How to inject ozone using a venturi injector?

Working principle

A venturi injector (also called a high-efficiency jet injector) is a gas–liquid mixing device.

Pressurized motive water enters the injector, jets through a nozzle and converts static pressure into high velocity.

The high-speed jet creates vacuum at the suction port, which draws ozone gas (or ozone off-gas / oxygen / air) into the motive flow and mixes it instantly.

The mixture then passes through a divergent diffuser, slows down, recovers part of the static pressure, and discharges.

Two-stage mass transfer

1. Primary injection (venturi): Ozone is sheared into fine micro-bubbles at the throat; mass transfer starts almost simultaneously with suction.

2. Secondary ejection (efficiency-plus nozzle): The mixture is piped to bottom nozzles and ejected at high speed, entraining about 4–5 times its own flow of tank water for further mixing and transfer.

Medium-scale clean-water tests with a GW200 injector (DN50) showed oxygen transfer efficiency above 90% (pure oxygen) and ozone utilization above 99%.

How to connect and operate

Typical connection：

1. Motive loop: circulating pump → venturi injector inlet → mixed-flow outlet → contact tank / secondary nozzles.

2. Gas side: ozone generator outlet → injector suction port (ozone-compatible piping required).

Start / stop sequence for ozone injection

1. Initial state: pump OFF, ozone inlet valve CLOSED.

2. Start the pump and confirm self-suction / air draw is normal.

3. Close the self-suction air valve, then OPEN the ozone inlet valve.

4. To stop: CLOSE the ozone inlet valve first, then shut down the pump and valves per the manual.

Design factors that control transfer

1. Gas-to-water ratio: smaller ratio → higher ozone transfer efficiency (but needs more circulating water / pump power).

2. Water depth: deeper water → higher transfer efficiency (higher civil cost).

3. Injector inlet pressure: higher inlet pressure → higher transfer efficiency (higher pump power).

4. Material: use ozone-resistant stainless steel such as 316 / 316L.

Contact Information

Company Website: https://cd-greenwater.com
Technical Contact Number: 028-85130135
Customer Service Contact Number: 18515915124
Contact Email: jane1984@cd-greenwater.com
Address: No. 191, Section 1, Changcheng Road, Xihanggang, Shuangliu District, Chengdu