ASTM C400-19 (2024)e2 PDF

Full title and description

St ASTM C400-19 (2024)e2 — Standard Test Methods for Quicklime and Hydrated Lime for Neutralization of Waste Acid. This standard describes laboratory test methods and procedures used to characterize quicklime and hydrated lime and to determine their neutralizing effectiveness when used to treat acidic waste solutions. It includes definitions, apparatus and reagent specifications, step-by-step test procedures (including pH measurement and titration approaches), and guidance for reporting results such as neutralization coefficient and acid value.

Abstract

ASTM C400 provides standardized test methods to evaluate the neutralization capacity of liming materials (quicklime and hydrated lime) against waste acids. The methods yield comparative measures — including neutralization coefficient, lime requirement, and acid value — that help producers, waste-treatment facilities, and environmental laboratories select and dose lime for neutralization processes. The 2019 edition (C400‑19) has editorial updates reflected in the 2024 e2 release.

General information

• Status: Active (current edition with editorial changes).
• Publication date: Current designation: C400‑19 (original approval December 1, 2019); editorial change e2 issued in 2024 (e2 editorial update).
• Publisher: ASTM International.
• ICS / categories: 91.100.10 — Cement. Gypsum. Lime. Mortar (Lime and limestone products and test methods).
• Edition / version: C400 − 19; editorial revision e2 (2024).
• Number of pages: 3 (concise test method document).

Scope

This standard covers test methods for quicklime and hydrated lime intended for neutralization of waste acid solutions. It specifies procedures to determine the neutralization coefficient (relative liming power), to measure acid value of waste acid, and to evaluate lime requirement under defined test conditions (pH, time, temperature, and mixing). The procedures may be adapted to plant practice by agreement between purchaser and supplier but otherwise are to be performed as published. The standard does not address all safety or regulatory requirements associated with use.

Key topics and requirements

• Definitions relevant to lime testing (neutralization coefficient, acid value, lime requirement).
• Apparatus and apparatus specifications (pH glass electrode and recorder or time‑pH device, stirrers, analytical balances, specified sieves/no. 50 and no. 100, etc.).
• Reagents, units (SI preferred), and sample preparation requirements including sieving and representative sampling practices (reference to ASTM sampling practice where applicable).
• Test procedures to determine neutralization coefficient expressed as grams CaO equivalent per kilogram of liming material under a defined acid concentration and test interval.
• pH measurement and titration techniques (reference to standard pH methods) and guidance on reporting liming material basicity and waste acid acid value.
• Reporting requirements: neutralization coefficient, lime requirement for a specified acid, test conditions (pH end point, time, temperature), and any deviations from plant practice.
• Referenced standards and cross‑references (sampling, terminology, pH measurement, sieve specifications).

Typical use and users

Used by environmental testing laboratories, lime and chemical suppliers, wastewater and industrial waste‑treatment facilities, process engineers, and regulatory or compliance laboratories. Typical applications include selecting and dosing liming agents for neutralization of acidic wastes, quality control of lime products, product specification compliance, and comparative evaluation of liming materials for treatment design.

Related standards

ASTM standards commonly associated with C400 include: Practice for Sampling, Sample Preparation, Packaging, and Marking of Lime and Limestone Products (C50/C50M); Terminology Relating to Lime and Limestone (C51); Test Method for pH of Aqueous Solutions with the Glass Electrode (E70); sieve specification (E11); and related lime specifications and test methods such as C911 and C977. Users frequently consult these documents for sampling, terminology, pH methodology, and product specifications.

Keywords

quicklime, hydrated lime, neutralization, waste acid, acid value, neutralization coefficient, lime requirement, pH measurement, liming material, lime testing, ASTM C400

FAQ

Q: What is this standard?

A: ASTM C400 is a concise set of laboratory test methods for evaluating the neutralizing performance of quicklime and hydrated lime when treating acidic waste solutions.

Q: What does it cover?

A: It covers definitions, required apparatus and reagents, sample preparation, stepwise procedures to determine neutralization coefficient and lime requirement, pH measurement guidance, and reporting conventions. It is intended for comparative evaluation and practical dosing guidance rather than prescribing treatment‑plant design.

Q: Who typically uses it?

A: Environmental and process laboratories, lime manufacturers and suppliers, industrial waste‑treatment operators, process engineers, and agencies overseeing waste‑treatment compliance.

Q: Is it current or superseded?

A: The base document is C400‑19 (approved December 1, 2019) and the designation shown includes editorial updates designated e2 issued in 2024. The standard is currently active; users should confirm the edition required by contract or procurement and check for any later revisions or reapprovals.

Q: Is it part of a series?

A: Yes. C400 is part of ASTM Committee C07 (Lime and Limestone) publications and is linked to a suite of C‑series standards covering sampling (C50/C50M), terminology (C51), and related specifications and test methods for lime products (for example C911, C977).

Q: What are the key keywords?

A: Quicklime, hydrated lime, neutralization coefficient, lime requirement, waste acid, acid value, pH, liming material.