IL AWWA Best Paper Award

The Thurston E. Larson Best Paper Award was presented to Robert Spon for his presentation of "Do you Really Have a Free Chlorine Residual?" at the 2005 Annual Meeting of the Illinois Section American Water Works Association held in Springfield,…

Phosphate Treatment FAQs - Part 1

What is phosphate treatment? Phosphates are water treatment chemicals (dry or liquid solutions) used to correct problems resulting from inorganic groundwater contaminants (iron, manganese, calcium, etc.) and also to maintain water quality (inhibit…

Phosphate Treatment FAQs - Part 2

How are phosphate dosages controlled? Since phosphates do not change basic water chemistry, measuring phosphate residuals in the raw and finished water is necessary to monitor the dosage rate. Orthophosphate ion (PO4) is the most common species…

NSF Std. 60 Listed Orthophosphate Chemicals

Approximate % active as PO4 Approximate pH value (1% solution) Name: Phosphoric Acid Formula: H3PO4 % active: 75% (pH 1) Name: Monosodium orthophosphate Formula: NaH2PO4 % active: 79% (pH 4.5) Name: Monopotassium orthophosphate Formula:…

NSF Std. 60 Listed Polyphosphate Chemicals

Approximate % active as PO4 Approximate pH value (1% solution) Name: Sodium acid pyrophosphate Formula: Na2H2P2O7 % active: 86% (pH 4) Name: Tetrasodium pyrophosphate Formula: Na4P2O7 % active: 72% (pH 10.5) Name: Tetrapotassium…

Manganese (Mn) Fraction Analysis

1. Total Mn: Analyze raw water or system water samples for total Manganese. 2. Soluble Mn: Analyze water samples using the PAN Method, but delete the use of the ascorbic acid reagent (reducing agent) in the Hach Step #6 to identify the initial…

Iron (Fe) Fraction Analysis

1. Total Fe: Analyze raw or finished water sample using Ferrover #8008 for total Iron. 2. Soluble Fe: Analyze raw or finished water sample using the 1,10 Phenanthroline Method #8146 to determine soluble iron. Soluble unbound (ferrous) iron…

Phantom Free Chlorine Residuals

A growing number of water systems have naturally occurring ammonia (NH3-N) and organic contaminants (TOC) in their water supplies. These contaminants react with chlorine treatment to form combined chlorine residuals (chloramines, chlororganics),…