Kjeldahl nitrogen analyzers play a crucial role in laboratories, facilitating the accurate determination of nitrogen content in various substances. However, like any complex instrument, these analyzers can encounter issues during operation. This article aims to provide a comprehensive guide to common problems associated with Kjeldahl nitrogen analyzers and practical solutions to address them.

Violent Rolling During Distillation:

Issue: The Kjeldahl nitrogen analyzer rolls violently during distillation.

Solution: This is typically caused by a large amount of water vapor entering the digestive tube. While it may appear concerning, the Kjeldahl nitrogen analyzer is equipped with an overpressure protection device to maintain safe internal pressure.

Water Quality Requirements:

Issue: What are the water quality requirements for the Kjeldahl nitrogen analyzer?

Solution: Use distilled water or pure water in the distilled water barrel. If the analyzer is unused for an extended period, release the water in the distiller.

No Sound When Turned On:

Issue: The Kjeldahl nitrogen analyzer produces no sound when turned on.

Solution: Check if the red light on the power switch is on. If the fuse is blown, locate it in the black case 5 cm away from the power switch interface inside the machine.

Failure to Add Water to the Distiller:

Issue: The Kjeldahl nitrogen analyzer does not add water to the distiller after being turned on.

Solution: Check for leaks in the distilled water bucket, ensure the water level is sufficient, and verify correct connections. Confirm that the drain valve is closed.

Steamer Not Heating:

Issue: The steamer of the Kjeldahl nitrogen analyzer does not heat and cannot produce steam.

Solution: If alkali can be added but no steam is produced, the heating wire may be burnt out. Use a multimeter to check the positive and negative electrodes.

Loud Working Sound:

Issue: The Kjeldahl nitrogen analyzer produces a loud working sound.

Solution: This is a normal sound resulting from the air pump inside the analyzer.

Failure to Add Alkali:

Issue: The Kjeldahl nitrogen analyzer cannot add alkali, and there is no sound during the process.

Solution: Check for alkali barrel leaks and ensure the machine operates normally when inflated with air. If the analyzer has been in use for a long time, crystallization inside the alkali pipe may impede flow.

Smoke-Like Gas Emission:

Issue: Smoke-like gas comes out from the top during operation.

Solution: Ensure the cooling water inlet faucet is open. Closed or low water volume can result in uncondensed steam, creating the appearance of smoke.

Sucking Back of White Tube:

Issue: The white tube in the digestive tube sucks back during operation.

Solution: Check if the gas valve closes promptly when the Kjeldahl nitrogen analyzer stops working. If not, pierce small holes in the white tube or replace the faulty air valve.

Regular Sound Every 3-5 Seconds:

Issue: The Kjeldahl nitrogen analyzer makes a sound every 3-5 seconds during operation.

Solution: This periodic sound is normal. It occurs as the distiller continues to heat, generating water vapor, and the machine automatically opens the water valve to replenish water.

Conclusion

Troubleshooting common problems in Kjeldahl nitrogen analyzers involves a systematic approach to identify and address issues promptly. By understanding the potential challenges and implementing the provided solutions, operators can ensure the reliable and efficient performance of these essential laboratory instruments. Regular maintenance and adherence to operational guidelines contribute to the longevity and accuracy of Kjeldahl nitrogen analyzers in analytical processes.