PowerPoint Presentation

Storage and transport logistics

Lecturer: Mariska Ronteltapm.ronteltap@unesco-ihe.orgCourse 2 Unit 3

Part A Urine storagePart B - Faeces storagePart C Transport logistics overviewPart D Detailed analysis of transport options2This unit deals with which part of the sanitation system?+ storage at household or community level

+ storage at household or community level3Course 2 Unit 3

Part A: Urine storageCourse 2 Unit 3Note: Urine is normally stored pure, or with as little water added as possible

All technical details presented in this Part A regarding urine pipes and urine storage tanks are taken from Kvarnstrm et al. (2006), Appendix 2 Purposes of urine storageSanitisation of the urine, which will occur over time (increased pH due to urea conversion to ammonia; time itself also results in pathogen kill see Course 2 Unit 1 Part A)To bridge the time in between collection events by transport vehicle Farmers needs for urine fertiliser is not constant all year round, but mostly just before sowing and in the beginning of the growth period (see also Course 3 Reuse of ecosan products)

Very simple urine collection vessel:Plastic 20 L jerrycan connected to outlet of UDD toilet squatting pan (may need frequent emptying depending on number of users). CREPA in Burkina Faso (seen October 2006)What is the required urine storage tank volume?Vstorage = Npeople purine temptying

VstorageRequired storage volume at household levelNpeopleNumber of people in household, e.g. 4.5purine

Urine production per person and day (see Course 1 Unit 2; e.g. 1.3 L/cap/d)temptying

Time between emptying events, e.g. 30 days if emptied once per monthThen in this example: Vstorage = 4.5 cap 1.3 L/cap/d 30 d = 176 LEquation based on household urine production and days between tank emptying events:Costs of urine storageUrine storage can be a major cost item in a large-scale urban ecosan project!Often a trade-off is made between the theoretical storage time required for complete sanitisation (see Course 2 Unit 1 Part A) and the expenditure that is to be made for the urine storage tanksThe longer the urine storage time, the larger the urine storage tank and the higher its costKey process during urine storage: degradation of urea to ammonia in waterCO(NH2)2 + 3 H2O 2 NH4+ + OH- + HCO3- NH4+ + OH- NH3(aq) + H2O

UreaAmmoniumAmmonia (aq = in solution)Hydroxyl ion (pH rise)Possible problems with urine storage installationsBlockages in pipe from toilet to urine storage tank (see Course 1 Unit 3 Part A for details)

Odour (from ammonia)

Intrusion of groundwater (for underground tanks)

Nitrogen losses (in the form of ammonia)

A lot of the experience with urine storage comes from Sweden because it is currently the country with the most wide-spread use of urine-diversion toilets (see next slide)

A selection of places in Sweden where urine diversion is installed for ten households or more

Since the middle of the 1990s at least 135,000 urine-diverting toilets have been installed in different settings in Sweden. Most of the installations are urine-diverting liners made of plastic for outhouses at summerhouses or plastic urine diversion with dry collection of faeces, but at least 15,000 are made of porcelain and have either dry- or water-flushed collection of faeces. (Source: Kvarnstrm et al. (2006), page 21)

Map of Southern part of Sweden (Picture by Johan Palmcrantz & Co.)Technical requirements for urine piping systemParameterSmall systems with only one toilet on each urine pipeLarger systems with several toilets on one urine pipeU-bend required (for odour control)NoYesPipe diameter inside the houseAt least 25 mmAt least 75 mmaOutdoor pipesAt least 110 mmAt least 110 mmSlopeAt least 4%At least 1%Pipe materialPlastic (e.g. PVC)Need to avoidObstacles slowing down the flow, e.g. sharp bendsLength of piping system< 10 mNo limit but provide possibility to inspect, flush and clean the pipes a Where the pipes can be easily cleaned and/or disassembled, 50 mm can be accepted, at the expense of regular maintenance e.g. flushing every few years.

Guiding principles for urine pipesPiping in the system should be minimized as much as possible (to limit the time the urine is in the piping system and thus the degradation of urea and risk of precipitation in the system)To prevent odours, the piping system should be only sparingly ventilated, pressure equalization is enough To maximize the flow rate of the urine and the sludge, the insides of the pipes should be smooth and flow restrictions, e.g. sharp 90 bends, should be minimizedRemember: Long-distance piping for urine would not be a good idea!

Other specifications for the urine piping systemThe possibility to inspect, flush and clean the pipes in both directions should be provided where there is a sharp bend in the piping, at all transitions, e.g. from vertical to horizontal piping and where the pipes leave the house. Manholes outside the house shall be equipped with child safe lids that are water tight. When the collection container is outside of the toilet room, it is also important that the pipe ends close to the bottom of the collection container to avoid air flow through the pipe into the toilet room.The urine pipe is preferably located in the same piping trench as other wastewater pipes. It should be clearly marked, so that it is clearly distinguishable from the other pipes.It is essential to avoid sedimentation pockets and thus it is essential that a negative slope is avoided in all parts of the pipe system.

Course 2 Unit 3Materials for urine storage tanksUrine is very corrosive and if possible metals should be avoided altogether in the systemPossible options:Plastic tank, plastic drumsBig rubber bagsDigging a hole in the ground and covering the ground with polythene sheets to create a basin (covered with polythene sheets as well)High-quality concrete (expensive)At the farmers end urine could possibly be stored directly in the ground itself (without a plastic liner), see EcosanRes Discussion Forum on 10 April 2006 by Hkan Jnsson, plus postings thereafter

This picture shows the plastic urine storage tanks at Kulln, Sweden during the construction process. The tanks will be covered with soil. Photo: Mats Johansson.(Source: Kvarnstrm et al. (2006), page 36)Technical requirements for urine storage tanksTanks need to be water-tight and robustCare should be taken to prevent groundwater leaking into the pipe system All connections in the ground must be completely tight (i.e. welded or glued, or if possible, avoided altogether) to minimize the risk for intrusion of groundwater If possible, connections in the ground should be avoided all together

Very simple urine storage tank:A number of plastic 20 L jerry-cans (from UDD toilet shown in slide 4). CREPA in Burkina Faso (seen October 2006)

Urine storage tank (4 tanks of 2.5 m3 each) made of polyethylene in the basement of the GTZ head office building in Eschborn, near Frankfurt in Germany, with sampling and level indicator devices (installed in August 2006)

Level indicator for urineDocking station for urine tankers (insulated pipe for winter temperatures in Germany)Example: The first large-scale urine collection system with urine diversion in Stockholm, Sweden

The system was established in 1997 and urine from the Understenshjden, Palsternackan and Gebers residential areas and the Bommersvik conference centre is transported to the Lake Bornsjn area where it is stored and replaces chemical fertilizer in agriculture.

Short facts:Connected households: 130 + 1 conference centre.Type of toilets: 50% Dubbletten, 25% Gustavsberg and 25% Wost Man Ecology single flush.Glass-fibre tanks in each housing area 15 40 m3 each.Yearly volume of collected urine: 150 -170 m3.Storage tanks: 3 PVC balloon tanks of 150 m3 each.

Source: Kvarnstrm et al. (2006), page 20)

P. JenssenStorage takes place at Bornsjn, and the urine is used on fields in the background owned by the Stockholm Water Company.

Part B: Faeces storageCourse 2 Unit 3Course 2 Unit 3Different types of faeces collection require different types of storageType of faecesToilet typeType of storageType 1:Faeces without water (but with ash, sand, lime etc., and with or without toilet paper)UDD toilet; composting toilet

In the faeces vault of a UDD toilet In smaller buckets and then added to composting processType 2:Faeces with small amount of water (one litre of water per defecation) = blackwater Vacuum toilets (with or without UD) Toilets where faeces collected together with anal washwaterIntermediate storage possible, e.g. in septic tankType 3:Faeces with large amount of water (e.g. several litres of water per defecation) also called brownwater UD water-flush toilets Conventional water-flush toilets (mixed with urine) No storage - usually discharged to the sewer Could be stored in septic tankType 1 faeces is certainly the easiest to store and treat in a low-income settingStorage of Type 1 faeces (faeces collected without water)Faeces volumes are much smaller than urine volumes, hence its storage is easier to realiseFor waterless systems: Can be stored inside of faeces vault in a UDD toilet (typically one year), receiving primary treatmentFor secondary treatment, storage and treatment are combined, e.g. in anaerobic digestion or composting (will be discussed in Course 2 Unit 4 and 6)

Example: Faeces storage in the vault of a UDD toiletPhoto: Edward Guzha, Mvuramanzi Trust in Harare, ZimbabweStorage of Type 2 faeces (blackwater from vacuum toilets)

Top: Blackwater from vacuum toilets (without UD) after the macerator pump; this is fresh excreta over time the colour would turn black (anaerobic conditions).Right: Storage tanks for blackwater of 80 persons (they produce ~ 5.6 L/cap/d)Sneek, The Netherlands, March 2007Storage of Type 3 faeces (faeces plus water, from UD water-flush toilets)In the case of UD water-flush toilets in Switzerland and Sweden, the faeces-water mixture is not stored but discharged to the sewer and wastewater treatment plant

Research projects are ongoing to treat the faeces-water mixture with membrane bioreactors and other high-tech processesCourse 2 Unit 3You can imagine that Type 3 faeces are quite difficult to store and treat at low costWhat is the required faeces storage tank volume?Vstorage = Npeople pfaeces temptying

VstorageRequired storage volume at household levelNpeopleNumber of people in household, e.g. 4.5pfaeces

Faeces production per person and day (see Course 1 Unit 2; e.g. 50 L/cap/year see also next slide)temptying

Time between emptying events, e.g. 1 yearThen in this example: Vstorage = 4.5 cap 50 L/cap/year 1 yr. = 225 LEquation based on household faeces production and days between tank or vault emptying events:Specific faeces (or faeces-water) production to be used in calculationsType of faecesPfaeces to be used in equation on previous slideCommentsType 1:Faeces without waterAt excretion (wet): ~ 50 L/cap/year *

After drying:~ 10 L/cap/year

Remember, faeces at excretion are about 80% waterUsing the wet amount would be conservative for storage vault sizingType 2:Faeces with small amount of water = blackwater2044 L/cap/yearUsing the value of 5.6 L/cap/d measured in Sneek (remember 1 L per flush; therefore people flush 5.6 times per day)Type 3:Faeces with large amount of water = brownwater12 264 L/cap/yearAssuming people flush 5.6 times per day and 6 L per flush* Value from Sweden check for your country (see Course 1 Unit 2 Part B)Course 2 Unit 3

Part C: Transport logistics overviewCourse 2 Unit 3Definition of the word logistics:Logistics can be considered as a tool for getting resources, like products, services, and people, where they are needed and when they are desired. (www.wikipedia.org)2727

Urban ecosan logistical challenges: flow movements into and out of the urban areaArrows are indicating:Food and water in to the cityWater, urine, faeces out of the cityThe shorter the distances, the betterSafe transport options for different types of materials derived from excretaConsistency of materialTypes of excreta-based materialTransport optionCommentsDry Dried faeces from UDD toilet vaults Compost Household solid wasteTrucks, tractors, trailers, tricyclesSimilar to solid waste collection systemsLiquid and pumpable Faecal sludge (pit latrines, septic tanks) Digested sludge from anaerobic digestersVacuum tankersPipes and pumpsVacuum tankers: see next slidePipes and pumps: in most cases not cost-effective, unless distance are very short

Urine

Barrels or tanks on tricycle or truckPipes are not suitable for urine on its own, but possibly together with greywaterGreywaterSmall-bore sewersGreywater is too diluted to be transported in any other way than with pipesPumping with vacuum tanker

Source: ACTSTruck with a vacuum pump for blackwater removal, Bangalore, IndiaCourse 2 Unit 3

A quick coupling at the property line for rapid and safe emptying of a blackwater holding tank by vacuum trucks Commonly used to remove faecal sludge from septic tanks, pit latrinesDirect contact of the workers with the faecal sludge is minimized quite a safe technique Tanks may be mounted on carts pulled by tractor or animals smaller units possibleSource: Heeb et al. (2007)The classical technology for emptying of septic tanks, pits, etc. is by suction with a vacuum pump. A hose is introduced in the tank or pit and the content is sucked out. The direct contact of the workers with the sludge is significantly reduced and is therefore the safest technique available. The pump is usually connected to a truck-mounted tank of variable capacity. In this way the truck can access the plot, empty the facility and then directly transport the sludge to the disposal or treatment site. Tanks may be mounted on carts pulled by tractor or animals, a system being considerably cheaper and technically equivalent to truck mounted systems. Smaller units or vacuum tugs, consisting of smaller tanks and motor or hand-driven vacuum pumps may be used in situations where very narrow access do not allow large vehicles.

Manual handling normally comprises the use of shovels and buckets and may demand that the workers have to step into the pit, thus exposing themselves to great health risks. Manual handling should be eliminated wherever it is possible. However, manual handling will still be the final option when the use of vacuum pumps is excluded for certain reasons. Manual handling can be acceptable if the health risk to workers is minimized, i.e. when adequate protection measures by workers are used (gloves, masks, good hygiene). Most important is that workers be aware of the nature of the health risks to which they are exposed and that they know how to protect themselves. Training and targeted information may therefore be the most successful measures.

Source: (29)

Example of a vacuum tanker operation in industrialised countryThe photos on the next slide shows how a vacuum tanker is used at a highway restaurant in GermanyThe task is to empty the holding tank which is used for all the kitchen wastewater from the restaurantThere is a grease trap for the kitchen wastewaterThe hose from the vacuum tanker is placed in an access manholeOn the photo top right, the worker is jetting water into the storage tank to clean it out better and to allow better pumpingThe size of the vacuum tanker is 10 m3 plus 2 m3 of water for the cleaningOne can nicely see the safety precuations used, e.g. the bright clothing, gloves, boots with steel toe capsSeen January 2007, photos by E. v. Mnch

Low-cost vacuum tanker for emptying faecal sludge from pit latrines

Source: http://hq.unhabitat.org/cdrom/water/HTML/PDFs/vacutug.pdfCourse 2 Unit 3Vacuum tank (500 L) and pump/tug assembly with 5.9 kW petrol engine. For pit emptying with difficult access conditions. Ideally suited for micro-enterprise use

J. HeebSafety precautions during excreta handling and transportCritical points from a health risk perspectiveProtection measures when handling fresh and stored excreta:GlovesShoes Wash hands afterwardsStore material out of reach for people or animalsManual handling should be eliminated wherever it is possibleSource: Heeb et al. (2007)Since many source separating systems are decentralised systems not relying on pipes, manual handling of recyclates is sometimes necessary. Though for most systems, only the handling of treated substances is necessary, the handling is still one of the most critical points from a health risk perspective.However, if proper protection measures are taken the risk is minimized. It is therefore important to use protection when handling the material and that excavated material is buried immediately or stored out of reach for people or animals until proper maturation times have been reached. In addition to protective clothing as gloves and boots normal hygiene and washing after the emptying operation is ended is important.

Source: (29)Main issues with transporting dry solid material (faeces)Transport logistics could be linked to the citys solid waste management systemAmounts of dry faeces are much smaller than conventional solid waste Remember: dry mass of faeces ~ 30 g/cap/d; but solid waste production ~ 200 500 g/cap/d in cities in India (see Course 1 Unit 2 Part B)Could be a business opportunity for small private enterprisesIf containers are used inside of the vault for faeces collection, keep in mind the maximum weight that one or two people can move, when the full container is removed and exchanged for an empty one

Need to find suitable vehicles to fit type of access lanes

Dried faeces taken out of a double-vault UDD toilet vault (Slob (2005), p. 111)Main issues with transporting liquid material: urinePipes tend to block up, so cannot be transported by pipe over longer distanceRoad based transport most commonDistance to reuse site should be as short as possibleVery rough rule of thumb: approx. 120 km is maximum economical distanceDisadvantages of road based transport: CO2 emissions, noise, dust, increased traffic This is still a challenge for large scale ecosan in urban contextWhat transport distances would have to be covered in your city?Main issues with transporting liquid material: greywaterSmall-bore sewers is most likely the best solution (see Course 2 Unit 8)Course 2 Unit 3Main issues with transporting liquid material: faecal sludgeVacuum tankers are best solution (privately operated or operated by municipality)

But in reality, manual emptying with buckets is still common in low-income settings!

Many people cannot afford to pay for a vacuum tanker service and hence try to empty it themselves somehowUnsafe, manual pit emptying can look like this!

Photo taken in Ouagadougou, Burkina Faso, by Doulaye Kon, SANDEC/EAWAG, SwitzerlandThe health risks for this worker are incredibly high -let alone the lack of human dignity!Course 2 Unit 3

Part D: Detailed analysis of transport optionsCourse 2 Unit 3This part of the presentation builds on the work done by Marieke Slob (2005): Logistic aspects of ecological sanitation in urban areas Case study in low-income community in Delhi, IndiaAll photos and numbers in this Part D are taken from that excellent MSc thesis

Distinction between transport with a transfer (top row) and direct transport (bottom row)Transfer becomes necessary when haul distances increase to such a distance that direct transport is no longer economical, or when the destination can only be reached with a different means of transportIt is cheaper to haul a large volume of waste in large increments over a long distance than it is to haul a large volume of waste in small increments over a long distance

Slob (2005), p.43Broad options for the logistics systemPrimary collection systemRoadPipesSecondary collection systemRoadRailWaterAirPipes

Only relevant for longer distancesOnly possible for greywater, not for urineOnly possible for greywater, not for urineOverview of possibilities for main logistics systemMain logistics systemOperator of primary collectionMeans of collectionAnalogy with existing collection systemsPublic toiletsHousehold memberInside the body of household memberCommunal collection (households discharge their waste at predetermined locations). Refuse-collection vehicles visit these sites at frequent intervals to remove waste (secondary collection)Household member brings urine and/or faeces to a collection pointHousehold memberHousehold containersCollection vehicles collect urine and/or faeces at each householdCollection serviceHousehold container is switched for empty container or household container is emptied into collection vehicleDoor-to-door collection servicePiping system on street/block levelAutomatic (collection service)Small diameter pipes from households to a large collection tankSmall bore sewerage (small diameter sewers laid at shallow gradients to convey sewage)Overview of logistics chain with primary and secondary collection

The general logistics chain is the same for urine and faeces, although the handling method and type of vehicles might be different for the two excreta types (Slob (2005), p. 47)Each point of the logistics chain (numbers 1 to 8 above) has to be designed and costed to make a cost estimate of the transport systemCourse 2 Unit 3Factors affecting vehicle selectionHousing densityWaste generation per household per periodWaste densityHaul distanceRoad surface (muddy, sandy, stony, firm)Road widthsRoad gradientAvailability of spare parts and service

Traffic type and densityWaste corrosiveness and abrasivenessWaste hazardousnessLabour and fuel costAvailable capitalStrength of user in case propulsion is (partly) manuallyRisk of theft, damage and abuseSlob (2005), p. 48Steps to design a transport systemIdentify own situation (source, destination, roads, toilet system)Adapt general criteria for the transport system to own situationIdentify possible vehicle and handling optionsOrganise group meetings with inhabitants, excreta and solid waste collectors and farmersAssess remaining options on the criteria of step 2 and conclude which vehicles and equipment are the most suitableCalculate the costs of the most suitable options as a result of step 5Make a suitable designSource: Slob (2005)Collection and transport options for urinePouring the household containers into a collection container on a small vehiclePumping the urine with a hand pump from the household container into a collection container on small vehicleUsing a centrifugal pump mounted on a tractor-driven trailer with a plastic tank on it (see next slide)Discarded options: Using a vacuum pump mounted on a tractor driven trailer with a vacuum tank too expensiveUsing gravity by constructing the containers at a high level too visibleSwitching the full household container for an empty one and emptying them at a transfer station double handling and transport, and cleaning of containers required

Slob (2005), p. 80

Square plastic tank for urine which could be fixed onto the trailer (Slob (2006, p. 81)Generator to operate a pump (Slob (2005), p. 81)Tractor with trailer to transport urine (in tanks) or faeces (Slob (2005), p. 81)Vacuum pumps or centrifugal pumps?A vacuum pump is the standard to pump a slurry (a vacuum pump can handle the viscosity of the slurry and solid particles, making it a robust pump)A vacuum tank construction needs thick sheets of steel to be able to hold the vacuum build-up in the tankSince urine is a liquid like water, it does not need an expensive vacuuum construction to pump itA centrifugal pump with a plastic tank will be sufficient and cheaper

Hand pump (semi-rotary pump): small and light, seuction depth of 5 m and capacity of 25 50 L/min. (Slob (2005), p. 79)Course 2 Unit 3

Collection vehicle of solid waste collector: Tricycle without engine (Slob (2005), p. 56)

Tricyle with engine (Slob (2005), p. 79)

Tricyle with closed body to keep faeces out of sight and to prevent material from falling on the ground

Course 2 Unit 3Calculations for urine transportThe following equations are set up for urine transport in generalThe numbers used in the example are from Slob (2005), p. 89 for urine transport from 8,000 households with tricycles with engine (no flush water added)Calculation of number of vehicles required for urine transportDecide on work day factor (e.g. 1.17, see Table 1 on next slide)Calculate urine quantity to be collected Eqn. (1)Decide on capacity of collection vehicle (e.g. 300 L, see Table 1)Decide on days between collection events (e.g. 14 days)Calculate the number of households covered in one trip (e.g. 3.5 Eqn. (2))Calculate duration of one trip (e.g. 49 min., see Table 2)Calculate number of trips possible per day (e.g. 8.6) Eqn. (3)Decide on efficiency factor (e.g. 1.25, see Table 1)Calculate the number of trips needed per day (e.g. 192) Eqn. (4)Calculate number of vehicles required (with the numbers above, the result is: 28) Eqn. (6)Go back to step 3 and 4 and change design figures to check if better solution my be found (iterative procedure)

Table 1: Design parameters (Values from Slob (2005), p. 88 89)ParameterValue (example)CommentsWork day factor1.17(= 7/6)Collection service operates six days out of sevenEfficiency factor1.25 (=100/80)Efficiency factor of 80% is assumed to allow for breakdowns and maintenance; number of vehicles is multiplied with 100/80Effective work time7 hours/dayAssume a workday of 8 hours but allow 1 hour for breaksCapacity of collection vehicleTricyle without engine: 100 LTricycle with engine: 300 LTractor with trailer: 3000 LSize of common trailer for tractor: 1.5 m wide and 2.5 m longIn rainy season, the capacity of vehicles may be reducedQuantity to be collected per householdVurine, HH = Npeople, HH purine tcollection

Vurine, HHCollection quantity per household (L/HH) in this example the value is 86 L/HHNpeople, HHNumber of people in household, e.g. 5purine

Urine production per person per day (see Course 1 Unit 2; e.g. 1.23 L/cap/d)tcollection

Time between collection events, e.g. 14 dEqn. (1)Number of households covered in one tripNHH, trip = Vvehicle / Vurine, HH

NHH, tripNumber of households covered in one trip (in this example the number is 3.5)VvehicleCapacity of transport vehicle, e.g. 300 LVurine, HHCollection quantity per household (L/HH) in this example the value is 86 L/HHCourse 2 Unit 3Eqn. (2)Table 2: Total duration of one tripActivityExample (minutes)Driving to first house10Handling per house and driving to next house12(4 houses x 3 min.)Total filling time of tank (= 300 L and 25 L per minute)12Driving to transfer point10Unloading5Total durating of one trip (ttrip)49Slob (2005), p. 89Calculated from equation on previous slide for NHH, tripNumber of trips possible per dayftrips, poss = Nhours ttrip

ftrips, possNumber of trips possible per day (in this example the number is 8.6)NhoursWorking hours per day, e.g. 7 h/dttripDuration of one trip, e.g. 49 min. = 0.82 hEqn. (3)Trips needed per dayftrips, needed = Qurine / VvehicleQurine = Npeople, HH purine fWD NHH

ftrips, neededNumber of trips needed per day (in this example the number is 192 trips/day)QurineQuantity of urine to be collected per day (including work day factor) in this example, the number is 57,400 L/dVvehicleCapacity of the vehicle, e.g. 300 LNpeople, HHNumber of people per household, e.g. 5PurineUrine production per capita per day, e.g. 1.23 L/cap/dFWDWork day factor, e.g. 1.17 (see Table 1)NHHNumber of housholds covered in the scheme, e.g. 8000Eqn. (4)

Eqn. (5)Number of vehicles neededNveh., needed = ftrips, needed / ftrips, poss h

Nveh., neededNumber of vehicles needed (including efficiency factor) in this example, the number is 28ftrips, neededNumber of trips needed per day, e.g. 192 trips per dayftrips, possNumber of trips possible per day, e.g. 8.6 trips per dayhEfficiency factor, e.g. 1.25 (see Table 1)Course 2 Unit 3Eqn. (6)Concluding remarksA worked example (using the same numbers as here) for urine transport is given on page 89 of Slob (2005)

The equivalent calculation can be made for faeces transport (using the mass of faeces instead of volume, e.g. 50 kg/cap/year of faeces)

Only 2.4 vehicles (tricycle with engine) would be needed for the faeces, see p. 121 of Slob (2005)Example figures showing impact of flush waterSome households in this case study area were insisting that flush water should be added after urinationThis would increase the volume to be transported considerably Urine volumes per household (5 people per household, 1.23 L/cap/d, assuming 3 urination events per day):

Urine storage emptying frequencyNo flush water added liter flush water added after urination daily6 litres14 litres weekly43 litres96 litres every 2 weeks86 litres191 litresExample result for number of vehicles required for faeces transport comparing three different options

Example result: size of storage container and number of vehicles versus emptying time period

Size of storage container# Vehicles requiredCourse 2 Unit 3ReferencesHeeb, J., Jenssen, P., Gnanakan, K. & K. Conradin (2007): ecosan curriculum 2.0. In cooperation with: Norwegian University of Life Sciences, ACTS Bangalore, Swiss Agency for Development and Cooperation, German Agency for Technical Cooperation and the International Ecological Engineering Society. Partially available from www.seecon.ch and http://www2.gtz.de/dokumente/oe44/ecosan/cb/en-m23-ecosan-human-dignity-lecture-2006.ppt

Kvarnstrm, E., Emilsson, K., Richert Stintzing, A., Johansson, M., Jnsson, H., af Petersens, E., Schnning, C., Christensen, J., Hellstrm, D., Qvarnstrm, L., Ridderstolpe, P., and Drangert, J.-O. (2006) Urine diversion: One step towards sustainable sanitation, Report 2006-1, EcoSanRes Programme, Stockholm Environment Institute, Stockholm, Sweden. - of relevance here is in particular Appendix 2. Available: http://www.ecosanres.org/pdf_files/Urine_Diversion_2006-1.pdf (also under extra reading)

Slob, M. (2005) Logistic aspects of ecological sanitation in urban areas. Case study in low-income community in Delhi, India. MSc Thesis, University of Twente, The Netherlands and WASTE, Gouda (mariekslob@hotmail.com) (also under extra reading)

Grafiek33.80.52.40.502.2

TricyclesTractorsNumber of vehicles per option

Blad1Tricycle zonder motorTricycle met motorTractorTricycles58230Tractors666Tricycle zonder motorTricycle met motorTractorTricycles140550Tractors141417Tricycle without motorTricycle with motorTractorTricycles3.82.40.0Tractors0.50.52.2

Blad1000000

TricyclesTractorsGunstigste scenario - Aantal voertuigen per optie

Blad2

TricyclesTractorsOngunstigste scenario - Aantal voertuigen per optie

Blad3

TricyclesTractorsNumber of vehicles

Grafiek3501055050.2510033.1251502820026.2525024.530024.535024.5

Size of storagecontainer# Vehicles requiredCollection frequency (days)Size of storage container (litre)# Vechicles required

Prim - NoConNoWaterTable Overview analysis number of tricycles required to cover a certain number of households: Tricycle Primary collection - Scenario: No connection + No water added1. Quantity to collectValueUnitRemarksNumber of households8000HouseholdsGeneration per person per day1.2Litre= 450 litre per person / 365 days per yearAverage household size5Persons2. Analysis frequency of collectionValueUnitRemarksCapacity collection vehicle300LitreCollection frequency (every # days)14DaysAverage collection quantity per household86Litre= Household size x Generation per person per day x Collection frequency3. Analysis number of vehicles neededValueUnitRemarks# Households covered in one trip (Average)3.5Households= Capacity vehicle / Collection quantity per household# Working days between two collection moments12Days= 6 work days per week = (Collection frequency / 7) * 6# Trips needed per day192Trips per day= # Households / # Households covered in one trip / # Working days between 2 collection moments# Trips possible per day8.6Trips per day= See for calculation Annex # Vehicles needed22.4Vehicles= # Trips needed per day / # Trips possible per dayNumber of trips possible per dayMinutesDriving to first house10Handling per house + driving to next house121000 3 minFilling of tank12Driving to transfer point10Unloading5Total time 1 trip takes490.3469387755Collection frequencySize of storagecontainer# Vehicles requiredWorking day 7 hours420To allow for breaks150105.0Nos trips possible8.635050.3710033.11415028.0Collection frequencyQuantity per householdStorage container# Houses per trip# Trips per day# Vehicles needed2120026.3165048.72.384.02825024.53185016.24.840.23530024.57431007.07.226.54235024.514861503.58.622.4211292002.39.121.0281732501.79.819.6352163001.49.819.6422593501.29.819.6

Prim - NoConNoWater0000000000000000

Size of storagecontainer# Vehicles requiredCollection frequencySize of storage container (litre)# Vehicles requiredFig 1 Trade-off for collection frequency: size of storage container and number of vehicles required

Prim - NoConWaterAddTable Overview analysis number of tricycles required to cover a certain number of households: Tricycle Primary collection - Scenario: No connection + Water added1. Quantity to collectValueUnitRemarksNumber of households8000HouseholdsGeneration per person per day2.7Litre= 450 litre per person / 365 days per year + 0,5 litre * 3 times per dayAverage household size5Persons2. Analysis frequency of collectionValueUnitRemarksCapacity collection vehicle300LitreCollection frequency (every # days)14DaysAverage collection quantity per household191Litre= Household size x Generation per person per day x Collection frequency3. Analysis number of vehicles neededValueUnitRemarks# Households covered in one trip (Average)1.6Households= Capacity vehicle / Collection quantity per household# Working days between two collection moments12Days= 6 work days per week = (Collection frequency / 7) * 6# Trips needed per day425Trips per day= # Households / # Households covered in one trip / # Working days between 2 collection moments# Trips possible per day9.8Trips per day= See for calculation Appendix # Vehicles needed43.5Vehicles= # Trips needed per day / # Trips possible per dayNumber of trips possible per dayMinutesDriving to first house10Driving to next house + handling per house61000 3 minFilling speed12Driving to transferpoint10Unloading5Total time 1 trip takes43Working day 7 hours420Nos trips possible9.8Collection frequencyQuantity per householdStorage container# Houses per trip# Trips per day# Vehicles needed1145022.04.1104.33411007.36.961.77962003.18.649.6141913001.69.843.5212874001.09.843.5

Prim - ConNoWaterTable Overview analysis number of tricycles required to cover a certain number of households: Case: Tricycle Primary collection - Scenario: Connection + No water added1. Quantity to collectValueUnitRemarksTable Results Tricycle - Primary collection: Number of tricycles required for different participation levels and scenariosNumber of households8000Households# House-holdsNo ConnectionNo Water AddedNo ConnectionWater AddedConnectionNo Water AddedConnectionWater AddedGeneration per person per day1.2Litre= 450 litre per person / 365 days per yearFreq. 14 daysContainer 150 litreFreq. 14 daysContainer 300 litreNot applicableNot applicableAverage household size5Persons5001.52.81.12. Analysis frequency of collectionValueUnitRemarks10002.85.42.3Capacity collection vehicle300Litre15004.28.23.4Collection frequency (every # days)14Days20005.610.94.6Average collection quantity per household86Litre= Household size x Generation per person per day x Collection frequency25007.013.65.730008.416.36.83. Analysis number of vehicles neededValueUnitRemarks35009.819.08.0# Households covered in one trip (Average)3.5Households= Capacity vehicle / Collection quantity per household400011.221.89.1# Working days between two collection moments12Days= 6 work days per week = (Collection frequency / 7) * 6450012.624.510.3# Trips needed per day192Trips per day= # Households / # Households covered in one trip / # Working days between 2 collection moments500014.027.211.4# Trips possible per day10.5Trips per day= See for calculation Appendix 550015.429.912.6# Vehicles needed18.3Vehicles= # Trips needed per day / # Trips possible per day600016.832.613.7650018.235.414.8Number of trips possible per dayMinutes700019.638.116.0Driving to first house10750021.040.817.1Driving to next house + handling per house3800022.443.518.3Filling speed12Driving to transferpoint10Table Results Tricycle - Primary collection: Number of tricycles required for different participation levels and scenariosUnloading5# House-holdsNo ConnectionNo Water AddedNo ConnectionWater AddedConnectionNo Water AddedConnectionWater AddedTotal time 1 trip takes40Freq. 14 daysContainer 150 litreFreq. 14 daysContainer 300 litreNot applicableNot applicableWorking day 7 hours4201000.30.60.2Nos trips possible10.52000.61.10.53000.91.70.74001.22.30.9Collection frequencyQuantity per householdStorage container# Houses per connection# Trips per day# Vehicles needed5001.52.81.1165048.710.518.36001.83.41.43185016.210.518.37002.14.01.67431007.010.518.38002.44.61.814861503.510.518.39002.75.12.1211292002.310.518.310002.85.42.3281732501.710.518.3352163001.410.518.3422593501.210.518.3

Prim - ConWaterAddTable Overview analysis number of tricycles required to cover a certain number of households: Tricycle Primary collection - Scenario: Connection + Water added1. Quantity to collectValueUnitRemarksTable Results Tricycle - Primary collection: Number of tricycles required for different participation levels and scenariosNumber of households1000Households# House-holdsNo ConnectionNo Water AddedNo ConnectionWater AddedConnectionNo Water AddedConnectionWater AddedGeneration per person per day2.7Litre= 450 litre per person / 365 days per year + 0,5 litre * 3 times per dayFreq. 14 daysContainer 150 litreFreq. 14 daysContainer 300 litreNot applicableNot applicableAverage household size5Persons5001.52.81.12.52. Analysis frequency of collectionValueUnitRemarks10002.85.42.35.1Capacity collection vehicle300Litre15004.28.23.47.6Collection frequency (every # days)14Days20005.610.94.610.1Average collection quantity per household191Litre= Household size x Generation per person per day x Collection frequency25007.013.65.712.730008.416.36.815.23. Analysis number of vehicles neededValueUnitRemarks35009.819.08.017.7# Households covered in one trip (Average)1.6Households= Capacity vehicle / Collection quantity per household400011.221.89.120.2# Working days between two collection moments12Days= 6 work days per week = (Collection frequency / 7) * 6450012.624.510.322.8# Trips needed per day53Trips per day= # Households / # Households covered in one trip / # Working days between 2 collection moments500014.027.211.425.3# Trips possible per day10.5Trips per day= See for calculation Appendix 550015.429.912.627.8# Vehicles needed5.1Vehicles= # Trips needed per day / # Trips possible per day600016.832.613.730.4650018.235.414.832.9Number of trips possible per dayMinutes700019.638.116.035.4Driving to first house10750021.040.817.138.0Driving to next house + handling per house3800022.443.518.340.5Filling speed12Driving to transferpoint10Table Results Tricycle - Primary collection: Number of tricycles required for different participation levels and scenariosUnloading5# House-holdsNo ConnectionNo Water AddedNo ConnectionWater AddedConnectionNo Water AddedConnectionWater AddedTotal time 1 trip takes40Freq. 14 daysContainer 150 litreFreq. 14 daysContainer 300 litreNot applicableNot applicableWorking day 7 hours4201000.30.60.20.5Nos trips possible10.52000.61.10.51.03000.91.70.71.54001.22.30.92.0Collection frequencyQuantity per householdStorage container# Houses per connection# Trips per day# Vehicles needed5001.52.81.12.51145022.010.540.56001.83.41.43.03411007.310.540.57002.14.01.63.57962003.110.540.58002.44.61.84.0141913001.610.540.59002.75.12.14.6212874001.010.540.510002.85.42.35.1

Secondary CollTable Analysis number of tractors required to cover a certain number of households: Tricycle - Secondary collection - Scenario: No water addedTable Analysis number of tractors required to cover a certain number of households:1. Quantity collected per dayValueUnitRemarksTricycle - Secondary collection - Scenario: No water addedNumber of households8000HouseholdsHouseholdsNo Water AddedWater AddedGeneration per person per day2.7Litre= 450 litre per person / 365 days per year1000.10.1Average household size5Persons2000.10.3Quantity collected per day109315Litre3000.20.44000.20.52. Analysis frequency of collectionValueUnitRemarks5000.30.7Capacity collection vehicle3000Litre6000.40.8Conversion to workday0.8571428571Days= 6 work days per week = (1/7) * 67000.41.0# Trips needed per day42.5Trips per day= Quantity collected per day / Capacity collection vehicle / Conversion to workday8000.51.1# Trips possible per day3.9Trips per day= See for calculation Appendix 9000.61.2# Vehicles needed10.9Vehicles= # Trips needed per day / # Trips possible per day10000.61.4Number of trips possible per dayMinutesTable Analysis number of tractors required to cover a certain number of households: Tricycle - Secondary collection - Scenario: No water addedHandling at transfer station4Filling of tank12HouseholdsNo Water AddedWater AddedDriving to farmers405000.30.7Unloading1210000.61.4Returning to Saboli4015000.92.0Total time 1 trip takes10820001.22.725001.53.4Working day 7 hours42030001.84.1Nos trips possible3.935002.24.840002.55.575 households 1 keer in de week naar boeren45002.86.1Vanaf 400 households participating, elke dag 1 keer naar farmers50003.16.88000 households 4 tractors af en aan rijden55003.47.560003.78.265004.08.970004.39.675004.610.280004.910.9

OverviewTable Number of tricycles required for different participation levelsTricycle - Primary collection# House-holdsNo ConnectionNo Water AddedNo ConnectionWater AddedConnectionNo Water AddedConnectionWater AddedTable Number of tractors required for different participation levelsTricycle - Secondary collectionFreq. 14 daysContainer 150 litreFreq. 14 daysContainer 300 litreNot applicableNot applicableHouseholdsNo Water AddedWater Added5001.52.81.12.55000.30.710002.85.42.35.110000.61.415004.28.23.47.615000.92.020005.610.94.610.120001.22.725007.013.65.712.725001.53.430008.416.36.815.230001.84.135009.819.08.017.735002.24.8400011.221.89.120.240002.55.5450012.624.510.322.845002.86.1500014.027.211.425.350003.16.8550015.429.912.627.855003.47.5600016.832.613.730.460003.78.2650018.235.414.832.965004.08.9700019.638.116.035.470004.39.6750021.040.817.138.075004.610.2800022.443.518.340.580004.910.9Table Number of tricycles required for different participation levelsTricycle - Primary collection# House-holdsNo ConnectionNo Water AddedNo ConnectionWater AddedConnectionNo Water AddedConnectionWater AddedTable Number of tractors required for different participation levelsFreq. 14 daysContainer 150 litreFreq. 14 daysContainer 300 litreNot applicableNot applicableTricycle - Secondary collectionHouseholdsNo Water AddedWater Added1000.30.60.20.51000.10.12000.61.10.51.02000.10.33000.91.70.71.53000.20.44001.22.30.92.04000.20.55001.52.81.12.55000.30.76001.83.41.43.06000.40.87002.14.01.63.57000.41.08002.44.61.84.08000.51.19002.75.12.14.69000.61.210002.85.42.35.110000.61.4

Transfer station(Un)loading time (min)It is likely that the present sweepers will find handpumps difficult to work with at first and it may take some time for them to develop the arm muscles rquired for the continuous moving of the handle.Tricycle5Load capacityTractor16Blz 63 preventive maintenanceCalculation capacity of transfer stationTotal available time (minutes)480= 8 hours a dayService factor80%The workload should be reduced to 80% to prevent long queus to emerge for the incoming vehicles (refer to queqing theory)Total available time including service factor (minutes)384(Un)loading time for 1 tractor load + 10 tricycles loads25For each tractor load 10 tricycles loads have to be deposited. It is assumped two tricycles together with one tractor can (un)load at the same timeCapacity for # 1 tractor loads - 10 tricycle loads15.4Calculation of number of loads for 8000 householdsNo water addedWater addedQuantity per day generated49315109315= 8000 Households * 5 persons per household * Amount of urine + water per personQuantity per day to process57534127534Conversion to 6 workdays a week# Tricycles loads to transfer192425= Quantity per day to process / 300 litre (load capacity)# Tractors loads to transfer1943= Quantity per day to process / 3000 litre (load capacity)Number of transfer stations needed1.32.8Divided by 15 (Capacity for # 1 tractor loads - 10 tricycle loads)2-3 nodig

CostsInvestment costsAssumptionsTricycle with engine12,000New tricycle with second hand engineTank plastic 300 litre1,0503,5 rs per litre (Best quality plastic)Hand pump2,000Hose250Total investment costs per vehicle15,300Yearly capital costsAssumptionsTricycleTractorTransfer stationUnit price15,300Investment costs per vehicle/station15,300111,20042,000Depreciation3,0605 years economic lifetimeInterest on capital1,83612% per yearYearly Capital costs4,8963%24,46410%9,24035%Total capital costs per vehicle4,896Yearly Operational and maintenance costs103,36066%165,93570%17,08565%Yearly Labour costs48,00031%48,00020%00%Yearly operational costsAssumptionsTotal yearly costs per vehicle/station156,256100%238,399100%26,325100%Petrol tricycle100,1602 litre/hr for 4 hr/day (60% drive-time in 7 hrs) a 40 rs/litre for 313 days/yearMaintenance cost tricycle2,500Which comes to 20% of investment costsMaintenance cost pump / hose700Total O&M costs per vehicle103,360Yearly labour costsAssumptionsOne operator48,000(4000 rp/month x 12 months)Costs per vehicle per year156,256Efficiency factor1.25An overall efficiency of 80% is assumed to allow for inefficiencies due to breakdown, maintenance and the number of trips madeVermenigvuldigen met required number of vehiclesInvestment costs most basic transfer stationTank plastic 6000 litre21,0003,5 rs per litre (Best quality plastic). Tank of 5000 litre is chosen to allow for some overcapacity to allow the tricycles to be able continously unload in case the tractor is delayedGenerator set with build in centrifugal pump10,000To load the tractor trolleyHoses1,000Construction costs + handpump10,000In most basic form construction is only digging a hole in the ground to fit the tank in and installation of handpump.Total investment costs42,000Yearly capital costsAssumptionsUnit price42,000Depreciation4,20010 years economic lifetimeInterest on capital5,04012% per yearTotal capital costs per station9,240Yearly operational costsAssumptionsKerosine genset14,0853 ltr/day a 15 rp/ltr x 313 days/yearMaintenance cost genset and handpump2,000Maintenance cost hoses1,000Total O&M costs per station17,085Yearly labour costsAssumptions-Costs per station per year26,325money should be reserved for reinforcing the area and access road in a later stage.Supervisor to supervise and keep the area cleanReenforced transfer area and access road, water supply and small officeMaintenance transfer areaFor tractor nu geen genset nodigInvestment costsAssumptionsTractor75,000Second handTrolley25,000Second handPlastic tank 3000 litre10,5003,5 rs per litre (Best quality plastic)Suction hose70070 rs per metre (Good quality)Total investment costs111,200Yearly capital costsAssumptionsUnit price111,200Depreciation11,12010 years economic lifetimeInterest on capital13,34412% per yearTotal capital costs per vehicle24,464Yearly operational costsAssumptionsDiesel tractor154,9353 litre/hr for 5,5 hr/day (80% drive-time in 7 hrs) a 30 rs/litre for 313 days/yearMaintenance cost tractor11,000Which comes to 10% of investment costsTotal O&M costs per vehicle165,935Yearly labour costsAssumptionsOne driver48,000(4000 rp/month x 12 months)Costs per vehicle per year238,399

Blad2Table 6 Overview Investment and yearly costs per vehicleOption Primary collection with tricycleTricycle without engineTricycle with engineTractorTransfer stationInvestment costs per vehicle/station8,60015,300111,20042,000Yearly Capital costs2,7525%4,8963%24,46410%9,24035%Yearly Operational and maintenance costs2,2004%103,36066%165,93570%17,08565%Yearly Labour costs48,00091%48,00031%48,00020%00%Total yearly costs per vehicle/station52,952100%156,256100%238,399100%26,325100%Option Primary collection by tractor - Direct transportTractorInvestment costs121,200Yearly Capital costs26,66411%Yearly Operational and maintenance costs176,32570%Yearly Labour costs48,00019%Total yearly costs250,989100%