At present, sulfuric acid is often used as catalyst in fatty acid methyl esterification process. Although the reaction conditions are mild, sulfuric acid will corrode the equipment and produce solid waste and waste water, which is not friendly to the environment. The solid acid esterification technology developed by our company adopts continuous production of catalytic distillation, which is easy to operate, without solid waste and waste water, and has no pollution to the environment. The picture shows the industrial unit of Yixing sanmufuhong using our company's solid acid esterification technology, which is the first set of solid acid esterification industrial device in China.