GB/T 20412-2021Fused calcium magnesium phosphate fertilizer (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document replaces GB/T 20412-2006 "Calcium Magnesium Phosphate Fertilizer". Compared with GB/T 20412-2006, except for editorial changes, the main technical The technical changes are as follows.

---Added the types of granular products, their size, average crush resistance and dissolution rate indicators (see 4.3) and test methods (See 6.10, 6.11, 6.12);

---Changed the name and value of the alkali index (see 4.2 and 4.3, 3.2 in the 2006 edition);

---Increase the effective magnesium content, soluble silicon content index (see 4.2 and 4.3) and plasma emission spectrometry (ICP-OES) determination Test methods for available calcium, available magnesium, and soluble silicon (see 6.6.2, 6.7.2, 6.8.2);

--- Increased the limit requirements for toxic and hazardous substances in products (see 4.4);

---The flow analyzer method is added to determine the effective phosphorus pentoxide content (see 6.4.3).

1 Scope

This document specifies the terms and definitions, requirements, test methods, inspection rules, labeling, packaging, transportation and storage of calcium magnesium phosphate fertilizers.

This document is applicable to phosphate rock and ore containing magnesium and silicon, which are prepared by high-temperature melting, water quenching, drying and other processes containing phosphorus, calcium, magnesium, Alkaline glassy fertilizers with nutrients such as silicon, and granular products that are granulated into balls by adding additives in the production.

2 Normative references

The contents of the following documents constitute the indispensable clauses of this document through normative references in the text. Among them, dated quotations Only the version corresponding to that date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 6003.1 Technical requirements and inspection of test sieves Part 1: Metal wire woven mesh test sieves

GB/T 6679 General Rules for Sampling of Solid Chemical Products

GB/T 6682 Analytical laboratory water specifications and test methods

GB/T 8170 Numerical rounding rules and the expression and determination of limit values

GB/T 8569 Solid chemical fertilizer packaging

GB 18382 Fertilizer labeling content and requirements

GB/T 22923 Determination of Nitrogen, Phosphorus and Potassium in Fertilizers by Automatic Analyzer

GB/T 24891 Determination of particle size of compound fertilizer

GB 38400 Limit requirements for toxic and hazardous substances in fertilizers

HG/T 2843 Commonly used standard titration solution, standard solution, reagent solution and indicator solution for chemical analysis of fertilizer products

3 Terms and definitions

The following terms and definitions apply to this document.

4 Requirements

4.1 The appearance is powdery or sandy or granular, without mechanical impurities.

4.2 The technical indicators of powdered or sandy calcium-magnesium phosphate fertilizers should meet the requirements of Table 1, and should meet the indicated values.