The project of 'preparation technology of mineral heavy metal passivator and its implementation effect in polluted farmland' undertaken by Prof. Shi lin and others, has passed the provincial and ministerial level achievement appraisal in December 2017. The project carried out farmland test in three heavy metal polluted areas in the Pearl River Delta, and completed the third-party technology achievement evaluation. The conclusion is that the technology of preparing passivator from active natural minerals to treat heavy metal contaminated soil is a principle innovation. The achievements belong to the first domestic technology, and the overall technical innovation is the principle innovation; the technology of one-time adsorption of main heavy metal ions and the retention rate at pH = 3.5 reach the international leading level.

It can not only reduce the content of heavy metals in agricultural products, but also adjust the soil acid-base balance, inhibit the leaching of aluminum ions in the soil, improve the soil structure, increase the soil moisture value, reduce the soil water loss, and improve the water and fertilizer utilization rate.