Cooling water test

Cooling water test units incorporating heat transfer surfaces... 

After the accident, the cooling water tests revealed 14-percent ethylene glycol (antifreeze) in the system. Tests were conducted with the biocide and the ethylene glycol solution. Investigators learned that after a dormant period of several days, the temperature of the mixture suddenly increased and the solution released bromine gas. Testing showed that at elevated temperatures of about 140° F (60° C), the reaction occurred without the delay. 

Jd] Anon., "Standard Heat Exchanger for Cooling Water Tests, Materials Performance, Augirst 1965. 

NACE Standard TM0286, Cooling Water Test Units Incorporating Heat Transfer Services, NACE International, Houston, TX. 

Cooling Water Test Units Incorporating Heat Transfer Surfaces... 

Specimen Location Steel baffle plate from a test water box containing flowing cooling water... 

A test water box was installed during a 2-week trial to monitor corrosion and fouling in a utility cooling water system. A baffle plate from the test box was removed after the test. Small, hollow incipient tubercles dotted surfaces (Fig. 3.28). Small amounts of carbonate were present atop and around each tubercle. Each tubercle capped a small depression no deeper than 0.005 in. (0.013 cm) (Fig. 3.29). This indicated local average corrosion rates were as high as 130 mihy (3.3 mm/y). 

Substituting one alloy for another may be the only viable solution to a specific corrosion problem. However, caution should be exercised this is especially true in a cooling water environment containing deposits. Concentration cell corrosion is insidious. Corrosion-resistant materials in oxidizing environments such as stainless steels can be severely pitted when surfaces are shielded by deposits. Each deposit is unique, and nature can be perverse. Thus, replacement materials ideally should be tested in the specific service environment before substitution is accepted. 

A leak in another heat exchanger allowed flammable gas to enter a cooling-water return line. The gas was ignited by welding, which was being carried out on the cooling tower. The atmosphere had been tested before work started, five hours earlier (see Section 1.3.2). 

Since corrosion inhibitors are used in a wide range of applications, no universal test method exists. Recognised methods tend to relate to a product or process in which the inhibitor forms a part rather than to the inhibitor per se. Thus, tests exist for inhibited coolants, cooling waters, cutting oils, pickling liquids, etc. 

These tracer and tagged polymer products are very useful for conducting test work such as in the examples given above, but, similar to their application in cooling water, the monitoring system only measures the bulk-water concentration of polymer. This may have little or no relevance to metal surface chemistry and the protective integrity of the magnetite film. 

Cool the contents of the test tube by placing the test tube in the beaker containing cool water. 

Too much flow through valve Both internal pressure valves fail open Operation Excessive chlorine flow to Tower Water Basin - high chlorine level in cooling water - potential for excessive corrosion in cooling water system Rotameter Daily testing of cooling water chemistry Relief valve on Pressure check valve outlet III None... 

The fill material in natural draft cooling towers is frequently asbestos cement. Erosion of this fill material may result in the discharge of asbestos in cooling water blowdown. In a testing program for detection of asbestos fibers in the waters of 18 cooling systems, seven of the 18 sites... 

When the oil reaches a temperature of-4°F(-20°C), remove the test jar from the well. If the oil is not solid at -4°F (-20°C), continue cooling the test sample until it becomes solid and then remove the sample. Place the test jar in a water bath held at a temperature between 116.6°F and 117.5°F (47°C and47.5°C). When the oil sample has reached a temperature of 114.8°F (46°C), remove the sample and perform the standard ASTM D-97 pour point. 

Use Method 1001 of Federal Test Method Standard No 791, except that, due to the high viscosity of the material, cooling water at 40—45° shall be substituted for the ice-water in the condenser... 

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