Laserfiche WebLink
<br /> <br />WHOLE EFFLUENT TOXICITY <br />TEST MODIFICATION PROCEDURE <br />Bi-Carbonate Dissolved Solids P.lteration <br />pH adjustment with H:SO, to erpel Carbon Dioxide (COz) <br />Reagents: <br />5.0, 1.0, 0.5, and 0.02 Normal ACS grade H,SO, and 1.0, 0.5, <br />and 0.0^< t:cr,~ral ACS grade L:aOY.. <br />Procedure: <br />Blank preparation: <br />1. Reconstituted laboratory dilution water is used as the test <br />blank. The initial pH (pH i) is recorded. <br />2. 500 milliliters is adjusted to pH 3 by adding 1.0 Normal <br />HzSOa dropwise. The volume of acid solution added is recorded. <br />3 . As the pH approaches 3 , 0. 5 N and 0.02 N H,SOa is added <br />dropwise so not to overshoot pH 3. Acid solution volumes <br />added are recorded. <br />4. After 1 hour, if the pH is greater than ± 0.2 units of pH <br />3, acid or base is added as appropriate to pH 3. The pH 3 <br />sample is then adjusted to pH i with 1.0 N, 0.5 N, and 0.02 N <br />NaOH added dropwise. The volumes of acid or base added are <br />recorded. <br />5. After 2 hours, the pH of the adjusted sample is checked. <br />If the pH is greater than + 0.2 units of pH i, acid or base is <br />added as appropriate to pH i. This is repeated every half <br />hour until the sample equilibrates. <br />Effluent preparation: <br />1. The initial pH (pH i) is recorded. <br />2. 500 milliliters is adjusted to pH 3 by adding 1.0 Normal <br />HZSO, dropwise. The volume of acid solution added is recorded. <br />3. As the pH approaches 3, 0.5 N and 0.02 N H,SOa is added <br />dropwise so not to overshoot pH 3. Acid solutions volumes <br />added are recorded. <br />4. After 1 hour, if the pH is greater than = 0.2 units of pH <br />3, acid or base is added as appropriate to pH 3. The pH 3 <br />sample is then adjusted to pH i with 1.0 N, 0.5 N, and 0.02 N <br />NaOH added dropwise. The volumes of NaOH added are recorded. <br />5. After 2 hours, the pH of the adjusted sample is checY.ed. <br />If the pH is greater than + 0.2 units of pH i, acid or base is <br />added as appropriate to pH i. This is repeated every half <br />hour until the sample equilibrates. <br />-1- <br />COMMERCIAL TESTING & ENGINEERING <br />'n~na~ Copv Watermarketl <br />or Four Pro,en.on <br />