| 摘要 |
PURPOSE:To facilitate dehydration treatment, by setting water content at an inflection point where proportional relation which is formed between a drying time and an evaporation amount up to a certain point when a definite amount of sludge is heated at a predetermined temp., disappears as the limit value of the water content of a dehydrated cake due to a filter press. CONSTITUTION:A definite amount of sludge is taken in a container and succeedingly heated at a constant temp. of 50-100 deg.C while the change in the wt. thereof is measured at a constant time interval, for example, at an interval of 15-30min. As shown in the figure, an evaporated moisture amount X is in proportional relation to a time up to a certain time A which shows an inflection point where proportional relation disappears hereafter and, when a time is further elapsed, the evaporation amount of moisture is reduced and, at last, an evaporation curve becomes horizontal. Water content X at the inflection point A is approximate to the limited value of moisture removed by a filter press. By this method, a preparatory test by a real machine or an experimental small filter is despensed with and the water content of a dehydrated cake due to the filter press is determined and sludge treatment is made easy. |
