Study On The Reducing Resistance And Anticorrosion Properties Of The New-type Calcium Base Bentonite Grounding Composite

Major accidents occurred frequently in power system, which makes the resistance and corrosion resistance of grounding grid more and more attention and attention,and it could be better solve the two major problems of resistance reduction and corrosion in the use of resistance reducing agent coated grounding grid, and it has the advantages of simple construction, low cost etc. But at present, the drag reduction effect, corrosion resistance and long-term effect of the resistance reducing agent is not up to the relevant requirements of Electric Power Industry Standard, The paper using calcium base bentonite as matrix, adding conductive particles, corrosion inhibitor and the conductive cement, Developed a low resistivity, good corrosion resistance, good moisture and long novel calcium bentonite composite ground, which provide a better new type of resistance reducing agent of decreasing grounding resistance and anticorrosion performance.This paper focuses on which were preselected in the commonly used metal and carbon conductive particles and the commonly corrosion inhibitor, then the optimum mass fraction of each component in the composite of calcium based bentonite composite which was determined by the orthogonal experiment, the performance of the main indexes in the composite materials of calcium based bentonite which was tested, and the experiment of simulated burying and water retention experiments were carried out.Zn, Fe, Al, graphite, carbon black and carbon fiber were doped with different mass fraction in the calcium base bentonite. The experimental results showed, with the increasing of mass fraction of conductive particles, resistivity decreases and tends to a stable value; conductive particle density, particle size and dispersion and shaft diameter ratio have great influence on the resistivity of the composites.In the calcium base bentonite, sub sodium nitrate, sodium molybdate, sodium silicate, sodium chromate, sodium borate, poly sodium phosphate and sodium phosphate has good anticorrosion performance of Q235?The yield point??s? of carbon structural steel is 235 MPa?; Considering the anticorrosion performance and environmental and economic effects and other factors, and finally determine the sodium molybdate, sodium polyphosphate as a corrosion inhibitor for calcium base bentonite.The results of orthogonal experiment to determine calcium base bentonitecomposite ground the best formula of 2.5% carbon fiber, 9% graphite, 1.5%sodium tripolyphosphate and1.5% sodium molybdate, 40%conductive cement, 45.5% calcium bentonite; The corrosion rate of Q235 is low, and its value is 0.027mm/a, the corrosion product is FeO?OH?, Fe₂?CO₃??OH?, Ca_2.8Fe_8.7Al_1.2Si_0.8?OH?, Fe₂O₃, Fe₃O₄;Water retention tests showed that Water content has little influence on the water retaining property of the composite, but the temperature has a great influence on the water retention; its main indexes meet the requirements of resistance reducing agent in Electric Power Industry Standard.