Abstract
Carbonate-sulphide mixed scale problems have been reported when water is produced from carbonate reservoirs. The mechanistic understanding of CaCO3 co-precipitation with sulphide scales is not extensively studied to date. This paper presents a detailed study of the interactions of lead/zinc sulphides co-precipitating with calcite. The relationship between bulk precipitation and deposition on a metal surface of the mixed carbonate-sulphide scales is examined when the mixed scales begin to nucleate, agglomerate and grow. CaCO3 crystals appears to transform from a stable rhombohedral crystal to a orthormbic variant crystal and then to an extreme acicular crystal in the presence of sulphide scales. CaCO3 crystals description differed between lead sulphide and zinc sulphide scales when co-precipitated togther.
These transformations are more significant in the presence of PPCA, the CaCO3 crystals formed on the metal surface are highly distorted, while those formed in bulk solution solution are hardly changed. The nature of these mixed crystals may indicate that mixed sulphide scales tends to prefer forming in solution rather than adhere to metal surface in protected zones. This indicate that the mixed sulphide scale may be controlled in one area but unprotected in other regions. Effective mitigation measures for mixed carbonate-sulphide scales may involve both metal surface and bulk solution scale control.
These transformations are more significant in the presence of PPCA, the CaCO3 crystals formed on the metal surface are highly distorted, while those formed in bulk solution solution are hardly changed. The nature of these mixed crystals may indicate that mixed sulphide scales tends to prefer forming in solution rather than adhere to metal surface in protected zones. This indicate that the mixed sulphide scale may be controlled in one area but unprotected in other regions. Effective mitigation measures for mixed carbonate-sulphide scales may involve both metal surface and bulk solution scale control.
Original language | English |
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Title of host publication | SPE International Symposium and Exhibition on Formation Damage Control 2014 |
Place of Publication | Richardson, Texas |
Publisher | Society of Petroleum Engineers |
Pages | 757-781 |
Number of pages | 25 |
ISBN (Electronic) | 9781613993033 |
ISBN (Print) | 9781632660824 |
DOIs | |
Publication status | Published - 2014 |
Event | SPE International Symposium and Exhibition on Formation Damage Control 2014 - Lafayette, United States Duration: 26 Feb 2014 → 28 Feb 2014 |
Conference
Conference | SPE International Symposium and Exhibition on Formation Damage Control 2014 |
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Country/Territory | United States |
City | Lafayette |
Period | 26/02/14 → 28/02/14 |