Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 AGH Drilling, Oil, Gas

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Characteristics of oil based muds and influence on the environment

Jamrozik A., Protasova E., Gonet A., Bilstad T., Żurek R.

AGH Drilling, Oil, Gas

2016

Vol. 33, no. 4

681--691

Oil based muds (OBM) are highly important in well drilling. Water based muds (WBM) and synthetic based muds are not providing sufficient qualities in fulfilling all of the functions of OBM. OBMs ensure more efficient drilling but also disadvantages such as higher initial cost, more stringent pollution controls and reduced effectiveness of some logging tools. Expenses for mud are reaching 10–15% of total well cost. However, high costs are still low compared to expenses for corrective measures in the case of using mud with poor properties, which could lead to drilling disruption as well as excessive time and cost. OBM and cuttings are saturated with toxic compounds and if discharging to sea poses ecological threats. Perhaps the most hazardous oil component for aquatic organisms are low-boiling aromatics, which consist of benzenes and naphthalenes both soluble in water. Additionally, the higher-boiling aromatic fractions are of high environmental interest due to their persistence in sediments, leading to enzyme induction, cellular dysfunctions, genetic alterations, and chronic effects on organisms. There is a difference in volume of generated waste between using water- and oil-based muds. WBM produces 7,000–13,000 bbl of waste per well. Depending on well depth and diameter 1,400–2,800 bbl are drill cuttings. OBM generates mush less waste as the mud is usually recycled and only drill cuttings with volumes of 2,000–8,000 bbl per well need treatment prior discharge. This paper discusses the hazardous effect of toxic compounds in OBM and evaluates the efficiency of different OBM treatment towards zero discharge.

Improved oil production by membranes

Nair R. R., Saltveit K. J., Protasova E., Bilstad T.

AGH Drilling, Oil, Gas

2015

Vol. 32, no. 1

221--232

The objective of this presentation is to show connections of activities leading to improved oil recovery (IOR) when prospecting for oil and gas. Increased wettability of injected water into the reservoirs is caused by specific ions. Technical limitations for production of designer water from seawater by membrane separation are high-lighted. Desirable characteristics of designer water are low NaCl concentrations and high divalent ion concentrations for improving wettability of Crude Oil, Brine and Rock (CBR). Experimental setup incorporated nanofiltration (NF) membranes for ion separation. Retentate from NF contains the main constituents of Designer Water. A property of NF is to retain divalent ions. Performance of the membranes was evaluated in terms of flux and rejection under varying feed compositions, pressures and recovery rates. The research comprised a technical-economical study for salt separation. Results were evaluated in terms of desalination efficiencies and energy requirements. A sensitivity test, spiking Na2SO4 in the feed seawater, showed a decrease in retention of Cl with increasing SO42- concentrations. A reduced permeate flux resulted, however, with increasing Na2SO4 concentrations.