The waste water from the hospital, the buildings of Bhusaldada village, the canteen and the compound buildings will have to be transported to the treatment plant.
- The waste water from the hospital and is the so called “black water” It is waste from the toilets etc. and needs at least two types of treatment. Hotels and houses close to the entrance of the hospital are connected to pipes that carry the black water to a gulley outside the gate of the hospital. The waste water of this village and the hospital will be piped and brought to the water treatment plant.
- The waste water from the houses and the waste water of the washing machines of the hospital are disposed of at several locations. All houses have a septic tank with sink pit. These septic pits will be abandoned as it is more difficult to maintain 10 small septic tanks than two big ones. The black water of the houses is piped and brought to the septic tanks.
- Up till now, placenta’s, from the maternity unit are being burned in the incinerator.
This practice was opposed by a number of the Nepali staff. The Maternity Hospital in Kathmandu uses a bio gas installation to dispose of placentas. In 2014 the Carl Friedericks building was completed. In that quarter, live about 50 staff members and has several teaching rooms. Besides that, the black water system is separated from the grey water system. An ideal situation to connect the black water system to a biogas plant; where also placenta’s can be disposed of. This biogas plant will be a part of the system.
The proposed infrastructure is given on page 16. We will use pipes of different diameters to bring this black and grey water to the first and second treatment plants. After the treatment is completed the effluent of the second treatment plant will be disposed of in the same gulley through which now the black water of the hospital with the surrounding hotels and houses is disposed of. The water quality of the water in this gulley will improve dramatically.
First line treatment
On the hospital compound, first-line treatment is available for all buildings except the hospital. The living quarters, guesthouse etc. are all equipped with a septic tank. The black water from the hospital is not given any treatment. Therefore, a first-line treatment plant should be built for the hospital. The waste water from the hospital, 40 m3 per day, should be put through a standard septic tank with a capacity of 224 m3. It was considered to use an improved septic tank named an Anaerobic Baffled Reactor (ABR). It was decided to use an ordinary septic tank as an Anaerobic Baffled Reactor (ABR) has a little more efficiency (5-10%), but is more complicated to operate. This solution is thought to be the most cost effective. Two septic tanks with a capacity of 112 m3 will be build. The inside dimensions will be 14,00 x 4 x 2 meters. These tanks will be located near the road to the nursing campus. This location gives the opportunity to remove the sludge into trucks to be brought to a disposal area.
Standard septic tank
Location of the two septic tanks
- Second line treatment
The effluent from the septic tanks, the water from the washing room facility from the hospital has to be treated in a secondary treatment plant. The choice has been made for a “Moving Bed Biofilm Reactor” (MBBR) that will be placed behind the septic tanks. The system is mounted into a container in which the process takes place. For this system 7,5 kWh is needed, but no additives are required. The system produces about 100 liters sludge per day and is dewatered at site. This sludge can be used a manure. The system is manufactured in India in a 15 feet container and be brought to the site by truck.
The effluent from this waste water treatment system is up to international standards. The effluent will be discharged into the gulley where at the moment the hospital waste water finds its way down the hill. This will have a huge impact on the surroundings as further downhill near this gulley springs exist from where people derive their drinking water from.
Schematic length section of MBBR
- Implementation of the project
The total costs to realize this project are estimated at USD 413.000.
The main hazard for the local people living close to the waste water gulley is the waste water from the hospital and Bhusaldada village, as no treatment takes place. The waste water from the compound houses have a septic tank and a sink pit. The effluent of the sink pits is mainly disposed of into barren land and normally people don’t come into contact with this waste water. As the costs to construct this waste water system is high it is decided to divide the project into three phases. These being:
- Phase 1: We build first the biogas installation. This is a standalone installation and can function without the need for the rest of the project. It is relatively cheap and quick to be realized. In this way we can solve the problem of the disposal of the placenta’s quickly. The costs will be USD 8,000.
- In phase 2 we will build a waste water system for the hospital and Bhushaldanda only. We will collect all the waste water from the hospital (including the waste water from the laundry room) and Bhusaldanda village and bring it through a pipe to the waste water treatment plant, the MBBR. The capacity of this MBBR is for the entire project. In this way the waste water that effects the health of the local people is treated. After the realization of this phase, the water that flows through the waste water gulley will be clean water that safely can be used for irrigation purposes. The costs for this part of the project, has been estimated at USD 260,000.
- In phase 3 we will connect all compound buildings to a pipe system that takes all waste water to the already existing water treatment plant (the septic tanks and MBBR system) The costs for this phase comes to USD 145,000.
After phase 2 has been realized the health hazard of the people living close to the waste water gulley has been solved. Phase 3 can be realized at a later date as it doesn’t effect the health of people.