Showing papers by "Ecolab published in 2022"

Reverse osmosis: Fundamental causes of membrane deposition and approaches to mitigation

Abstract: Reverse osmosis (RO) has become a common practice for industrial and municipal desalination. Developments in the technology since its commercial beginnings around 1965 have made RO the leading technology for desalination today. Current RO membranes offer higher rejection of solutes and higher permeability of water than membranes did just 10 to 15 years ago. Despite advances in performance over the years, one major challenge still facing the technology is deposition of materials on the membranes. Deposits, including organic compounds, scale, bacteria, and suspended solids, affect system performance via reduced productivity and poor product water quality, ultimately leading to decreased efficiency and increased production costs. Pretreatment, equipment design, and system operations can all impact the nature and degree of deposition, as can the characteristics of the membranes themselves. This chapter discusses RO technology, the nature of deposits, factors that minimize or enhance deposition, and techniques for deposit mitigation.

Quantitative Method to Measure Disinfectant Product Efficacy v2

Abstract: This protocol is used for measuring the inactivation of Pseudomonas aeruginosa by liquid disinfectants. In brief, stainless-steel discs are inoculated with single 10 µL drops of a P. aeruginosa suspension also containing a three-part soil mixture. The three-part soil consists of bovine mucin, bovine serum albumin and yeast extract. The inoculum drops are dried on the discs and then the discs are transferred into flat-bottom vials for testing. Testing involves overlaying each dried inoculum spot with 50 µL of a disinfectant working solution or a negative control solution. A contact time is allowed to elapse and then a disinfectant-neutralizing agent is added. Any material still adsorbed on the carrier is eluted by vigorous washing/mixing of the carrier in the neutralizer. The neutralizer eluate and 10-fold serial dilutions of the eluate are filtered through 0.2-micron membrane filters. The filters are transferred to the surfaces of agar plates and incubated. Colony forming units on the filters are counted and log reductions for the disinfectant treatments are calculated.

Quantitative Method to Measure Disinfectant Product Efficacy v1

Abstract: This protocol is used for measuring the inactivation of Pseudomonas aeruginosa by liquid disinfectants. In brief, stainless-steel discs are inoculated with single 10 µL drops of a P. aeruginosa suspension also containing a three-part soil mixture. The three-part soil consists of bovine mucin, bovine serum albumin and yeast extract. The inoculum drops are dried on the discs and then the discs are transferred into flat-bottom vials for testing. Testing involves overlaying each dried inoculum spot with 50 µL of a disinfectant working solution or a negative control solution. A contact time is allowed to elapse and then a disinfectant-neutralizing agent is added. Any material still adsorbed on the carrier is eluted by vigorous washing/mixing of the carrier in the neutralizer. The neutralizer eluate and 10-fold serial dilutions of the eluate are filtered through 0.2-micron membrane filters. The filters are transferred to the surfaces of agar plates and incubated. Colony forming units on the filters are counted and log reductions for the disinfectant treatments are calculated.