Title:
PCE Superplasticizers Used as Dispersants in Oil Well Cementing
Author(s):
B. Yu, M. Moumin, and J. Plank
Publication:
Symposium Paper
Volume:
329
Issue:
Appears on pages(s):
55-66
Keywords:
oil well cementing; polycarboxylate; retarder; lignosulfonate; tartaric acid; rheology; compatibility
DOI:
10.14359/51711203
Date:
9/24/2018
Abstract:
Effectiveness of different polycarboxylate superplasticizers in oil well cement and their compatibility with two common retarders (lignosulfonate and tartaric acid) was investigated. As polycarboxylates, copolymers based on MPEG, APEG and IPEG esters/ethers were tested in comparison to a commercial AFS dispersant. Rheological measurements revealed that in cement slurries, all PCE copolymers exhibit superior dispersing performance. The dosage gap to AFS decreased at higher temperature 80 °C (176 °F).
In the presence of the two retarders, performance of the PCE dispersants was reduced, whereby the IPEG-PCE was more robust. Generally, lignosulfonate impaired PCE performance stronger than tartaric acid. A mechanistic investigation revealed that the negative impact of the retarders (tartaric acid) derives from hindrance of PCE adsorption on cement (competitive adsorption).
The results suggest that PCEs generally present powerful dispersants in oil well cement, however, they are more sensitive to retarders than AFS. Although, specifically composed PCE polymers can provide higher robustness.