GB/T 31246-2025Water treatment chemicals - Cationic polyacrylamides (English PDF)

Foreword

This document was drafted in accordance with the rules provided in GB/T 1.1-2020 Directives for Standardization - Part 1: Rules for the Structure and Drafting of Standardizing Documents.

This document serves as a replacement for GB/T 31246-2014 Water Treatment Chemicals - Technical Specification and Test Method of Cationic Polyacrylamides. In comparison with GB/T 31246-2014, apart from structural adjustments and editorial modifications, the main technical changes are as follows:

---The structural formula is modified (see Chapter 4; Chapter 3 of Version 2014);

---Table 1 is modified, deleting the indicators of relative molecular mass, sulfate (SO4) content, and chloride (Cl) content, adding the indicators of intrinsic viscosity and residue on ignition, and modifying the indicators of solid content, water-insoluble matter, and sieve residue (see Table 1; Table 1 of Version 2014);

---The test solution preparation method and calculation formula for intrinsic viscosity are modified (see 6.3.4.2 and 6.3.5; 5.2.4.2 and 5.2.5 of Version 2014);

---The relation between etar and [eta]c is deleted (see Table 2 of Version 2014);

---The determination method and calculation formula for cationic degree are modified (see 6.4; 5.3 of Version 2014);

---The method for determining the content of acrylamide monomer is modified from the single-point method to the working curve method (see 6.6; 5.5 of Version 2014).

Please be noted that certain content of this document may involve patents. The issuing institution of this document does not undertake the responsibility of identifying these patents.

1 Scope

This document specifies the requirements, inspection rules, marking, packaging, transportation, and storage of cationic polyacrylamide as water treatment chemicals, and describes the corresponding test methods.

This document applies to cationic polyacrylamide products used as water treatment chemicals.

NOTE: this product is mainly used for flocculation treatment of industrial water and wastewater, as well as sludge dewatering treatment.

2 Normative References

The contents of the following documents constitute indispensable clauses of this document through the normative references in the text. In terms of references with a specified date, only versions with a specified date are applicable to this document. In terms of references without a specified date, the latest version (including all the modifications) is applicable to this document.

GB/T 191 Graphical Symbols Marking for Handling and Storage of Packages

GB/T 602 Chemical Reagent - Preparations of Standard Solutions for Impurity

GB/T 603 Chemical Reagent - Preparations of Reagent Solutions for Use in Test Methods

GB/T 6003.1 Test Sieves - Technical Requirements and Testing - Part 1: Test Sieves of Metal Wire Cloth

GB/T 6678 General Principles for Sampling Chemical Products

GB/T 6682-2008 Water for Analytical Laboratory Use - Specification and Test Methods

GB/T 7531 Determination of Ignition Residue for Organic Chemical Products

GB/T 8170 Rules of Rounding off for Numerical Values & Expression and Judgement of Limiting Values

3 Terms and Definitions

This document does not have terms or definitions that need to be defined.

4 Structural Formula

Where, m >= 1, n >= 1; R = H or CH3.

5 Requirements

5.1 Appearance. cationic polyacrylamide, as water treatment chemicals, is white or slightly yellow granule or powder.

5.2 Relative molecular mass. provided in accordance with user requirements. The calculation method is given in Appendix A.

5.3 The cationic polyacrylamide, as water treatment chemicals, which is determined in accordance with the corresponding test methods, shall meet the requirements of Table 1.

6 Test Methods

WARNING: the strong acid used in this document is corrosive. During use, avoid inhalation or skin contact. If splashed on the skin, immediately rinse with plenty of water. In severe cases, immediately seek medical attention.