Automatic Data Readout Cuts Equipment and Labor Costs In Oklahoma Waterflood Project

Abstract

Abstract Automatic data readout is being utilized at seven LACT batteries in the North Burbank Unit to determine BS AND W, temperature and gravity. This results in a more efficient operation by increasing the accuracy of determining the three required functions for selling crude oil and by reducing operating labor. The paper covers the type of equipment utilized and the operating characteristics of the system. Introduction The North Burbank Unit, a waterflood project, is located in the northwestern portion of Osage County, Okla., Phillips Petroleum Co. is the operator. The unit was started in 1951 and presently has nine LACT systems, two manual tank batteries and 13 water-injection stations. The present average daily production is 24,500 bbl of oil and 175,000 bbl of water. Water is injected into the Burbank sand and recovered through a completely closed system. Fig. 2 is a typical LACT system and water- station installation. A basic dump-tank type system is used for the North Burbank LACT. Vessels comprising a system (see Fig. 2) are the 95-bbl meter tank, the 61-bbl pipeline sump and one 545-bbl surge tank. Four other stock tanks in series furnish the emergency storage for both water and oil. Flow of merchantable oil is from the heater treater to the surge tank, through the transfer pump to the meter tank, into the pipeline sump and then to the pipeline pump-quite conventional for LACT systems throughout the industry. Maximum capacity is approximately 7,000 B/D. This delivery volume depends upon the capacity of the transfer and pipeline pumps. An automatic-data-readout system is used at 7 of the 10 LACT installations. This equipment eliminates the need for storing and analyzing crude-oil samples. BS AND W, temperature and API gravity are measured electronically each time the meter tank fills. Measured values are stored on electrical-impulse counters for readout as required by the Production Dept. to determine daily oil production and by the various pipeline companies to write their weekly run tickets. Typical Fill and Dump Cycle Following is a description of one fill and dump cycle starting with the meter tank empty (see Figs. 1 and 2 -- a block diagram of the data- readout system and an LACT flow sheet, respectively). When the transfer pump starts, oil flows through the BS AND W cell to the meter tank. The BS AND W monitor continuously measures the volume per cent of BS AND W in the stream. This value is digitized by the averager and pulses are stored on a counter. Since this is a rate function (pulses/minute/per cent BS AND W), the time (minutes) required to fill the meter tank is also digitized and accumulated on a counter. When the tank is full, the transfer pump stops and BS AND W data are no longer digitized. However, the monitor continues to analyze the sample of oil in the monitor pump-bypass stream from the surge tank and will shut down the system if excess BS AND W is detected. JPT P. 473^