How can oil, gas, and water be separated more efficiently in processing facilities?

Naturally, Hydrocarbon fluid (water, oil, gas & sediments) are separated by gravity. However, this separation can be enhanced through the following methods: 1. High volume separator: The first stage separator that receives the fluid for initial separation should be big enough to for increased retention time and surface area to liberate more gas from the liquid. 2. Retention time: The more time the fluid stream stays in the separator, the better the separation of the fluid phases. 3. Fluid temperature: To achieve better separation, the fluid temperature should be high enough to avoid formation of emulsion and foaming. This can be achieved using a heat exchanger. 4. Chemical treatment: Chemicals like demulsifier, biocides, anti-foams, etc.

Gravity separation is the most common method to separate a well stream into gaseous and liquid components due to using the naturally occurring specific gravities of the different fluid components without requiring external energy being added into the system. One variable that must be controlled to maximize the efficiency of separation is retention time. Retention time is the time the process fluid is given to settle into its different components (i.e. oil/gas/water).

O separador gravitacional é um equipamento fundamental no mercado do petróleo, pois permite a separação eficiente de líquidos e sólidos. Com sua capacidade de separação por gravidade, esse equipamento é amplamente utilizado em processos industriais para separar substâncias com densidades diferentes. Se você deseja entender como funciona o separador gravitacional e como pode ser útil para sua empresa, confira nosso guia completo sobre o assunto. Neste artigo, vamos explorar tudo o que você precisa saber sobre esse equipamento e como ele pode ajudar a aumentar a eficiência dos seus processos industriais.

gravity separation is the simplest and the quality of separation is also related to the number of separators used. the more separators, the better the quality. There are also other treatments to increase recovery

The most simple onshore gravity separation design is for the inlet production header from field to enter the vertical gas booth, where the gas separated from gross liquid contain oil and water. The gas will leave the gas booth from top outlet, and flow either to gas plant or to be burnt in flare, depending the amount of gas. The water and oil will leave the gas booth from bottom outlet and enter the liquid-liquid separator. The separator in offshore is normally a tank. There, the oil and water will be separated by gravity with some support of slight elevated temperatures (could be by natural or by additional heater) and emulsion breaker. For this type of gravity separation, retention time and temperature are critical success factor.

O processo de centrifugação se utiliza de energia para uma separação mais rápida, sendo um dispositivo mecânico dinâmico para induzir um forte gradiente de pressão e separa o óleo e a água dentro e fora dependendo da densidade, ou seja , a água de alta densidade é empurrada para fora pela força centrífuga e o óleo de baixa densidade é coletado no centro da centrífuga para extrair óleo e água. Partículas de maior densidade ou tamanho maior no sistema tende a centrifugar em um ritmo mais rápido e em algum momento será separado de partículas menos densas ou menores.

Es un excelente metodo de separacion, obviamente requiere de energia adicional que involucra costos, sin embargo es justificada la inversion en sistemas centrifugos.

Centrifugal separation is a process that uses centrifugal force to separate particles or components from a liquid or gas mixture. In a centrifuge, the mixture is rotated at high speeds, creating a centrifugal force that pushes denser particles or components outward. The separated components are then collected based on their density and mass. This method is commonly used in various industries, including oil and gas, pharmaceuticals, and wastewater treatment, for tasks such as separating solids from liquids, purifying liquids, and clarifying suspensions.

Special membranes selectively allow certain molecules (e.g., water) to pass, while others (e.g., oil) are retained. Choosing the right membrane material and configuration is key.

The best say to separate mixed components is using de sg factor, membranes could improve the efficency of the separators. This principle is used in well testing operations.

Recordemos que las membranas es un metodo de separacion casi a nivel molecular, el petroleo su factor de ensuciamiento es alto, a etapas iniciales de procesamiento, es complicado y muy costoso el mantenimiento y reemplazo

A process that utilizes magnetic properties to separate materials.It involves the use of magnets or magnetic materials to attract &separate magnetic substances from non-magnetic ones.This technique is commonly employed in various industries, including mining, recycling, and the processing of minerals. Magnetic separators, such as magnetic drums, plates,and pulleys,are used to achieve this separation by creating a magnetic field.The magnetic force attracts or repels materials, depending on their magnetic susceptibility,leading to the separation of different components in a mixture. Magnetic separation is effective for removing ferrous contaminants from materials and is widely utilized for tasks like ore beneficiation and recycling processes.

Irradiação de microondas prevê o aquecimento seletivo dos componentes no óleo residual e induz a elevação determinada de temperatura, resultando na redução da viscosidade e modificação das propriedades da superfície, acarretando no aumento da coalescência das gotículas e melhora separação do óleo residual. 

We try to inject water vapor to raise the oil to the top, and there is a steam separator that increases the lifting pressure .

The future efficiency for the oil and gas industry is going to be data driven through the use of SCADA (supervisory control and data acquisition) and it is already being implemented. SCADA (1) acquires process data that is transmitted to a remote UI where data trends can be monitored and analyzed in real time (i.e. a high-pressure alarm) and (2) allows the user to directly interact with various sensors, valves, pumps, motors, etc. This capability of SCADA improves efficiency by reducing downtimes and using acquired data for smarter decision making.

Advanced Separation Technologies: Continued development of innovative separation technologies such as membrane separation, electrostatic coalescence, and nanotechnology-based solutions to enhance the efficiency of separating oil, water, and gas mixtures. Automation and AI Integration: Increased use of automation, machine learning, and AI-driven systems for real-time monitoring, predictive maintenance, and optimization of separation processes, leading to improved efficiency and reduced downtime.

Subsurface separation is a great idea because it not only helps increase the life of an oil well but save the operator the hassle/expense of handling water at the surface. The only challenge is to find a subsurface which allows to dump separated water in a zone that doesn’t communicate vertically with the source rock. Vertical permeability tests must be conducted to rule out that possibility. If this is achieved then this may be the best way to separate unwanted water at the source. The other challenge is to design/find a slim and efficient downhole separator which could withstand extreme downhole conditions. Effective realtime downhole monitoring and communication is a must to the success of the project.

Many years ago when I was an active PT, Shell was championing the so-called DHOWS system. This was essentially a downhole separation and disposal system where produced water was separated and disposed downhole. Hence achieving all the benefits that my esteemed colleague Khalid Gilani is talking about. I think that was a centrifugal separation system. Shell was going to run a couple of pilots, one of them was supposed to be in Oman. Does anybody know what came of that? There was also a person stewarding this technology in Rijswijk. Unfortunately, I can’t remember his name. Given the quantum of water being produced, this technology is worth pursuing. However, I think candidate wells with the required disposal horizon may be a challenge.

Our Smart Wells (SW) team did a study on combining DHOWS with SW, as the matching and control of production and injection flows (& pressures) was tricky. What killed the idea in the end was the economics, as usual. Spending more Capex on individual wells and completions to do ‘distributed’ water mngmt versus treating the water cost-effectively at surface and reinfecting in dedicated disposal wells. Have you considered dual inj/prod completions with zonal control?

We invariably look to solve many if not most phase separation problems, especially oil/water, by treating the symptoms instead of the disease. My advice is before you start heating and treating, look upstream and examine the process configuration.

I modeled and installed one in Venezuela with ESP of 750HP with injection sand below the producing zone. DHOWS does not remove water 100%. It cannot as the separation is not effective at lower (<40%) water cut. However, the significant water is removed with production fluid containing 80-90% water and separated water is directed into injection zone with the pressure of ESP. Casing size should be 7" or higher. New well can be designed with this object in mind. The injection zone can be either below or above, for which completion is designed to direct water into injection strata. Houston