Well pattern

MesoScale Discovery (MSD) succeeded in introducing product with a similar technology approach based upon ruthenium redox-mediated electrochemical detection (Figure 2.14). MSD is a joint venture of its parent company, MesoScale, and IGEN, a company that pioneered much of fhe work on electrochemical detechon based on the ruthenium redox system. MSD s Multi-Spot plates contain antibodies immobilized on multiple working electrode pads within each well, allowing each spot within the well to serve as an individual assay. Multiplexed cytokine immxmoassays can be performed in 96-well (4,7, or 10 spots per well) patterns with detection limits of 1 to 10 pg/mL and a linear dynamic range up to 3,000 pg/mL. Both 24-and 384-well electrode systems are available. 

Figure 2. Injection, recovery, and monitoring well pattern for an in situ uranium mine ...

Figure 1. Well pattern for the Siggins Field, Illinois, foam...

Figure 2. Well patterns for the CO2 WAG and subsequent surfactant-based CO2 mobility control test at Rock Creek,...

Fignre 8-24. Immunoelectrophoresis mode of operation (B) and Ouchterlony plate well pattern (A). 

Four typical well patterns for contaminant plume containment are described in Ref. 16. The first is a pair of injection-production wells. The second is a line of downgradient pumping wells. The third is a pattern of injection-production wells around the boundary of a plume. The fourth, the double-cell system, uses an inner cell and outer recirculation cell, with four cells along a line bisecting the plume in the direction of flow. Two other methods of plume containment are bio filters and a funnel-and-gate system, which are described in the in bioremediation section. 

A field test was condncted in the well 1-14 pattern in the eastern block of the Gndao field (Wang et al., 2005). The test formation was Ng3-4, and the formation thickness was 13 m. The clay content was 11.8%. In this test, the air permeability was 250 to 3165 md, with an average 1782 md, and the porosity was 30 to 32%. The initial reservoir temperature was 71°C. Before the test, the temperature was 64°C. The oil viscosity at reservoir conditions was 50 to 150 mPa s, and the formation TDS was 3850 mg/L. In the test well pattern, there were 1 injector, Dl-14, and 11 producers around the injector. In April 2004, infill drilling and conformance control were conducted. The water cut decreased only 2%. By January 2005, the water cut reached 96%. 

Before inverse emulsion was injected, the field went through primary depletion, waterflooding, polymer flooding, and post-polymer waterflooding. By July 2004, the water cut in the test area was 90.64%, with a recovery factor of 50.1 %. With 1 injector, Well 21-4, and 5 producers, the injection of inverse emulsion was started in December 2004 at one injection well pattern. The injection program was 10 m polymer solution of 8000 mg/L concentration, 15 m inversion emulsion with 6000 mg/L polymer, and 1167 mg/L phase inversion agent, followed by chase water drive. Four producers out of 5 wells responded to the injection in this test. The injection pressure increased from 7.5 to 9.5 MPa, the water cut reduced from 92.5 to 91.4%, the oil rate increased from 31.9 to 44 fid, and the liquid rate increased from 423.1 to 513.2 fid for the well pattern (Lei et al., 2006). 

The first pilot test in Daqing was started on August 30, 1972, and ended on September 24 in the same year, a total of 26 days. This test was conducted in the Sall7+8 layer. One inverted four-spot pattern was used with the injector, Well 501, in the center. Thus, it was called the Well 501 pattern. The distance between the injector and a producer was 75 m. The formation thickness was 5.2 m, and the permeability was 631 md. The reservoir temperature was 45°C. A 0.163 PV of polymer solution was injected having a concentration from 1000 to 1800 mg/L. The three producers started to respond after 12 days of polymer injection. The water cut at one producer (Well 503) was reduced from 99 to 60.4%, and the well pattern incremental oil recovery was about 5%. The well injection pressure increased, and the liquid production rate was reduced significantly. In this first pilot test, low molecular weight polymer (3 to 5 million Daltons) was used (Liu, 1995 Yang et al., 1996). 

Most of polymer floods in Daqing were conducted in oil zones. There are a significant amount of reserves in transition zones. In 1995, the Sabei transition zone was selected for a polymer flooding pilot test. The target formation was PI1.4. The basic reservoir, fluid, and well data are shown in Table 5.24 (Niu et al., 2006). The well pattern was irregular four-spot. 

The criteria to select the well pattern were (1) the pattern had higher residual oil saturation zones, (2) the pattern location was away from the gas cap or water zones, and (3) existing wells could be used to reduce or eliminate drilling costs. 

Based on the preceding criteria, the selected central well pattern included three injectors (X6, XJ06, XG2) and one observation (production) well (X7). The well spacing (interwell distance) was 160 to 190 m. The four peripheral observation (production) wells, which included XI9, X34, XI, and X47, were well connected. The central pilot area covered 0.037 km with a thickness of 7.4 m. The rock had 6.3% carbonate content and 2.5% clay content. 

FIGURE 13.42 Well patterns in the ASP pilot test at Xing-er-xi (X2-X). 

After 0.097 PV ASP injection, the response was observed at Well X-2-1-22 (marked 22 in the well patterns). From the 9 producers, the oil rate increased from 24 to 134 t/d, and the water cut decreased from 98 to 80.2%. However, Well X-2-2-S1 (SI in the well patterns) stopped pumping after 0.3678 PV... 

In a large-scale ASP application, the production performance and ASP responses from different layers or wells are quite different owing to the vertical and areal heterogeneities. This phenomenon is more obvious in this large-scale application compared with other single-well pattern pilots or small-scale pilots. 

O Producer Injector Observation well FIGURE 13.51 Well patterns in the pilot area. 

FIGURE 13.55 Well patterns in the Karamay pilot area. 

The ASP pilot test described in this section was conducted in the Honggang field in Jilin Province, China. Three well patterns were used in this pilot test Well 7-3, Well 8-4, and Well 125. Figure 13.59 shows the schematic for the... 

Wang, D.-C., Yang, T.-R., Du, T.-R, Fang, B.-F., Yang, C.-Z., 1999a. Micellar/polymer flooding pilot test in the HI84 well pattern in the Laojunmiao field. Petroleum Exploration and Development 26 (1), 47-49. 

Fig. 27 Well pattern and movement of heat flows in block n. 1-5-same as in Fig. 26 6- contours of heat flows.

On the I and II experimental sections (see Fig. 79), the in situ combustion is carried on the "dry" method. A five-point well pattern is used, with the air injection well at the center. The "direct flow" variant of in situ combustion is employed. Observation wells are drilled between the injection well and the producing wells in order to monitor the process at the intervening distances. 

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