Solution for detecting furfural in transformer oil

PREFACE

Oil immersed transformer is one of the main equipment in the power grid system, which contains a large amount of insulation oil and insulation paper. Over time, insulation oil and paper will gradually age, and the insulation effect will deteriorate, affecting the effectiveness and safety of transformer use. Insulation oil can be regenerated or replaced during the use of transformers, but the aging of insulation paper cannot be restored. The aging degree of insulation paper is an important indicator to determine whether the transformer needs to be replaced.

At present, the paper insulation material for domestic power transformers is mainly made of wood pulp, with cellulose as the main component. When the insulation paper deteriorates, cellulose degrades to produce a portion of D-glucose monomers, which are easily decomposed under the operating conditions of the transformer. Finally, a series of oxygen heterocyclic compounds dissolved in the transformer oil are produced, and furfural is a major oxygen heterocyclic compound formed after the degradation of cellulose macromolecules.

Qualified new transformer oil does not contain furfural, and the aging of non cellulose insulation materials inside the transformer does not produce furfural. The furfural in transformer oil is a product only generated by the aging of paper insulation. Therefore, testing the furfural content in oil can reflect the aging condition of transformer paper insulation.

Instruments, equipment, and reagents

Furfural liquid chromatography in transformer oilStandard configuration list

Serial Numbernamequantity

1High pressure constant flow pump2 units

2UV detector1 unit

37725i high-pressure six way injection valve1 piece

4Valve bracket1 piece

5Chromatographic data workstation1 set

6Solvent tray1 unit

7Specialized chromatographic column1 拫

8Instrument Startup Kit1 set

9Micro injection needle1 unit

10Organic filter membrane1 box

111 set of high-pressure mixer

121 vortex oscillator

13 4000r centrifuge 1 set

1 set of 14 vacuum pumps

151 ultrasonic wave

161 set of sand core filter

1 set of 17 column temperature box

Experimental methods

solution preparation

Preparation of reference solution

Accurately weigh 250.4mg of furfural standard and add toluene to a 25mL volumetric flask to make up to volume. Accurately measure 1.0mL of the solution and add it to a 10mL volumetric flask. Dilute with toluene and make up to volume to prepare a stock solution of furfural standard with a concentration of 1001.6mg/L.

Accurately measure 100 μ L of furfural standard stock solution, add it to a 10mL volumetric flask, dilute with methanol and make up to volume to prepare a methanol solution of furfural with a concentration of 10.0mg/L. Take the solution separately and dilute it with methanol to a certain volume to prepare a series of standard solutions with furfural concentrations of 10.0, 20.0, 40.0, 60.0, and 100.0 μ g/L.

Preparation of test sample solution

Accurately measure 20 mL of transformer old oil for testing into a 60 mL separatory funnel. Accurately measure 2.5 mL of methanol and add it to the funnel. Shake, extract, and let it stand for about 15 minutes. Take the methanol extract (upper clear liquid) and filter it to obtain the test solution.

Chromatographic conditions

Chromatographic column: C18 column mobile phase composition (V/V): A phase

Traffic: 1.0mL/min

Injection volume: 20μL

testing: UV274nm

Methanol/water=10/90; B phase, methanol

Experimental results

Typical Separation Chromatogram

Inject a standard solution of furfural with a concentration of 100.0 μ g/L and analyze it according to the chromatographic conditions in section 2.2. The results are shown in the following figure:

After sales service
Our company sellsFurfural liquid chromatography in transformer oilAccording to relevant national laws and regulations Implement product repair, replacement, and return packages The instrument and equipment are uniformly guaranteed for one year, with lifelong maintenance and upkeep Free installation and debugging Train operators Receive user feedback and respond promptly If necessary, promptly come to the door to solve the problem

Main business of Zhongkepu Company

1. Free consultation, diagnosis, and resolution of hardware issues
2. On site service and provision of consumables for maintenance
3. Regularly hold training courses on chromatographic analysis applications and chromatographic maintenance
4. Assist you in establishing a chromatographic analysis laboratory and chromatographic analysis methods, and train chromatographic operators
5. Undertake the installation, commissioning, maintenance and repair of various analytical instruments such as gas chromatography, liquid chromatography, ultraviolet spectroscopy, liquefied gas analyzer, Baijiu analyzer, etc
6. Undertake chromatographic analysis tasks and provide performance testing reports
7. Main products: gas chromatograph; Liquid chromatograph; Liquefied gas analyzer; Baijiu chromatograph; Transformer oil spectrophotometer; Solvent residue chromatography analyzer; Pesticide residue analyzer; Natural gas analyzer; Dimethyl ether detector; Gas chromatography consumables; Nitrogen hydrogen air generator; Fill the chromatographic column; Liquid chromatography column; Chromatographic accessories; Gas chromatography valve; Headspace bottle;Gas purifier; Deoxygenation tube; Pressure clamp; Gasification pad; Micro injector; Capillary/filling column graphite pad; Flat gas injection six way valve, etc