What are the environmental impacts of produced water discharge?

Produced water discharge, a byproduct of oil and gas extraction, poses several environmental impacts. Chemical Contamination 🐟☠️ Soil Degradation 🌱 Water Scarcity: 💦📉 Habitat Disruption: 🌍🐾 Greenhouse Gas Emissions: 🏭🌪️ Overall, responsible management and treatment are crucial to mitigate these environmental risks.

Produced water (also called formation water, brine or saltwater) is water from underground formations that is brought to the surface during oil or gas production. It is the largest volume of 568 by-products or waste stream associated with oil and gas exploration and production. The water is discharged in an oily form after its separation from the real oil. During oil and gas exploration other forms of wastewater are produced, these include injected water, little quantity of water that is condensed and traces of some chemicals used among which produced water is the highest generated by-product.

Contaminação da água, alterações na biodiversidade, impactos no solo, risco para a saúde humana, emissões gasosas, impactos nos ecossistemas aquáticos e terrestres, são alguns dos impactos ambientais que o descarte da água produzida fora das especificações pode causar. Para minimizar esses impactos, é essencial implementar práticas de gestão adequadas, tratamento eficiente da água produzida e conformidade rigorosa com regulamentações ambientais. Avanços em tecnologias de tratamento e práticas sustentáveis são importantes para mitigar os efeitos negativos da descarga de água produzida.

TDS, COD, BOD and other unwanted chemical constituents like benzene ...as organic and inorganic ( such as mercury...) chemicals

If produced water is discharged to shallow estuarine and marine waters, some metals and higher molecular weight aromatic and saturated hydrocarbons may accumulate in sediments near the produced water discharge, possibly harming bottom living biological communities. in addition, any user from animals or people will have a negative impact and it will affect his health.

Water disposal is one of the factors that needs to be considered when drilling a well. Many use a water disposal well but they need to be careful with that well because they are injecting fluids in we need to check out the faults in and around the well to avoid induced seismicity. There is added costs to ship that water. Some have proposed to use pipelines instead of trucks to avoid the use of many trucks in an area and to appease stakeholders. Some companies are looking at the use of shallow aquifers to source the water. The water is managed by the regulatory board and during droughts it is restricted. This is why some are going with CO2 instead of water and does not interact with other fluids and better flow back.

It is assumed that 7500 -11,500 tonnes hydrocarbon is released to the environment yearly as a result of formation water discharges worldwide. Considering the large volume of estimated hydrocarbon released worldwide to the environment as a result of formation water discharges, this could alter the natural state of the environment which may lead to different forms of environmental problems. Exploration and production of oil within the Environment will bring changes to their ecosystem.

Operational discharges of produced water and drill cuttings from offshore oil and gas platforms are a continuous source of contaminants to continental shelf ecosystems.

O descarte de água produzida, contêm substâncias químicas tóxicas. Se práticas inadequadas de descarte, dessa água forem adotadas, podem causar efeitos negativos profundos no ecossistema e na biodiversidade, como: declínio de espécies aquáticas, impacto em espécies terrestres, cascata nos níveis tróficos entre outros.

Produced water can be discharged in either water bodies on surface or it can be injected in deep disposal wells which put the water in existing fault systems which act as a sink. Depending on the choice of disposal location, the treatment of water differs. For surface disposal there are stricter requirements for hydrocarbon content, salts, sulphates etc for which the water is treated at group gathering stations and refineries which includes process such as exposing water to sulfate reducing bacteria etc. For subsurface disposal the water quality requirements are less stringent, however, precipitation of salts can be a concern downhole. Hence, water treatment is still a very important step before water disposal to avoid loss of connectivity.

Prácticas como ésta de descargue de aguas de producción a los ecosistemas aparte del daño ambiental generado el cual probablemente no nos percatemos por las condiciones fisicoquímicas del agua es lo que ha generado un problema reputacional en la industria del oil and gas. Mi recomendación es siempre buscar ciclos cerrados en que toda el agua producida sea o bien utilizada en procesos de EOR o en el peor de los casos inyectada en arenas disposal con capacidad de almacenamiento, pero nunca en el medio ambiente.

Produced water, a byproduct of oil and gas extraction, often contains various minerals, including lithium. Lithium, a critical component in batteries for electric vehicles (EVs) and other rechargeable devices, is in growing demand as the world shifts towards sustainable energy solutions. In Alberta, pilot projects are underway to test and optimize the technology for extracting lithium from produced water. These projects are pivotal in demonstrating the feasibility and efficiency of this process. If successful, they could set a precedent for similar operations globally, transforming a waste product into a valuable resource.

In addition, produced water regulatory guidelines should “encourage and incentivize” sustainable water recycling management - that turns produced water into usable and environmentally sustainable water sources. Focusing on negative environmental impacts of produced water will not encourage innovation but rather foster “status quo” sort of policies and practices. As the world usable water resources dwindles, regulatory frameworks should focus on sustainable and environmentally sound practices that convert produced water in usable water for the benefit of all stakeholders. Let’s focus on the opportunities rather than just the problems - that’s what drive innovation and technological growth. Produced water is not all bad news!

Using water disposal wells for water reinjection in oil fields is a practical solution for managing produced water, but it can have negative environmental impacts. The long-term effects of reinjection are not fully understood, and it can lead to unpredictable consequences for the reservoir and the environment. To mitigate these impacts, strict regulations, industry best practices, and robust monitoring systems are essential, particularly in remote areas and developing countries.

Another indirect impact of sediment disposal from produced water treatment is the potential for safety risks. When concentrated contaminants are disposed of in landfills, there is a possibility that these harmful substances can leach out over time or not adequately contained within the landfill-If proper control measures are lacking, there is a risk of unintentional contact with these contaminants by humans, animals, or other organisms. Particularly to individuals who come into direct contact with the sediments. This can occur if the sediments are accidentally released or if there is unauthorized access to the landfill.

I am convinced that the main reason behind environmental problems related to wastewater production is the neglect of this issue during the initial stages of planning for oil and gas field development. It is essential to incorporate sustainable objectives into development plans instead of just focusing on economic goals to consider environmental, economic and social aspects simultaneously. For instance when creating the development plan based on economic objectives solely, the scenarios that involve injecting wastewater into disposal wells or considering essential facilities for water treatment may not be chosen due to the rise in CAPEX but if the plan prioritizes sustainable goals, they will undoubtedly be included in the selected scenario.