Review of Phosphorus-Based Polymers for Mineral Scale and Corrosion Control in Oilfield

Abstract

Production chemistry is an important field in the petroleum industry to study the physicochemical changes in the production system and associated impact on production fluid flow from reservoir to topsides facilities. Mineral scale deposition and metal corrosion are among the top three water-related production chemistry threats in the petroleum industry, particularly for offshore deepwater and shale operations. Mineral scale deposition is mainly driven by local supersaturation due to operational condition change and/or mixing of incompatible waters. Corrosion, in contrast, is an electrochemical oxidation-reduction process with local cathodic and anodic reactions taking place on metal surfaces. Both mineral scaling and metal corrosion can lead to severe operational risk and financial loss. The most common engineering solution for oilfield scale and corrosion control is to deploy chemical inhibitors, including scale inhibitors and corrosion inhibitors. In the past few decades, various chemical inhibitors have been prepared and applied for scaling and corrosion control. Phosphorus-based polymers are an important class of chemical inhibitors commonly adopted in oilfield operations. Due to the versatile molecular structures of these chemicals, phosphorus-based polymeric inhibitors have the advantage of a higher calcium tolerance, a higher thermal stability, and a wider pH tolerance range compared with other types of inhibitors. However, there are limited review articles to cover these polymeric chemicals for oilfield scale and corrosion control. To address this gap, this review article systematically reviews the synthesis, laboratory testing, and field applications of various phosphorus-based polymeric inhibitors in the oil and gas industry. Future research directions in terms of optimizing inhibitor design are also discussed. The objective is to keep the readers abreast of the latest development in the synthesis and application of these materials and to bridge chemistry knowledge with oilfield scale and corrosion control practice.

Keywords: corrosion; mineral scale; oilfield; phosphorus; polymers.

Scheme 1

Structure of this review article.

Figure 1

SEM image of stainless-steel tubing in experiments: (a) without the presence of inhibitors, (b) tubing wall with no deposited barite crystal, (c) presence of PPCA, and (d) SPCA [70].

Figure 2

Common structures of phosphorus-containing units in polymers.

Figure 3

Structures of typical phosphorus-containing polymers.

Figure 4

Phosphorus based vinylic monomer species: (a) VPA and (b) VDPA.

Figure 5

Synthesis and chemical structure of phosphonated polyetheramine derivatives [108].

Figure 6

Functionalization of PCA-COOH with phosphonate groups to PCA-PO₃H₂-COOH [109].

Figure 7

Synthesis of modified polyaspartic acid with aminomethylene phosphonic acid [44].

Figure 8

Schematic structures of methacrylate-based polymeric scale inhibitors with phosphonate and PEG grafts [117].

Figure 9

(a) Generalized structure of a hyperbranched polyethyleneimine, showing primary, secondary, and tertiary amine groups; (b) addition of vinyl monomers to primary and secondary amines. X = phosphonate, sulfonate, or carboxylate [122].

Figure 10

Synthesis approach of HBPs [123].

Figure 11

Potentiodynamic polarization curves recorded for the carbon steel electrode in 3 wt % NaCl solution containing different concentrations of HBP−3 [123].

Figure 12

Synthesis of AA−APES−HPAY [128].

Figure 13

Schematic diagram of AA−APES−HPAY inhibition on calcium scales [128].

Figure 14

An illustration of a scale inhibitor squeeze treatment [137].

Figure 15

Comparison of inhibitor return profiles at different field treatments [152].

Figure 16

Field returns of incumbent inhibitor Product B and the subsequent field trial with Product A on Well E-22 [41].

Figure 17

Field returns of incumbent inhibitor Product B and the subsequent field trial with Product A on Well E-22 [153].