retort water on fishes, birds, and mammals

Commercial oil shale development of the Green River Formation in Colorado, Utah, and Wyoming will probably take place within the next decade. Equal volumes of oil and retort water are expected to be produced using in situ oil shale processing. Research has been done on the acute toxicity of retort water to fish and mammals. The acute effect on fish is gill hyperplasia, primarily from the irritating effect of ammonia. Retort water did not appear toxic to dogs, rats, or guinea pigs under the acute test conditions imposed. No research has been done on the long-term chronic effect of retort water on any of these animals. A variety of schemes has been proposed for the treatment of retort water, most of which involve the removal of ammonia. This study was an attempt to find the effects of chronic low-level exposure of fish and wildlife to partially treated oil shale retort water.

Microbiological Degradation of Organic Components in Oil Shale Retort Water: Organic Acids

The losses of benzoic acid and a homologous series of both mono- and dibasic aliphatic acids in oil shale retort water were monitored with time (21 days) in liquid culture (4% retort water, vol/vol) inoculated with soil. The organic acids constituted approximately 12% of the dissolved organic carbon in retort water, which served as the sole source of carbon and energy in these studies. The levels of the acids in solution were reduced by 80 to 90% within 9 days of incubation. From mass balance calculations, the decrease in dissolved organic carbon with time of incubation was equal to the formation of CO(2) and bacterial cell carbon. The decrease in the level of the acid components, either from degradation to CO(2) or incorporation into bacteria, would account for approximately 70% of the loss in dissolved organic carbon within the first 9 days of incubation and would account for approximately 50% of the loss over the entire 21-day incubation period.