Objective
The object of this project is to prepare the test, on-field and for the first time, of a method which will considerably increase the sweeping performance of a reservoir while using nitrogen, a non -miscible, readily available and non expensive gas, combined with foaming agents in small quantity.
After consulting foaming agent manufacturers and reviewing literature, 8 products were selected for the study. These products are either anionic surfactants (mostly sulfonates or sulfates) or amphoteric surfactants used for foam drilling or for manufacturing cleansing agents.
PHASE 1 :
On-site nitrogen generation is feasible at a cost varying from 0. 35 FF/Nm3 for PSA to 0. 47 FF/Nm3 for membranes both for a 5 year project. Buying liquid nitrogen would yield a final cost of 0.
82 FF/Nm3 but access roads were not build to withstand the subsequent heavy truck traffic.
PHASE 2 :
The oil from Coulommes field presents a low oxidation rate.
The risks of auto-ignition or of explosion in the production wells are negligible with less than 10 % of oxygen in the injected fluid.
PHASE 3 :
Preselected foaming agents include sulfates (Neopon LOA/F and Fenopon CD 128), a sulfonate (Sulframin AOS) and amphoteric surfactants (Siponfor S and Foramousse 110). The sulfates and the amphoteric surfactants show a good resistance to aging at reservoir conditions. Adsorption tests indicate that the Fenopon has the lowest adsorption among all products. Foam displacements in porous medium at reservoir conditions and in the presence of oil stress the good performance of the sulfonate and amphoteric surfactants and the poor performance of sulfates. Compatibility tests with formol and anti-emulsion product present in the water used to make foam, indicate that amphoteric surfactants are not affected, while the sulfonate performs slightly worse and sulfates are very affected.
PHASE 4 :
Surface facilities have been designed, measurements to be performed during the test have been listed, a tracer program has been set up. The injection mode will consist in a 60 m3 slug of foaming agent solution followed by a simultaneous injection of gas and foaming solution.
The project is divided into four phases.
Phase 1 : injection facilities.
Two processes are investigated :
- on-site separation of nitrogen from air using molecular sieve or membranes and compression,
- transportation, storage and pumping of liquid nitrogen.
The study takes into account operating constraints.
Phase 2 : Tolerance study of crude oil versus oxygen.
This phase evaluates the risks of letting some oxygen to be injected with nitrogen, especially if on-site separation is chosen.
The oxydation/combustion parameters of the crude oil are measured at two oxygen partial pressures and two temperatures. Compositional thermal simulation of gas injection and crude oxidation are performed.
Phase 3 : Selection of a foaming agent.
Different manufacturers have supplied samples of foaming agents. The ability of these products to foam at 75 deg. C in the presence of 30 g/l of salt and in the presence of oil is tested. Adsorption on rock and aging in the presence of oxygen are studied. The products are compared with one another. The influence of additives present in the field production water are investigated.
Phase 4 : Definition of injection mode.
This phase consists in studying the injection mode of the foaming agent, wether simultaneously with the gas or in several slugs. Surface facilities are reviewed. Recommendations on a measurement and a tracer program are made.
Programme(s)
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
92500 Rueil Malmaison
France