Ключевые слова: circle, city drainage, civilization, clean, cleaner, conservation, dirty, ecology, ecosystem, effluent, environment, environmental, factory, hamburg, heavy, industrial, industry, large containers, modern, overflow, plant, pollution, population, port, process, purification, purified, purity, recycle, recycling, running water, sedimentation, selfcontained, selfsufficient, separation, settle, sewage, sewer, silos, sludge, station, storage, system, tank, technology, treatment, waste, water, water and sewage station, wind turbin,