“Sticky Scale” had been a great obstacle in producing gas at our “Dissolved in water type” gas field. However, it has recently been solved by injecting polyphosphates with concentration of 3 to 4 ppm into wells. The author has written on the field test as follows:
1. The properties of EDTA and polyphosphates.
2. The results of tests with EDTA and polyphosphates.
3. The outline of tests.
