An Optimization Model Based on Electric Power Generation in Steel Industry

Table 2

Meanings and units of variables in the model.

Nomenclature
Subscripts
𝑡	Unit of time, h
𝑚	Power generation and steam production equipment
𝑖	Kinds of gas (BFG, COG, and LDG)
𝑘	Kinds of steam (S1, S2, and S3)
Variables
𝐶^elebuy,𝑡	Price of outsourcing electricity in 𝑡 time point, RMB/kW·h
𝐶^elegen,𝑚	Price of self-generation of device 𝑚, RMB/kW·h
𝐶^coal	Price of outsourcing coal, RMB/𝑡
𝐶^gas𝑖	Price of 𝑖 gas, RMB/m^3
𝐶^ste𝑚,𝑘	Cost of 𝑘 steam production device 𝑚, RMB/𝑡
𝐶^Gas𝑖	Punishment price of 𝑖 gas, RMB/m^3
𝐷^ele𝑡	Power demand of 𝑡 time point, kW·h
𝐷^ste𝑘,𝑡	𝑘 steam production demand of 𝑡 time, 𝑡/h
𝐵𝑖,𝑡	𝑖 gas surplus of 𝑡 time, m^3/h
𝐸𝑚	Rated generating capacity of equipment 𝑚, kW
𝐴𝑚	Steam production quantity of equipment 𝑚, 𝑡/h
𝐹^min𝑚,𝑖	Adjust lower limit of equipment 𝑚 gas-fired 𝑖, m^3/h
𝐹^max𝑚,𝑖	Adjust upper limit of equipment 𝑚 gas-fired 𝑖, m^3/h
ℎ^ele	Calorific value of the electricity, kJ/kW·h
ℎ^ste𝑘	Calorific value of 𝑘 steam, kJ/kg
ℎ^gas𝑖	Calorific value of 𝑖 gas, kJ/m^3
ℎ^coal	Calorific value of heating coal, kJ/kg
𝜂𝑚	System generating (thermal) efficiency of equipment 𝑚, %
𝑅𝑚,𝑡	Caloric value of recovery of residual heat and energy resources of equipment 𝑚 in 𝑡 time, kJ/h
𝐸^buy𝑡	Outsourcing electricity of 𝑡 time point, kW
𝐸^gen𝑚,𝑡	Generation capacity of equipment 𝑚 in 𝑡 time point, kW
𝑓𝑚,𝑡	Consumption of equipment 𝑚 in 𝑡 time point, 𝑡/h
𝐹𝑚,𝑖,𝑡	Consumption of 𝑖 gas equipment 𝑚 in 𝑡 time point, m^3/h
𝑄𝑚,𝑘,𝑡	Production quantity of 𝑘 steam equipment 𝑚 in 𝑡 time, 𝑡/h
𝐹^Gas𝑖,𝑡	Emission capacity of 𝑖 gas in 𝑡 time point, m^3/h
𝐴𝑚,𝑘	Extraction quantity of equipment 𝑚, 𝑡/h