Filtration

(oxidizing filters)

Electrodialysis

Pressure Aeration/

Filtration

Oxidation/Precipation/

Filtration

 

Filtration

Greensand

Calcite

(also raise pH to 7.2)

 

 

 

Distillation

Cation Exchange

Reverse Osmosis

 

 

 

 

 

Sand

Cartridges

 

 

 

Coagulation/Filtration

 

Submicron Filtration

*Manganese must be maintained in the soluble manganous (Mn +²) state to avoid fouling and interference with effective reverse osmosis membrane rejection.

 

Activated Carbon (similar to chloroform and

TTHMs, except the treatment life of the activated

carbon may    be one-half or less of that for

chloroform when MTBE will begin to break

through).

For MBTE concentrations greater than 0.1 mg/L,

pre-treat with high air-to-water ratio air stripping

prior to activated carbon filtration.

 

Activated Carbon

Air Stripping

Oxidation followed by retention and filtration

Disinfection for sulfate-reducing bacteria

If H2S is in the hot water only, remove the hot

 water anode rod or replace it with an aluminum anode rod.

 

Note:  Chlorine and hydrogen sulfide are examples of odors that may be reduced by the treatment methods suggested.

 

Neutralizing filter (calcite or calcite plus magnesia

oxide). pH may be increased by alkalies and may

be decreased by acids. Chemical feed of soda ash

 to raise pH or white vinegar to lower pH.

 

Coagulation/Filtration

Submicron Filtration/

Distillation

Reverse Osmosis

Activated Carbon Ion Exchange

(Anion or Cation depending on complexed Ion

Species)

 

Reverse Osmosis

Anion Exchange

 

Reverse Osmosis

 

Distillation

Electrodialysis

 

Distillation

Electrodialysis

Deionization by Ion Exchange (Cation/Anion in

two bed or mixed bed

 

Reverse Osmosis

Cation Exchange

 

Distillation

Electrodialysis

 

(P)* = Proposed Standard

SMCL (mg/L+) = Secondary Maximum Contaminant Level expressed in milligrams per liter (unless otherwise specified).

 

Recognized Treatment Techniques for Meeting the national Secondary Drinking Water regulations with the application

of Point-Of Use Systems

National Secondary Drinking Water Regulations (NSDWRs or secondary standards) are non-enforceable guidelines for contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effect (such as taste, odor or color) in drinking water. EPA recommends secondary

standards to water systems but does not require systems to comply. However, states may choose to adopt them as enforceable standards.

Note: This document addresses the United States Environmental Protection Agency National Primary Drinking Water Regulations in effect at its time of publication. These regulations are continually being reviewed and updated at the federal level. Accordingly, this list of recognized treatment technologies will be reviewed and amended periodically.

 

Copyright © 2011 by Water Quality Association

Cation Exchange

Ultrafiltration

Distillation

 

Reverse Osmosis

Anion Exchange

Deinization

 

Anion Exchange

Activated Carbon

Filtration

Chlorination

 

Electrodialysis

Deionization

 

 

Distillation

Electrodialysis

 

 

Reverse Osmosis

Distillation

Ozonation

 

 

Note: Color units are based on the APHA recommended standard of 1 color unit being equal to 1 mg/L of platinum or chloroplatinate ion.

 

Reverse Osmosis

Cation Exchange

 (20%-90%)

 

Corrosion Control

Distillation

 

 

Activated Alumina

Reverse Osmosis

 

Chlorination

Activated Carbon

Ozonation

 

Electrodialysis

Distillation

 

Reverse Osmosis

Distillation

 

 

National Secondary Drinking Water Regulations - by Nelsen Corporation

Contaminant

SML, MG/I +

Treatment Methods

 

Alkalinity

(measured as calcium carbonate, CaCo)

 

 

 

 

 

Aluminium (AI +³) on case-by-case

 

 

 

Chloride (C1 -¹)

 

 

 

Color

 

No federal limit

Low alkalinity - < 30mg/L

High alkalinity - > 300 mg/L

 

 

 

 

0.05 to 0.2 depending

Reverse Osmosis

circumstances

 

250

 

 

 

15 color units

 

 

 

 

 

Raise alkalinity by feeding 1.5 mg/L of soda as

for each on mg/L of alkalinity needed or calcite

filtration

Lower alkalinity by feeding white vinegar

carbon dioxide; ion exchange dealkalization;

reverse osmosis; distillation or electrodialysis

 

Copper (Cu +²)

 

 

 

Corrosivity

 

 

 

 

 

 

 

 

 

 

 

Fluoride (FI -¹)

 

 

Foaming agents (MBAS)

 

 

 

Hard Water

(measured as calcium carbonate CaCo3)

 

 

 

 

1.0

 

 

 

Non-corrosive

 

 

 

 

 

 

 

 

 

 

 

2.0

 

 

0.5

 

 

 

No federal limit

Soft - < 17.1 to 60

Moderate - 60 to 120

Hard - 120 to 180

Very hard - > 180

 

Calcite or Calcite/Magnesium Oxide (Magnesia)

(5 to 1) Filter to raise pH

Soda Ash Chemical Feed

Polyphosphate Feed

Sodium Silicate Feed

Remove all hydrogen peroxide

Reduce TDS via Reverse Osmosis (partial, split

stream treatment)

Coatings

Insulating Unions with Ground straps around all

insulating breaks in metal pip

 

Remove all calcium and magnesium ions with a cation exchange water softener (general limit is 1710 mg/L total hardness. Above 70 grains per gallon, install two softeners in a series.

 

 

Iron

 

Ferrous Iron (Fe +²)

 

 

 

 

 

 

 

Ferric Iron (Fe +³)

 

 

 

 

Sequestered Iron

Iron Bacteria

 

 

 

Colloidal Iron

 

0.3 (total iron)

 

 

 

 

 

 

 

 

 

0.3 (total iron)

 

 

 

 

Strong oxidation and/or fine (10 micron or < )

filtration

Disinfection and Retention followed by activated

carbon filtration for dechlorination

 

Methyl Tertiary

Butyl Ether (MTBE)

 

 

 

 

 

 

 

Odor

 

No federal limit

 

 

 

 

 

 

 

 

3 threshold odor number

pH

 

 

 

 

Silver (Ag +¹)

 

 

 

 

 

Sulfate (SO4-2)

 

 

Total dissolved solids (TDS)

 

 

 

 

Zinc (Zn+2)

 

 

6.5 - 8.5

 

 

 

 

0.1

 

 

 

 

 

250

 

 

500

 

 

 

 

5

 

 

Contact:

George Hogg

WTC

 

Email:

Copyright © 2015 Water by George

Cell:

 

Postal Address:

PO Box 12699

Lloydminster, AB T9V 0Y4