The Renewable & Low Carbon Energy website for agricultural and rural communities

Biogas plant utilises mixing system to boost yields

Case Studies

A recently opened biogas plant in Taiwan, using livestock manure as a feedstock, is optimising its’ biogas yields by utilising Landia’s digester mixing system.

The Pushige Biomass Energy Centre project, located in Hualiean County, East Taiwan – the first in the country to use livestock manure as a feedstock – is part of a clean-energy development plan from the Yexing Environmental Technology Company.

Six of Landia’s externally mounted GasMix Systems, boasting a verified track record in the enhancement of biogas yields in projects across the globe, are helping to generate approximately 876,000 kilowatt-hours of electricity each year for the Taipower grid, which is equivalent to the electricity capacity of 250 households.

The 18.5kW mixing units (ordered by Fluid Power Co, LTD) are processing over 300 tons of livestock manure wastewater every day, sourced from the breeding area of Sanmin, Yuli Town, home to roughly 10,000 pigs and 700 cows, spread across 8 livestock farms.

The digester mixing system draws thick liquid from the bottom of the 6,000m3 tank where, with the assistance of the Landia Chopper Pump (invented in 1950), solids are chopped to prevent clogging of pipes and nozzles and in this way speed up the digestion process.

Initially the livestock wastewater is injected into the upper half of the digester, while biogas is aspirated from the top of the tank and mixed into the liquid. This approach reduces buoyancy at the surface of the liquid and helps the gas bubbles to continue to mix once the pumps are switched off.

Mark Lo, MD of Fluid Power Co, LTD said:

“The early results already prove conclusively that the Landia digester mixing system is the very best for producing high levels of methane – and quickly. It is also extremely reliable and very easy to maintain”.

In addition to producing biogas and creating a high-quality fertilizer from the residue, the $3million energy centre will also help reduce the amount of nitrogen from livestock wastewater, as well as both the biological and chemical oxygen demand into irrigation channels and the Xiuguluan Creek by almost 110,000 metric tons each year. CO2 emissions will also be reduced by an estimated 3,000 metric tons. The nutrient rich and organic biogas digestate is being applied to the land of local rice farmers, removing the need for chemical fertilisers, and greatly reducing the farmers’ environmental impact.

Related

Latest in Advice & Opportunities