A petrochemical plant produces a large amount of oily wastewater (oil content ≤500 mg/L, suspended solids ≤300 mg/L) during production. Traditional sand filters are prone to clogging and backwashing is frequent, with high operating costs.
Solution
Process design: Use fiber ball filter (polypropylene fiber ball) as the secondary deep filtration unit, connected to the flotation oil removal device in front.
Parameter optimization: filtration speed 15 m/h, backwashing cycle 24 hours (gas-water combined backwashing).
Implementation effect
Oil removal rate: from 500 mg/L of influent water to ≤10 mg/L, suspended solids removal rate >95%.
Operating cost: backwashing frequency reduced by 60%, and agent dosage reduced by 40%.
Maintenance cycle: fiber ball life is up to 8 years, no frequent replacement of filter media is required.
Key points
The high adsorption and oil resistance of fiber balls, combined with the gradient filtration structure, solves the problem of oily wastewater easily adhering to filter media.
