The Research And Application Of Wastewater Treatment Technology In Fuxian Oilfield

Water injection is a inportant way to increase oil recovery and efficiency. The treated water about sewage is the key to achieving efficient development of oil fields. A large number of oil-produced sewage is separated by the oil and water. It is a complex system containing suspended substance, oil and dissolved inorganic salts, dissolved gas and dissolved organic matter.then it has the nature of that:harmful to oil reservoir, corrosion to oil-production equipment and pipe line of oil and water transported, scaling in surface pipeline and reservoir. So that oil-production sewage must be purified and decreased its corrosion and scaling property as it is used for flooding water.The 6#,7#,8# united station is a new sewage treatment plant in Zhiluo production of Yanchang oilfield, the produced water from them with low pH, high salinity, high oil and suspended solids(SS) concentration, high iron andlevels of bacteria, and the corrosion scaling is serious, the 6# united station of sewage is a targeted study in this paper, connecting flocculation, oxidation, anti-scaling and corrosion-controlling to the process of wastewater treatment.with the pH adjustment-Chemical oxidation-Flocculation-get water filtration technology, filter out the water treatment agent formulations and mutual compatibility. The experiments show that:when the pH is 7.5, the H2O2 is 20-30mg/L, the CPAM (1200 million) is 2.0-2.5mg/L, the PAC is 80-100mg/L; HDS-08 and AD5-168 is used by alternating adding fungicides, and the amount is 100 mg/L, AD43-3-b inhibitor is 100 mg/L, the KS-1 inhibitor is 30mg/L, the suspended solids, oil content, total iron content, bacteria content, corrosion rates Of the treated effluent are 0.9-1.9mg/L(≤2.0mg/L),2.0-4.3mg/L(≤10mg/L),0.09-0.31mg/L (≤0.5mg/L),0ge/ml,(SRB≤10ge/ml, TGB<100ge/ml),0.0156mm/a (<0.076mm/a). The treated water is stable and good compatibility with the formation water, the damage ratio to rock-permeability is low to 20%. there is no new mineral accrue in the entry and exit of the rock-formation as the purified water is injured to it. At the same time, the 7# and 8# sewage treatment united station are flocculed and put forward the corresponding drug programs.The ratios of oil and water is high about the oil sludge generated 6# united station, the pyrolysis of sludge treatment processes is used to treat oil sludge. Determine the pyrolysis conditions that the pyrolysis temperature of 600℃, heating rate of 15℃/min, the reaction time was 120min, and treated pyrolysis oil, pyrolysis gas and pyrolysis residue are analysised, pyrolysis oil is basically diesel and kerosene-based oil which contains more aromatic hydrocarbons, pyrolysis and gasification are mainly composed by methane, hydrogen, the content methane is about 40%, you can direct combustion heating. the heavy metal content such as Cr, Pb, Ni of pyrolysis residues in acidic and neutral leaching solution does not exceed the hazardous waste standards, the flocculants production named Al2O3 can be obtained from pyrolysis residues by pickling.The experiments show that the pyrolytic treatment sludge can be realized by the"harmless, reduction, resource-oriented" processing.