Nahcolite is a naturally occurring sodium bicarbonate mineral found in subsurface formations. American Soda LLP conducted field tests to prove that nahcolite can be deep mined using low-cost conventional solution mining method. The process involved the injection of hot, high pressure water down wells into a nahcolite deposit about 2,600 feet below the surface where the mineral is dissolved and brought to the surface for recovery. The monitoring and optimization of recovery efficiency based on scores of upstream process parameters, such as water injection rate, required the monitoring of produced liquid density. This was done initially with a mass meter located immediately downstream of the well head. Co-production of small amounts of gas, mainly methane and carbon dioxide, entrained in the liquid phase prevented the accurate measurement of the solution density using a Coriolis meter technology. Premier Instruments provided a remedy with a gas liquid cylindrical cyclone (GLCC © 1 ) separator properly sized and engineered for the process requirements. A gas control valve with liquid level feedback was used to eliminate the entrained gas in the liquid phase. This strategy proved to be functional which allowed American Soda to proceed with the field development. Today, 26 production wells employ the GLCC separator at each production well.

Despite continuous research and development on drilling fluids and waste minimization during the last 40 years, offshore drilling waste (OSDW) remains a significant environmental concern for the petroleum industry. OSDW contains three types of contaminants namely, heavy metals from drilling fluid, oil from oil based mud or petroleum contamination and naturally occurring radioactive substances from exposed formations. In this study a promising and permanent solution based on recycling of OSDW as road construction materials has been investigated. It has been revealed previously that five to ten percent of some waste materials such as recycled asphalt pavement, tire rubber, glass, roofing shingles, polythene etc. can be added to hot mix asphalt (HMA) concrete without sacrificing its strength and performance. These wastes can be added to the HMA by either replacing the mineral filler or proportionately reducing the amount of virgin material in the original mix. In this laboratory test study, different percentages of OSDW were added as aggregate replacement and the properties of resulting blends were evaluated. Three beneficial actions, namely, incineration, dilution and solidification took place. At the end, the effectiveness of using OSDW was determined with the Marshall stability and flow, permeability of HMA concrete, leachability and resilient modulus. It has been found that for the drilling waste used in this research the percentage that can be used in HMA concrete without sacrificing its properties is as high as 20%. Even though the percentage of waste that can be used as aggregate replacement varies with waste types and properties, the proposed technique offers significant promises for OSDW recycling.

This investigation is directly relevant to various applications associated with the safety aspects of underbalanced drilling operations where de-oxygenated air may be co-injected with oil-based drilling fluid. However, de-oxygenated air often still contains up to 5% oxygen by volume. This residual oxygen can react with oil during the drilling process, thereby forming potentially hazardous oxidized hydrocarbons and compromising the safety of drilling operations. This article examines the conditions and processes by which oxidation reactions occur and may be helpful in reducing risk in drilling operations. This project characterizes the oxidation behaviour of several oils and a typical oil-based drilling fluid at atmospheric and elevated pressures using thermogravimetry (TG) and pressurized differential scanning calorimetry (PDSC). Tests performed on mineral matrix (core) from the oil reservoirs showed no reactivity in both inert and oxidizing atmospheres. In an inert atmosphere, tests on all hydrocarbon samples showed only vapourization, no reactivity. In an oxidizing environment, the tests on hydrocarbons showed several oxidation regions. The presence of core had no effect on the behaviour of the hydrocarbons tested in an inert atmosphere but accelerated the higher temperature oxidation reactions of the oil samples. The oil-based drilling fluid exhibited the opposite effect — the presence of core material retarded the oxidation reactions. This is perhaps due to the presence of an oxygen scavenger reacting with oxygen containing clays present in the mineral matrix. In all tests performed on mixtures of hydrocarbon and core in oxidizing atmospheres, elevated pressures resulted in acceleration of the lower and higher temperature reaction regions.

Consideration of a global viewpoint in modern impact analyses suggests that we should favor the efficient use of available infrastructure over the wasteful development of new infrastructure when comparable volumes of oil and gas production are concerned. This global benefit of efficient development is overlooked in traditional environmental impact analyses that typically focus on local concerns within a narrow geographic range. This traditional approach, which is common in more affluent developed countries, may actually contribute to increased global impacts by establishing stringent regulatory regimes discouraging development that would allow the efficient long-term use of that infrastructure. This disregard for global efficiencies favors development in underdeveloped countries where economic development goals may overshadow local concerns for environmental protection. This paper is based upon the results of a study of onshore industrial infrastructure capacity in Central California sponsored by the U.S. Minerals Management Service. This study evaluates the oil and gas production potential of offshore leases that could be accommodated by existing infrastructure and a balanced program of facility replacement. Though these oil and gas resources were originally identified over ten years ago, local environmental policies have delayed their development. An example of oil and gas production activities in other parts of the world that provide energy supplies equivalent to this unrealized potential is described along with an overview of selected environmental characteristics. This paper concludes that environmental review procedures addressing oil and gas development should include consideration of global implications of locally restrictive approval policies.