Question: Purity Control: How to ensure that materials inside the furnace do not contaminate products, meeting high purity requirements (such as low metal impurities)?

Detailed Answer:

For high-end applications (such as semiconductors, nuclear-grade materials, and advanced anode materials), products have stringent requirements for metal impurity content, sometimes at ppm or even ppb levels. Ensuring that the graphitization furnace does not become a source of contamination is critical. We address this issue from the source through a rigorous high-temperature empty burning purification process.

I. Analysis of Contamination Sources

New graphite heating elements, insulating graphite felt, and other components may adsorb or contain trace amounts of metal impurities, moisture, and ash during the manufacturing process. These substances can volatilize at high temperatures and contaminate the products.

II. Core Purification Measure: High-Temperature Empty Burning

Before formal production begins, every new furnace—or after replacing major graphite components—must undergo multiple rounds of high-temperature empty burning purification.

Process Procedure:

1. Heat the empty furnace (without any products) according to a specific program to the maximum operating temperature or even slightly higher.

2. Maintain the temperature for an extended period, allowing all graphite components and insulation materials inside the furnace to undergo a thorough "baking."

3. During this process, volatile impurities on the surface and inside the materials are fully released and carried out of the furnace by the flowing protective gas or vacuum system.

Effectiveness Verification: After 2-3 rounds of high-temperature empty burning, the impurity content inside the furnace drops to an extremely low level. We can verify the purification effect through blank tests (sampling and analysis after empty burning).

III. Guarantees Provided to Customers

• Pre-Delivery Treatment: Our equipment undergoes preliminary empty burning purification before leaving the factory.

• On-Site Guidance: After on-site installation and commissioning, our engineers guide customers through the final purification process to ensure the equipment meets the requirements for producing high-purity products.

• Process Recommendations: We provide corresponding empty burning process specifications for products with different purity requirements.

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