Gates Foundation awards grants for 26 sanitation technology projects

A reusable self-decontaminating sanitary napkin, a children’s latrine training mat and a latrine using urine to flush instead of water are among 26 sanitation technology projects that have been awarded Gates Foundation grants. The topics of the wining projects range from hygiene, to household  latrines, ecological sanitation, and wastewater/sludge treatment and reuse for fertiliser and energy.

On 28 April 2011, the Gates Foundation announced that 88 new global health projects received grants, each worth US$ 100,000, in the 6th round of the Grand Challenges Explorations initiative. Out of these 88 projects, there were 26 winners in the category “Create the Next Generation of Sanitation Technologies”. See the full list of 26 sanitation awards. Projects with demonstrated success in their initial phase of research have the opportunity to receive Phase II funding of up to US$ 1 million.

There is another opportunity to submit proposals for sanitation technology grants in round 7 of the Grand Challenges Explorations (deadline 19 May 2011).

Sludge use: ‘Poo-powered’ car seen on the streets of Bristol, UK

A “poo-powered” VW Beetle has taken to the streets of Bristol in an attempt to encourage sustainable motoring.

Photo: Geneco

The Bio-Bug runs on processed methane gas (biomethane) generated as part of the raw sewage treatment process.

Wessex Water engineers estimate the yearly waste from 70 average households would generate enough gas to run the car for 10,000 miles (16,100km).

Despite being powered by fuel created from sewage, the car does not smell unpleasant.

“It performs like a normal car – you wouldn’t know it was powered by biogas,” a company spokesman said.

‘Surplus gas’

To use biogas as vehicle fuel without affecting vehicle performance or reliability the gas needs to be treated to remove the carbon dioxide content.

GENeco, part of Wessex Water, imported specialist “cleaning” equipment to treat the raw methane generated at the sewage treatment works in Avonmouth.

Countries including India and China use compressed natural gas (CNG) to power vehicles and a number of companies in the UK are now using CNG mainly to fuel buses and commercial vehicles. In Sweden, more than 11,500 vehicles already run on biomethane produced from sewage plants.

But using biogas from sewage sludge is yet to take off in the UK despite a significant amount being produced everyday at sewage plants around the country.

The spokesman added: Our site has been producing biogas for many years which we use to generate electricity to power the site and export to the National Grid.

“With the surplus gas we had available we wanted to put it to good use in a sustainable and efficient way.

“We decided to power a vehicle on the gas offering a sustainable alternative to using fossil fuels which we so heavily rely on in the UK.”

Read more about the Bio-Bug on the Geneco web site.

See also: Bio-methane fuelled vehicles – John Baldwin CNG Services, 2008

Source: BBC, 05 Aug 2010

Eco-home: a model for water and sanitation self-reliance in Kathmandu

A resident of Kathmandu has adopted ecological solutions to cope with the city’s persistent water shortage and power cuts.

Report of a visit to Dr. Shrestha’s Eco-home on 14 March 2010.

Dr. Roshan Raj Shrestha in his Eco-home. Photo: C. Dietvorst

Dr. Roshan Raj Shrestha built his Eco-home in November 2002. The two and a half story building is neither connected to the city water supply nor to the sewerage network. It uses several kinds of water conservation methods including rainwater harvesting, greywater recycling, ecological sanitation, Solar Water Disinfection (SODIS) and organic waste composting. Dr. Shrestha says he was able to recover the extra investment of US$ 1,000 for his water conservations systems within three years.

The Eco-home has helped Dr. Shrestha cope with Kathmandu’s severe water crisis. The public water supply can only meet half of the actual demand and the city’s Bagmati river is turning into an open sewer. The ground water level is decreasing by 2.5 metres a year due to over extraction. The mega Melamchi Water Supply Project, started in 1998 to tackle Kathmandu’s water crisis, has been plagued by delays.

Rainwater catchment terrace and tanks. Photo: C. Dietvorst

With an average annual precipitation of 1,600 mm in the Kathmandu Valley, Dr. Shrestha found that rainwater would provide with enough water for his family of five. Rainwater is collected on two roof terraces and stored in a 9,000 litre underground tank. Excess rainwater is diverted into a dug well, which acts as an intermittent tank that can store nearly 10,000 litres and also supports shallow groundwater recharge. SODIS is used to treat rainwater for drinking water, while water from the dug well is pretreated first in a biosand filter.

Residents constructing new houses in Kathmandu now get a 10% tax rebate on their building permit fee if they include a rainwater harvesting system in their design. The rebate can reach 30% in other municipalities in Nepal, says Prakash Amatya, the Executive Director of NGO Forum.

No water goes wasted in the Eco-home. Dr. Shrestha has installed a urine diversion dry toilet in his master bedroom. Urine and composted feces are used as garden fertilizer. A small reed bed treatment system is used to recycle grey water for garden watering, washing the car and for an extra flush toilet.

Solar panel. Photo: C. Dietvorst

The latest addition to the Eco-home is a 100-Watt Solar House System (SHS), installed in 2009. The solar panels provide enough energy to light the lamps in the house. Costing US$ 1,000, the system is only affordable for middle-class families, Shrestha admits, but it has proved its worth now that power cuts of up to 12 hours a day have become standard in Kathmandu.

Dr. Shrestha is proud of his model Eco-home. He is happy to give visitors and groups of students a tour. He finds that people readily accept the concept of rainwater harvesting and greywater recycling. They are not so keen about ecological sanitation though, because of the socio-cultural barriers associated with feces.

Dr. Roshan Raj Shrestha is Chief Technical Advisor, South-Asia Region for the UN-HABITAT Water for Asian Cities Programme

Sources used:

• Eco-home for sustainable living, Himalayan Times / UrbWatSan Nepal, 19 June 2009
• Eco-home for sustainable water management : a case study in Kathmandu, Nepal. Ministry of Physical Planning and Works / UN-HABITAT. October 2008 (brochure)
• Shrestha, R.R. (2007). Sustainable water management : a case study in Kathmandu. Presentation at Ecosan – Fortaleza 2007

SODIS water bottle. Photo: C. Dietvorst

Reed Bed Treatment System for greywater recycling. Photo: C. Dietvorst

Urine diversion dry toilet. Photo: C. Dietvorst

Biosand filter. Photo: C. Dietvorst

Novel membrane bioreactor (MBR) coupled with a nonwoven fabric filter for household wastewater treatment

Xianghao Ren … [et al.] (2010). Novel membrane bioreactor (MBR) coupled with a nonwoven fabric filter for household wastewater treatment. Water research ; vol., 44, no. 3 ; p. 751-760. DOI: 10.1016/j.watres.2009.10.013.

Abstract:

Conventional and modified membrane bioreactors (MBRs) are increasingly used in small-scale wastewater treatment. However, their widespread applications are hindered by their relatively high cost and operational complexity. In this study, we investigate a new concept of wastewater treatment using a nonwoven fabric filter bag (NFFB) as the membrane bioreactor. Activated sludge is charged in the nonwoven fabric filter bag and membrane filtration via the fabric is achieved under gravity flow without a suction pump. This study found that the biofilm layer formed inside the NFFB achieved 10 mg/L of suspended solids in the permeate within 20 min of initial operation. The dynamic biofilter layer showed good filterability and the specific membrane resistance consisted of 0.3-1.9 x 1012 m/kg. Due to the low F/M ratio (0.04-0.10 kg BOD5/m3/d) and the resultant low sludge yield, the reactor was operated without forming excess sludge. Although the reactor provided aerobic conditions, denitrification occurred in the biofilm layer to recover the alkalinity, thereby eliminating the need to supplement the alkalinity. This study indicates that the NFFB system provides a high potential of effective wastewater treatment with simple operation at reduced cost, and hence offer an attractive solution for widespread use in rural and sparsely populated areas.

Keywords: Nonwoven fabric filter bag; Gravity filtration; Self-alkali supplement; Membrane bioreactor; Wastewater treatment

Waste Water Treatment Plant Mud Used As ‘green’ Fuel

Scientists have shown that using mud from waste water treatment plants as a partial alternative fuel can enable cement factories to reduce their CO2 emissions and comply with the Kyoto Protocol, as well as posing no risk to human health and being profitable. These are the results of an environmental impact assessment.

Dependency on oil and coal could be coming to an end. Researchers from the Rovira i Virgili University (URV) have analysed the environmental and human health impacts of an alternative fuel that solves various problems simultaneously. This is the solid waste from the water treatment plants of large cities.

The scientists have carried out the first study into this method at a cement plant in Vallcarca (Catalonia), which has been producing cement for more than 100 years, and they confirm in the latest issue of the journal Environmental Science and Pollution Research that it is “the best option for getting rid of mud that would have had to be dumped elsewhere, while also powering the plant”.

[...] Up to 20% of the fossil fuel energy used at the Catalan plant has now been substituted for the fuel from waste water treatment plant mud.

One of the most important issues for the URV scientists is the reduction in environmental impact, and consequently the health risks for people living near the plants. The experiment with the mud has led to a 140,000 tonne reduction in CO2 emissions between 2003 and 2006, and will have limited the potential deaths from exposure to chemical pollutants. In addition, the study shows that using this green fuel would reduce the cancer rate by 4.56 per million inhabitants.

The researchers say it is essential to carry out separate studies for each plant because “we still don’t know whether this will be positive for the whole cement industry”, according to Domingo. However, if the conditions are right, using mud from waste water treatment plants in cement factories is “a very good solution”, he concludes

Source: Plataforma SINC, ScienceDaily, 23 Jun 2009

Biogas: Chilean water utility inaugurates largest plant in South America

Chilean natural gas distributor Metrogas and water utility Aguas Andinas started up operations at the country’s first biogas plant installed at the Farfana water treatment complex on the outskirts of Santiago. The plant will produce 24Mm3/y of biogas and replace about 14Mm3/y of natural gas. “This is the only place in the world where biogas produced by a water treatment facility ends up being used directly in homes,” Metrogas president Matías Pérez Cruz said, adding that the biogas plant is the largest in South America. Investment in the project totaled 3bn pesos (US$5.3mn).

Source: BNamericas [subscription site], 14 May 2009

Meanwhile in Brazil, officials from the Japan International Cooperation Agency (JICA) and Paraná state water utility Sanepar [have met] to discuss projects to expand power generation sewage treatment plants. [...] Since 2008, Sanepar has been producing electric power from its [Ouro Verde sewage treatment plant in Foz do Iguaçu]. The plant produces energy for its own operations and the surplus is sold to power company Copel. [Sanepar wants to] extend the successful experience of Foz do Iguaçu to all [its] sewage treatment plants.

Source: BNamericas [subscription site], 25 May 2009

Upflow biofilters: treating septic tank effluent in squatter settlement in Nepal

Thirty-one households in Narayan Tole squatter settlement near Maharajgunj of KMC-3 , Kathamdu, have recently constructed ‘up-flow bio-filters’ to treat septic tank effluent. They have constructed two such filters spread in over 342 sq ft area with the financial and technical support of UN-HABITAT Water for Asian Cities Programme Nepal, WaterAid Nepal and Lumanti Support Group for Shelter.

Only 16 households in the area had toilets until a year ago. They used to let their toilet waste mix directly into nearby rivers. [...] All the households in the area now have toilets. They have constructed a 180-metre-long sewer to channel the toilet waste to the filters.

The filter first separates solid and liquid wastes and treats the liquid waste. After the treatment, the waste water [flows] into the rivers while the solid waste remains in the tank. The bio-filters were constructed with Rs. 0.2 million collected from the donors and locals. The locals have formed Narayan Tole Sudhar Samiti (NTSS) to take care of the filters.

Kalpana Karki, treasurer of the Samiti, told that it collects Rs. 35 per month from each household for the maintenance of the filters. [...] “We will use the digested solid waste as fertilizer in our fields,” Karki said.

Related news: Nepal, Kathmandu: squatters seek NGO help to defeat river pollution, Source Weekly, 15 Dec 2008

Source: NGO Forum,10 Feb 2009

South Africa: Joburg Water, University Agree to expand research expertise

Johannesburg Water (JU) and University of Johannesburg (UJ) have signed a Memorandum of Understanding [on collaboration] on water and sanitation research and development projects [...] specifically in water nanotechnologies, water purification, waste water treatment and innovation in water analysis.

Mr Jones Mnisi, Acting Chief Operation Officer, Johannesburg Water (JW). and Prof Derek van der Merwe, Pro Vice-Chancellor and Vice-Principal, University of Johannersburg (UJ) at the signing of the Memorandum of Understanding (MoU) at Johannesburg Water on Friday, 16 January 2009. Photo: UJ.

Read more: Gabi Khumalo, Bua News / allAfrica.com, 16 Jan 2009 ; Johannesburg Water, 16 Jan 2009

Dow’s Reuse of Municipal Wastewater Wins 2008 ICIS Innovation Award

The Dow Chemical Company’s re-use of municipal wastewater at its Benelux site in Terneuzen, The Netherlands was named the winner of the Most Innovative Corporate Social Responsibility Project in the 2008 ICIS Innovation Awards.

[...] The site uses treated household wastewater to produce high pressure steam and, as recycled water, in its cooling tower. This is [claimed to be] the first time that municipal wastewater is being re-used on such a large scale in the industry, exceeding 2.6 million gallons per day. The project is the result of [a public-private partnership] between Dow, the water treatment provider Evides and the Zeeuws-Vlaanderen Water Board.

[...] Dow already [wants to replicate the approach in] other regions such as the Middle East and China, where water is “the most precious commodity.”

Source: European Water News, 11 Nov 2008

Constructed wetlands: model wastewater treatment plant, Nepal

Dhulikhel municipality constructed a community-based wastewater treatment plant cum biogas at Srikhandapur-9, in Kavre district that generates cooking gas for locals, fertilizers for farmers and ultimately sends clean water into the river.

Six-horizontal reed bed treatment systems [wetlands] of 175 cubic meters and two-Bio-gas reactors of 75 cubic meter capacity each have been installed over four-Ropanis of land adjoining the sewage pipe of over 200 households for collection of wastewater.

[...]

The UN-HABITAT [through the Water for Asian Cities programme] and Dhulikhel Municipality supported Rs. 53, 00,000 and Rs. 17, 00, 000, respectively. Environment and Public Health Organization (ENPHO) provided technical assistance and training to locals in maintaining the system. The locals volunteered with masonry and contributed over Rs. 10, 00,000.

[...]

The plant generates over 30-kilogram cooking gas and equal amount of fertilizer everyday when the plant becomes fully operational [in October 2008].

Source: NGO Forum, 29 Sep 2008