Nepal's largest hospital replaced its incinerator with a biodigester fed on placentas

In 2014 the Nepali non-profit HECAF360 approached Tribhuvan University Teaching Hospital, the country's largest at 700 beds, about its incinerator. BBC reporter Gabriella Jozwiak describes a diesel-fuelled single-chamber unit with no pollution control, whose smoke drifted into paediatric and neonatal wards. Staff had coughs, headaches and rashes but had not linked them to the furnace. Placentas were hard to burn because they are mostly water, so staff added paper and plastic as fuel, including PVC items that release dioxins.

HECAF360's engineer Mahesh Nakarmi had already built an underground food-waste biodigester at Bir Hospital in 2011, drawing on Nepal's long culture of household biogas. Because later hospitals also had maternity wards, he worked with Ruth Stringer of Health Care Without Harm and Dutch engineer Marijn Zandee to modify the design for placentas too. The key change was a second chamber and a longer residence time, about 70 days against 150 to 180 for cow-dung plants.

At Tribhuvan, pathological waste and some food go into the first chamber and the rest of the food waste into the second. Cow dung seeds the bacteria, and the methane is piped to a stove in the staff room. The article says it produces 1.5 cubic metres a day, equal to five LPG cylinders a month, and the design replaced some of the LPG the hospital bought.

Placentas are mostly water, so they burn badly and pushed staff to add plastics as fuel.

Nepal already had decades of household biogas know-how, so the technology was familiar.

Digesting raw hospital waste needs a longer residence time, hence the second chamber and roughly 70 days.

The gas gives the hospital a visible payback by displacing LPG it used to buy.

Adapt a technology the local culture already trusts, like household biogas, to a new waste stream, instead of importing a higher-spec version of the failing process.

The TUTH digester cost about 3.5 million Nepali rupees (almost 20,000 pounds), funded by hospital and government money with HECAF360 support, and the team installed three more at other hospitals. A 2019 assessment found only 36 percent of the expected organic waste was being fed in, because some wards were not connected and kitchen staff sold food scraps as animal feed. It estimated 4.6 tonnes of CO2 avoided in 2019. An independent biogas expert said a larger digester and a heating step would speed up pathogen removal.