Valves for Water Treatment and Environmental Protection Industry

Heyue valves recommended selection sheet in Water Treatment and Environmental Protection Industry

Category

Valve Type

Application Scenario

Specific Locations

Advantages

Key Selection Points / Types

Primary Valves

Butterfly Valve

Primary choice for isolation and regulation of large flow rates at medium to low pressures.

Main water supply/drainage pipes (pump inlet/outlet pipes, water plant process connections); Cooling water systems; Aeration systems; Firefighting systems.

Compact structure, lightweight, low cost, low flow resistance, quick opening/closing. Wafer-type concentric butterfly valves are most common.

Body material: Cast iron, ductile iron, or stainless steel; Liner/seat material is crucial: EPDM for clean water, NBR for sewage or oily media, PTFE/F46 for corrosive media.

Gate Valve

For scenarios requiring full open/close, tight shut-off, and infrequent operation.

Inlet/outlet of water/wastewater plant structures (as isolation valves for maintenance); Pump suction and discharge ports (especially large diameters); Pipe sections requiring straight-through flow with minimal pressure loss.

When fully open, the flow path is completely unobstructed, offering minimal flow resistance and reliable sealing.

Non-rising stem design is more common (saves space). In wastewater treatment, pay attention to stem corrosion protection (stainless steel or epoxy coating).

Ball Valve

For small diameter pipelines requiring quick, reliable shut-off or frequent operation.

Chemical dosing systems (coagulant, disinfectant lines like chlorine, sodium hypochlorite); Instrument air pipes, sampling pipes; Gas/water inlet branch pipes for equipment units.

Excellent sealing performance, low operating torque, quick opening/closing (90-degree rotation).

Prefer full-port ball valves to avoid sedimentation. Use with caution for media containing solid particles.

Check Valve

Prevents media backflow to protect equipment like pumps.

Discharge side of all pumps.

Prevents media backflow, protecting equipment.

Main Types:1. Swing Check Valve: General purpose, wide size range. 2. Dual Plate Wafer Check Valve: Very short face-to-face length, lightweight, low cost, widely used. 3. Silent/Non-Slam Check Valve: Prevents water hammer in high-rise or long-distance water supply. 4. Rubber Flap Check Valve: Commonly used in sewage pipelines, good passage, clog-resistant.

Specialty & Functional Valves

Knife Gate Valve

Handles media containing solids, fibers, slurries, and sludge.

Wastewater treatment plants (primary/secondary sedimentation tank sludge discharge pipes, sludge dewatering feed lines); Industrial wastewater treatment (paper pulp, slurry pipelines).

The gate cuts through fibers and particles like a knife, offers low flow resistance, and is not prone to clogging.

Suitable for solid-containing media; abrasion resistance should be considered.

Diaphragm Valve

For scenarios requiring absolute isolation of valve internals from the media, or for highly corrosive/high-purity media.

Chemical dosing/metering systems (as precision regulating valves); Ultrapure water systems (e.g., electronics industry); Corrosive chemical dosing lines.

Smooth flow path, no dead legs, media contacts only the valve body and diaphragm, good sealing, easy to clean.

Suitable for high-purity or highly corrosive media; diaphragm material must be selected based on the media.

Weir Gate & Flap Gate

Used for flow control or isolation in open channels, tanks, and weirs.

Weir Gate: Flow distribution and effluent control in various process units of WWTPs (e.g., grit chambers, sedimentation tanks). Flap Gate: End of pipeline discharge outlets, prevents backflow of water body.

Suitable for non-piped scenarios like open channels.

Select specifications based on channel dimensions and flow rate.

Air Valve & Pressure Relief Valve

Air Valve: Removes accumulated air, preventing air locks and water hammer. Pressure Relief/Safety Valve: Protects pipelines and equipment from overpressure damage.

Air Valve: Installed at the highest points of water transmission pipelines. Pressure Relief/Safety Valve: Installed on equipment or pipeline sections requiring overpressure protection.

Air Valve: Maintains system efficiency. Pressure Relief Valve: Ensures system safety.

Select based on pipeline pressure, diameter, and media characteristics.

Actuation Method Choice

Electric Actuator

Mainstream choice in the water treatment industry.

Most butterfly, gate, and ball valves requiring automatic control.

Requires only electricity, offers precise control, easily integrated for remote/automated control (with PLC, SCADA systems), suitable for dispersed, remote sites (e.g., pipeline pumping stations).

Select based on required valve torque, control precision, and power supply conditions.

Pneumatic Actuator

Suitable for explosive environments or scenarios requiring fast action.

Applications requiring fast switching (e.g., backwash valves), or specific process units with explosive atmospheres (e.g., sludge digestion, biogas systems).

Fast action speed, simple structure, intrinsically safe and explosion-proof.

Requires an air supply; select based on required action speed, torque, and explosion-proof rating.