Laboratoryjne studium porównawcze oerodków chemicznych stosowanych w zabiegach ograniczania dop³ywu wody do odwiertów gazowych WprowadzenieJednym z problemów techniczno-ekonomicznych podczas eksploatacji z³ó¿ wêglowo-dorów jest wysoka produkcja wody z odwiertów ropnych lub gazowych. Ma to decyduj¹cy wp³yw na ekonomikê procesu wydobycia. Szacuje siê, ¿e produkcja wody z odwiertów ropnych i gazowych ka¿dego roku kosztuje przemys³ naftowy ponad 45 miliardów dolarów. Kwota ta zawiera koszt wydobycia wody na powierzchniê oraz jej utylizacji lub ponownego zat³oczenia do z³o¿a, jak równie¿ wszystkich instalacji naziemnych, niezbêdnych podczas wydobywania wody z³o¿owej z odwiertów produkuj¹cych wêglowodory, oraz koszty zwi¹-zane ze staraniami, by wszystkie niezbêdne procesy nie wp³ywa³y negatywnie na oerodowisko naturalne (Curtice i Dalrymple 2004). Niniejsza publikacja jest kontynuacj¹ prac prowadzonych w Instytucie Nafty i Gazu w Krakowie, zwi¹zanych z modyfikacj¹ przepuszczalnooeci ska³ kolektorskich za pomoc¹ bio¿eli (Falkowicz i in. 2009) oraz dostêpnych na rynku polimerów i mikro¿eli wytypowanych do selektywnego odcinania dop³ywu wody z³o¿owej do odwiertów gazowych i ropnych (Falkowicz i in. 2011). W oewietle uzyskanych wyników badañ laboratoryjnych, celowa jest odpowiedŸ na pytanie: "czy te wymienione zabiegi, znane z literatury angielskiej pod nazw¹ RPM (Relative Permeability Modification),

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractConventional drilling fluids usually contain various polymers, which are the main cause of formation damage. A biological method, which could efficiently reduce this type of damage, was developed. Several halotolerant and thermotolerant microorganisms were isolated and their ability to degrade polymers was tested. Specifically formulated bacterial package proved to be very effective in minimizing starch, xanthan and cellulose-based skin damage when added to drilling mud. The result of experiments showed the usefulness of using the microorganisms for the degradation of polymers and for removal of mud from the pore space. It had been demonstrated that bacterial strains are particularly fitted for degradation of polymers and mud filtrate cake.

No abstract

This article presents a new analytical procedure for pre-selecting gas wells for water shut-off treatments based on available at hand results of an analysis of integrated geological, reservoir and exploitation data. Attention was paid to assess the possibility of the appearance of cross flows between layers in the near wellbore zone. Their appearance always eliminated the well as a candidate for the treatment. The basis for assessing the possibility of the emergence of cross flows was based on the assessment of the presence or absence of impermeable barriers (e.g., shales or anhydrite) in intervals, completed by perforation. For this assessment, well logging data were used, which were carried out in different years with the use of various types of probes. Based on modified quantitative and qualitative interpretation techniques, permeable and impermeable layers were separated in the analysed borehole sections. In some cases, in the absence of other data, well logs are the only source of information from which a vertical profile of horizontal permeability can be made. The article describes the verification process carried out for the eight wells situated in the area of the Carpathian Foredeep, which have been preselected by the operator. As part of this procedure, the available geological, reservoir and exploitation data were used, and a preliminary assessment of the possibility of implementing the obtained results into other wells and gas fields in the area of the Carpathian Foredeep was carried out. On the basis of the well ranking, two out of the eight analysed wells were recommended as candidates for water shut-off treatment.

No abstract