Sewage Treatment Plant

Sewage at sea: what sewage is, aerobic versus anaerobic breakdown, MARPOL Annex IV discharge distances, the biological treatment plant, retention and zero-discharge systems, effluent quality, sludge disposal, troubleshooting, maintenance and safety.

10 Topics In this Sub-topic

Sewage Treatment Plant Topics

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01 What Sewage Is — the Definition, the Daily Volumes, and Why It Must Be Treated Define the subject precisely, and establish why a ship spends money and space on treating something that could in principle be pumped over the side. Beginner · 3 min read · 3 sections 02 Aerobic and Anaerobic Breakdown — Why the Colony Dies and How Long Recovery Takes The one distinction on which the whole subject turns. Beginner · 5 min read · 4 sections 03 Where Sewage May Be Discharged — the 4 Mile and 12 Mile Rules Where sewage may be discharged, in what condition, and at what distance from land. Intermediate · 3 min read · 3 sections 04 The Sewage Treatment Plant — Aeration, Settling and Chlorination The machine itself — its compartments, its flow path, its disinfection stage and its settings. Intermediate · 9 min read · 8 sections 05 Retention, Holding and Zero-Discharge Systems — Holding Tanks, Vacuum Toilets and Elsan The arrangements that keep sewage on board rather than treating it. Intermediate · 5 min read · 4 sections 06 Effluent Quality — BOD, Suspended Solids and Coliform Count The three tests that decide whether treated sewage is clean enough to discharge, what each one actually measures, and the numbers that go with them. Intermediate · 5 min read · 4 sections 07 Sludge Disposal — Overboard at Sea, Sullage Tank, or Incinerator What to do with the solids a sewage plant produces. Intermediate · 3 min read · 3 sections 08 Troubleshooting the Sewage Plant — Ten Faults, Cause by Cause A diagnostic index for the sewage plant, the holding tank arrangements and the sludge system. Intermediate · 5 min read · 2 sections 09 Maintenance of the Sewage Plant — Desludging, Aeration and the Daily Checks The routine that keeps a sewage plant alive. Intermediate · 3 min read · 3 sections 10 Safety on the Sewage Plant — Gas Hazards and Enclosed Space Entry The hazards specific to sewage treatment. Intermediate · 5 min read · 6 sections