Bitumen Emulsion Production Guide: How to Select the Right Plant for Your Road Project

Bitumen Emulsion Production Guide: Process, Equipment, and How to Choose the Right Plant

Bitumen emulsion has become an essential material in modern road construction and maintenance. It is widely used for tack coats, prime coats, surface treatments, fog seals, slurry seals, microsurfacing, and various cold recycling applications.

Compared with conventional hot bitumen applications, many emulsion-based treatments can be carried out at lower temperatures. This helps reduce energy consumption during road maintenance while providing a practical solution for projects that require efficient and flexible paving methods.

However, producing a stable bitumen emulsion is not simply a matter of mixing bitumen with water.

The final quality depends on several factors, including temperature control, emulsifier formulation, dosing accuracy, colloid mill performance, bitumen-to-water ratio, particle size, and process stability.

In this guide, we explain how a bitumen emulsion plant works, which components are required, and how to select the right plant configuration for your road project.

1. How Is Bitumen Emulsion Produced?

Bitumen and water do not naturally mix. To create a stable emulsion, hot bitumen must be dispersed into very small droplets within a water phase containing an emulsifier.

A typical bitumen emulsion production process includes the following steps.

Step 1: Heating the Bitumen

The base bitumen is heated until it reaches a suitable viscosity for pumping and emulsification.

For many formulations, the bitumen temperature is typically around 130°C to 140°C, although the exact value depends on the bitumen grade and the specific emulsion formulation.

Stable heating is important. If the bitumen temperature is too low, viscosity becomes too high for efficient dispersion. If the temperature is excessive, it may increase the risk of binder aging.

For a broader engineering reference on heating, pumping, and storage temperatures for different binder types, see our Bitumen Storage and Pumping Temperature Guide.

Step 2: Preparing the Soap Solution

Water is mixed with an emulsifier and, depending on the formulation, pH regulators and other additives.

The soap solution is normally prepared at a lower temperature than the bitumen, often around 55°C to 70°C.

The formulation can be adjusted to produce different emulsion grades, including rapid-setting, medium-setting, and slow-setting emulsions.

Step 3: Metering Bitumen and Soap Solution

The heated bitumen and the prepared soap solution are then delivered toward the colloid mill.

Accurate control of the bitumen-to-water ratio is critical. Even small changes in dosing can affect residual bitumen content, viscosity, storage stability, and the final performance of the emulsion on site.

For this reason, an industrial bitumen emulsion plant should use reliable pumps, flow-control devices, valves, and temperature monitoring systems.

Step 4: Colloid Milling

The colloid mill is the core component of a bitumen emulsion production plant.

It applies high mechanical shear to break the bitumen into microscopic droplets and disperse them throughout the aqueous phase.

A properly configured production system can typically produce a fine and uniform emulsion with particle sizes in the micron range. For example, Feiteng's QRL Series Bitumen Emulsion Equipment is designed for an emulsion fineness of approximately 1–5 μm.

Consistent particle size distribution is important because it directly influences emulsion stability, storage behavior, and application performance.

Step 5: Cooling and Storage

After passing through the colloid mill, the finished emulsion is transferred to the storage system.

Depending on the plant configuration, a heat exchanger may be used to lower the emulsion temperature while recovering part of the thermal energy for reuse elsewhere in the process.

The finished emulsion should then be stored in a suitable tank equipped for gentle heating and slow agitation. Emulsion is much more temperature-sensitive than conventional penetration bitumen: overheating may cause the emulsion to break, while long periods without agitation can lead to separation.

For projects that require buffer storage between production and truck loading, see the Feiteng vertical emulsified bitumen heating, storage and mixing tank.

2. Main Components of a Bitumen Emulsion Plant

A complete bitumen emulsion production line usually includes several integrated systems.

Bitumen Tank

The bitumen tank stores and maintains the binder at the required process temperature before it enters the emulsion production line.

A reliable heating system and effective thermal insulation are important for maintaining stable viscosity and reducing unnecessary heat loss.

Water Tank

The water tank supplies the water required for preparing the aqueous phase.

Soap Solution Tank

This tank is used to prepare and maintain a homogeneous mixture of water, emulsifier, and additives.

For acidic or alkaline formulations, the tank material and piping system should be compatible with the chemical conditions of the solution.

Dosing and Metering System

Pumps, valves, sensors, and flow-control devices determine how much bitumen and soap solution enter the process.

Accurate dosing is especially important when one plant is required to produce multiple emulsion formulations.

Colloid Mill

The colloid mill provides the high-shear energy required to disperse bitumen into the water phase.

When evaluating a bitumen emulsion plant, buyers should pay attention to:

• rotor and stator material;
• wear resistance;
• achievable particle size;
• continuous operating stability;
• adjustment capability;
• ease of inspection and maintenance.

Heat Exchanger

Some bitumen emulsion plants use a heat exchanger to recover thermal energy from the finished emulsion.

This heat can be reused to warm process water, improving overall thermal efficiency and reducing the amount of external heating required after startup.

Control System

A modern production line may include:

• temperature monitoring;
• pump control;
• speed regulation;
• flow or solid-content monitoring;
• alarm functions;
• automatic production sequences;
• recipe management.

The more consistent and repeatable the required production, the more important the control and automation system becomes.

3. What Affects the Quality of Bitumen Emulsion?

Emulsion quality depends on the complete production system rather than on the colloid mill alone.

Temperature Control

The bitumen must reach a viscosity suitable for pumping and dispersion. At the same time, the soap solution must remain within a stable operating temperature range.

Poor temperature control can directly affect particle formation and emulsion stability.

Bitumen-to-Water Ratio

This ratio has a major influence on the residual bitumen content of the final emulsion.

Unstable metering can result in batch-to-batch variation and inconsistent performance during road application.

Particle Size

Fine and uniform bitumen droplets generally contribute to better emulsion stability.

The Feiteng QRL Series is specified with an emulsion fineness of 1–5 μm, depending on the model, formulation, and production conditions.

Emulsifier Formulation

The type and dosage of emulsifier influence several properties, including:

• emulsion stability;
• ionic charge;
• breaking speed;
• aggregate compatibility;
• storage performance.

The production equipment therefore needs enough flexibility to adapt to different project formulations.

4. Batch or Continuous Bitumen Emulsion Plant: Which One Should You Choose?

There is no single plant configuration that fits every project.

The right choice depends on required capacity, production frequency, formulation changes, storage conditions, and project logistics.

Batch Production

A batch-type plant can be suitable when:

• different formulations are produced frequently;
• daily production volume is moderate;
• flexibility is more important than maximum output;
• recipes need regular adjustment.

This type of system can suit road maintenance departments, municipalities, contractors, and specialized emulsion producers.

Continuous Production

A continuous production line is generally more suitable when:

• daily production demand is high;
• the same formulation is produced for long periods;
• large road projects require stable supply;
• production efficiency is a priority.

Large highway projects and permanent production bases may require higher-capacity systems with a greater level of automation.

5. How to Choose the Right Bitumen Emulsion Plant Capacity

Plant capacity should not be selected only by looking at the maximum rated output.

The buyer should also consider:

• daily emulsion consumption;
• available production hours;
• finished-product storage capacity;
• bitumen supply conditions;
• loading and transportation efficiency;
• expected future production demand.

A reasonable capacity reserve is usually better than operating the plant continuously at its maximum limit.

For reference, Feiteng currently offers the QRL-6 with a rated production range of 6–8 t/h and the QRL-10 with a rated production range of 8–12 t/h. See the complete QRL Series technical parameters for details.

6. Common Applications of Bitumen Emulsion

A bitumen emulsion plant can be used to produce formulations for a wide range of road applications.

Tack Coat

A thin layer of emulsion is sprayed between pavement layers to improve bonding.

Prime Coat

Bitumen emulsion can be used to prepare certain untreated or granular bases before placing the next pavement layer.

Surface Dressing and Chip Seal

Emulsion is sprayed onto the road surface before aggregate is applied to create a protective wearing layer.

Fog Seal

A diluted emulsion can be applied to aging asphalt surfaces to help seal minor surface defects and slow surface deterioration.

Slurry Seal

Slurry seal combines bitumen emulsion, fine aggregate, water, and additives to restore pavement surface condition.

Microsurfacing

Microsurfacing uses specially formulated emulsion systems designed for rapid setting and relatively quick reopening to traffic.

Cold Recycling

Bitumen emulsion may also be used in cold in-place recycling and other pavement rehabilitation processes.

7. What Should You Check Before Buying a Bitumen Emulsion Plant?

Before requesting a quotation, prepare the following project information:

• required production capacity in tons per hour;
• type of emulsion to be produced;
• target residual bitumen content;
• available bitumen grade;
• type of emulsifier;
• local electrical voltage and frequency;
• available heating fuel or heat source;
• required finished-emulsion storage capacity;
• transport and installation requirements;
• required level of automation;
• climate conditions at the project site.

These details allow the equipment manufacturer to configure the pumps, tanks, colloid mill, heating system, piping, and control system more accurately.

8. Feiteng QRL Series Bitumen Emulsion Equipment

The Feiteng QRL Series Bitumen Emulsion Equipment is designed for road contractors, municipal road programs, EPC projects, and road-material producers that require stable emulsion production in an export-ready equipment configuration.

The current QRL range includes:

• QRL-6: 6–8 t/h;
• QRL-10: 8–12 t/h;
• Emulsion fineness: 1–5 μm;
• Content adjustment range: 10%–70%;
• Content control accuracy: approximately 1%.

The system uses integrated bitumen pumping, water heating, emulsifier preparation and dosing, colloid milling, finished-emulsion cooling, and loading processes.

Its high-efficiency heat exchanger is designed to cool the finished emulsion while transferring recovered heat to production water, helping improve process efficiency.

View QRL Series Bitumen Emulsion Equipment →

9. Finished Emulsion Storage Is Part of the Production System

A common mistake is to focus entirely on the emulsion plant while ignoring what happens after production.

Finished bitumen emulsion should not be handled in the same way as conventional hot bitumen. Excessive heat can damage the emulsion, while long periods of static storage can promote separation.

For this reason, projects that produce emulsion ahead of truck loading may benefit from a dedicated finished-product buffer tank with gentle indirect heating and slow agitation.

The Feiteng RLC-18 vertical emulsion finished-product tank is designed specifically for this role, providing storage, agitation, heating, pumping, and metered loading between the production line and downstream trucks or distributors.

10. Frequently Asked Questions

What particle size is suitable for bitumen emulsion?

The required particle size depends on the emulsion formulation and application. Industrial production generally aims for a fine and uniform dispersion. Feiteng QRL Series equipment is specified at approximately 1–5 μm.

What temperature should bitumen be heated to for emulsion production?

For many formulations, bitumen is processed at approximately 130°C to 140°C. However, the correct temperature depends on bitumen grade, viscosity, and the specific emulsion formulation.

For additional temperature references, read our engineering guide to bitumen storage and pumping temperatures.

What capacity bitumen emulsion plant should I choose?

Capacity should be selected according to actual daily demand, available operating hours, storage capacity, project schedule, and expected future production requirements.

A 6–8 t/h system can suit many smaller and medium road-maintenance operations, while higher-demand projects may require an 8–12 t/h system or a customized production solution.

Can one bitumen emulsion plant produce different emulsion grades?

Yes. A properly configured plant can produce different emulsion formulations by adjusting emulsifier formulation, bitumen content, flow rates, temperatures, and operating parameters.

Is the colloid mill the most important part of the plant?

The colloid mill is one of the key components, but stable emulsion quality also depends on dosing accuracy, temperature control, soap preparation, pumping stability, heat exchange, and finished-product storage.

Does bitumen emulsion require a special storage tank?

For projects that need to hold finished emulsion before loading or application, a dedicated tank with gentle heating and slow agitation is preferable to a conventional hot-bitumen storage tank.

See the Feiteng emulsified bitumen storage and mixing tank for an example of this configuration.

Conclusion

Choosing a bitumen emulsion plant should not be based only on price or rated production capacity.

Stable emulsion quality depends on the complete production process, including bitumen preparation, soap-solution formulation, dosing accuracy, colloid mill performance, temperature control, heat exchange, automation, and finished-product storage.

Before selecting a plant, define your required capacity, target emulsion type, bitumen grade, site conditions, utility supply, storage requirements, and transport limitations.

Feiteng can configure a bitumen emulsion production system according to the actual requirements of your road project.

For a technical recommendation, send us:

• project country;
• required capacity;
• target emulsion type;
• bitumen grade;
• available power supply;
• heating conditions;
• required finished-product storage capacity.

Our engineering team can then recommend a suitable production and storage configuration for your application.

Contact Feiteng for a Bitumen Emulsion Plant Recommendation →