Bitumen Emulsifier: Machines for the Production of Bitumen Emulsion

Emulsification Process (Bitumen in Water)

The production of bitumen emulsions is preferably carried out in colloid mills, which have been built by Probst & Class for decades and have proven themselves in the petrochemical industry.

The emulsification of bitumen in water is achieved by intensive mixing in the presence of an emulsifier. This process can occur either batch-wise (batch process) or continuously (in-line process), with a colloid mill usually providing the required mixing. During the process, the aqueous phase and bitumen pass through the colloid mill, where emulsification occurs.

Adjustable pumps (metering pumps) are used to transfer the aqueous phase and bitumen to the colloid mill.

The aqueous phase contains, besides water, the emulsifier, acid (or base), and, if necessary, a stabiliser, all of which are carefully balanced in quantity. Bitumen is used either pure or mixed with a solvent. The hot emulsion is pumped into a storage tank and kept there for filling and delivery.

The temperature of the emulsion must never reach 100°C during production but should be maintained between 85°C and 95°C. To avoid overheating, the temperature of the bitumen and aqueous phase should be well-coordinated.

Recipe Development in the Laboratory with Colloid Mills from Probst & Class

The application possibilities of bitumen emulsions and the quality demands of customers are high. Therefore, bitumen producers are moving towards developing optimal formulations in the laboratory. Our colloid mill model 60 / O is particularly suitable for this task.

For the development of bitumen formulation, the machine is equipped with a double-jacket housing and double-jacket funnel, as well as a circulation line with a discharge valve.

A circulating thermostat is used for heating and cooling the machine. The working temperature can be selected from the range of 20°C to 250°C. To ensure reproducibility for production conditions, the use of a frequency converter is recommended. For modified bitumen, we provide the corresponding emulsification tools.

Production of Bitumen Emulsion in In-line Operation

In continuously operating plants, preparation tanks for the aqueous and bitumen phases are omitted. All components used are taken directly from storage tanks. The aqueous phase is prepared so that emulsifier, acid and stabiliser are fed into the water stream in predetermined quantities. This is done in such a timely manner that the reaction between the emulsifier and acid occurs before the entire water phase enters the colloid mill.

Water is heated in a heat exchanger. The precise dosing of emulsifier and acid is monitored by a pH electrode installed directly before entering the colloid mill.

Bitumen and solvents are also continuously fed into the colloid mill. The bitumen is stored at the correct temperature, so no further temperature control is required.

Production of Bitumen Emulsion in Batch Operation

In a batch operation, the aqueous phase and bitumen phase are prepared in separate containers and brought to the required temperatures. The fill levels are chosen so that, after combining both phases, an emulsion with the desired bitumen content is achieved. Usually, the containers have level indicators that allow for accurate reading of the outgoing liquid amounts at all times. In this case, the use of metering pumps is unnecessary. Simple pumps can be used instead.

The aqueous phase and bitumen pass through the colloid mill until both storage containers are empty. Since the quantities of bitumen and aqueous phase are precisely prepared, the produced emulsion must meet the content requirements of the bitumen.

Occasionally, bitumen taken from the storage tank is fed directly into the colloid mill. In this case, precise control of the flow rates of bitumen and the aqueous phase is necessary. This is possible through the regulation of metering pumps or with the help of automatic control devices.

Probst & Class as a Supplier to the Petrochemical Industry

Probst & Class mills are "state-of-the-art" machines that have been used in the petrochemical industry for 80 years. Using a PUC, both small outfits and large industrial companies produce bitumen emulsions of consistently highest quality.

The high manufacturing quality of PUC machines typically ensures a service life of several decades. The supply of replacement and spare parts, even for very early models, guarantees a secure investment and low total cost of ownership over the entire life cycle of the machines.