Apparatus for the chemical conditioning of sludges

A process for the conditioning of sludge comprising:

• a. feeding sludge to the lower part of a first vertically arranged cylindrical vessel having a sealed bottom and a sealed top;
• b. treating the sludge by the addition of a flocculant;
• c. mixing the sludge and flocculant in an intensive manner by conveying the sludge and flocculant in a spiral flow upward through the first vessel to form a sludge mixture;
• d. transferring the sludge mixture to the upper part of a second vertically arranged cylindrical vessel having a sealed bottom and a sealed top;
• e. adjusting the pH of the sludge mixture by the addition of a fluid neutralizing agent;
• f. mixing the sludge mixture and neutralizing agent in an intensive manner by conveying the sludge mixture and neutralizing agent in a spiral flow downward through said second vessel to form a homogeneous conditioned sludge;
• and
• g. recovering the conditioned sludge.

A process for the conditioning of sludge comprising:

• a. feeding sludge to the lower part of a first vertically arranged cylindrical vessel having a sealed bottom and a sealed top;
• b. adjusting the pH of the sludge mixture by the addition of a fluid neutralizing agent;
• c. mixing the sludge and neutralizing agent in an intensive manner by conveying the sludge mixture of neutralizing agent spirally upward through the first vessel to form a sludge mixture;
• d. treating the sludge mixture by the addition of a flocculant;
• e. transferring the sludge mixture to the upper part of a second vertically arranged cylindrical vessel having a sealed bottom and a sealed top;
• f. mixing the sludge mixture and flocculant spirally downward through said second vessel to form a homogeneous conditioned sludge;
• and
• g. recovering the conditioned sludge.

A process for the conditioning of sludge comprising:

• a. feeding sludge to the lower part of a first vertically arranged cylindrical vessel having a sealed bottom and a sealed top;
• b. treating the sludge by the addition of an aqueous solution of iron (III) chloride sulfate containing between 20 and 30% by weight;
• c. mixing the sludge and flocculant in an intensive manner by conveying the sludge and flocculant in a spiral flow upward through the vessel to form a sludge mixture;
• d. transferring the sludge mixture to the upper part of a second vertically arranged cylindrical vessel having a sealed bottom and a sealed top;
• e. adjusting the pH of the sludge mixture to between 10 and 12.5 by the addition of a suspension hydrated lime;
• f. mixing the sludge mixture and suspension of hydrated lime in an intensive manner by conveying the sludge mixture and suspension of hydrated lime in a spiral flow downward through said second vessel to form a homogenous conditioned sludge;
• and
• g. recovering the conditioned sludge.