Ventilated Improved Pit (VIP)

Transcription

1 Ventilated Improved Pit (VIP) Item Qty Unit Rate Amount Cement (50 Kgs bags) 6 bags Material Estimate Pour-flush squatting pa 1 No Pipe 100mm or 150mm diameter 1 No Sliding bolt 1 No Tower bolt 1 No Handle 2 No Nails 3 Kgs Hinges 3 No Timber 5 pcs Sand 3 cubic meters Gravel 2 Cubic meters Stone 2 Cubic meters Roofing nails 0.5 Kg Nails 4 and 3 2 Kg Wood 1 x 12 3 pcs Wood 2 x 3 5 pcs 3 feet roofing sheet 2 pcs Skilled labour 2 work-day Unskilled labour 2 work-day GHS

2 Ventilated Improved Pit (VIP) The VIP technology comprises of a pit, cover slab, privy room and a vent pipe. The pit and cover slab forms the sub structure and the privy room and vent form the superstructure. The pit may be lined or unlined depending on the stability of the soil. Also the pit may be elevated above ground based on the level of the water table. Continuous airflow through the top-structure and above the vent pipe removes smells and vents gases to the atmosphere. A darkened interior is maintained causing insects entering the pit to be attracted towards the light at the top of the vent pipe and trapped by the fly screen. Principles of Operation Excreta and anal cleansing material drops into the pit where the organic material decomposes and excess liquids percolate into the surrounding soil. Natural airflow through the top-structure and moving across the top of the vent pipe removes smells and vents gases from the pit to the atmosphere. A darkened interior is maintained causing insects entering the pit to be attracted towards the light at the top of the vent pipe and trapped by the fly screen. The faecal Sludge that is generated from the pit is manually removed and buried or may be transported for further treatment by composting. This latrine technology is best suited to rural, peri-urban and some parts of urban areas where there is land available for possible relocation when pits get full. Advantages and disadvantages No. Advantages Disadvantages 1. Can be built and repaired with locally available materials 2. Low (but variable) capital costs depending on materials and pit depth Flies and odours are normally noticeable Low reduction in BOD and pathogens with possible contamination of groundwater 3. Small land area required Costs to empty may be significant compared to capital costs 4. Flies and odours are significantly reduced (compared to non-ventilated pits) Sludge requires secondary treatment and/or appropriate discharge

3 Simple Pit Latrine Item Qty Unit Rate Amount Tower bolt 1 Number Material Estimate Handle 2 Number Nails 3 Kilograms Hinges 3 Number Wood 1 x 8 3 Pieces Wood 2 x 3 5 Pieces Stone 2 Cubic meters Skilled labour 10 Work-day Roofing material (thatch, etc) As needed Unskilled labour 3 Work-day GHS

4 Simple Pit Latrine Simple pit latrines are one of the oldest forms of formal sanitation in the world. It is the basic form of improved sanitation. The pit latrine is based on the use of a single dug pit to collect and store excreta. It consists of a square, rectangular or circular pit dug into the ground, covered by a slab with a hole through which excreta and sometimes anal cleansing material fall into the pit. A seat or a squat hole with foot rests may be installed depending on the user preference. The latrine may be covered with a superstructure with a door to provide privacy and protection from bad weather and unwanted guests eg snakes and other reptiles. A latch may be provided or improvised to ensure privacy. This latrine technology is best suited to rural and peri-urban areas where there is land available for possible relocation when pits get full. Principles of operation Excreta and anal cleansing material in the pit decompose through bacterial action, fungal attack and consumption by other organisms. The decomposition process may take place in the presence of oxygen (aerobic) or without oxygen (anaerobic). In most pits fresh excreta is initially decomposed aerobically but as it is covered by new layers of excreta conditions rapidly turn anaerobic. There are several options for managing the sludge when the pit is full. If there is space, the pit can be filled with soil and planted with a tree, as per the fill and Cover, and a new pit latrine built. This is generally only possible when the superstructure is mobile. Alternatively, the Faecal Sludge that is generated from the pit is manually removed and buried or may be transported for further treatment by composting. This latrine technology is best suited to rural and peri-urban areas where there is land available for possible relocation when pits get full. Advantages and disadvantages No Advantages Disadvantages 1 Can be built and repaired with locally available materials Poor design and prone to collapse because pits are not lined. Collapse is common in areas where the soil is unstable. 2 Does not require a constant source of water Nuisance from flies and mosquitoes (and sometimes cockroaches); 3 Low (but variable) capital costs depending on Bad odours; materials 4 Easy to operate and maintain Difficulty with emptying pits once they are full. 5 Slab and shelter can be reused Low reduction in BOD and pathogens 6 Separates excreta from users

5 Kumasi Ventilated Improved Pit (KVIP) Item Qty Unit Rate Amount Cement (50 Kilograms bags) 6 Bags Material Estimate Pipe 100mm or 150mm diameter 2 Number (3m long) Sliding bolt 1 Number Tower bolt 2 Number Roofing nails 0.5 Kilograms Handle 2 Number Nails 4 and 3 2 Kilograms Hinges 3 Number Wood 1 x 8 3 Pieces Wood 2 x 3 5 Pieces Stone 2 Cubic meters 3 feet roofing sheet 2 Pieces Sand 1.5 Cubic meters Skilled labour 2 Work-day Unskilled labour 2 Work-day Wood 2 x 3 5 pcs 3 feet roofing sheet 2 pcs Skilled labour 2 work-day Unskilled labour 2 work-day GHS

6 Kumasi Ventilated Improved Pit (KVIP) An improvement to the traditional VIP is the Kumasi Ventilated Improved Pit (KVIP) which is designed with double pits. The double Pit VIP has almost the same design as the Single Pit VIP with the added advantage of a second pit that allows it to be used continuously and permits safer and easier emptying. By using two pits, one pit can be used, while the content of the second rests, drains, reduces in volume, and degrades. When the second pit is almost full (the excreta is 50 cm from the top of the pit), it is covered, and the content of the first pit is removed. Due to the extended resting time (at least 1 or 2 years after several years of filling), the material within the pit is partially sanitized and humus-like. Principle of Operation The principles of operation are the same as for the VIP toilet. One pit is used until filled to within about half a meter of the top. The pedestal and vent pipe holes are to be completely sealed before the other pit is used. The contents of the first pit are dug out after a period of at least two years, once the contents have become less harmful. Due to the extended resting time (at least 1 or 2 years after several years of filling), the material within the pit is partially sanitized and humus-like. The faecal Sludge that is generated from the pit is manually removed and buried or may be transported for further treatment by composting. This latrine technology may be appropriate for rural, peri-urban and urban areas where there is land available for possible relocation when pits get full. Advantages and disadvantages No. Advantages Disadvantages 1. Longer life than Single VIP (indefinite if maintained properly) Manual removal of humus is required 2. Excavation of humus is easier than faecal sludge Possible contamination of groundwater 3. Significant reduction in pathogens Higher capital costs than Single VIP; but reduced operating costs if self-emptied 4. Potential for use of stored faecal material as soil conditioner 5. Flies and odours are significantly reduced (compared to non-ventilated pits) 6. Can be built and repaired with locally available materials

7 Enviro Loo waterless Toilet Contact for further information South Africa Enviro Options (PTY) Ltd. Tel: +27 (0) Local Contact Holbrook Environs Ltd. Tel: +233 (0) GHS

8 Enviro Loo waterless Toilet The Enviro Loo is a dry or waterless sanitation system that employs a dehydrating process over a lengthy retention period with an ancillary, lesser composting process. It uses no water and chemicals. It enables the processes of dehydration and evaporation to occur naturally without any soil or water contamination as the decomposition takes place in a sealed unit. In the design there is no contact between people and the system. The annual maintenance and servicing costs are minimal. The Enviro Loo comprise a superstructure, urinal evaporative tank, ventilation extracting unit, outlet vent pipe, vent pipe wall bracket, urinal bowl and toilet bowl. Principles of Operation The system separates liquid and excreta as it enters the container through a custom designed ceramic toilet bowl. Liquid waste drains to the bottom of the container while excreta remains on the drying plate. Both the liquid and excreta are exposed to a continuous flow of air that is driven through the unit by the forced aeration ventilation system. The movement of air is assisted by the ventilation extraction unit positioned on top of the outlet vent pipe with air being drawn into the container through the inlet vent pipes and toilet bowl. As air moves through the system, it dehydrates the excreta as it migrates down the sloped, ridged, perforated drying plate. This causes the liquid that has drained to the bottom of the container to evaporate. The sunlight absorbed by the black inspection cover increases the ambient temperature within the container. The intense heat, prolonged retention periods and oxygen-rich air drawn in through the toilet bowl and side air inlets, dehydrate and decompose the excreta. Through biological activities, excreta is converted to an odourless dry stabilised material. Advantages and disadvantages No Advantages Disadvantages 1 It is odourless Cannot be built and repaired with locally available materials 2 Does not require a constant source of water High capital/ initial cost 3 Permanent installation, does not require relocation 4 No chemicals required 5 No sewage treatment facility required 6 Separates excreta from users

9 Composting latrine Material Estimate Item Cement (50 Kgs bags) Pipe 100mm or 150mmdiameter (10 long) Sliding bolt Tower bolt Handle Nails Hinges Wood 1 x 12 Wood 2 x 3 Sand Gravel Stone Skilled labour Unskilled labour Wood 1 x 12 Wood 2 x 3 3 feet roofing sheet Skilled labour Unskilled labour Qty Unit Bags No No No No Kgs No pcs pcs Cubic meters Cubic meters Cubic meters work-day work-day pcs pcs pcs work-day work-day Rate Amount GHS

10 Composting latrine In this latrine, excreta fall into a watertight tank to which ash or vegetable matter is added. If the moisture content and chemical balance are controlled, the mixture will decompose to form a good soil conditioner in about four months. Pathogens are killed in the dry alkaline compost, which can be removed for application to the land as a fertilizer. There are two types of composting latrine: in one, compost is produced continuously, and in the other, two containers are used to produce it in batches. Principles of Operation This type of latrine recycle nutrients from human excreta for agricultural production. The deposited faecal matter is dried by exposure to heat or the sun and the addition of lime, ash, sawdust or earth, which controls the moisture content. Vegetable or other organic waste can also be added to control the chemical balance. The latrine contents are then isolated from human contact for a specified period to reduce the presence of pathogens and make the waste safe for handling. This period should be at least one year. Advantages and disadvantages No Advantages Disadvantages 1 A valuable humus is produced. More difficult to construct than simple pit latrines. 2 Considerable odour reduction High level of user awareness required

11 Urine Diverting Dry Toilet (UDDT) Material Estimate Item Qty Unit Rate Amount Cement (50 Kilogramss bags) 15 bags Eco-san squatting pan 2 Number Pipe 100mm or 150mm diameter 3 Number (3m long) Sliding bolt 2 Number Tower bolt 1 Number Handle 1 Number Nails 5 Kilogramss Hinges 3 Number Wood 1 x 8 3 Pieces Wood 2 x 3 10 Pieces Sand 2.5 Cubic meters Gravel 1 Cubic meters Stone 3.5 Cubic meters Skilled labour 2 Work-day Unskilled labour 2 Work-day Wood 2 x 3 5 pcs 3 feet roofing sheet 2 pcs Skilled labour 2 work-day Unskilled labour 2 work-day GHS

12 Urine Diverting Dry Toilet (UDDT) The urine diverting dry toilet (UDDT) is a sanitation facility for households and public facilities. A Urine Diverting Dry Toilet (UDDT) is a toilet that operates without water and has a divider so that the user, with little effort can divert the urine away from the faeces. UDDTs may be constructed with two (2) adjacent dehydration vaults or one single vault with interchangeable containers. This technology was originally promoted in connection with safe reuse of excreta. However, the primary focus of UDDT implementation has gradually shifted from that of excreta reuse to the broader objective of creating odourless, dry and versatile latrine. This technology does not require water, therefore it is suitable for locations where there is scarcity of water or where the water supply is not always dependable. The alternating use of the two pits allows the toilet to be used continuously without any interruption. When the first pit becomes full, the drop-hole is closed and sealed and the second pit is put into use. When the second pit becomes full, the emptying hatch of the first pit is dismantled and the decomposed contents can be removed and safely used as a plant fertiliser. The emptying hatch is then re-closed and the pit put back into use while the second pit is sealed. Principles of Operation The UDDT toilet is built such that urine is collected and drained from the front area of the toilet, while faeces fall through a large chute (hole) in the back. Depending on the Collection and Storage/Treatment technology that follows, drying material such as lime, ash or earth should be added into the same hole after defecating. It is important that the two sections of the toilet are well separated to ensure that a) faeces do not fall into, and clog the urine collection area in the front, and that b) urine does not splash down into the dry area of the toilet. During the dehydrating process moisture evaporates from the faeces and microbes degrade the organic material leading to significant reduction in the numbers and viability of pathogens. Urine is collected in containers for direct use or stored for further processing. Storage of urine generally leads to a raise of ph and consequent hygienisation. Advantages and disadvantages No Advantages Disadvantages 1 Avoids contamination of water sources and soil High capital/initial cost 2 Composting of human waste for use as a natural fertilizer UDDT in urban areas require special attention in the collection of urine and composted faecal sludge 3 There is no need of emptying the pits Is prone to clogging with faeces and misuse 4 It is applicable for water logged, water scarce, coastal and rocky areas Slightly more difficult to clean compared to other technologies 5 Significant reduction of pathogen by drying Difficult to use for small children 6 Promotes soil fertility and improved crop production More effort to put into awareness raising and habit changing

13 Pour-Flush Toilet without Water-Seal, Installed On Direct Pit (Ventilated Pit) Roofing Vent pipe Pour-flash bowl without water seal Pit lining Material Estimate Item Qty Unit Rate Amount Cement (50 Kilograms bags) 6 Bags Pour-flush squatting pan without 1 Number water seal Pipe 100mm or 150mm diameter 1 Number Sliding bolt 1 Number Tower bolt 1 Number Handle 2 Number Nails 4 and 3 4 Kilograms Hinges 3 Number Timber 5 Pieces Sand 3 Cubic meters Gravel 2 Cubic meters Stone 2 Cubic meters Roofing nails 0.5 Kilograms Wood 1 x 8 3 Pieces Wood 2 x 3 5 Pieces 3 feet (900mm) roofing sheet 2 Pieces Skilled labour 2 Work-day Unskilled labour 2 Work-day Unskilled labour 2 work-day GHS

14 Pour-flushed toilets The pour flush toilet has a water seal (U-trap or siphon) that prevents odours and flies from coming back up the pipe. Water is poured into the bowl to flush the toilet of excreta; approximately 2 to 3 litres are usually sufficient. The quantity of water and the force of the water (pouring from a height often helps) must be sufficient to move the excreta up and over the curved water seal. Both pedestals and squatting pans can be used in the pour flush mode. Due to demand, local manufacturers have become increasingly efficient at mass-producing affordable pour flush toilets and pans. Principles of Operation A pour-flush toilet is like a regular flush toilet except that instead of the water coming from the cistern above, it is poured in by the user. The pour-flush (PF) latrine comprises two principal components: the latrine pan with its integral waterseal and either single or twin leach pits. The water seal is effective at preventing odours and fly control. The excreta flushed into the leach pit are biodegraded under both anaerobic and aerobic conditions. By natural biodegradation and the action of time and temperature, excreta is rendered harmless, and the pit will contain a friable humus that is both safe to use and inoffensive. Advantages and disadvantages No Advantages Disadvantages 1 Water required for satisfactory operation is usually about 2-3 litres per flush 2 High social acceptability especially in Moslem communities where water is used for anal cleansing 3 With minimum householder care and maintenance, odor and insect nuisance are negligible 4 Both adults and children can use the toilet without fear Trap may be regularly blocked by bulky anal cleansing materials Possible ground water contamination from leach pit especially in areas with high water table

15 Pour-Flush Toilet with Water-Seal, Installed On Ventilated Pit Material Estimate Item Qty Unit Rate Amount Cement (50 Kilograms bags) 6 Bags Pour-flush squatting pan with water trap 1 Number Pipe 100mm or 150mm diameter (3m long) 2 Number Sliding bolt 1 Number Tower bolt 1 Number Handle 2 Number Nails 4 and 3 4 Kilograms Hinges 3 Number Timber 5 Pieces Sand 1.5 Cubic meters Gravel 1.5 Cubic meters Stone 2 Cubic meters Roofing nails 0.5 Kilograms Wood 1 x 8 3 Pieces Wood 2 x 3 5 Pieces 3 feet (900 mm) roofing sheet 2 Pieces Skilled labour 2 Work-day Unskilled labour 2 Work-day 12mm diameter mild steel reinforcement bars 3 Number GHS

16 Pour-flushed toilets The pour flush toilet has a water seal (U-trap or siphon) that prevents odours and flies from coming back up the pipe. Water is poured into the bowl to flush the toilet of excreta; approximately 2 to 3 litres are usually sufficient. The quantity of water and the force of the water (pouring from a height often helps) must be sufficient to move the excreta up and over the curved water seal. Both pedestals and squatting pans can be used in the pour flush mode. Due to demand, local manufacturers have become increasingly efficient at mass-producing affordable pour flush toilets and pans. Principles of Operation A pour-flush toilet is like a regular flush toilet except that instead of the water coming from the cistern above, it is poured in by the user. The pour-flush (PF) latrine comprises two principal components: the latrine pan with its integral waterseal and either single or twin leach pits. The water seal is effective at preventing odours and fly control. The excreta flushed into the leach pit are biodegraded under both anaerobic and aerobic conditions. By natural biodegradation and the action of time and temperature, excreta is rendered harmless, and the pit will contain a friable humus that is both safe to use and inoffensive. Advantages and disadvantages No Advantages Disadvantages 1 Water required for satisfactory operation is usually about 2-3 litres per flush 2 High social acceptability especially in Moslem communities where water is used for anal cleansing 3 With minimum householder care and maintenance, odor and insect nuisance are negligible 4 Both adults and children can use the toilet without fear Trap may be regularly blocked by bulky anal cleansing materials Possible ground water contamination from leach pit especially in areas with high water table

17 Biofil Toilet Based on Manufacture s specification GHS

18 Biofil Toilet Biofil digesters are on-site waste treatment systems. Living organisms in an enclosed environment treat organic degradable matter through natural aerobic decomposition. Wastewater and faecal matter enter a rapid separation chamber/section for the separation of solids and liquid content of the waste. Separation is achieved by the function of a porous composite. Bacteria and other micro and macro organisms (worms) degrade solid faecal matter. Liquids are eventually filtered out into the soil. Principles of operation Excreta and wastewater enter at the top of the Biofil digester where rapid separation of solids and liquid contents of the waste occurs. Bacteria, other organisms such as worms degrade solid faecal matter. All liquids are organically filtered out of the bottom of the digester and drained into the soil where further and final decomposition occurs. Other solids (toilet paper & all degradable anal cleaning material) are decomposed and converted into rich & safe soil. Due to its relatively small footprints it is a suitable option for peri-urban and urban areas where there is water available for flushing. Advantages and disadvantages No Advantages Disadvantages 1 Ground water not affected; Water is directed into top soils where microbial activities are most active. Nutrients are removed by soil bacteria decomposition Final effluent may need secondary treatment to ensure total elimination of faecal coliforms. 2 Suitable for soil with low water table High initial capital cost 3 Hygienic to use In water logged areas, effluent has to be treated before final discharge. 4 Minimal odour After long periods (more than five (5) years) sludge may accumulate in the digester. 5 Less water required (1.5 litres for microflush) 6 Does not require large land area hence suitable for densely populated areas