What is the background of "Hou Shi Soda Process"?

In the 1920s, the most advanced soda production method in the world was the Solvi soda production method monopolized by Solvi Company. 192 1 year, in order to change the backward state of soda ash industry in China, industrialists from China were invited to graduate from MIT, work as engineers and set up soda ash plants. It took Hou Shi only four years to imitate Su Wei's method to produce soda ash with purity over 99%. Later, in order to improve the utilization rate of salt and reduce the cost of raw materials, Li Yong Soda Factory planned to purchase the German patent of "Tea Temple Law". The harsh conditions of the other side angered Hou Yi, who loved the motherland. After several years' efforts, he finally succeeded in creating "Hou Shi Soda Process" in 194 1.