Sewage Sludge

Name:
Sewage Sludge
Detailed information:
A mixture of organic materials resulting from purification of municipal waste. There are two types: (1) Imhoff sludge: a low-grade sludge containing 2–3% ammonia and about 1% phosphoric acid.See Imhoff Tank.(2) Activated sludge: a high-grade sludge containing 5.0–7.5% ammonia and 2.5–4.0% phosphoric acid.

Derivation:

(1) By running sewage through settling tanks without access of air. The sludge or solid matter is decomposed by anaerobic bacteria. Lagooning may be used effectively following activated sludge treatment. (2) By running sewage through settling tanks and pumping air (or oxygen) through porous plates at the bottom of the tanks; 20% of the current “make” is also added. The waste acts as nutrient for aerobic bacteria, that consume the polluting organic matter. The resulting solids are filtered and dried.

Use:

Fertilizer base.