Search results for "Produced water"
showing 10 items of 10 documents
Performance of a membrane-coupled high-rate algal pond for urban wastewater treatment at demonstration scale
2020
[EN] The objective of this study was to evaluate the performance of an outdoor membrane-coupled high-rate algal pond equipped with industrial-scale membranes for treating urban wastewater. Decoupling biomass retention time (BRT) and hydraulic retention time (HRT) by membrane filtration resulted in improved process efficiencies, with higher biomass productivities and nutrient removal rates when operating at low HRTs. At 6 days of BRT, biomass productivity increased from 30 to 66 and to 95 g.m(-3).d(-1) when operating at HRTs of 6, 4 and 2.5 days, respectively. The corresponding nitrogen removal rates were 4, 8 and 11 g N.m(-3).d(-1) and the phosphorous removal rates were 0.5, 1.3 and 1.6 g P…
Improving Separation of Oil and Water With a Novel Coalescing Centrifugal Pump
2018
Summary A novel centrifugal pump that increases oil-droplet sizes in produced water has been developed. This paper investigates a concept of pumping-pressure optimization, with respect to downstream separation efficiency, for the new pump. The investigation shows that the coalescing centrifugal pump always increased the separation efficiency of a downstream hydrocyclone. Furthermore, it is shown that the pumping pressure can be adjusted to maximize the improvement. Experimental results demonstrate how pumping conditions that minimize the volume fraction of droplets with a diameter smaller than the cut size of the hydrocyclone maximize the separation efficiency. Finally, it is demonstrated h…
Automatic Operation and Control of a Novel Coalescing Centrifugal Pump for Improved Oil/Water Separation
2019
Summary In this paper we present the development and implementation of automatic operation and control for a pump/hydrocyclone produced-water-treatment system to maximize oil/water-separation efficiency. A so-called perturb-and-observe (P&O) algorithm is adapted for a novel centrifugal pump to continuously optimize the point of operation. The novel pump coalesces and increases the size of oil droplets in the produced water, resulting in a unique relationship between the coalescing effect and the point of operation, and allowing for the successful implementation of the P&O algorithm. The algorithm was implemented in two different setups, one measuring the droplet-size distribution be…
Marine Discharges of Offshore Produced Water: the North-East Atlantic Management Strategy
2002
Este capítulo contiene un estudio de Derecho internacional del medio ambiente sobre las normas y estrategias para prevenir y eliminar la contaminación resultante de hidrocarburos y otras substancias causadas por las descargas de agua de producción costa afuera en el mar. Debemos tener en cuenta que no existe ni un solo tratado internacional de ámbito mundial relativo a la contaminación por descargas de hidrocarburos contenidas en las aguas de producción generadas en las instalaciones costa afuera. De hecho, sólo hay una región marina donde existen normas jurídicas y estrategias para hacer frente a este problema de contaminación. La región marina es el Atlántico nordeste y la norma en cuesti…
Desalination of oilfield produced waters via reverse electrodialysis: A techno-economical assessment
2023
Produced waters (PWs) are oilfield waste streams rich in minerals and hydrocarbons whose production rate is largely increased in last decades following the corresponding increase of energy demand. The high salinity level of PWs inhibits the adoption of cheap biological treatments. Also, desalination techniques based on osmotic membranes would require severe pre-treatments. As an alternative, Reverse ElectroDialysis (RED) and Assisted Reverse ElectroDialysis (ARED) are here proposed for the first time to reduce the salinity level of PWs. RED may also guarantee an operation cost reduction thanks to its energy generation. An ad-hoc model for RED and ARED is here developed in order to deal suit…
Improving Separation of Oil and Water Using a Novel Coalescing Centrifugal Pump
2017
Abstract A novel centrifugal pump, which increases oil droplet sizes in produced water, has been developed. This paper investigates a concept of pumping pressure optimization with respect to downstream separation efficiency, for the new pump. The investigation shows that the coalescing centrifugal pump always increases the separation efficiency of a downstream hydrocyclone. Furthermore, it is seen that the pumping pressure can be adjusted to maximize the improvement. Experimental results demonstrate how pumping conditions, which minimize the volume fraction of droplets with a diameter smaller than the cut size of the hydrocyclone, maximize the separation efficiency. Finally, it is exemplifi…
Variable Step Size P&O Algorithms for Coalescing Pump/Deoiling Hydrocyclone Produced Water Treatment System
2020
This paper presents three variable step size P&O algorithms for optimizing the separation efficiency of a coalescing pump/deoiling hydrocyclone produced water treatment system. By continuously adjusting the pumping pressure, and subsequently the coalescing effect, the algorithms are used to minimize the oil concentration downstream the hydrocyclone. Due to the variable step size, the algorithms react rapidly to changes in the upstream produced water characteristics, at the same time as they reduce (or eliminate) steady-state oscillations. Based on both simulation and experimental testing, the study discusses advantages and disadvantages of the algorithms.
An application of Reverse ElectroDialysis: energy production from produced water
2022
Power Production from Produced Waters via Reverse Electrodialysis: A Preliminary Assessment
2022
Wastewaters generated by crude oil extraction processes, called “produced waters” (PWs), are complex solutions that contain organic compounds, mainly hydrocarbons, and often exhibit high salinity. The large amounts of PWs represent a global issue because of their environmental impact. An approach widely used in the oil industry is the reinjection of this wastewater into the extraction wells after a suitable treatment. The high salt concentration of such solutions may be used in salinity gradient technologies to produce green electricity. Among these technologies, reverse electrodialysis (RED) is one of the most promising. In this work, the application of RED for energy generatio…
REVERSE ELECTRODIALYSIS FOR POWER PRODUCTION FROM OILFIELD WASTEWATERS
2022
Produced waters (PWs) are wastewaters generated by crude-oil extraction processes. They can present very different characteristics depending on the field location and production process. Dispersed oil, dissolved organics and solid particles are usually the main components. Moreover, PWs can contain a very high quantity of dissolved salts 1, with a total dissolved solid (TDS) concentration up to 300 g/L. Each barrel of extracted oil requires the simultaneous extraction of 3 barrels of produced water2 on average. PWs are often discharged into the sea, or sent in evaporation ponds thus leading to a dramatic environment impact3. Reinjection in the extraction well is currently the most common an…