双欣环保：公司拥有年产200万吨的石灰石矿

Group 1 - The core viewpoint of the article is that Shuangxin Environmental Protection has a limestone mine with an annual production capacity of 2 million tons, which provides raw materials for the company's calcium carbide production [2] Group 2 - The company emphasizes the importance of its limestone mine in supporting its production processes [2] - The interaction with investors highlights the company's commitment to transparency and communication regarding its operational capabilities [2]