Environmental-related technologies and process solutions have become increasingly important for the Chinese market.

Consequently, and to enable our Chinese customers and prospects to benefit at best from our specific and unique experience in the environmental and recycling fields, we decided to set up in the year 2020 a company that is exclusively focusing on and dealing with these matters: the Shanghai VORTEX entity.

This major step did already pay off in several ways, with a record order book level reached in 2022! One of the main achievements and significant milestones reached refers to the signing of the supply on a turnkey basis of a treatment plant for the valorizing of sewage sludge from dredging pipelines.

The customer – a local state-owned enterprise that is focusing on the environmental infrastructure business – awarded Shanghai VORTEX to build a StaReSa model, with a capacity of more than 3.0tph input material. The project comprises the full engineering design work, the delivery of the equipment as well as the installation and commissioning on site. The commissioning and final start-up are planned to take place in Q3/2023.

The client has already owned several sewage plants and waste incineration plants in China.

With this game-changer investment, which is the first sewage sludge treatment station in Foshan city, the customer positions himself as a provider of superior process efficiency, capable of offering his customers a higher disposal overall performance. As a matter of fact, the recycling products such as sand and gravel will be reused in the municipal infrastructure projects handled by the client. In this way, the final aim of reaching a complete circular economy is moving a step closer!

Process flow concept

With the help of a screw conveyor, the material starts its process in the specially designed high-performance washing drum, type AKA-DRUM where it is thoroughly suspended and fully de-agglomerated. Via the screen basket installed at its end, the material is separated at 30 mm. The particles >30 mm are transported for stockpiling.

The material flow < 30mm is fed to a wet classifying screen, with a cut size at 3mm. The material > 3mm, so-called gravel fraction, is fed to the densimetric classifier, type AKA-JIG for separation of the coarse organic fraction. The following installed double-deck dewatering screen ensures an optimum dewatering of the humidity content in the organic and gravel fractions (3 – 30 mm).

The finer fraction, sand < 3mm, is directed to a hydrocyclone type AKA-VORTEX, followed by high-performance attrition cells type AKA-TRIT, where it undertakes a mechanical surface treatment. Afterwards, an additional hydrocyclone AKA-VORTEX carries out the liquid-solid separation, which will release a deslimed sand (< 3mm) from the wastewater flow. The deslimed sand is then fed to gravity separation system type AKA-SPIN. This process step ensures the separation of the light, organic matter from the heavy, mineral portion (sand). The organics coming out of the AKA-SPIN are dewatered in a bow screen, while the clean sand fraction <3 mm is dewatered on a standard dewatering screen and stockpiled.

In order to optimize the overall investment level and footprint, the management of the process water, so-called grey water, is integrated into the sewage plant located nearby, hence allowing a performing treatment of the wastewater flow.

After the important and critical steps of supervision for the plant set-up and commissioning will be fulfilled, we are very confident that this StaReSa plant will constitute a demo-project and excellent showroom platform for AKW Equipment + Process Design unique process skills and equipment technologies. Accordingly, it is expected that further visitor and business investors will be attracted thereafter, to continue to fuel our growth in the southern China region.