CEN/TS 15364:2006

Characterization of waste - Leaching behaviour tests - Acid and base neutralization capacity test

This Technical Specification is applicable to determine the acid and/or base neutralization capacity of a material. The property is expressed in mol/kg. This Technical Specification is a parameter specific test as specified in EN 12920. The application of this test method alone is not sufficient for the determination of the detailed leaching behaviour of a waste under specified conditions. The property allows assessing the final pH of mixed waste as well as consequences of external influences (carbonation, oxidation) on the pH of a waste.
NOTE   This generally requires the application of several test methods, behavioral modeling and model validation as specified in EN 12920.

Charakterisierung von Abfällen - Untersuchung des Auslaugungsverhaltens - Prüfung der Säure- und Base-Neutralisationskapazität

Diese Technische Spezifikation gilt für die Bestimmung der Säure- und/oder Base-Neutralisationskapazität eines Stoffes. Diese Eigenschaft wird in mol/kg ausgedrückt. Diese Technische Spezifikation ist eine parameterspezifische Prüfung, wie in EN 12920 festgelegt. Die Anwendung dieses Prüfverfahrens allein ist für die Bestimmung des genauen Auslaugungsverhaltens eines Abfalls unter festgelegten Bedingungen nicht ausreichend. Die Eigenschaft ermöglicht die Bewertung sowohl des endgültigen pH-Wertes von Abfallgemischen als auch der Auswirkungen äußerer Einflüsse (Karbonatisierung, Oxidation) auf den pH-Wert eines Abfalls.
ANMERKUNG   Dies erfordert im Allgemeinen die Anwendung mehrerer Prüfverfahren, die Verhaltensmodellierung und Validierung von Modellen, wie in EN 12920 festgelegt.

Caractérisation des déchets - Essais de comportement à la lixiviation - Essai de capacité de neutralisation acide et basique

La présente Spécification technique s’applique à la détermination de la capacité de neutralisation acide et/ou basique d’un matériau. Cette propriété est exprimée en mol/kg. La présente Spécification technique est un essai paramétrique, tel que spécifié dans l’EN 12920. Cette méthode d’essai n’est pas suffisante, à elle seule, pour déterminer en détail le comportement à la lixiviation d’un déchet dans des conditions spécifiées. La propriété permet d’évaluer le pH final des déchets mélangés ainsi que les conséquences des influences extérieures (carbonatation, oxydation) sur le pH d’un déchet.
NOTE   En règle générale, ceci nécessite l’application de plusieurs méthodes d’essai, une modélisation du comportement, ainsi qu’une validation des modèles, comme spécifié dans l’EN 12920.

Karakterizacija odpadkov – Izluževalni preskusi – Preskus kislinske in alkalne kapacitete

General Information

• Status: Published
• Publication Date: 11-Apr-2006
• ICS: 13.030.01 - Wastes in general
• ICS: 47.020.30 - Piping systems
• Technical Committee: CEN/TC 444 - Environmental characterization
• Drafting Committee: CEN/TC 444/WG 1 - Leaching tests
• Current Stage: 9093 - Decision to confirm - Review Enquiry
• Start Date: 16-Jun-2009
• Completion Date: 16-Jun-2009
• Ref Project: SIST-TS CEN/TS 15364:2006 - Characterization of waste - Leaching behaviour tests - Acid and base neutralization capacity test

Overview

CEN/TS 15364:2006 - "Characterization of waste - Leaching behaviour tests - Acid and base neutralization capacity test" - is a European Technical Specification for measuring the acid neutralization capacity (ANC) and base neutralization capacity (BNC) of waste and related materials. The method expresses neutralization capacity in mol/kg (mol H+/kg dry matter) and is intended as a parameter-specific test within the framework of waste characterization (EN 12920). It helps predict the final pH of mixed wastes and evaluate effects of external processes (e.g., carbonation, oxidation) on pH, but is not sufficient alone to define full leaching behaviour.

Key topics & technical requirements

• Test principle: Establish equilibrium pH values by contacting pre-weighed test portions with leachants containing pre-selected amounts of acid or base. Determine net mol H+/kg as a function of pH.
• pH range & resolution: At least 8 final pH values, covering minimum pH 4 to pH 12, including the natural pH; max step between consecutive pH values ≤ 1.5 pH units.
• L/S ratio: Fixed liquid-to-solid (L/S) = 10 L/kg (±0.2 L/kg) for the test run.
• Contact time: Total test duration 48 hours, divided into acid/base addition (0–4 h), equilibration (4–44 h) and verification (44–48 h); equilibrium defined by pH stability within 0.3 pH units during final 4 h.
• Sample preparation: Test material prepared so 95% by mass < 1 mm; crushing and sieving rules apply; dry residue determined at 105 °C to calculate dry matter.
• Test portions: Typical dried mass sizes 15 g, 30 g or 60 g (±10%); pH measured with a meter accurate to ±0.05 pH units.
• Reporting: ANC and BNC reported as positive (acid) and negative (base) mol/kg values; include test conditions, L/S, dry matter, pH curve and equilibrium verification.

Applications and users

• Assessing likely final pH of mixed wastes and buffering potential against acidification or alkalinization.
• Screening for impacts of carbonation, oxidation or other environmental changes on waste pH.
• Input for behavioural modelling and risk assessment of landfill leachates, combined with other leaching tests and model validation (EN 12920).
• Typical users: environmental testing laboratories, waste characterization specialists, landfill designers, regulatory authorities, researchers, and practitioners evaluating reuse of soils, sediments or construction materials.

Related standards

• EN 12920 - framework for parameter-specific tests and behavioural modelling
• prEN 14346 - determination of dry residue (water content)
• EN 14899 - sampling of waste materials (sampling plan)
• prEN 14997 - influence of pH on leaching by continuous pH control

Keywords: CEN/TS 15364:2006, acid and base neutralization capacity, ANC, BNC, leaching behaviour test, waste characterization, L/S ratio, pH range, equilibrium.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2006
Karakterizacija odpadkov – Izluževalni preskusi – Preskus kislinske in alkalne
kapacitete
Characterization of waste - Leaching behaviour tests - Acid and base neutralization
capacity test
Charakterisierung von Abfällen - Untersuchung des Auslaugungsverhaltens - Prüfung
der Säure- und Base-Neutralisationskapazität
Caractérisation des déchets - Essais de comportement a la lixiviation - Essai de capacité
de neutralisation acide et basique
Ta slovenski standard je istoveten z: CEN/TS 15364:2006
ICS:
13.030.01 Odpadki na splošno Wastes in general
47.020.30 Sistemi cevi Piping systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL SPECIFICATION
CEN/TS 15364
SPÉCIFICATION TECHNIQUE
TECHNISCHE SPEZIFIKATION
April 2006
ICS 47.020.30
English Version
Characterization of waste - Leaching behaviour tests - Acid and
base neutralization capacity test
Caractérisation des déchets - Essais de comportement à la Charakterisierung von Abfällen - Untersuchung des
lixiviation - Essai de capacité de neutralisation des acides Auslaugungsverhaltens - Prüfung der Säure- und Base-
et des bases Neutralisierungskapazität
This Technical Specification (CEN/TS) was approved by CEN on 2 February 2006 for provisional application.
The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the CEN/TS can be converted into a European Standard.
CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available
promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS)
until the final decision about the possible conversion of the CEN/TS into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN/TS 15364:2006: E
worldwide for CEN national Members.

Contents
page
Foreword .3
Introduction.4
1 Scope.5
2 Normative references.5
3 Terms and definitions .5
4 Symbols and abbreviations .6
5 Principle .6
6 Reagents and laboratory devices.7
7 Sampling .7
8 Test procedure.9
9 Performance characteristics.12
10 Test report.12
Annex A (informative)  Example of a data sheet .13
Annex B (informative)  Preliminary determination of the acid/base consumption.14
Annex C (informative)  Examples of acid and base neutralisation capacities for waste, soil,
sediment and construction materials and use of the data .18
Annex D (informative)  Examples of steps in the full evaluation of ANC and BNC for waste
materials.20
Bibliography.21

Foreword
This Technical Specification (CEN/TS 15364:2006) has been prepared by Technical Committee CEN/TC 292
“Characterisation of waste”, the secretariat of which is held by NEN.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to announce this CEN Technical Specification: Austria, Belgium, Cyprus, Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden,
Switzerland and United Kingdom.
Introduction
This Technical Specification has been developed primarily to support the requirements for leaching behaviour
testing within EU and EFTA countries. Tests to characterize the behaviour of waste materials can generally be
divided into three categories. The relationship between these tests are summarized below:
1. “Basic characterization“ tests are used to obtain information on the short and long term leaching behaviour and
characteristic properties of waste materials. Liquid/solid (L/S) ratios, leachant composition, factors controlling
leachability such as pH, redox potential, complexing capacity, ageing of waste and physical parameters are
addressed in these tests.
2. “Compliance“ tests are used to determine whether the waste complies with a specific behaviour or with specific
reference values. The tests focus on key variables and leaching behavior previously identified by basic
characterization tests.
3. “On-site verification“ tests are used as a rapid check to confirm that the waste is the same as that one which has
been subjected to the compliance test(s). On-site verification tests are not necessarily leaching tests.
The test procedure described in this Technical Specification belongs to category (1): basic characterization tests.
NOTE When sufficient information is available for a material type or class, a single measurement to a relevant final pH may
suffice. In that case, the procedure would qualify as a category 2 method.
In the test, which is described in this Technical Specification, equilibrium condition is established at different pH
values as a result of the reaction between pre-selected amounts of acid or base and test portions of the waste
material. Size reduction is performed to accelerate reaching of equilibrium condition.
This test is different from the method to assess the influence of pH on leaching with initial acid/base addition, in that
the chemical analysis of inorganic constituents in eluates produced is not carried out.
The neutralization capacity can also be derived from a test addressing the influence of pH on leaching by
continuous pH control as described in prEN 14997. The test addressing the influence of pH on leaching by
continuous pH control can be particularly suitable in the case of measurement of pH influence on leaching at a pH
where a small pH change leads to strong change in release.
1 Scope
This Technical Specification is applicable to determine the acid and/or base neutralization capacity of a material.
The property is expressed in mol/kg. This Technical Specification is a parameter specific test as specified in EN
12920. The application of this test method alone is not sufficient for the determination of the detailed leaching
behaviour of a waste under specified conditions. The property allows assessing the final pH of mixed waste as well
as consequences of external influences (carbonation, oxidation) on the pH of a waste.
NOTE This generally requires the application of several test methods, behavioral modeling and model validation as specified
in EN 12920.
2 Normative references
The following referenced documents are indispensable for the application of this Technical Specification. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced document
(including any amendments) applies.
prEN 14346:2004, Characterization of waste – Calculation of dry matter by determination of dry residue and water
content
EN 14899, Characterization of waste - Sampling of waste materials - Framework for the preparation and application
of a Sampling Plan
3 Terms and definitions
For the purposes of this Technical Specification, the following terms and definitions apply.
3.1
dry residue
w
dr
remaining mass fraction of a sample after a drying process at 105 °C
[prEN 14346:2004]
3.2
eluate
solution obtained by a laboratory leaching test
3.3
equilibrium condition
condition achieved when the pH deviation during a checking period at the last 4 h of the test is below 0,3 pH unit
3.4
laboratory sample
sample or subsample(s) sent to or received by the laboratory
[IUPAC, 1997]
3.5
liquid to solid-ratio
L/S
ratio between the amount of liquid (L) and of solid (S) in the test
NOTE L/S is expressed in l/kg dry matter.
3.6
leachant
liquid to be mixed with the test portion in the leaching procedure
3.7
suspension
mixture of leachant and test portion
3.8
test portion
amount or volume of the test sample taken for analysis, usually of known weight or volume
[IUPAC, 1997]
3.9
test sample
sample, prepared from the laboratory sample, from which test portions are removed for testing or analysis
[IUPAC, 1997]
4 Symbols and abbreviations
ANC acid neutralization capacity
BNC base neutralization capacity
DM dry matter
L/S liquid to solid ratio
M dried mass of the test portion
d
m mass after drying
d
M un-dried mass of the test portion
w
m mass before drying
r
t time at the start of the leaching test
V volume of acid or base used in leachant
A/B
V volume of de-mineralized water used in leachant
demin
V volume of added leachant
L
w dry residue of the waste
dr
5 Principle
Separate test portions are prepared at a fixed L/S ratio with leachants containing pre-selected amounts of acid or
base in order to reach stationary pH values at the end of the extraction period. Each leachant is added in three
steps in the beginning of the test. At least 8 final pH-values are required, covering at the minimum the range
pH 4 to pH 12 (both included i.e. the lowest value ≤4 and the highest value ≥12). From the amounts of acid or base
needed to cover the pH range the acid or base neutralization capacity (ANC, BNC) of the test material is
determined. The equilibrium condition as defined in 8.1 is verified at the end of the extraction period.
For each final pH value the quantity of acid that is added is expressed in mol H+/kg DM and the quantity of base that is
+ +
added is expressed as negative mol H /kg DM (-mol H /kg DM). The net mol/kg (+ for acid - for base) is presented as a
function of pH.
NOTE  The pH range covered by the test may be restricted to a pH range relevant for the specific material and the
considered problem (see 8.2).
6 Reagents and laboratory devices
6.1 Reagents
6.1.1
Distilled water, demineralized water or water of equivalent purity with a conductivity < 0,1 mS/m
6.1.2
Nitric acid (pro analysis), 0,1 mol/l to 5 mol/l
6.1.3
Nitric acid (pro analysis), 1 mol/l
6.1.4
Sodium hydroxide, NaOH, 0,1 mol/l to 5 mol/l
6.2 Laboratory devices
6.2.1
Agitation device: end-over-end tumbler (5 r/min to 10 r/min) or roller table rotating at about 10 r/min
6.2.2
Analytical balance (accurate to 0,1 g)
6.2.3
Bottles (250 ml for the test portions of 15 g of dry mass, 500 ml for test portions of 30 g dry mass and 1 l for test
portions of 60 g dry mass) made of polypropylene (PP) or polyethylene (PE).
6.2.4
Crushing equipment, e.g. a jaw crusher
NOTE Crushing is prescribed to avoid unnecessary grinding to very fine particle sizes, such as takes place in a rotary swing
mill, ball mill or similar device.
6.2.5
pH meter with a measurement accuracy of at least ± 0,05 pH units
NOTE At high pH values the use of specific electrodes is recommended.
6.2.6
Sample splitters for a minimum test portion size equivalent of 15 g of dry mass
6.2.7
Sieving equipment with sieve of 1 mm nominal screen sizes
7 Sampling
7.1 Laboratory sample
The laboratory sample shall consist of a mass equivalent of at least 1 kg of dry mass.
Perform sampling in accordance with EN 14899 or a standard derived from EN 14899 in order to obtain a
representative laboratory sample.
7.2 Preparation of test sample
The tests shall be made on material with a grain size of 95 % less than 1 mm. In order to ensure that the test
sample consists in 95 % mass of particles less than 1 mm in diameter, it shall be sieved, using the sieving
equipment (see 6.2.7), to separate the oversized particles. If oversized material exceeds 5 % (mass) the entire
oversized fraction shall be crushed. Any non-crushable material (e.g. metallic parts such as nuts, bolts, scrap) shall
be separated from the oversized fraction and the weight and nature of the non-crushable material shall be
recorded. Crushed and uncrushed material shall be mixed to constitute the test sample.
Moist material that is not possible to sieve needs to be dried prior to sieving and/or crushing. The drying
temperature shall not exceed 40 °C.
NOTE 1 There is no obligation to sieve if it is obvious that the material will fully pass the sieve on 1 mm.
NOTE 2 The crushed material can change upon storage due to ageing of fresh surfaces. It is therefore preferable to test the
material as soon as possible after crushing.
NOTE 3 It is recommended that materials with a high natural pH be crushed under nitrogen in order to avoid contact with air
leading to carbonation.
7.3 Determination of dry residue
The whole test sample, complying with the size criteria in 7.2 shall not be further dried. The dry residue (w ) of the
dr
test sample shall be determined on a separate test portion.
The dry residue shall be determined at 105 °C ± 5 °C according to prEN 14346. The dry residue is calculated as
follows:
m
d
w = 100 × (1)
dr
m
r
where
w is the dry residue of the waste expressed as a percentage (%);
dr
m is the mass after drying expressed in grams (g);
d
m is the mass before drying expressed in grams (g).
r
7.4 Test portion
Prepare at least 8 test portions by the use of a sample splitter (6.2.6) or by coning and quartering. Based on
sample heterogeneity and eluate volume requirement for analysis, test portion size shall be either M = 15 g, 30 g
d
or 60 g (with a tolerance of ± 10 %).
Calculate the undried mass of the test portion M to be used for the test as follows:
w
M
d
M = ×100 (2)
w
w
dr
where
M is the dried mass of the test portion expressed in grams (g);
d
M is the undried mass of the test portion expressed in grams (g);
w
w is the dry residue of the waste expressed as percentage (%).
dr
8 Test procedure
8.1 Contact time
The leaching procedure consists of three defined stages:
• Period A (acid/base addition) from t up t +4 h for acid/base addition in three steps;
0 0
• Period B (equilibration period) from t up to t +44 h equilibration period;
0+4 h 0
• Period C (verification period) from t up to t +48 h for verification of equilibrium condition.
0+44 h 0
Measure pH in the liquid after each of these periods.
The total contact period (A+B+C) is 48 h.
8.2 pH-range
The test shall cover the range pH 4 to pH 12 (both included i.e. the lowest value ≤4 and the highest value ≥12) with
at least 8 pH values tested including the natural pH (without acid or base addition). The maximum difference
between two consecutive pH values shall not exceed 1,5 pH units.
NOTE 1 To ensure that the appropriate pH values can be obtained in one run additional bottles can be prepared.
NOTE 2 The pH range covered by the test may be restricted to a pH range relevant for the specific material and the considered
problem. The pH range to be covered can depend on the specific properties of the material, the available information on this
material and the questions to be answered by performing the test. The number of pH levels considered can be reduced,
correspondingly.
8.3 Acid-, base neutralization capacity test
8.3.1 General
The following procedure applies for each of the chosen pH values to be tested.
8.3.2 Preparation of leachant
+
Estimate the acid or base consumption needed to reach the relevant pH values as A (mol H /kg DM) or B (mol
+
H /kg DM).
NOTE 1 An estimate of the acid or base consumption for the considered pH values may be derived from available literature
information, from the preliminary procedures in Annex B or from information in Annex C.
Calculate the volume V of liquid to establish L/S = 10 l/kg ± 0,2 l/kg for the actual size of test portion M (see 7.4)
w
including the volume of acid or base.
V = 10 × M (3)
d
where
V is the total volume of liquid in the test in ml;
M is the dry mass of the test portion expressed in grams (g) (see 7.4).
d
NOTE 2 In relation to L/S-ratio, V in this equation is equivalent with the ”L” and M is equivalent to the “S”.
d
Calculate the amount of leachant to be added to the actual size of test portion and compensate for the moisture
content in the test portion, as follows:
V = V − ( − 1) × M (4)
L d
w
dr
where
V is the total volume of liquid in the test in ml;
M is the dry mass of the test portion expressed in grams (g) (see 7.4);
d
w is the dry residue of the waste expressed as percentage % (see 7.3);
dr
V is the volume of leachant to be added expressed in milliliters (ml).
L
Prepare the leachant from de-mineralized water (see 6.1.1) and acid or base (see 6.1.2 or 6.1.4) according to the
acid/base consumption for the relevant pH.
Prepare the acid adjusted leachant as follows:
V = V +V (5)
L demin A
A × M
d
V = (6)
A
C
A
where
V is the volume of prepared leachant expressed in milliliters (ml);
L
V is the volume of demineralised water used expressed in milliliters (ml);
demin
V is the volume of acid needed expressed in milliliters (ml);
A
+
A is the acid consumption for the pH in mol H /kg DM;

M is the dry mass of the test portion expressed in grams (g) (see );
7.4
d
C is the concentration of the acid expressed in mol per liter (m/l) (see 6.1.2).
A
Prepare the base adjusted leachant as follows:
V =V + V (7)
L demin B
B × M
d
V = (8)
B
C
B
where
V is the volume of prepared leachant expressed in milliliters (ml);
L
V is the volume of demineralised water used expressed in milliliters (ml);
demin
V is the volume of base needed expressed in milliliters (ml);
B
+
B is the base consumption for the pH, mol H /kg DM;

M is the dry mass of the test portion expressed in grams (g) (see 7.4);
d
C is the concentration of the base expressed in mole per liter (mol/l) (see 6.1.4).
B
Split the volume V of leachant into 3 equal fractions V /3.
L L
8.3.3 Procedure
Carry out the test at a temperat
...