🌐EnglishEnglishBahasa IndonesiaDeutschEspañolFrançaisItalianoNederlandsPolskiPortuguêsSvenskaTiếng ViệtTürkçeРусскийالعربيةفارسی한국어中文日本語EntityQ215624· pop 35· linked from 272 articlesbiochemical oxygen demandoxygen needed to remove organics from waterConnectionssewage treatmentEntitywastewater treatmentEntityCategoriesAnaerobic digestionEnvironmental scienceWater quality indicators