Nuclear power plant battery acid protection system

In accordance with the requirements of the AP1000 technical specification of the third generation nuclear power plant imported from the United States, the battery anti-spill acid container (acid spill tank) is a product specifically based on the battery room of nuclear power plant. Domestic from the Sanmen phase I, Haiyang phase I, Xu Dabu phase I nuclear power plant project, from the United States Westinghouse company supporting the introduction of battery room anti-spill acid system. In order to break the foreign technology monopoly, our company cooperated with relevant personnel and units to develop it; In the process of product development, we have absorbed the advantages of relevant foreign products and made corresponding improvements according to their shortcomings. In the process we also made inventions and applied for state zhuanli (zhuanli No. 201420071159.8 has been approved, the second zhuanli is under application).

In order to better ensure the overall safety and reliability of the battery system of nuclear power projects, reduce or even avoid the damage of spillover sulfuric acid to the environment, a method is needed to reduce or even eliminate the corrosion of sulfuric acid as soon as possible. Each element of the spill control system is specifically designed to be used as a passive neutralization system to absorb and neutralize liquids containing sulfuric acid to maintain an acceptable pH level.

Its main materials and components are as follows:

1. Acid and corrosion resistant lining board.

2. Neutralize and absorb pillows.

3. Acid proof fence support wall with warning yellow (coated with acid proof coating).

Performance testing and testing of key components of the spill prevention system, including but not limited to the absorption pillow:

Flame retardancy, absorption, neutralization.

After analyzing the acid sputtering tank systems of Sanmen Phase I, Haiyang Phase I and Xudabu Phase I of foreign counterparts, we have made the following improvements:

1. The acid-resistant anti-corrosion lining board is replaced by the original rubber with acid-proof flame-retardant cloth. Acid-proof flame-retardant cloth does not contain PVC;

2. The acid-base indicator is added to the new neutralization material formulation, which can simply judge the neutralization reaction result according to the color of the residue by the naked eye as the basis for follow-up work; It is also convenient to protect the safety of on-site personnel and prevent operators from accidentally contacting acid and alkali substances;

3. For the key alkaline neutralizing materials, we have adopted a special formula, specifically for the electrolyte of lead-acid batteries, that is, dilute sulfuric acid with a concentration of about 30%. The neutralizing material can absorb water and a lot of heat generated when dilute sulfuric acid, and further absorb heat to control the temperature rise within 30℃, but also can quickly absorb water to prevent the diffusion of dilute sulfuric acid;

4. The main material of acid-absorbing pillow is alkaline neutralizing powder. The alkaline neutralizing powder comprises a neutralizing agent, an auxiliary agent, a heat absorbent, a water absorbent, a dispersant, an acid-base indicator, a leavening agent, etc. The material with acid-lye adsorption function is made into a bag, and the alkaline neutralizing powder is packed. We also specially commissioned the Chemical Fiber Engineering Research Center of Donghua University to test the rationality and effectiveness of this formula and provide a report;

5. The alkaline neutralizing material has been found to decrease the neutralization rate in many tests, and the accumulation of substances formed after the neutralization of sulfuric acid on the surface will prevent the further formation of neutralization. According to the problems found, surfactants and bulking agents were added specially to speed up the absorption of sulfuric acid and improve the neutralization efficiency.

6. For the packaging materials of alkaline neutralizing materials, we use flame-retardant chemical adsorption cotton. The relevant test report is shown in the attached figure.

In short, the improved domestic acid spillage tank has absorbed the advantages of related products of foreign counterparts, and has made a lot of improvements. The final product has been greatly improved in terms of durability, convenience, reliability and economy.