Decreasing Coalbed Methane Formation Damage Using Microfoamed Drilling Fluid Stabilized by Silica Nanoparticles

Table 2

Foaming volume and half-life period data of foamed drilling fluid with different formula in presence of nano-SiO₂.

Formula number	Nano-SiO2 (%)	Foaming volume (ml)	Growth rate of foaming volume (%)	Half-life period (min)	Growth rate of foam stability (%)
1#	0	325	0.00	14.07	0.00
	0.05	350	7.69	16.00	13.72
	0.075	350	7.69	18.67	32.69
	0.1	340	4.62	16.17	14.93
	0.125	330	1.54	14.97	6.40
2#	0	255	0.00	93.68	0.00
	0.05	280	9.80	101.07	7.89
	0.075	300	17.65	156.57	67.13
	0.1	280	9.80	139.18	48.57
	0.125	270	5.88	130.50	39.30
3#	0	275	0.00	20.97	0.00
	0.05	305	10.91	29.48	40.58
	0.075	340	23.64	37.50	78.83
	0.1	285	3.64	27.43	30.81
	0.125	300	9.09	26.93	28.42
4#	0	150	0.00	63.13	0.00
	0.05	170	13.33	91.74	45.32
	0.075	235	56.67	200.48	217.57
	0.1	230	53.33	156.90	148.53
	0.125	220	46.67	140.40	122.40