CSS-cyclic steam stimulation
Use of Cyclic Steam Stimulation technique for Enhanced Oil Recovery
Cyclic Steam Stimulation(CSS), also known as the steam huff and puff, steam soak, or cyclic steam injection is a process in which a combination of directional and horizontal wells are used to inject high pressure steam into the Clearwater Formation, which warms the bitumen oil viscosities(100-10,000 cp) at reservoir temperature and lowers its viscosity thereby permitting it to flow into the well bore. . Figure 1 shows a typical relationship between the viscosity of a heavy, viscous crude oil and temperature. As can be seen, for certain crude oils, viscosities decrease by orders of magnitude with an increase in temperature of 100–200◦F. This suggests that if the temperature of a crude oil in the reservoir can be raised by 100–200◦F over the normal reservoir temperature, the oil viscosity will be reduced significantly and will flow much more easily to a produce Fig1.Typical Viscosity temperature relationship
Cyclic Steam Stimulation is a three step process as follows(refer to fig2):
1.It begins with the injection of 5000–15,000 bbl of high-quality steam at a temperature of 300-400 degree celcius for a period of days to weeks.
1. 2. The well is then shut in, and the steam is allowed to soak the area around the injection well. This soak period is fairly short, usually from 1 to 5 days. 2. 3. The injection well is then placed on production. The length of the production period is dictated by the oil production rate but can last from several months to a year or more. The cycle is repeated as many times as is economically feasible. The oil production will decrease with each new cycle.
Fig.2
In the paper, the various technical details governing the process like
1. Calculation of radius of heated zone by The Marx and Langenheim Model for
Cyclic Steam Stimulation(CSS), also known as the steam huff and puff, steam soak, or cyclic steam injection is a process in which a combination of directional and horizontal wells are used to inject high pressure steam into the Clearwater Formation, which warms the bitumen oil viscosities(100-10,000 cp) at reservoir temperature and lowers its viscosity thereby permitting it to flow into the well bore. . Figure 1 shows a typical relationship between the viscosity of a heavy, viscous crude oil and temperature. As can be seen, for certain crude oils, viscosities decrease by orders of magnitude with an increase in temperature of 100–200◦F. This suggests that if the temperature of a crude oil in the reservoir can be raised by 100–200◦F over the normal reservoir temperature, the oil viscosity will be reduced significantly and will flow much more easily to a produce Fig1.Typical Viscosity temperature relationship
Cyclic Steam Stimulation is a three step process as follows(refer to fig2):
1.It begins with the injection of 5000–15,000 bbl of high-quality steam at a temperature of 300-400 degree celcius for a period of days to weeks.
1. 2. The well is then shut in, and the steam is allowed to soak the area around the injection well. This soak period is fairly short, usually from 1 to 5 days. 2. 3. The injection well is then placed on production. The length of the production period is dictated by the oil production rate but can last from several months to a year or more. The cycle is repeated as many times as is economically feasible. The oil production will decrease with each new cycle.
Fig.2
In the paper, the various technical details governing the process like
1. Calculation of radius of heated zone by The Marx and Langenheim Model for