How many are there in the old factory area of Mianyang meifeng?

Mianyang meifeng Old Factory is an old industrial factory in Mianyang City. Due to historical reasons, there are many old factories now, including the old factory in meifeng. Specifically, the known Mianyang meifeng Old Factory mainly includes the following types: 1, meifeng Old Factory Phase I: located in Huang Yu Town, Fucheng District, Mianyang City, it is one of the earliest chemical plants in Mianyang City, which was founded in the early 1960s and mainly produces chemical products such as dyes and pigments. 2. meifeng Old Factory Phase II: Located in the northwest of Baiyang Town, Fucheng District, Mianyang City, it is the expansion area of meifeng Old Factory. Founded in the early 1970s, it mainly produces ammonium phosphate, sodium hydroxide, sodium sulfate and other products. 3. meifeng Old Factory Phase III: Located in Huang Yu Town, Fucheng District, Mianyang City, it was built in the 1980s and is the expansion area of meifeng Old Factory, mainly producing plastic, rubber and other products. 4. meifeng Old Factory Phase IV: Located in Baohua Town, Fucheng District, Mianyang City, it was built in the 1990s and mainly produces polymer materials, dyes, pigments and other products. The old factory area refers to the old industrial area in the city, which usually refers to the industrial area established from the beginning of last century to the 1980s and 1990s. At that time, these industrial zones were important industrial supports for urban development and contributed to urban economic and social development. However, with the adjustment of economic structure and the acceleration of urbanization, these old industrial areas gradually lose their attraction, the industrial structure needs to be upgraded urgently, and the building facilities are aging gradually, which has become the difficulty and bottleneck of urban management and development.