Torishima Hong Kong Ltd. (THK) has received an order for a reverse pump axial turbine (IST-PGV900×800, vertical axial-flow) for the Stonecutters Island Sewage Treatment Works managed by the Government of Hong Kong Special Administrative Region, Drainage Services Department (DSD).

Torishima delivered a number of engineered pumps to the Stonecutters Islands Sewage Treatment Works where two pumping stations were constructed under the government leading initiative known as the Strategic Sewage Disposal Scheme Project (SSDS Project) since 1995.

The reverse pump axial turbine will be installed next to the primary sedimentation tank in the plant. It will generate electricity by utilizing the potential head of wastewater from the sedimentation tank to the outfall.

Seawater is used for flushing toilets in Hong Kong, making sewage saline in the area. Primary wastewater used for power generation in this plant will therefore contain seawater too. Torishima has ensured that the water turbine is made of duplex stainless steel in order to protect the turbine from corrosion. 
As for the generator, we have utilized a high efficiency and compact design permanent magnetic synchronous generator. Operators can control flow rate by adjusting speed with variable frequency drive, VFD.

Previously in 2012, Torishima had delivered a reverse pump turbine (vertical, based on double-suction pump) for the Government of Hong Kong Special Administrative Region, Water Supplies Department (WSD). This turbine has exhibited stable performance for power generation to date. This reliability of the previous unit was critical for the approval of the new project.

Harnessing renewal energy has attracted increasing attention in recent years particularly among water related organizations such as WSD and DSD in Hong Kong. The demand for reverse pump turbines will be expected to grow. 
Torishima is continuously contributing to improve economic and environmental conditions in Hong Kong in the years to come.