| 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.; Wastes can be added to hot mix asphalt (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.; The effectiveness of using offshore drilling waste was determined with some regular tests such as, Marshall stability and the flow test, density void analysis, permeability of HMA concrete, leachability and stripping or moisture damage. Some advanced tests such as, indirect tensile resilient modulus, fatigue and creep and permanent deformation tests were also performed to obtain the performance of waste mixed HMA concrete. All the critical tests showed good results except stripping for which alternatives such as, the use of anti-stripping agents have been suggested. 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 new technique offers significant promises for OSDW recycling. (Abstract shortened by UMI.)... |
