The novel approach for the improvement of fluid loss control in water-based mud using nanosilica as filler for pectin

Fluid loss is the leakage of the liquid phase of drilling fluid, slurry or treatment fluid containing solid particles into the formation matrix. The resulting buildup of solid material or filter cake may be undesirable, as may the penetration of filtrate through the formation. Nanosilica and pectin are potential fluid loss additives used in water-based mud to reduce fluid loss and invasion of solid particles into the formation. The objective of this research work was to introduce nanosilica and pectin as fluid loss control agents in basic water-based mud at ambient condition and 250°F. The experimental results were then compared with commercial fluid loss control agent (i.e., HydroPac R) in basic water-based mud (WBM). The laboratory experiments were conducted using different concentrations ranging from 0.50 – 1.50 lb/bbl (wt. %) of nanosilica, pectin, and HydroPac R. The laboratory works were conducted as per the API Recommended Practice 13 B-1 (2009). The experimental results revealed that pectin gave a comparable fluid loss control performance as compared to HydroPac R (i.e., pectin was able to yield 7 cc of filtrate volume compared with HydroPac R which yield 6.6 cc of filtrate volume at the end of 30 minutes under low pressure of 100 psi and at ambient temperature) while nanosilica, an amorphous silica powder, produced the worst performance (i.e., 10 cc of filtrate volume at the end of 30 minutes). The experiment work was then repeated using the mixture of pectin and nanosilica as filler. The mixture yields a better reading than mud samples containing only pectin by reducing further fluid loss by 5%. The research work revealed that pectin with nanosilica as filler has the potential to be used as a fluid loss control agent in water-based mud as it produces a comparable performance with HydroPac R

International nosocomial infection control consortium (INICC) report, data summary of 36 countries, for 2004-2009

The results of a surveillance study conducted by the International Nosocomial Infection Control Consortium (INICC) from January 2004 through December 2009 in 422 intensive care units (ICUs) of 36 countries in Latin America, Asia, Africa, and Europe are reported. During the 6-year study period, using Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN; formerly the National Nosocomial Infection Surveillance system [NNIS]) definitions for device-associated health care-associated infections, we gathered prospective data from 313,008 patients hospitalized in the consortium's ICUs for an aggregate of 2,194,897 ICU bed-days. Despite the fact that the use of devices in the developing countries' ICUs was remarkably similar to that reported in US ICUs in the CDC's NHSN, rates of device-associated nosocomial infection were significantly higher in the ICUs of the INICC hospitals; the pooled rate of central line-associated bloodstream infection in the INICC ICUs of 6.8 per 1,000 central line-days was more than 3-fold higher than the 2.0 per 1,000 central line-days reported in comparable US ICUs. The overall rate of ventilator-associated pneumonia also was far higher (15.8 vs 3.3 per 1,000 ventilator-days), as was the rate of catheter-associated urinary tract infection (6.3 vs. 3.3 per 1,000 catheter-days). Notably, the frequencies of resistance of Pseudomonas aeruginosa isolates to imipenem (47.2% vs 23.0%), Klebsiella pneumoniae isolates to ceftazidime (76.3% vs 27.1%), Escherichia coli isolates to ceftazidime (66.7% vs 8.1%), Staphylococcus aureus isolates to methicillin (84.4% vs 56.8%), were also higher in the consortium's ICUs, and the crude unadjusted excess mortalities of device-related infections ranged from 7.3% (for catheter-associated urinary tract infection) to 15.2% (for ventilator-associated pneumonia). Copyright © 2012 by the Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved