Automatic Data Gathering and Supervisory Control System For Production and Operation in the North Pembina Cardium Unit No. 1

Abstract

Abstract A supervisory control and data gathering system is installed in the North Pembina Cardium Unit No. 1, which is operated by Socony Mobil Oil of Canada, Ltd. This system provides at one central location, readout of production data, logging of alarm conditions and supervisory control over 35 satellite production stations and two central treating stations, handling a total of 462 producing wells. The production data reported includes well-test oil, water and gas volumes. The supervisory control system provides remote control of all production wells. This system was designed making use of essentially conventional electrical components. This system has been in successful operation for more than 18 months effecting reduced maintenance and operating costs while providing increased speed and accuracy in the gathering and processing of production data. Introduction The Pembina oil field is located approximately 70 miles southwest of Edmonton, Alta., Canada. More than 4,200 wells have been drilled within the defined field limits of nearly 1,000 sq miles. The oil is a light brown crude of 37 deg. API gravity which is produced from the Cardium (Upper Cretaceous) sand at an average depth of 5000 ft. The North Pembina Cardium Unit No. 1, which is located within the Pembina oil field, has a total of 568 production and injection wells. The 462 production wells produce into 35 satellite well-test units. The produced oil from the satellite units is moved through a pipeline gathering system and is processed at two treating plants. A map showing the production-system field layout is given in Fig. 1. The design of this production system has been described in previous publications. The satellite units provide individual well production- test measurements of oil, water and gas volume, and regulate and monitor oil production and testing. The treating plants accept crude-water emulsions from the satellite units, dehydrate and ship the oil, and treat and dispose of the water. Gas is separated and sold from the satellite units and the treating plants. This production system requires that considerable measurement and operating status information be acquired from the satellites and the plants which are distributed over an area of roughly 70 sq miles. In addition, certain control functions must be effected at these locations. For the purpose of both gathering the information and effecting needed control, a centralized data gathering and supervisory control system is provided. This system has been in operation for 18 months and is highly successful. This paper relates the criteria used in the design and describes the functions and the physical construction of this supervisory system; it also examines the actual performance of the system and its economic effect on production operations since it has been placed in operation. Supervisory System Design Criteria It was established during the economic feasibility investigations made in the production facilities for the North Pembina Cardium Unit No. 1, that a supervisory system was required to observe and to control the production operations from a central location. JPT P. 1263ˆ