The Time-Varying Variation Characteristics of Methane during Nitrogen Injection Process: An Experimental Study on Bituminous Coals

Table 2

Data standardization results under different pressures.

Code	Injection pressure (MPa)	Displacement efficiency (%)	Standardized processing	Replacement ratio	Standardized processing
1	0.5	52.3	0	10.9	1
2	1	55.9	0.89	10.2	0.16
3	1.5	62.9	0.32	9.1	0.57
4	2	79.9	0.16	7.2	0.88
5	2.5	85.2	1	6.7	0