Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Thermal transfer performance of downhole electric heaters for in-situ pyrolysis in tar-rich coal

Tang Ying, Xiao Li, Yang Fan, Wu Xiaodan, Su Zhan, Zhang Yue, Jiang Shixin, Yang Peng

Bulletin of the Polish Academy of Sciences. Technical Sciences

2025

Vol. 73, nr 3

art. no. e153839

The paper investigates the performance of a large-size helical baffle heater in an in-situ operation using a numerical simulation method. The study reveals that the fluid in the shell retains a spiral flow, and the output flow velocity is higher than in the surrounding area. However, the pitch design is big, resulting in a low-velocity flow zone on the backwind side. At 100 kW and 500 m3 /h, the fluid flow is turbulent. At 50 kW and 200 m3 /h, the fluid remains laminar. As the flow rate rises, the pressure of tar-rich coal formation grows dramatically. The wall temperature exhibits a spiral plunger at the inlet, but the bottom temperature is symmetrically distributed. Under low power and flow, Reynolds number change has a greater impact on the combination of Nusselt and Prandtl numbers. The wellbore experiences higher thermal loads during downhole heating, dramatically increasing the possibility of thermal damage. An increase in the heater shell length improves the total heat transfer performance. Conventional heaters often only heat the bottom formation. Therefore, while optimizing the construction, it is vital to ensure that the weight of the heater itself does not exceed the tensile strength of the cable and consider shifting down the perforation outlet or lowering the outlet.

Preparation of efficient hydrochloric acid corrosion inhibitor from natural grease

Luo Yi, Xu Zhongying, Cao Xuewen, Wang Yefei, Li Shanjian, Chen Gang, Tang Ying

Polish Journal of Chemical Technology

2024

Vol. 26, nr 2

77--85

To alleviate the metal corrosion problem caused by incomplete acid discharge during pickling or acidification, a corrosion inhibitor, long chain fatty hydrazides (LCFH), with a significant corrosion inhibition effect was synthesized from natural grease. The corrosion inhibition and adsorption properties of LCFH on carbon steel in 1 M HCl solution were studied by static sample weight loss test, electrochemical impedance spectroscopy, and potentiodynamic polarization curve. The results showed that LCFH exhibits excellent corrosion inhibition performance in HCl solution. The inhibition efficiency increases with the increase of inhibitor concentration. When the concentration of LCFH is 40 mg/L, the inhibition efficiency can reach 97.9%. The potentiodynamic polarization curve shows that LCFH is a corrosion inhibitor that mainly inhibits the cathodic reaction. The corrosion inhibitor is spontaneously adsorbed on the surface of low-carbon steel in physical form, which conforms to the Langmuir isothermal adsorption model.