Waste water treatment at farms; installations, type of purification, 1993-2009

Within the framework of environmental statistics, CBS collects data on the treatment of urban waste water and on the private treatment of waste water of mainly industrial origin. Urban or public waste water treatment involves the treatment of waste water discharged to the sewer by households and businesses. Private wastewater treatment involves companies and institutions that have their own treatment plant. In the treatment plants, the contaminants are removed from the discharged waste water (influent) by means of mechanical, biological and/or physico-chemical purification techniques. The treated waste water (effluent) is discharged to the surface water. Wastewater treatment results in a residual product, the sewage sludge. In sewage sludge from biological plants, the organic substances can be further decomposed (slib fermentation). This process releases biogas, which can be used for energy generation. The sewage sludge is then stripped of the excess water (dewatering). Then, depending on the quality, the sludge can be reused (for example for compost preparation) or eventually deposited or incinerated. This table contains part of the results of the annual survey of wastewater treatment sludge from companies and institutions: the numbers and design capacity of the private waste water treatment plants, broken down by treatment type. In the table, the data can be divided into the following characteristics: — destination of the treated waste water (effluent); — business class according to the 2008 SBI; — dewatering method of sewage sludge. Data available: 1993-2009 Status of the figures: The figures are final. Changes as of 9 August 2012: The table has been discontinued because the data has now been split into 2 new tables. Data for 2010 and later, on types of installations and disposal of sewage sludge according to the SBI2008 format are included in the StatLine table Waste water treatment at farms; by industry (SBI 2008). Data on types of installations according to installation characteristics are included in the StatLine table Wastewater treatment at plants; installations by type of purification.