Vattenkvalitet

This document specifies the basic design and construction requirements for wastewater treatment plants for over 50 PT.
NOTE 1 Requirements for structures which are not specific for wastewater treatment plants are not within the scope of this document. Other ENs can apply.
NOTE 2 Equipment which is not solely used in wastewater treatment plants is subject to the applicable product standards. However, specific requirements for such equipment when used in wastewater treatment plants are included in this part.

This Part 7 of the EN 12255 series specifies design principles and performance requirements for secondary and tertiary treatment of wastewater in biological fixed-film reactors at wastewater treatment plants for more than 50 PT.
Its primary application is for wastewater treatment plants for the treatment of domestic and municipal wastewater. It can also be applied for biodegradable industrial wastewater.
Biological fixed film reactors include rotating biological contactors (RBC), biological trickling reactors (BTR), moving bed biological reactors (MBBR), submerged medium reactors (SMR) and submerged media filters (SMF). Membrane Bioreactors (MBR) and anaerobic processes are not within the scope.
Some of the systems using fixed film bacteria are enhanced activated sludge systems (hybrid systems). For such systems, EN 12255-6 also applies.
This document provides fundamental information about typical systems and does not provide information about all available fixed film systems.

This document specifies a method for the determination of total organic carbon (TOC), dissolved organic carbon (DOC), total bound nitrogen (TNb) and dissolved bound nitrogen (DNb) in the form of free ammonia, ammonium, nitrite, nitrate and organic compounds capable of conversion to nitrogen oxides under the conditions described. The procedure is carried out by automated analysis.
NOTE Generally the method can be applied for the determination of total carbon (TC) and total inorganic carbon (TIC), see Annex A.
The method is applicable to water samples (e.g. drinking water, raw water, ground water, surface water, sea water, waste water, leachates).
The method allows a determination of TOC and DOC ≥ 1 mg/l and TNb and DNb ≥ 1 mg/l. The upper working range is restricted by instrument-dependent conditions (e.g. injection volume). Higher concentrations can be determined after appropriate dilution of the sample. The determination of
concentrations <1 mg/l is dependent on instrument conditions applying appropriate calibration.
For samples containing volatile organic compounds (e.g. industrial waste water), the application of the difference method could be considered, see Annex A.
Cyanide, cyanate and particles of elemental carbon (soot), when present in the sample, can be determined together with the organic carbon.
Dissolved nitrogen gas (N2) is not determined.

This part of ISO 5667 describes the basic methods for sampling suspended microplastics in water (domestic water, freshwater, seawater, treated wastewater, and untreated wastewater), for their subsequent characterization. Suspended particles could also include synthetic or semi-synthetic polymeric materials (such as rubber). This standard does not cover chemical analysis, biological (ecotoxicological) methods or physical methods, nor the pre-treatment or digestion methods intrinsic to such analyses.
This document covers general methodologies for grab sampling, sampling using a set of successive filters of different pore sizes (cascade filtration), for water samples with low, medium and high content of suspended solids; and net sampling, using, for example, manta, plankton or neuston nets.