| 摘要 |
<p>PURPOSE:To minimize the error of measured value based on dissolved carbonic acid by acidifying a sample permeated through an ultrafilter and passing gaseous nitrogen or the like to dissipate dissolved carbonic acid and hydrogen sulfide, adding barium chloride or the like to make the residual dissolved carbonic acid insoluble, and thereafter neutralization-titrating with an alkali solution. CONSTITUTION:A specimen is sampled from a methane fermentation tank in a step 101. A phosphoric acid insolubilization reagent is added to this specimen in a step 102. The specimen is treated by an ultrafilter in a step 103. Sampling is performed in a step 104 and sulfuric acid is added to a sample in a step 105 to acidify the sample. Gaseous nitrogen is bubbled in a step 106. Barium chloride or calcium chloride is added to the sample in a step 107. Residual dissolved carbonic acid is precipitated as insoluble barium carbonate and calcium carbonate. The pH of the sample is regulated to 3 by an alkali solution in a step 108. Neutralization-titrating are performed by using N/10 sodium hydroxide in a step 109.</p> |
