Induced biochemical interactions in crude oils

In the evolution of oil from sedimentary to reservoir conditions, the hydrogen to carbon ratios decrease while the oxygen, nitrogen, and sulfur to carbon ratios increase. During this process, the oils become heavier and richer in asphaltenes. In terms of chemical composition, the oils become enriched in resins, asphaltenes, and polar compounds containing the heteroatoms and metals. Over the geological periods of time, the chemical and physical changes have been brought about by chemical, biological (biochemical) and physical (temperature and pressure) means as well as by the catalytic effects of the sedimentary matrices, migration, flooding, and other physical processes. Therefore, different types of oils are the end products of a given set of such interactions which were brought about by multiple and simultaneous physicochemical processes involving electron transfer, free radical, and chemical reactions. A biocatalyst introduced into a reaction mixture of the type produced by such reactions will seek available chemical reaction sites and react at the most favorable ones. The rates and the chemical pathways by which the biocatalytic reactions will proceed will depend on the oil type and the biocatalyst(s). Some of the possible reaction pathways that may occur in such complex mixtures are discussed

Biochemical technology for the detoxification of geothermal brines and the recovery of trace metals

Studies conducted at BNL, have shown that a cost-efficient and environmentally acceptable biochemical technology for detoxification of geothermal sludges is most satisfactory, as well as technically achievable. This technology is based on biochemical reactions by which certain extremophilic microorganisms interact with inorganic matrices of geothermal origin. The biochemical treatment of wastes generated by power plants using geothermal energy is a versatile technology adaptable to several applications beyond that of rendering hazardous and/or mixed wastes to non-hazardous by products, which meet regulatory requirements. This technology may be used for solubilization or recovery of a few metals to the isolation of many metals including radionuclides. In the metal recovery mode, an aqueous phase is generated which meets regulatory standards. The resulting concentrate contains valuable trace metals and salts which can be further converted into income generating products which can off-set the initial investment costs associated with the new biotechnology. In this paper, recent developments in this emerging technology will be discussed

Advanced biochemical processes for geothermal brines current developments

A research program at Brookhaven National Laboratory (BNL) which deals with the development and application of processes for the treatment of geothermal brines and sludges has led to the identification and design of cost-efficient and environmentally friendly treatment methodology. Initially the primary goal of the processing was to convert geothermal wastes into disposable materials whose chemical composition would satisfy environmental regulations. An expansion of the R&D effort allowed to identify a combination of biochemical and chemical processes which became a basis for the development of a technology for the treatment of geothermal brines and sludges. The new technology satisfies environmental regulatory requirements and concurrently converts the geothermal brines and sludges into commercially promising products. Because the chemical composition of geothermal wastes depends on the type of the resource and therefore differs, the emerging technology has to be also flexible so that it can be readily modified to suit the needs of a particular type of resource. Recent conceptional designs for the processing of hypersaline and low salinity brines and sludges will be discussed

Recent advances in biochemical technology for the processing of geothermal byproducts

Laboratory studies has shown the biochemical technology for treating brines/sludges generated in geothermal electric powerproduction to be promising, cost-efficient, and environmentally acceptable. For scaled-up field use, the new technology depends on the chemistry of the geothermal resources which influences choice of plant design and operating strategy. Latter has to be adaptable to high/low salinity, temperatures, quantity to be processed, and chemistry of brines and byproducts. These variables are of critical and economic importance in areas such as the Geysers and Salton Sea. The brines/sludges can also be converted into useful products. In a joint effort between industrial collaborators and BNL, several engineered processes for treating secondary and other byproducts from geothermal power production are being tested. In terms of field applications, there are several options. Some of these options are presented and discussed

The significance of chemical markers in bioprocessing of fossil fuels

Biochemical conversion of crude oils is a multi-step process proceeding through a series of biochemical reactions. These reactions can be characterized by a set of chemical markers which are associated with the chemical composition of crude oils. Reactions with heavy crude oils indicate that there is an overall decrease in the concentration and chemical speciation of organic sulfur compounds, and a redistribution of hydrocarbons and organometallic species. The contents of trace metals in the crude oils, such as nickel and vanadium, also decrease. Further, heavy ends of crudes, containing the asphaltenes and the polar nitrogen, sulfur, and oxygen containing fractions, as well as the organometallic compounds and complexes, are biochemically converted to lower molecular weight chemical species. In the studies reported in this paper, microorganisms used to mediate such reactions were thermophilic (>60{degrees}C) and pressure tolerant (up to 2500 psi). These organisms are also capable of biochemical conversion of bituminous and lignite coals in an analogous manner to their action on crude oils and follow similar trends characterized by chemical markers

Geothermal brines and sludges: a new resource

Development of cost efficient biochemical processes for the treatment of geothermal brines and sludges is the main thrust of a major R&D effort at Brookhaven National Laboratory (BNL). This effort has led to the design of an environmentally acceptable, technically and economically feasible new technology which converts geothermal wastes into products with significant commercial potential. These include valuable metals recovery with a metal extraction and recovery efficiency of better then 80% over short periods of time (5-25 hours). The new technology also yields valuable salts, such as potassium chloride and generates high quality pigment free silica. The basic technology is versatile and can, with slight modifications, be used in the treatment of hypersaline as well as low salinity brines and sludges. Concurrently traces of toxic metals, including radium are removed to levels which are within regulatory limits. The current status of the new biochemical technology will be discussed in this paper

Advanced biochemical processes for geothermal brines: Current developments

A research program at Brookhaven National Laboratory (BNL) which deals with the development and application of processes for the treatment of geothermal brines and sludges has led to the identification and design of cost-efficient and environmentally friendly treatment methodology. Initially the primary goal of the processing was to convert geothermal wastes into disposable materials whose chemical composition would satisfy environmental regulations. An expansion of the r and D effort identified a combination of biochemical and chemical processes which became the basis for the development of a technology for the treatment of geothermal brines and sludges. The new technology satisfies environmental regulatory requirements and concurrently converts the geothermal brines and sludges into commercially promising products. Because the chemical composition of geothermal wastes depends on the type of the resource, the emerging technology has to be flexible so that it can be readily modified to suit the needs of a particular type of resource. Recent conceptional designs for the processing of hypersaline and low salinity brines and sludges will be discussed

Environmental significance of biocatalytic conversion of low grade oils

Studies dealing with the interactions between extremophilic microorganisms and crude oils have led to the identification of biocatalysts which through multiple biochemical reactions catalyze desulfurization, denitrogenation, and demetalation reactions in oils. Concurrently, the oils are also converted to lighter oils. These complex biochemical reactions have served as models in the development of the crude oil bioconversion technology to be applied prior to the treatment of oils by conventional chemical processes. In practical terms, this means that the efficiency of the existing technology is being enhanced. For example, the recently introduced additional regulation for the emission of nitrogen oxides in some states restricts further the kinds of oils that may be used in burners. The biocatalysts being developed in this laboratory selectively interact with nitrogen compounds, i.e. basic and neutral types present in the oil and, hence, affect the fuel NOx production. This, in turn, has a cost-efficient influence on the processed oils and their consumption. In this paper, these cost-efficient and beneficial effects will be discussed in terms of produced oils, the lowering of sulfur and nitrogen contents, and the effect on products, as well as the longevity of catalysts due to the removal of heteroatoms and metal containing compounds found in crudes

Induced biochemical interactions in immature and biodegraded heavy crude oils

Studies in which selective chemical markers have been used to explore the mechanisms by which biocatalysts interact with heavy crude oils have shown that the biochemical reactions follow distinct trends. The term biocatalyst refers to a group of extremophilic microorganisms which, under the experimental conditions used, interact with heavy crude oils to (1) cause a redistribution of hydrocarbons, (2) cause chemical changes in oil fractions containing sulfur compounds and lower the sulfur content, (3) decrease organic nitrogen content, and (4) decrease the concentration of trace metals. Current data indicate that the overall effect is due to simultaneous reactions yielding products with relatively higher concentration of saturates and lower concentrations of aromatics and resins. The compositional changes depend on the microbial species and the chemistry of the crudes. Economic analysis of a potential technology based on the available data indicate that such a technology, used in a pre-refinery mode, may be cost efficient and promising. In the present paper, the background of oil biocatalysis and some recent results will be discussed