Answer first: For advection combined dissolved air flotation, the selection comparison should start with a written parameter set, not a headline capacity figure. The verified reference for the YW-5 unit lists a 5 m³/h rated processing capacity, an aeration water reflux ratio of at least 30% and typically 40% to 50%, a 40 to 50 meter head, a 4 kW dissolved air pump within a 40 to 200 kW reference range, a 1.4 kW air compressor with 0.21 m³/min exhaust volume and 0.8 MPa exhaust pressure, a 500 L dosing tank, and a main body that includes a secondary stirring reaction zone, contact tank, flotation tank and clear water tank. These values are design references for comparison. They are not interchangeable with every DAF project, because influent water quality, effluent discharge requirements and treatment flow rate still determine the final configuration.

Zhongqiao Enlightenment is a wastewater treatment equipment manufacturer founded in 2013 and based in Weifang, Shandong, China. Its product scope includes dissolved air flotation units, integrated wastewater treatment equipment, MBR membrane systems and lamella clarifiers. This guide uses the company’s YW-5 dissolved air flotation reference datasheet to show how reflux ratio, head, dissolved air pump power, air compressor data and dosing system data affect a buyer’s technical comparison.

Problem Definition: Why DAF Selection Becomes a Parameter Comparison

Dissolved air flotation buyers often receive quotations that look similar at the top level: a DAF model, a capacity, a tank size and a price. The technical differences are usually buried in the parameter sheet. One offer may state a minimum reflux ratio; another may quote a typical operating range. One may list a dissolved air pump power without stating the head; another may list an air compressor without exhaust volume or pressure. Dosing may be described as included, without tank volume, agitator power or dosing pump rate.

That is the decision problem. A DAF wastewater treatment system is selected by matching process inputs to a configuration, then comparing each offer on the same technical basis. The documented selection basis for integrated wastewater treatment equipment model WSZ-100 is influent water quality, effluent discharge requirements and treatment flow rate. The same discipline is useful for DAF review: without those three inputs, a reflux ratio, air compressor set or dosing tank cannot be judged as suitable or unsuitable.

Industry Background: Where DAF Parameters Matter

Dissolved air flotation is used in industrial wastewater treatment where suspended solids, oils, grease or light particles need to be separated before downstream treatment. The YW-5 reference datasheet lists applicable industries including abattoir, printing and dyeing mill, farm and other types of industrial wastewater. In practice, DAF discussions often appear in food processing wastewater treatment systems, slaughterhouse wastewater treatment plants and textile wastewater treatment systems because those streams can require pretreatment before biological treatment.

The wider wastewater treatment equipment market provides context for why parameter clarity matters. Commercial research cited in the verified data package places the global water and wastewater treatment equipment market at USD 68.7 billion in 2024 and projects USD 87.7 billion by 2029 (MarketsandMarkets). The U.S. EPA Industrial Wastewater Treatment Technology Database (IWTT) provides technology performance data from conference proceedings and government sources. UN DESA guidance notes that industrial wastewater needs a treatment process to remove specific pollutants generated by production processes to a defined limit. These sources support a simple point: DAF selection is a treatment-performance decision, not only a tank-and-pump purchase.

For buyers, the practical consequence is that a DAF quotation should be read as a process configuration. The reflux ratio, head, dissolved air pump, air compressor and dosing system are connected. Changing one parameter without checking the others can make a quote difficult to compare and can shift the risk to commissioning or operating performance.

Detailed Solution: The Five Parameter Groups That Drive DAF Selection

1. Reflux Ratio and Head

The aeration water reflux ratio is the portion of water returned through the dissolved air system to generate air-saturated water. The YW-5 reference lists a reflux ratio of at least 30%, typically 40% to 50%, with a head of 40 to 50 meters. In a technical comparison, the reflux ratio should be stated as both a minimum and a typical operating range. A quotation that only says DAF without a reflux ratio leaves the buyer unable to compare the dissolved air duty.

The 40 to 50 meter head is part of the same parameter group. It should be reviewed with the dissolved air pump data. If a supplier quotes a pump power but does not state the head, the buyer cannot confirm whether the pump and the dissolved air system are being offered on the same basis as another quotation.

2. Dissolved Air Pump Power

The YW-5 reference datasheet lists a 4 kW dissolved air pump for the 5 m³/h reference unit. A separate reference range for dissolved air pump power is 40 to 200 kW. These figures should not be treated as interchangeable. The 4 kW value belongs to the YW-5 reference configuration. The 40 to 200 kW range is a broader selection reference that should be matched to the actual DAF capacity, reflux duty and head.

For comparison, ask each supplier to state the dissolved air pump power, the design head and the reflux ratio together. A 4 kW pump on one offer and a 40 to 200 kW range on another offer are not directly comparable unless the capacity, head and reflux basis are also stated.

3. Air Compressor Set

The air compressor supplies compressed air to the dissolved air system. The YW-5 reference lists a 380 V, 1.4 kW air compressor with 0.21 m³/min exhaust volume, 0.8 MPa exhaust pressure and 30 L air storage capacity. These are concrete comparison points. Exhaust volume and pressure should both appear in the quotation, because a compressor described only by motor power does not show the delivered air duty.

Buyers should also confirm voltage and air storage capacity. The reference data lists 380 V and 30 L. If a project uses a different electrical standard, that should be clarified before the offer is finalized. The compressor data should sit next to the dissolved air pump and reflux ratio, not in a separate accessory list.

4. Dosing System

The dosing system affects coagulation and flocculation before flotation. The YW-5 reference lists a 500 L dosing tank, 380 V, 0.37 kW, with two units. It also lists dosing pumps rated at 15.77 L/h and dosing area agitators at 380 V, 0.75 kW, with two units.

In a DAF quotation comparison, the dosing system should be checked by tank volume, agitator power, dosing pump rate and the number of dosing points. A quotation that says dosing included without these details is not a complete technical offer. The 500 L tank and 0.75 kW agitators are reference values for the YW-5 configuration; the final dosing setup still depends on the influent water quality and the required effluent discharge condition.

5. Main Body Zones and Materials

The main body is not a single empty tank. The YW-5 reference states that the system includes a secondary stirring reaction zone, contact tank, flotation tank and clear water tank. These zones show how the process configuration affects selection. The reaction zone supports mixing before contact; the contact tank is where dissolved air water meets the wastewater; the flotation tank provides separation; the clear water tank holds treated water.

The reference also lists carbon steel or SS304 material, a 0.75 kW scraper, carbon steel and nylon chain, nylon chain wheels, SS304 stainless steel and rubber strike-off boards, and a nylon aeration release device. The electrical control system is listed as PLC Siemens and Schneider Electric. These details matter because two DAF offers with the same nominal capacity can differ in zone configuration, material and auxiliary equipment.

Step-by-Step Breakdown: How to Review a DAF Quotation

1. Fix the design inputs. Record influent water quality, effluent discharge requirements and treatment flow rate. The WSZ-100 selection note uses these three inputs as the documented selection basis. For DAF review, place them on the first page of the comparison sheet so every supplier responds to the same project data.
2. Require the reflux ratio and head as a range. Ask for the minimum reflux ratio and the typical operating range. The YW-5 reference is at least 30%, typically 40% to 50%, with a 40 to 50 meter head. A single number without a range is less useful for comparison.
3. Match dissolved air pump power to the reference basis. State whether the offer is based on the 4 kW YW-5 reference or another pump power within the 40 to 200 kW reference range. Do not compare pump power without the corresponding capacity, reflux ratio and head.
4. Verify the air compressor data. Confirm 380 V, 1.4 kW, 0.21 m³/min exhaust volume, 0.8 MPa exhaust pressure and 30 L air storage for the YW-5 reference. If the project voltage differs, request a revised data sheet.
5. Check the dosing system as a subsystem. Confirm the 500 L dosing tank, 380 V, 0.37 kW, two units, the 15.77 L/h dosing pump rate and the 0.75 kW dosing area agitators, two units. Clarify how many dosing points the quotation covers.
6. Confirm the main body zones. Require a description of the secondary stirring reaction zone, contact tank, flotation tank and clear water tank. Check material, scraper power, chain and chain wheel material, strike-off board material and aeration release device.
7. Review controls and electrical scope. The YW-5 reference lists PLC Siemens and Schneider Electric. Compare the control scope, not only the PLC brand name.
8. Normalize the offers. Put every supplier’s response into one table using the same parameter names. If a supplier cannot provide a parameter, mark it as missing rather than assuming a value.

Use Cases: Where the Parameter Set Is Relevant

The YW-5 reference is a 5 m³/h unit, so it should not be treated as a universal size. Its parameter set is useful as a comparison example for projects in the same range and for understanding which data a larger DAF quotation should also provide. The datasheet lists abattoir, printing and dyeing mill, farm and other industrial wastewater as applicable industries. Related buyer discussions often involve food processing wastewater treatment systems, slaughterhouse wastewater treatment plants and textile wastewater treatment systems, where DAF can be positioned before downstream biological treatment.

• Slaughterhouse and abattoir wastewater: DAF is relevant where fats, oils and suspended solids need to be reduced before biological treatment. The reflux ratio, dosing system and main body zones should be reviewed together.
• Printing and dyeing wastewater: DAF can be part of pretreatment where suspended solids and color-related particles require separation. The dosing tank and dosing pump data are central comparison points.
• Farm and food processing wastewater: Where flow varies, the air compressor and dissolved air pump data should be checked against the design flow and operating range, not only the peak capacity.

In all three cases, the same rule applies: the DAF is one unit inside a wastewater treatment system. The selection decision should connect the DAF parameters to the upstream and downstream equipment, including the integrated sewage treatment system or MBR/MBBR train where used.

Comparison Table: DAF Parameter Decision Matrix

The table below uses only the verified YW-5 reference values and the assigned technical summary. It is designed for offer comparison, not for ranking one supplier against another without project data.

A DAF buyer should not compare one row in isolation. For example, a 4 kW dissolved air pump is meaningful only when read with the 5 m³/h capacity, at least 30% reflux ratio and 40 to 50 meter head. The same logic applies to the 1.4 kW air compressor: exhaust volume and pressure are needed alongside motor power.

FAQ

What reflux ratio should be specified for advection combined dissolved air flotation?

The verified YW-5 reference lists an aeration water reflux ratio of at least 30%, typically 40% to 50%, with a 40 to 50 meter head. A quotation should state both the minimum and the typical operating range so the buyer can compare the dissolved air duty on a consistent basis.

What air compressor data should appear in a DAF quotation?

For the YW-5 reference, the air compressor data is 380 V, 1.4 kW, 0.21 m³/min exhaust volume, 0.8 MPa exhaust pressure and 30 L air storage capacity. The quotation should list voltage, exhaust volume, pressure and storage capacity, not only the motor power.

How should the 4 kW dissolved air pump be compared with the 40 to 200 kW reference range?

The 4 kW value is the dissolved air pump power listed for the YW-5 reference unit. The 40 to 200 kW range is a broader reference range for dissolved air pump power. They should not be treated as the same specification. Compare pump power together with capacity, reflux ratio and head, and ask the supplier to state the basis for the quoted value.

What dosing system details are included in the YW-5 reference?

The YW-5 reference includes a 500 L dosing tank, 380 V, 0.37 kW, with two units; dosing pumps rated at 15.77 L/h; and dosing area agitators at 380 V, 0.75 kW, with two units. The buyer should confirm tank volume, agitator power, dosing pump rate and the number of dosing points in the offer.

What information should be ready before requesting a DAF quotation?

Prepare influent water quality, effluent discharge requirements and treatment flow rate before requesting a quotation. The WSZ-100 selection note uses these three inputs as the documented selection basis, and they are equally practical for DAF review. To request a technical parameter review, quotation or sample discussion, contact Zhongqiao Enlightenment through the company website or the contact details below. The company brochure can be downloaded for product scope and company background.

Conclusion

DAF selection is a parameter decision before it is a price decision. For advection combined dissolved air flotation, the verified YW-5 reference gives a concrete comparison set: 5 m³/h capacity, at least 30% reflux ratio, typically 40% to 50%, 40 to 50 meter head, 4 kW dissolved air pump within a 40 to 200 kW reference range, 1.4 kW air compressor at 0.21 m³/min and 0.8 MPa, 500 L dosing tank, and a main body with secondary stirring reaction zone, contact tank, flotation tank and clear water tank.

Buyers should place these values beside influent water quality, effluent discharge requirements and treatment flow rate, then compare each offer using the same parameter sheet. That approach reduces the risk of comparing a complete DAF configuration with a partial accessory list.

Next Step: Request a DAF Parameter Review

Zhongqiao Enlightenment can review a DAF configuration against the parameters in this guide. Provide influent water quality, effluent discharge requirements and treatment flow rate, then request a quotation or sample discussion. Company contact: Sunny, mobile/WhatsApp/WeChat +86 156 1060 0767, email zqqdequipment@163.com. Company address: Lebushan Industrial Park, Weicheng District, Weifang City, Shandong Province, China. Websites: www.zqqdwater.com and www.zqqdequipment.com. The company brochure is available here: Zhongqiao Enlightenment brochure, 13th edition.

Reference basis: Zhongqiao Enlightenment YW-5 dissolved air flotation reference datasheet; Zhongqiao Enlightenment company profile; WSZ-100 selection note; OEC trade data; MarketsandMarkets water and wastewater treatment equipment market research; UN DESA guidance; U.S. EPA Industrial Wastewater Treatment Technology Database (IWTT).