Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

ISO draws attention to the possibility that the implementation of this document may involve the use of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s) which may be required to implement this document. However, implementers are cautioned that this may not represent the latest information, which may be obtained from the patent database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.

Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.

This document was prepared by the European Committee for Standardization (CEN) (as CEN/TR 14742:2006) and was adopted, without modifications other than those given below, by Technical Committee ISO/TC 275, Sludge recovery, recycling, treatment and disposal.

The second sentence was added in the Scope;
informative references were moved from Clause 2 to the Bibliography;
the term “sludge” was added in Clause 3;
in Clause 5, the reference to Annex B was replaced by reference to Figure B.1.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

Introduction

The laboratory assessment of flocculated sludge dewaterability is sensitive to the operating procedure adopted for the conditioning step. No generalized ranking of products in order of effectiveness can be given since the ranking changes with the sludge type, dosage of conditioning agent (inorganic coagulant, polymer), degree of shearing and dewatering device.

1 Scope

This method gives a standardized procedure for the conditioning operation when selecting a conditioning product at laboratory scale and also for the production of flocculated thickened sludge for subsequent dewatering tests.

This document provides a method for laboratory chemical conditioning of sludge.

The method applies to sludges and suspensions from:

storm water handling;
urban wastewater collecting systems;
urban wastewater treatment plants;
industrial wastewater that has been treated similarly to urban wastewater;
water supply plants.

This document is applicable to all sludge that can have similar environmental or health impacts, or both, with exclusion of hazardous sludge from industry and dredged sludge.

2 Normative references

3 Terms and definitions

4 Principle

5 Apparatus

5.1

5.2

5.3

5.4

5.5

5.6

5.7

6 Procedure

6.1

6.2

6.3

6.4

6.5

6.6

6.7

6.8

7 Test report

8 Precision

Bibliography