Definition - What does Flowback mean?
Flowback is a water-based solution which flows back to the earth's surface after completing the hydraulic fracturing of the shale gas reserves. This water-based solution consists of chemical additives, mud, clay, dissolved metal ions and TDS (total dissolved solids). The water becomes murky because of the high amount of suspended particles. It is prepared in the first ten days and the remaining solution can be prepared over a period of four weeks. The recovery volume because of flowback is approximately 20-40 percent after injecting into the well for hydraulic fracturing.
Petropedia explains Flowback
When the horizontal drilling and hydraulic fracturing was not much developed, flowback testing was performed in order to clean up the wellbore and its nearby reservoir rock areas by attempting to produce back as much of the treatment fluid as possible. It is also used to get an indication of the amount and type (oil, gas, water) of reservoir fluid that will be produced and at what pressure, if any.
At present, flowback is very much associated with the production of natural gas or shale gas through shale rocks using horizontal drilling and hydraulic fracturing process. It is recovered from the well at the surface when the fluid is used to hydraulically fracture the shale formations. Flowback is considered to be an important step in the drilling operations. After it is recovered from the hydraulic fracturing operation it needs to be properly and safely disposed into the surface along with ground water. This water-based solution needs to be purified before disposal. Some of the equipment used to make it clean are:
- Manual choke manifolds
- Hydraulic choke manifolds
- Plug catchers
- Smug catchers
- Sand separators
- Control trailers