We are proud to be the pioneer in the field of waste management in Batticaloa district. We were the first hotels to build a biogas plant to digest most of our kitchen organic waste and some garden waste. The biogas we produce fulfills around 20% of the cooking energy need.

The plant was commissioned in April 2015. The total cost was around LKR 150,000 (US$ 1,000) and has a total capacity of 6 cubic metres. On average it can take around 30-40 kg of organic waste daily.

Building the plant

We started the foundation approximately 2 feet from the ground level so that we can keep the feeding inlet as low as possible to the ground. This way adding organic waste into the biogas plant will require less effort. Unfortunately due to the close proximity to lagoon and the constant threat of flash floods we were unable to build the foundation much lower.

The building quality is maintained to a high standard as the unit should stand extreme pressure from the water it will contain and the gas it produces. We used reinforced concrete for the base and 9 inch brick walls to complete the plant.

Initially to start off the anaerobic process we use cow dung mixed with water.biogas The plant is already filled with water and for the next 2 weeks we will be adding this mixture so that the process can gradually take place. After 2 weeks time you will see biogas being produced which can be used for cooking purposes. after this two weeks we can start adding organic wastes into the system.

To gauge the gas production an improvised manometer is used.

Warning

In the initial stages for around 3-6 weeks the plant will produce a very bad odor which will eventually stop once the system is fully converted into an anaerobic reaction.

What we add into our system

Once the methane (CH4) is produced by breaking the organic material the system outputs a slurry rich in microorganisms. This slurry can be used as an organic manure by diluting it with water (1:6).

Bio Slurry (organic) Fertilizer (Dilute 1:6 in water)

PH N% P ppm K ppm Ca ppm Mg ppm Mn ppm
6.7 3 30 250 280 40 1.5

At Riviera Resort we use this rich organic fertilizer for all our new and mature plants. we also use this to charge our biochar.

Two years after operation...

The unit has been in operation for more than 2 years now. You will clearly see from the video below all the organic waste has been fully digested. The sound of the rod hitting the bottom concrete proving the slurry is completely fluid. This is very useful and their is no hassle of removing any solid waste periodically.

The slurry flows through the overflow outlet and gets collected in a PVC tank. This can be taken out directly to be diluted for direct application or pumped into another holding tank which is filled with can be used to charge the biochar

Biogas expiation video