MUSCAT, DEC 16 – The prodigious quantities of bio-waste being generated daily around the Sultanate can feed as many as 10 biogas plants suitable for producing either electricity for local communities or thermal heat for industry. Alternatively, the bio-waste can also be processed to produce biofuel such as biodiesel or simply converted into compost for agriculture, according to a key executive of be’ah, the Sultanate’s waste management flagship. Suad Said al Hosni of Be’ah’s Strategic Development Department said the state-owned entity is currently fine-tuning a number of initiatives that would unlock the economic and commercial potential of recycling the massive volumes of organic and bio-waste currently ending up in landfills across the Sultanate.
“Bio-waste management and bio-energy production are key components of be’ah ‘diversion’ strategy, which seeks to achieve the diversion of around 60 per cent of municipal solid waste away from landfills into recycling and recovery initiatives by the year 2030, rising to 80 per cent by 2040,” Suad told delegates on the second day of the Oman Waste and Environmental Services Conference & Exhibition (OWES) on Thursday. The two-day event was organised by leading events management firm Oman Expo in partnership with be’ah.
Contributing to bio-waste generation in the Sultanate is a mix of green waste, organic waste collected from households, slaughterhouse waste, poultry and livestock waste, household sludge, food waste from restaurants, processing plants and commercial establishments, and fruit and vegetable waste from hypermarkets and the central market. For example, around a third of the estimated 2,100 tonnes of solid waste ending up in the Barka landfill daily is made up of bio-waste, according to Suad.
Based on the volumes of bio-waste being disposed of in landfills across the country, be’ah envisions the potential for at least seven medium to large-scale biogas plants to be established in Muscat, South Al Batinah and Dhofar governorates, where bio-waste generation is the highest, according to the executive. Capacities are expected to range from 1 to 2.5 megawatts (MW).
Barka has been tipped to host the largest of these biogas plants in light of the copious quantities of bio-waste being generated locally. The potential for a further three small-scale biogas plants, of capacities ranging from 0.5 to 1 MW, has been identified in areas with a lower bio-waste footprint, said Suad. As feedstock for the biogas plants, the official explained, the bio-waste will be initially pre-treated in enclosed systems and then subjected to anaerobic digestion in a bio-reactor. Here, the raw material is processed under carefully controlled conditions to achieve the right biogas fuel specs. Material left over from the process can be used as organic fertilizer for agriculture or converted into compost.
Citing examples of biogas use in countries like Austria and Germany, Suad said the environment-friendly fuel is widely used in ‘trigeneration’ systems for generating heating, cooling or electricity. Equally, bio-waste can be used in the production of compost as a local substitute to imports, which presently account for roughly 90 per cent of total compost consumption in the Sultanate. Moreover, local compost can be an environmentally safe alternative to the imported version, which is primarily made up of chemicals or organo-fertiliser.
To showcase the potential for biogas generation from bio-waste, be’ah recently signed a deal with the German University in Oman (GUtech) for the establishment of a pilot plant at its campus in Halban. Set on an area of around 2,000 sq metres, the facility will process between 10 to 50 tonnes per day of organic waste received from the Al Mawaleh Central Market, augmented by supplies from other sources. Electricity output is envisaged at 0.6 MW, which will be used to power some of GUtech’s facilities. Fertiliser and compost generated as a byproduct will be utilised on the campus or marketed locally, she added.