Project according to currently China PVDF of production status and market development prospects, determine PVDF production scale for 5000 tons/years, production PVDF by needed 13,000 tons/years R142b and 7300 tons/years VDF of supporting device earlier construction, using partial chlorine vinyl and HF first by fluoride of reaction get rough II fluoride chlorine ethane (R142b), by fine distillation get fine R142b, again by R142b cracking, and cracking gas washing, and compression, and fine distillation, get products partial fluoride vinyl.