Measuring deposit forming capacity with microbalance

A technology of micro balance and measuring pool, which is applied in the direction of using material absorption and weighing, testing food, measuring devices, etc., which can solve impractical problems and achieve the effect of sensitive application

Inactive Publication Date: 2005-07-27
NALCO CO
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method is limited to calcium carbonate precipitation and is impractical for use in certain circumstances where the test fluid flows from the reservoir through the impingement fluidic unit in constant circulation

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Measuring deposit forming capacity with microbalance
  • Measuring deposit forming capacity with microbalance
  • Measuring deposit forming capacity with microbalance

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0090] Screening of Calcium Oxalate Precipitation Inhibitors in Simulated Solutions

[0091] A solution of 1 mM (128 ppm) calcium oxalate for testing was prepared as follows. Sodium oxalate (0.268g) and calcium chloride dihydrate (0.294g) were each dissolved in 35ml of 0.1N hydrochloric acid. The solutions were diluted with deionized water to about 100ml, and mixed under vigorous stirring. After dilution, the solution was diluted to 2L with deionized water. If necessary, 0.1N hydrochloric acid was added to adjust the pH value of the solution to 2.6. This solution was used as a control. A possible inhibitor is added to the remainder of the solution. The results are given in Table 2.

[0092] test solution

Embodiment 2

[0094] Mass accumulation of calcium oxalate precipitates as a function of applied current density on titanium-coated QCMs

[0095] Table 3 presents the results. A 1 mM (128 ppm) calcium oxalate test solution with a bulk pH of 2.4 was used in the test. After calcium oxalate was deposited on the surface of the QCM, a reverse current was applied (applied current density + 2.0mA / cm 2 ). It was observed that the mass of calcium oxalate decreased rapidly due to its dissolution without damage to the QCM.

[0096] table 3

[0097] Applied current density

Embodiment 3

[0099] Screening of Calcium Oxalate Precipitation Inhibitors under Acidic Conditions in Simulated Fluids

[0100] A 4 mM (128 ppm) supersaturated solution of calcium oxalate with a bulk pH of 1.8 was used in the test. Inhibitors (concentration 20 ppm on a dry weight basis) were added prior to equimolar mixing of the calcium chloride and calcium oxalate solutions. Continuous probing with a surface pH probe estimated that an applied 22mA / cm 2 The electric current raises the pH to 2.5-3.0. The results are given in Table 4.

[0101] test solution

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A method for measuring the deposit forming propensity of a continuously flowing fluid having a bulk pH of about 1 to about 12 comprising measuring the rate at which deposit forms on a quartz crystal microbalance (1) having a top side comprising a working electrode (16) in contact with the fluid and a bottom side isolated from the fluid, wherein the pH of the fluid proximate to the microbalance is controlled electrochemically at about 1 to about 14 by applying to the working electrode (16) a cathodic current of about -0.001 to about -100 mA / cm<2> or an anodic current of from about 0.001 to about 100 mA / cm<2> and wherein the working electrode (16) is coated with or made of a conductive material on which the rate of hydrogen gas evolution is at least 10 times lower than on a gold cathode in acidic solution.

Description

technical field [0001] The present invention relates to a method and apparatus for measuring the tendency of a fluid to form precipitates and the effectiveness of a precipitate inhibitor. More specifically, the present invention relates to a method of measuring the rate of deposition on the surface of a piezoelectric microbalance immersed in a fluid, wherein said deposition is controlled by electrochemically controlled pH changes in the vicinity of the microbalance. Background of the invention [0002] Precipitation is a persistent problem in a variety of fluid-involving industrial processes, such as pulp bleaching, sugar refining and filtration. Precipitates can remain suspended in the fluid or accumulate on the surface of any material that comes into contact with the fluid. This buildup prevents effective heat transfer, interferes with fluid flow, promotes corrosion processes, and breeds bacteria. [0003] A fundamental detrimental effect associated with said precipitati...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N27/416G01N1/00G01N5/02G01N27/00G01N27/26G01N27/27G01N27/42G01N29/02G01N29/22G01N29/30G01N33/02G01N33/18
CPCG01N33/1853G01N2291/0256G01N27/42G01N17/008G01N29/022G01N29/30G01N2291/0426G01N29/222
Inventor S·M·舍甫琴柯D·L·库兹内彻夫P·Y·达基腊拉
Owner NALCO CO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap