1、Recommended best practice for the analysis of total nitrogen content in

These methods are based on nitrogen releases from fertilizer products through high-temperature combustion with oxygen, followed by measurement using thermal conductivity detection.

2、(PDF) An Overview of the Kjeldahl Method of Nitrogen Determination

The Kjeldahl method was introduced in 1883 and consists of three main steps: sample digestion, distillation, and ammonia determination (titration being the primary method).

3、Development and Testing of Intelligent Sensing and Precision

In this research, new concept of an intelligent sensing system was proposed， and accurate proportioning system of water and fertilizer concentration was constructed and implemented.

4、Kjeldahl Method

The two primary lab-based measures to assess nitrogen content are the wet-chemistry based Kjeldahl method in which samples are ground and then diluted and distilled, and the Dumas method, which uses sample combustion at high heat.

Kjeldahl's Method: Principle, Reaction, Formula and Limitations

It is used in agriculture to estimate the nitrogen content in fertilizers. The method will be explained in this article from its principles and procedures. Then, we would be able to point out the many different aspects of nitrogenous compounds that can be analyzed through this process.

Kjeldahl Method: Principle, Steps & Formula for Nitrogen

Learn the Kjeldahl method with clear principle, steps, and example calculations for nitrogen and protein estimation. Exam-ready guide with formula, applications & tips.

Total Nitrogen Application Note

Analytically, ammonia and organic nitrogen can be determined together using a technique called Total Kjedahl Nitrogen (TKN). In the past, to arrive at an accurate assessment of total nitrogen, the analyst had to separately measure for all of the various nitrogen forms and then combine the results.

Dumas method for nitrogen and protein determination

Fully automated analytical systems such as the N-Realyzer use the basic principles of the Dumas method for the determination of nitrogen and protein content in solid and liquid samples.

Determination of nitrogen in solid and liquid fertilisers

In the Dumas method, the nitrogen contained in the sample is oxidized to nitrogen oxides in an oxygen atmosphere, at high temperatures and in the presence of a catalyst.

Methods of increasing the productivity of precision batch proportioning

At the present time, high-productivity precision proportioning of granular materials is performed with the use of one of three methods. The first method, summation of batches [1], is based on partitioning of an entire batch into small batches (usually 10–30).

The proportioning method for liquid high-nitrogen fertilizers involves mixing nitrogen, phosphorus, and potassium sources in varying ratios to provide essential nutrients for plant growth. This approach is widely used in agriculture because it enhances fertilizer utilization, reduces environmental pollution, and improves crop yields and quality.

The principle of this method primarily revolves around adjusting the concentrations of nutrients such as nitrogen (N), phosphorus (P), and potassium (K) to meet plants' nutritional needs at different growth stages. The specific principles are as follows:

1. Principle of Nutrient Element Balance: Plants require multiple nutrients, including nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. The proportioning method balances these elements to match plants' growth demands. For example, liquid high-nitrogen fertilizers can supplement soil nitrogen deficits, while liquid high-phosphorus fertilizers address phosphorus shortages.

2. Principle of Plant Physiological Response: Nutrient absorption and utilization by plants are complex physiological processes. Adjusting the concentrations of N, P, and K in liquid fertilizers influences how plants absorb these elements, thereby affecting their growth. For instance, increasing nitrogen levels in the fertilizer meets plants' higher nitrogen demands during specific growth phases.

3. Principle of Fertilizer Response Curves: By optimizing nutrient concentrations, the method aligns fertilizer application with the "response curve"—the relationship between fertilizer dosage and crop yield/quality. This ensures economical and efficient use of fertilizers while minimizing environmental impact.

4. Principle of Soil Nutrient Balance: The method regulates soil fertility by balancing nutrient levels. For example, excessive soil nitrogen can be mitigated by adjusting liquid high-nitrogen fertilizer ratios, while low phosphorus levels can be corrected by adding liquid high-phosphorus fertilizers.

5. Principle of Environmental Sustainability: This method reduces chemical fertilizer usage, lowering pollution risks to groundwater, soil, and air. It also minimizes nutrient runoff and leaching, improving fertilizer efficiency.

the liquid high-nitrogen fertilizer proportioning method is a scientific and rational approach. By tailoring nutrient ratios to plants' growth stages, it enhances fertilizer efficiency, reduces environmental harm, and boosts crop productivity and quality. Promoting this method in agriculture holds significant importance.