Preposition: from

• tank: Sludge digestion The sludge from the different tanks passes into the digester, a large vessel containing very little air.

Converse of object

• digest: Soil erosion Soil erosion is reduced where digested sludge from farm slurry digester schemes provides a good fertilizer.

• activate: See also activated sludge, a type of green water system where all the nutrients are kept in suspension.

• treat: What happens if treated sludge is dumped in rivers and lakes?

• dry: Sewage sludge: 1million tons of dried sewage sludge is produced every year resulting from 26 million tons of raw sewage sludge.

• remove: All that existed was a fully mobile sludge removed by water alone.

Adjective modifier

• toxic: That is not much greener than a pile of toxic sludge.

• radioactive: Apart from the radioactive sludge it left on the plate.

• liquid: For route 3 the fuel used for bringing liquid sludge or sludge pellets to the farmers is included.

• brown: There were bottles of evil smelling, thick brown sludge, which tasted awful.

• black: Busy at work were brick layers, hedge choppers, a bulldozer and one rather happy-looking bunch knee-high in black sludge.

Modifies a noun

• thickener: Sludge thickener audits carried out at selected treatment works.

• digestion: Such engines are sometimes run partly on the gas ( mostly methane ) from the sludge digestion tanks.

• blanket: We were also the world pioneers of first automatic sludge blanket level detector.

• disposal: The four investigated sludge disposal routes We choose four different disposal routes on which to perform our case study.

• recycling: A new odor control system for the sludge recycling would also be installed during the scheme.

• pellet: For route 3 the fuel used for bringing liquid sludge or sludge pellets to the farmers is included.

Noun used with modifier

• sewage: The dumping of sewage sludge at sea was banned in 2000.

• mill: Whilst the research focuses on one particular composting substrate, paper mill sludge, many of the findings could be of much wider interest.

• waste: They cover stabilization and reduction of waste sludge, and stabilization of residue ground from heaving.