Hydrotesting of Gas Flow Lines

The most important parameter is missing in your question i.e. the "test pressure". It is required question (1).

1) Hydrotesting pump should be of plunger type positive displacement pump. To decide about capacity, use the thumb rule as follows:

"Approximately 10 litre water is to be pushed in 10 cu.m volume to increase the pressure by 10 bar."

Your volume is about 1000 cu.m. Depending on the test pressure, calculate how much water is to be pushed. This will give required pump capacity per hour.

2) Take a centrifugal pump of 60 m head. Capacity you can decide by the time available for filling the required volume. Keep a vent at the highest point in open condition while filling.

3) A small compressor of any type with a delevery pressure of 5 bar is OK. Capacity depends on how fast you want dewatering. Compressed air is to be connected at the vent at the highest point.