district heating plant Plant for heating all houses in a district; it consists of a large, efficient, centralized boiler plant or "waste" steam from a power station. The heat is distributed by means of low-pressure steam or high-temperature water to the consumers
pickling plant Plant where scale is removed from iron and steel usually by means of immersion in a hot hydrochloric or sulphuric acid bath. Wastes include spent pickling liquor, sludges and rinse water
