Experiment of Fluid Driven Rotational Device for Scaling Removal Inside the Geothermal Well

The purpose of this study is to design and develop a fluid-driven down-hole scraper including the rotation sensor to remove scaling inside the wellbore (patent pending).The experiments include artificial channel tests, horizontal production pipe tests and downhole casing tests. The study conducts the scraper into the horizontal production pipe in IC-13 and the down-hole casing for the test of removing scaling in IC-19 and IC-21, Chingshui geothermal site. Furthermore, for the purpose of understanding results of test, we install the rotation sensing and photometer to detect the rotating speed of impeller and the production brine of turbidity. The sensor and photometer assist the techanicians in evaluating the working status of the downhole rotational device driven by flowing fluid. The laboratory tests show that the rotating speed of impeller goes up to 60 RPM as the fluid rate of 0.43m/s and the normal force is 0.4N. The horizontal production pipe test show that the thickness of scrape about 2mm as the flow rate is 2.62 ton/hr. The down-hole casing tests show that scraper rotation can achieve 120 rpm while the production rate is around 4.8~4.9 ton/hour. On site tests confirm that the scraper can be rotated fluid-driven via the signal of magnetic sensor and turbidity sampling. This study extended from the laboratory tests to on site test. In this paper, we mainly focus on the down-hole scraper casing test.