Alkalinity a. Test Method: Measure pH according to method indicated in ASTM F 710. b. Acceptable Results: pH between 8 and 10.
Alkalinity. Alkalinity in waters was determined by titrating a 25 mL aliquot of the sample with 0.02 N H2SO4 using a Corning combination electrode and a Corning model 135 pH meter. The end point was pH
Alkalinity. Alkalinity concentrations over the sample period suggest that the Moyie River is moderately sensitive to acid inputs, although concentrations seem to have increased post site reactivation (Figure 3). The median alkalinity value increased from 16.5 mg L-1 (1990-1995) to
Alkalinity. Inorganic carbon species in the BLM include carbonate (CO2−), bicarbonate (HCO−), 3 3 and carbonic acid (H2CO3). The sum of these species is referred to as dissolved inorganic carbon (DIC). Bicarbonate is usually the most important DIC species in natural waters, because it is the dominant species between pH 6.35 and 10.33. Inorganic carbon is a critical input to the BLM because many metals form carbonate complexes. The one exception is Ag, which does not form carbonate complexes; DIC is not a critical input to BLM applications for Ag. Unfortunately, measurements of DIC are not often taken in natural water samples, but DIC can be estimated from alkalinity and pH measurements, as in Equation 4-1. DIC Alk . [H ] K1 1 K2 [H ] Equation 4-1 where:
Alkalinity. Alkalinity can cause damage to certain types of flooring and in some cases may cause adhesion failure in some manufacturer’s adhesives. Check Alkalinity limitations found on the technical data sheet before using STAUF’s adhesives, sealers, primers, leveling compounds, or other products. Exotic Species: Bamboo, Wenge, Cherry, Teak, and other exotic species react differently to moisture and humidity. Consult your local STAUF Distributor representative for details prior to installation of any exotic species, or call STAUF Technical Services. Note: Bamboo is a grass, not wood. STAUF warrants that our adhesives specified for Bamboo flooring will permanently bond it to the sub floor when properly installed. However, Bamboo Flooring which cups, bows, end-lifts, shrinks, expands, or otherwise reacts adversely to moisture following installation with any STAUF product is not covered under STAUF's Warranty. Such reaction is a clear indication of an unstable flooring product or moisture condition and is not caused by the application of STAUF products. Moisture Related Warranties: Many STAUF products carry a moisture related warranty and have specific limitations. If conditions are found to be in excess of the product’s limitations, STAUF will not be responsible for product failure or floor performance in such cases. Please refer to each product’s Technical Data Sheet for parameters. All pre-installation tests from the flooring manufacturer, the National Wood Flooring Association (NWFA), and STAUF USA, LLC, and any other applicable installation guidelines must be strictly followed. Note: Failure to utilize moisture tests and the recording of those proper tests prior to installation or use of any STAUF product will void the warranty.
Alkalinity. Once filtered, total alkalinity was performed using a Hach® digital titration test kit (Model AL- DT) to an end-point (pH=4.5) measured with the Xxxxx® multi-parameter probe previously described (Method 10244, 2011). Briefly, 25mL of sample was measured in a volumetric flask (class A) and transferred to a 100mL class A volumetric flask (VF). To wash out any residual sample, two 25mL portions of distilled water were added to the original 25mL volumetric flask (VF), swirled momentarily and then added to the 100mL VF containing sample. Next the 100mL VF was filled to the 100mL xxxx with distilled water; inverted ten times to mix and then added to a 250mL plastic beaker. Using the calibrated pH probe, while stirring, 0.16N sulfuric acid was added drop-wise with a digital titrator (Item #1690001) until sample pH reached 4.5 units at which the digit reading was recorded. Once end-point was reached, total alkalinity as meq/L of CaCO3 was calculated according to the method guidelines. Immediately after alkalinity measurements filtered samples were refrigerated at ~8°C to slow down any reaction kinetics.
Alkalinity. Total alkalinity was measured in effluent samples that had display pH values greater than 4.5 during field measurement. As a consequence, influent AMD and the effluent of reactor 1 (LS) had never reached pH values over 4.5 and thus were documented as each displaying no titratable alkalinity (Figure 12 & 13). 4500 Total Alkalinity Alkalinity (mg/L as CaCO3) 4000 3500 3000 2500 2000 1500 1000 500 Influent Reactor 1 (LS) Reactor 2 (10:90) Reactor 3 (30:70) Reactor 4 (50:50) Reactor 5 (70:30) Reactor 6 (90:10) 0 Sampling Date Figure 12: Total alkalinity (mg/L as CaCO3) measured in the effluent of each reactor (R1-R6) during the course of this experiment. 1000 Alkalinity (mg/L as CaCO3) 900 800 700 600 500 400 300 200 100 0 Total Alkalinity Influent Reactor 1 (LS) Reactor 2 (10:90) Reactor 3 (30:70) Reactor 4 (50:50) Reactor 5 (70:30) Reactor 6 (90:10) Sampling Date Figure 13: Expended view of total alkalinity (mg/L as CaCO3) measured in the effluent of each reactor (R1-R6) during the course of this experiment. Notice that influent AMD and reactor 1 (limestone only) did not record pH > 4.5 and thus contained no titratable alkalinity. Within the biologic reactors, a large increase in alkalinity was most pronounced in R3, R4 and R5 with reactors 3 and 4 reaching alkalinity as high as 4,200 mg/L as CaCO3 during the second week. Continued measurements identified that high levels of alkalinity could not be maintained and all reactors had decreased to values below 500 mg/L as CaCO3 by November 2012. From November 2012 to May 2013, notable differences between alkalinity was expressed between each bioreactor as ligneous (R2, R3), 50/50 (R4) and herbaceous (R5, R6) had average alkalinity values of 97, 132 and 275 mg/L as CaCO3, respectively. Furthermore, total alkalinity was only measured in R5 (70:30) after May 2013.
