| 摘要 |
An alkaline earth metal compound is added to the sludge in a sufficient quantity to bind the proteins. Generally, the pH is then already greater than 6.5, otherwise it is adjusted to above 6.5 by addition of an alkali metal hydroxide or an alkaline earth metal hydroxide. The sludge is then heated to a temperature which is above the coagulation point of the proteins present, a water phase being released which is separated off. This water phase contains the precipitant and can be reused for precipitating proteins. The advantage of the process described here is that not only is a concentration or thickening of the precipitated protein-containing sludge achieved, but also the precipitant is recovered for further use. |
