Verification of the OOC Mud and Produced Water Discharge Model using lab-scale plume behaviour experiments
Abstract This paper describes comparisons of predictions by the Offshore Operators Committee (OOC) Mud and Produced Water Discharge Model with published data on experimental laboratory-scale observations of plume behavior in flumes, towing tanks, and wind tunnels. The ability of the OOC Model to predict the plume characteristics observed in numerous individual tests of plume behavior covering a wide range of discharge conditions was examined. Data are provided summarizing the predictive ability of the model for all tests. The dimensionless parameters describing the physical characteristics of the plumes were within the range expected for typical Gulf of Mexico produced water and drilling fluid discharges for most of the comparisons. The model was in good to excellent agreement with measurements of plume behavior under most discharge conditions. The model was less accurate for those experimental cases where extreme plume bending occurred. It is believed that turbulence caused by the discharge pipe itself influenced the behavior of these extreme-bending plumes. The predicted density of solids accumulation on the bottom of a towing tank, a lab-scale analogy of the seabed accumulation of drilling solids, was within a factor of two of experimental observations. Excluding the three simulations of extreme bending plumes, the model showed no systematic trend towards either under- or over-estimation of any parameter examined. This suggests that experimental errors or biases may have contributed to observed differences between predictions and observations. The results of the validation testing described in this report increases confidence in the use of OOC Model predictions as an alternative to the difficult and expensive process of performing field measurements for every practical discharge situation.
Development of photolysis enhanced oxidation technologies for the removal of polycyclic aromatic hydrocarbons from offshore produced water
Offshore Produced Water (OPW) represents the largest volume waste stream from offshore oil and gas (OOG) production activities. It poses major environmental and operational challenges to offshore petroleum industries for requiring more efficient and environmental friendly on-site management. This is true particularly under growing regulatory and economic pressure to reduce the impact of waste discharges. Conventional on-site OPW monitoring and treatment is mainly focused on the oil and grease portion for meeting the regulatory standards, while limited efforts have been given to dissolved compounds especially including Polycyclic Aromatic Hydrocarbons (PAHs). PAHs are proved as one of the most significant contributors to the ecological hazard posed by OPW discharges because of their toxicity, persistency, and potential for bioaccumulation even at a trace level. As a result, effective measurement of PAHs in OPW is imperative, and advanced on-site treatment of the effluent is desired to improve the conventional systems. 
This dissertation research focused on the development of new analytical testing methods and photolysis and its enhanced oxidation technologies for treating PAHs in OPW. They are composed of the key tasks including: a) refining of solid-phase extraction (SPE) and liquid-phase microextraction (LPME) pretreatment systems to extract PAHs from OPW; b) enhancement of gas chromotography-mass spectrometry (GC-MS) analytical methods for background and residual PAHs analysis; c) design and fabrication of photochemical oxidation reactors for batch- and bench-scale experiments; d) systematic one-factor-at-a-time (OFAT) analysis of key parameters and factors in the course of direct photolysis and photocatalysis; e) investigation of efficacy, parameters/factors interactions, kinetics and mechanisms of the enhanced hybrid oxidation systems by integrating photolysis and ozonation (O₃) and/or hydrogen peroxide (H₂O₂); and f) development of central composite design (CCD) based response surface modeling (RSM) models for process simulation and optimization. 
The major contribution of this research is the development of compact, efficient, and eco-friendly technologies for on-site OPW testing and treatment. The developed technologies are proved technically sound by lab experiments with high efficiency in detection and removal of PAHs. The research outcomes bring significant environmental, economic and social benefits to industry, government and academia by providing not only effective but also environmentally benign methods for treating OPW generated from OOG production.
A study of buoyant chimney plumes in neutral and stable atmospheres
Abstract Most of the Swedish plume rise observations in 1966 and 1967 were made in neutral or stable conditions. Many of the plumes were found to reach a maximum height at a definite distance downwind after which they levelled off or descended. These heights and distances are plotted nondimensionally using also wind speed, stability and stack gas buoyancy flux. The results agree with a model of “turbulent entrainment” for hot plumes in their first phase (atmospheric turbulence neglected), but the maximum heights observed in slightly stable or windy conditions are smaller than predicted by the model. This is probably due to atmospheric turbulence. Values of the entrainment constant α were 1. (1) evaluated from plume radii on photographs 2. (2) calculated from the plume rises observed. The two averages agree well with each other. Heights and distances to the transition to a second phase were evaluated for all plumes and are found to agree with values expected from the influence of atmospheric turbulence.