The invention provides a process
system for disposal and recycling of
sewage in oil plants and the corresponding operation method, wherein the process
system comprises a disposal unit for
sewage of superhigh concentration, a disposal unit for
sewage of
high concentration, a disposal unit for sewage of low concentration and a sewage recycling unit. The invention is characterized in that: after treated by an oxidation
tower and a sequencing
bioreactor, the sewage of superhigh concentration is
effluent and incorporated in the sewage of
high concentration; after treated by a separation tank, a floatation tank and a biological aerated filter, one part of the sewage of the
high concentration which comes up to the standards is released, another part is used for
dilution water of the sequencing
bioreactor, and last part is incorporated in the sewage of low concentration; after treated by a separation tank, a floatation tank and a biological aerated filter, one part of the sewage of low concentration is
effluent and used for recycling in a
reclaimed water system, one part is incorporated in the sewage of high concentration, another part is used for
dilution water of the sequencing
bioreactor, and last part which comes up to the standards is released. The process system of the invention realizes respective treatment and water recycling of sewage of high and low concentration in oil plants, can ensure that the
effluent water quality is stable and qualified and the cost of disposal and recycling of sewage is reduced.