Laboratory and pilot testing of electrocoagulation for removing scaleforming species from industrial process waters

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

This study investigated the performance of electrocoagulation using iron and aluminum electrodes for removing silica, calcium and magnesium from cooling tower blowdown and reverse osmosis reject waters. Experiments were conducted at both the bench and pilot scales to determine the levels of target species removal as a function of the coagulant dose. At the bench scale, aluminum removed the target compounds from both cooling tower blowdown and reverse osmosis reject more efficiently than iron. A 2 mM aluminum dose removed 80% of the silica and 20 to 40% of the calcium and magnesium. The same iron dose removed only 60% of the silica and 10 to 20% of the calcium and magnesium. When operated with iron electrodes, pilot unit performance was comparable to that of the bench unit, which suggests that such systems can be scaled-up on the basis of coagulant dose. However, when operated with aluminum electrodes the pilot unit underperformed the bench unit due to fouling of the electrode surfaces after a few hours of operation. This result was completely unexpected based on the short-term experiments performed using the bench unit.

Original languageEnglish (US)
Pages (from-to)522-526
Number of pages5
JournalInternational Journal of Environmental Science and Technology
Volume6
Issue number4
StatePublished - 2009

Fingerprint

Electrocoagulation
Aluminum
electrodes
aluminum
Electrodes
electrode
Iron
Silicon Dioxide
silica
iron
Magnesium
Osmosis
reverse osmosis
Calcium
magnesium
Coagulants
coagulants
Cooling towers
Water
calcium

Keywords

  • Cooling tower blowdown
  • Electrocoagulation
  • Hardness removal
  • Silica removal
  • Water softening

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Environmental Chemistry
  • Environmental Engineering

Cite this

@article{39d5ed930f614bec95c8deedb1bd26fe,
title = "Laboratory and pilot testing of electrocoagulation for removing scaleforming species from industrial process waters",
abstract = "This study investigated the performance of electrocoagulation using iron and aluminum electrodes for removing silica, calcium and magnesium from cooling tower blowdown and reverse osmosis reject waters. Experiments were conducted at both the bench and pilot scales to determine the levels of target species removal as a function of the coagulant dose. At the bench scale, aluminum removed the target compounds from both cooling tower blowdown and reverse osmosis reject more efficiently than iron. A 2 mM aluminum dose removed 80{\%} of the silica and 20 to 40{\%} of the calcium and magnesium. The same iron dose removed only 60{\%} of the silica and 10 to 20{\%} of the calcium and magnesium. When operated with iron electrodes, pilot unit performance was comparable to that of the bench unit, which suggests that such systems can be scaled-up on the basis of coagulant dose. However, when operated with aluminum electrodes the pilot unit underperformed the bench unit due to fouling of the electrode surfaces after a few hours of operation. This result was completely unexpected based on the short-term experiments performed using the bench unit.",
keywords = "Cooling tower blowdown, Electrocoagulation, Hardness removal, Silica removal, Water softening",
author = "Schulz, {M. C.} and Baygents, {James C} and James Farrell",
year = "2009",
language = "English (US)",
volume = "6",
pages = "522--526",
journal = "International Journal of Environmental Science and Technology",
issn = "1735-1472",
publisher = "CEERS",
number = "4",

}

TY - JOUR

T1 - Laboratory and pilot testing of electrocoagulation for removing scaleforming species from industrial process waters

AU - Schulz, M. C.

AU - Baygents, James C

AU - Farrell, James

PY - 2009

Y1 - 2009

N2 - This study investigated the performance of electrocoagulation using iron and aluminum electrodes for removing silica, calcium and magnesium from cooling tower blowdown and reverse osmosis reject waters. Experiments were conducted at both the bench and pilot scales to determine the levels of target species removal as a function of the coagulant dose. At the bench scale, aluminum removed the target compounds from both cooling tower blowdown and reverse osmosis reject more efficiently than iron. A 2 mM aluminum dose removed 80% of the silica and 20 to 40% of the calcium and magnesium. The same iron dose removed only 60% of the silica and 10 to 20% of the calcium and magnesium. When operated with iron electrodes, pilot unit performance was comparable to that of the bench unit, which suggests that such systems can be scaled-up on the basis of coagulant dose. However, when operated with aluminum electrodes the pilot unit underperformed the bench unit due to fouling of the electrode surfaces after a few hours of operation. This result was completely unexpected based on the short-term experiments performed using the bench unit.

AB - This study investigated the performance of electrocoagulation using iron and aluminum electrodes for removing silica, calcium and magnesium from cooling tower blowdown and reverse osmosis reject waters. Experiments were conducted at both the bench and pilot scales to determine the levels of target species removal as a function of the coagulant dose. At the bench scale, aluminum removed the target compounds from both cooling tower blowdown and reverse osmosis reject more efficiently than iron. A 2 mM aluminum dose removed 80% of the silica and 20 to 40% of the calcium and magnesium. The same iron dose removed only 60% of the silica and 10 to 20% of the calcium and magnesium. When operated with iron electrodes, pilot unit performance was comparable to that of the bench unit, which suggests that such systems can be scaled-up on the basis of coagulant dose. However, when operated with aluminum electrodes the pilot unit underperformed the bench unit due to fouling of the electrode surfaces after a few hours of operation. This result was completely unexpected based on the short-term experiments performed using the bench unit.

KW - Cooling tower blowdown

KW - Electrocoagulation

KW - Hardness removal

KW - Silica removal

KW - Water softening

UR - http://www.scopus.com/inward/record.url?scp=69849114545&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=69849114545&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:69849114545

VL - 6

SP - 522

EP - 526

JO - International Journal of Environmental Science and Technology

JF - International Journal of Environmental Science and Technology

SN - 1735-1472

IS - 4

ER -