FprEN 12255-1

SLOVENSKI STANDARD
oSIST prEN 12255-1:2023
01-september-2023
Čistilne naprave za odpadno vodo - 1. del: Splošna načela gradnje
Wastewater treatment plants - Part 1: General construction principles
Kläranlagen - Teil 1: Allgemeine Baugrundsätze
Stations d’épuration - Partie 1 : Principes généraux de conception et de construction
Ta slovenski standard je istoveten z: prEN 12255-1
ICS:
13.060.30 Odpadna voda Sewage water
oSIST prEN 12255-1:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 12255-1:2023
oSIST prEN 12255-1:2023
DRAFT
EUROPEAN STANDARD
prEN 12255-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2023
ICS 13.060.30 Will supersede EN 12255-1:2002
English Version
Wastewater treatment plants - Part 1: General
construction principles
Stations d'épuration - Partie 1: Principes généraux de Kläranlagen - Teil 1: Allgemeine Baugrundsätze
construction
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 165.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12255-1:2023 E
worldwide for CEN national Members.

oSIST prEN 12255-1:2023
prEN 12255-1:2023 (E)
Contents Page
European foreword . 3
Introduction . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Symbols and abbreviations . 10
5 Requirements . 11
5.1 General requirements . 11
5.2 Design requirements . 12
5.3 Modularity . 14
5.4 Structural requirements . 15
5.5 Requirements for equipment . 17
6 Test methods . 23
6.1 Function and performance . 23
6.2 Tightness testing of concrete structures . 23
6.3 Tightness testing of other structures and equipment . 23
7 Cost Comparison Analysis . 24
Annex A (informative) Design Service Life . 25
Annex B (normative) Structural tolerances . 27
B.1 Circular tank . 27
Annex C (normative) Wall tracks . 28
C.1 Tracks . 28
C.2 Walls . 28
C.3 Wheels . 28
C.4 Freezing conditions . 28
Annex D (normative) Scraper Design . 29
D.1 Physical loads . 29
D.2 Driver control . 29
D.3 Bar and chain scrapers . 29
D.4 Monitoring . 29
D.5 Maintainability . 30
D.6 Design life . 30
Bibliography . 31

oSIST prEN 12255-1:2023
prEN 12255-1:2023 (E)
European foreword
This document (prEN 12255-1:2023) has been prepared by Technical Committee CEN/TC 165 “Waste
water engineering”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12255-1:2002.
The main changes compared to the previous edition are listed below:
a) update of title and scope to incorporate design;
b) comprehensive revision and additions in all sections;
c) adaptation to the current state of the art;
d) updating of the Normative references;
e) editorial revision.
This is the first part prepared by Working Group CEN/TC 165/WG 40 relating to the general
requirements and processes for treatment plants for a total number of inhabitants and population
equivalents (PT) over 50.
The EN 12255 series with the generic title “Wastewater treatment plants” consists of the following
parts:
— Part 1: General design and construction principles
— Part 2 : Storm management systems
— Part 3: Preliminary treatment
— Part 4: Primary treatment
— Part 5: Lagooning processes
— Part 6: Activated sludge process
— Part 7: Biological fixed-film reactors
— Part 8: Sludge treatment and storage
— Part 9: Odour control and ventilation
— Part 10: Safety principles
— Part 11: General data required
— Part 12: Control and automation

Part 2 is under preparation.
oSIST prEN 12255-1:2023
prEN 12255-1:2023 (E)
— Part 13: Chemical treatment — Treatment of wastewater by precipitation/flocculation
— Part 14: Disinfection
— Part 15: Measurement of the oxygen transfer in clean water in aeration tanks of activated sludge
plants
— Part 16: Physical (mechanical) filtration
oSIST prEN 12255-1:2023
prEN 12255-1:2023 (E)
Introduction
Differences in wastewater treatment throughout Europe have led to a variety of systems being
developed. This document gives fundamental information about the systems; this document has not
attempted to specify all available systems. A generic arrangement of wastewater treatment plants is
illustrated in Figure 1.
Key
1 preliminary treatment
2 primary treatment
3 secondary treatment
4 tertiary treatment
5 additional treatment (e.g. disinfection or removal of micropollutants)
6 sludge treatment
7 lagoons (as an alternative)
A raw wastewater
B effluent for re-use (e.g. irrigation)
C discharged effluent
D screenings and grit
E primary sludge
F secondary sludge
G tertiary sludge
H digested sludge
I digester gas
J returned water from dewatering
Figure 1 — Schematic diagram of wastewater treatment plants
The primary application is for wastewater treatment plants designed for the treatment of domestic and
municipal wastewater.
oSIST prEN 12255-1:2023
prEN 12255-1:2023 (E)
NOTE For requirements on pumping installations at wastewater treatment plants see EN 752, Drain and
sewer systems outside buildings and the EN 16932 series, Drain and sewer systems outside buildings — Pumping
systems:
— Part 1: General requirements;
— Part 2: Positive pressure systems;
— Part 3: Vacuum systems.
oSIST prEN 12255-1:2023
prEN 12255-1:2023 (E)
1 Scope
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.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN ISO 9001:2015, Quality management systems - Requirements (ISO 9001:2015)
EN 809, Pumps and pump units for liquids - Common safety requirements
EN 10088-2, Stainless steels - Part 2: Technical delivery conditions for sheet/plate and strip of corrosion
resisting steels for general purposes
EN 12255-9, Wastewater treatment plants - Part 9: Odour control and ventilation
EN 12255-10, Wastewater treatment plants - Part 10: Safety principles
EN 12255-13, Wastewater treatment plants - Part 13: Chemical treatment - Treatment of wastewater by
precipitation/flocculation
EN 16323, Glossary of wastewater engineering terms
EN 60529, Degrees of protection provided by enclosures (IP Code)
EN 60034-1, Rotating electrical machines - Part 1: Rating and performance
EN 16932 (all parts), Drain and sewer systems outside buildings - Pumping systems
EN ISO 14122-2:2016, Safety of machinery - Permanent means of access to machinery - Part 2: Working
platforms and walkways (ISO 14122-2:2016)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 16323 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
oSIST prEN 12255-1:2023
prEN 12255-1:2023 (E)
3.1
structure
construction intended to fulfil a function
[SOURCE: EN 16323:2014, definition 2.1.6.11]
3.2
equipment
any component which is installed in, mounted on, attached to, or operated on structures, in the
performance of their intended function
3.3
unit
any structure including any related equipment which is used as a process stage and which can be
isolated from other parallel, upstream or downstream structures
Note 1 to entry: Examples for a unit are: a grit chamber, a clarifier, an aeration tank, a thickener, a digester.
3.4
assembly
mechanical equipment that can be removed and replaced as a whole
Note 1 to entry: Examples for an assembly are a pump, a compressor, a gas engine, an aerator.
3.5
wastewater treatment plant
f
...