Blowout Simulations Using Olga-Well-Kill

Simulations of the blowout scenarios give estimates of the oil and gas rates and flowing bottom hole pressures. These simulations also define the starting point for the kill simulations.  The blowout rates can be viewed as a function of:

  1. Reservoir productivity and pressure

  2. Flowing fluid type

  3. Flow path sizes, lengths, restrictions and friction

  4. Exit conditions

The flow path consists of the standard completion and pipe in the hole, with no additional restrictions due to fishes or junk in the hole for these "worst case" scenarios.

Exit conditions are open blowouts to surface with the failed BOP or production tree essentially not giving much restriction to flow. A hole larger than 2" (50 mm) diameter would essentially be similar to a fully open BOP in terms of the blowout rates in this study.

 Blowout rate summary, Alpha

Table -1: Blowout rates Scenario 1

Alpha Well - Scenario 1

Scenario

Flow

Inflow

Reservoir

Reservoir

Flowing

Gas

Gas

No.

Path

From

Temperature

pressure

BHP

rate

rate

in

Sand

Deg C

bar

bar

Mill. m/d

MMscf/d

1a

12¼"-5"dp

2
(1400 mdm)

125.2

461.7

169.5

6.0

212

1a

133/8"-5"dp

3
(635 mdm)

131.0

703.6

172.7

5.6

200

Total 1a

2+3

11.6

412

1b

12¼"

2
(1400 mdm)

125.2

461.7

108.5

6.3

224

1b

133/8"

3
(635 mdm)

131.0

703.6

109.9

5.8

204

Total 1b

2+3

12.1

428

Table -2: Blowout rates Scenario 2

Alpha Well - Scenario 2A and 2B

Scenario

Flow

Inflow

Reservoir

Reservoir

Flowing

Gas

Gas

No.

Path

From

Temperature

Pressure

BHP

Rate

Rate

in

Sand

Deg C

Bar

Bar

Mill. m/d

MMscf/d

2A

 

8½"-
63/4 bha"

8½"-5"dp

97/8"-5"dp

3

131.0

703.6

646.4

1.8

64

2A

6

138.5

832.4

656.5

1.3

47

2A

7

139.9

844.6

666.6

6.4

224

2A

8

140.8

853.4

668.3

0.9

31

Total

Pipe in hole

3,6,7,8

10.4

366

2B

 

 

8½"

97/8"

3

131.0

703.6

421.1

4.6

161

2B

6

138.5

832.4

417.5

2.2

77

2B

7

139.9

844.6

423.2

9.4

330

2B

8

140.8

853.4

424.3

1.4

51

Total

No pipe in hole

3,6,7,8

17.6

619