Agenda

A fascinating and diverse range of real oilfield scale control and management topics covering the thorny issues of chemical scale mitigation options for ESPs, to the very latest operator perspective on the 'when/when not to' implement continuous scale inhibitor application downhole in producer wells. Complementing the Session 1 keynote theme, we also present a thoroughly interesting and detailed carbonate scale control and mitigation case study across the life of the Brage oilfield located offshore west Norway.

Challenges in the industry constantly evolve driving the development of new technologies and evaluation methods. Operating conditions are becoming more challenging, e.g. HPHT deep sea, hard to inhibit sulphide scales, high shear systems that exacerbate scale formation. In this session there will be discussions that each field presents unique conditions creating a distinctive set of scaling challenges, the need to understand the scaling risks, develop robust control strategies to ensure the efficiency of any treatments is maximised. Consideration will be given to how advancements are essential to ensure that new chemicals perform effectively, are fit-for-purpose, can successfully be deployed and minimise their environmental impact.

Carbon Capture, Utilization, and Storage (CCUS) is currently a global strategy deemed as critical to limiting global warming to less than 1.5 degrees Celsius, where CO2 captured from heavy industry is transported and injected into suitable geological reservoirs for storage, and/or can be used for enhanced oil recovery. The drive towards net zero in carbon emission has also instigated the development of alternative energy sources to fossil fuels such as geothermal energy. As scale is related to CO2-Water-Rock interactions, it is important to both geothermal and CCUS. This session will include (1) An excellent overview paper highlighting some examples on scale control in geothermal wells with options for treatment and desirable chemical properties and carbonate scale control in CO2 Water Alternating Gas (WAG) injection whilst also demonstrating CO2 storage and enhanced oil recovery (CCUS), as well as the potential for halite deposition and carbonate mineral dissolution and its impact on rock mechanical integrity during CO2 injection into hyper saline aquifers and depleted oil and gas reservoirs will be discussed. (2) A study utilizes two distinctly different techniques to understand the extent to which the presence of a stainless-steel surface impacts the kinetics of scale formation in comparison to only bulk precipitation in low (below 10) SR solutions; and (3) A new method for surface characterization of tubing and pipeline for scale and corrosion and scale characterization.

A Keynote presentation is selected by the conference committee as it is one of the highest rated abstracted submitted in the call for papers. In this keynote paper (SPE-209496) the challenge of zinc sulphide scale control via squeeze treatment at high temperature is evaluated. A thermally stable polyaniline-co-polymer based scale inhibitor (PANI-Co-Polymer SI) has been developed which shows a low minimum inhibitor concentration (<5mg/l) to prevent zinc sulphide scale formation via nucleation inhibition/growth modification and has the potential properties to adsorb/desorb effectively onto a sandstone substrate.

Carbonate scales, especially calcium carbonate, have always been the most common scaling challenge of oil and gas productions. This session explores recent advancements made in understanding the mechanism and kinetic behavior of the formation of calcium carbonate in various field conditions, such as in the presence of a mixture of different fractions of oil in water emulsion, under centrifugal effect, and in the presence of H2S scavengers. This session also addresses findings from lab testing of non-chemical solutions for calcium carbonate scaling inhibition and control.

Field case studies are an excellent source of information on real-life scale issues. In this session, an example from the Oda Field will show how a predicted scale risk (calcium sulphate) did not materialise under production conditions. A case study from the North Sea will show how a non-THPS cleaning chemical package was developed and deployed to mitigate iron sulphide, barium sulphate and biomass deposition during produced water injection. Finally, a study from the Gulf of Guinea will show that on this field, treatment for calcium carbonate, barium sulphate and calcium sulphate scale had to be adapted for individual wells.

Halite and sulphide are less common than carbonate and sulphate scales and are very challenging to treat with high costs for remedial action. In particular, for halite scale where a high frequency of treatment (e.g. daily to weekly) with freshwater interventions is required to remove the scale. This session is designed to capture the most recent developments in laboratory and field technologies and will focus on prediction, new chemistry for dispersion and scale squeeze applications and laboratory testing methods that can replicate the field conditions for halite scales e.g. high temperature and high turbulence.

This session highlights the importance of improving scale treatments, by utilising existing techniques and technologies in an optimal manner to get the best outcome. The session covers both lab and simulation studies. A varied range of techniques are covered including the use of magnets for prevention of scale and the advantages of exploiting synergistic effects from inhibitor blends. A case study is also presented looking at the requirement for an alternative approach for field redevelopment.