No abstract

No abstract

OOPY%@t lW. sOOiOfY of Petroleum Engineers l%&I&MI&ww&w~5~&aonta!bn at tfre 6Srd Annual Tachnkel CeMarenca and Ex5ibltkm of tha SocIaty of Patroleum Englnaara hold in e, -,. LasmAczIt is well known that for q single-phasefluid flowing beteeen smooth parsllelplates, the pressure drop is proportional to the cube of the aperture septrathg the plates. Some .investig8tors2 vS have looked qt the qffect of surface rougbmesson flow ueing fabricatedsurfaces, inducedfractures, or sawed $urfaces and have found deviation from that law at small aperturee. This paper preeenttr new laboratory data for single-phaseflow throughopen roughnatural fractures.Tvo typea of petroleumresenroirrocks (sandstones and cherts ) were used, each having a differentsurfs.ce rougbness. Flow through both open snd closed fractures is evaluated with apertures ranging between 0.002 to 0.0253 in. A techniquefor maasuringapertures in-situ has been developedwhich avoids backcalculatingaperturesfrom flow data, as other investigatorshave had to do. Fluids with viscositiesof about 1 and 18 cp were used.At large apertures (0.0253 in), compared to the surface roughness, the cubic law ie followed; at smaller aperturee for rough fracturee,deviation is seen. Transitionfrom leminar to turbulentflow is smooth but is dependent on surface roughnese for 9mallerfractureqperturbs. CriticalReynoldsNumber, the ReynoldsNumber where leminar flow enda, ia seen to decrease with decreasing fracture aperture for rough fracturee. Data are correlatedusing plots of frictionfactorversusReynoldsNumber.Many reservoirs are fractured to some degree. These natural fracturesmay have substantial or little contribution to the overallflow characteristics of a --Referencesand iHuetrationsat end of paper. reeervoir, depending on the differencebetween the matrix and fracturepermeabilities end the number of fractures. In reservoirshaving good matrix porosity and permeability,productioncontributedby fractures may be so insignificant that fractureein the~~trix qre undetected. In other fracturedrese=o

The management of waste polylactide (PLA) in various solutions of thermophilic anaerobic digestion (AD) is problematic and often uneconomical. This paper proposes a different approach to the use of PLA in mesophilic AD, used more commonly on the industrial scale, which consists of assigning the function of a microbial carrier to the biopolymer. The study involved the testing of waste wafers and waste wafers and cheese in a co-substrate system, combined with digested sewage sludge. The experiment was conducted on a laboratory scale, in a batch bioreactor mode. They were used as test samples and as samples with the addition of a carrier: WF—control and WFC—control; WF + PLA and WFC + PLA. The main objective of the study was to verify the impact of PLA in the granular (PLAG) and powder (PLAP) forms on the stability and efficiency of the process. The results of the analysis of physicochemical properties of the carriers, including the critical thermal analysis by differential scanning calorimetry (DSC), as well as the amount of cellular biomass of Bacillus amyloliquefaciens obtained in a culture with the addition of the tested PLAG and PLAP, confirmed that PLA can be an effective cell carrier in mesophilic AD. The addition of PLAG produced better results for bacterial proliferation than the addition of powdered PLA. The highest level of dehydrogenase activity was maintained in the WFC + PLAG system. An increase in the volume of the methane produced for the samples digested with the PLA granules carrier was registered in the study. It went up by c.a. 26% for WF, from 356.11 m3 Mg−1 VS (WF—control) to 448.84 m3 Mg−1 VS (WF + PLAG), and for WFC, from 413.46 m3 Mg−1 VS, (WFC—control) to 519.98 m3 Mg−1 VS (WFC + PLAG).

No abstract