Filter media support structure loss
Common problems : damaged filter caps, deformed or corroded filter screens, clogged/cracked water distributors.
Causes : Excessive backwashing intensity impacts the filter cap; raw water contains corrosive substances (such as excessive chloride ions); filter screen rusts and ages after long-term operation; impurities clog the gaps in the water distributor.
Symptoms : Sand/filter media particles in the effluent, significant loss of filter media during backwashing, and uneven water flow distribution leading to localized collapse of the filter media layer.
Solution : Check the filter regularly.
Housing and sealing component wear
Common problems : corrosion of the inner wall of the housing, aging and leakage of flange seals, and leakage due to deformation of the manhole door.
Causes : The pH value of the raw water exceeds the standard (too acidic or too alkaline); the seals are aged due to long-term exposure to water pressure and temperature; the flange bolts are not tightened evenly during equipment installation.
Symptoms include : water seepage on the outer wall of the casing, dripping at the flange connection, and stains around the manhole door. In severe cases, this can lead to a drop in equipment pressure.
Solution : Apply an anti-corrosion coating to the casing; replace the rubber gaskets regularly; tighten the flange bolts evenly in a diagonal sequence to avoid excessive local stress.
Pipeline and valve losses
Common problems : scaling/corrosion on the inner wall of pipelines, wear of valve cores, and failure of check valves.
Causes : High hardness of raw water leads to scaling; corrosive media erodes pipelines; frequent opening and closing of valves causes wear on the valve core sealing surface; check valve disc is stuck.
Symptoms include : decreased pipeline flow, internal leakage in valves (water continues to flow out after shutdown), abnormal noise from check valves, and in severe cases, system pressure fluctuations.
Treatment : Regularly acid flush the pipeline to remove scale; replace wear-resistant valve cores (such as ceramic valve cores); disassemble the check valve to clean impurities, and repair or replace the valve disc.
Supporting equipment wear and tear
Common problems : backwash pump impeller wear, motor bearing aging, pressure gauge/turbidity meter inaccuracy.
Causes : Hard particles in the backwash water scour the impeller; long-term high-load operation of the motor; scaling or aging of instrument probes.
Symptoms include : insufficient backwash pump flow, loud motor noise, pressure gauge reading drift, and distorted turbidity meter readings.
Solutions : Install a filter screen at the inlet of the backwash pump; regularly add lubricating oil to the motor bearings; clean the instrument probes and calibrate or replace them periodically.
Regularly perform anti-corrosion and anti-rust maintenance on equipment, especially for components that come into contact with corrosive water.
Control the intensity and frequency of backwashing to avoid excessive impact that could damage components.
Establish a spare parts warehouse for easily damaged parts (filter caps, gaskets, valve cores) and replace aging parts in a timely manner.
