tecnologías y conceptos para saneamiento decentralizado · pdf filelatinamerica....

Dr. Claudia Pabón PereiraLeAF - Lettinga Associates Foundation

Wageningen, The Netherlands

con contribuciones de : Dr. Adriaan Mels, Dr.Katarzyna Kujawa-Roeleveld, Dr. Grietje Zeeman y Claudia Agudelo, MSc

Tecnologías y conceptos para saneamiento decentralizado y valorización de recursos

Estudios de caso SWITCH

Lettinga Associates Foundation

for Environmental Protection & Resource Conservation



1. Experiencias Switch en tecnologías y manejo para tratamiento y reutilización de aguas grises

2. Proceso anaeróbico de tratamiento de residuos sólidos sanitarios con aprovechamiento de biogás

3. Tecnologías para recolectar, transportar, tratar y disponer los productos de saneamiento seco (objetivos, criterios, indicadores, toma de decisiones)

Tematicas a cubrir





• Action research Programme implemented and co-funded by the European Union and a cross-disciplinary team of 33 partners from 15 countries around the world

• The SWITCH Consortium represents academics, urban planners, water utilities and consultants. This network of researchers and practitioners work directly with civil society through 'learning alliances' in ten global cities.

SWITCH ProjectManaging water in the city of the future





• Stormwatermanagement

• Efficient use of water

• Closing loop systems

• Governance• Sharing knowledge






Urban ecohydrology

Source: Zalewski, Wagner, (2008)





• Belo horizonte (Brazil): • Urban drainage and

stormwater management• Cali (Colombia):

• Improve water quality in Cauca River

• Focus in new settlements• Tegucigalpa (Honduras)

• Drinking water provision in areas with difficult access

SWITCHLatinamerica





Lima:• Problem Statement:

• 8 million people• 90% drinking water• 85% sewer• Only 15% ww is treated

• 2600 ha urban and periurbanagriculture

• Waster reused with ad withouttreatment

• Potential demand 5500 ha

SWITCHPeru





• Lima-Switch project• Wastewater treatment

and reuse in urbanagriculture and greenareas

• Inventarization of 37 cases

• Emphasis in decisionmaking processes and learning alliances

• ETC, TUHH

SWITCHPeru





Learning Alliances





• OGAPU Project• To help combat urban poverty,

improve food security and foster public participation at the local level through the implementation of a wastewater treatment system for re-use in multi-functional green areas

• 1 l/s wastewater• 2,6 ha de recreative and

agricultural use

• IPES, Ministry of Environment, municipalidad VES

SWITCHPeru

Demonstrative Project Villa El Salvador





www.switchurbanwater.eu

Documents, presentationsTraining material

Resources

Dr. Claudia Pabón Pereira, PhDLeAF - Lettinga Associates Foundation


Sesión 1.Enfoque y experiencias Switch en tecnologías y manejo de aguas grises





Decentralized sanitation

Urine

GreywaterStorm water

Flusing and cleansing water

Faeces





Main characteristics of sanitation flows

� Urine

• 500 L/p/yr

• 2-4 kg Nitrogen

• Free of pathogens

� Faeces

• 50 L/p/yr

• Few nutrients

• Most pathogens

� Greywater:

• ~35.000 L/p/yr (95 L/p/d)-NL

• Few nutrients(10-20% N-BW)

• Few pathogens

� Rainwater:

• Depends on rainfall

• No nutrients

• Other pollutants





Composition of household (waste)water

30%

30%

6%

34%COD

9%10%

70%

11%

N

P 46%

8% 23%

23%

Fae

ces

Gre

y w

ater

Urin

eK

itche

n w

aste





� Grey water (2/3 of total wastewater) is relatively clean and can be treated locally

� Treated water can be used for ground water recharge, local water systems (attractive urban environment) or irrigation

� Several treatment options: e.g. constructed wetlands, biorotors, membrane bioreactors

Grey water treatment





Drawbacks of man-made infrastructure for urban water management

• High costs• Skilled personnel required for operation

and maintenance• Potential risk of flooding and pollution• Loss of biodiversity and amenities• Carbon emissions





A more sustainable approach

Alternatives to the conventional approach using natural systems:

• Characterized by the use of naturally occurring energies such as solar and wind energy, as opposed to fossil fuels and chemicals in conventional treatments.





Natural systems and the urban water cycle

Water supply

Wastewater management

Stormwater management





Natural systems and sustainable urban development

EcosystemsEnvironmental amenities

Local economic development

Health





• It can save costs for centralised sewer systems

• Adaptability to different environments and local conditions

• May provide a non-conventional source of water for landscape irrigation, toilet flushing, etc.

• May form an attractive element in urban landscaping, especially in water-scarce areas

Advantages of wetlands





• Area required (10 times bigger than activated sludge)• ‘Build and forget’ approach• Winter operation is often questioned• Faulty pretreatment• Clogging of the upper layers of the wetland • Incorrect perception that grey water is innocuous. • In order to safeguard public health, continuous

process verification, plumbing management and customer education are therefore needed.

Challenges for natural systems





• In rural areas not many barriers are present• In urban areas conventional systems are still

preferred because of : a) Convenience for the final users b) Complexity in organization: involvement of many

actors, project developers or housing corporations, future inhabitants, the local municipality, water authorities and water utility companies.

c) Sewer systems already exist and investments in assets have already been made

Challenges natural systems





• Commonly used plants :

a) Helophytes like reed or cattail. b) SF systems:

i. Free floating macrophytes like duckweed or water hyacinth,

ii. floating-leaved bottom-rooted macrophytes like lotus or submersed macrophytes like waterweed.

Wetland systems





• Exploit the biogeochemical cycles that occur in natural wetland ecosystems for the purpose of wastewater treatment

• Enhancement by means of directing flows, oxygenation, materials and plant species used

Advantages





Horizontal Subsurface Flow Constructed Wetland

Free-Water Surface Constructed Wetland

Vertical Flow Constructed Wetland

Types of Constructed Wetland systems





• CWs not only function as stand-alone treatment plants but can be combined with other CWs or with other low-tech or high-tech wastewater system

• The climatic conditions, the size and design of the wetlands, the loading rates and regime, the plant species composition, and the type and composition of the wastewater vary considerably between sites

• Removal percentages are mainly dependent on temperature, hydraulic residence time (HRT) and loading rate

Design and role of CW





Experiencias internacionales Switch en tratamientode aguas grises

• Beijing• Holanda, Alemania y Suecia• GhanaOther experiences• Peru• Filipinas• Colombia• Espana• Wetland modeling





Beijing, ChinaDecentralized wastewater reclamation systems in Beijing

Adoption and performance under field conditions

Adriaan Mels, ShujiGuo, Chang Zhang, Xiangbin Li, Haoran Wang, ShengheLiu and Okke Braadbaart





Beijinga) Capital and political centre of PR China b) 16,808 square kilometres c) Land climate; -20 to +40 ℃d) Precipitation 585 mm; evaporation > 1500 mm per year





A rapidly growing city

02468

101214161820

1960 1970 1980 1990 2000 2010 2020 2030

Time

Pop

ulat

ion

(in m

illio

ns)

Source: Bureau of Statistics of Beijing Municipality





… a very water scarce city

� Current water availability is < 300 m3 per capita per year� Severe overexploitation groundwater� The shortfall between water supply and demand is estimated to

be around 1.8 billion cubic meters by 2010





Measures for alleviating water scarcity in Beijing

� Water saving (410 million cubic meters is planned for 2010)

� South-to-north water diversion project (1.2 billion cubic meters yearly)

� Rain water harvest (150 million cubic meters)

� Wastewater reclamation (640 million cubic meters)

source: Wei et al,2005





Wastewater reuse planningCurrent situation of wastewater reclamation systems in urban Beijing (note: this does not include wastewater reuse for agricultural irrigation and industrial reuse):

� four centralized wastewater treatment plants for reclamation with total treatment capacity of 255,000 m3/day.

� 4000 km pipeline to redistribute the reclaimed water� 300 - 400 decentralized wastewater reclamation

systems with treatment capacity of 50,000 – 60,000 m3/day

source: Water Saving Office,2006 - 2008

Dr. Claudia Pabón Pereira, PhDLeAF - Lettinga Associates Foundation


Sesion 1.Experiencias Switch en tecnologías y manejo para tratamiento y reutilización de aguas grises





Wastewater reuse planning

Figure 1. Wastewater reuse planning for the Beijing central region (source: Jia et al., 2005)





‘Management regulation on the construction of wastewater reclamation facilities in Beijing’ (1987)

In this regulation the Beijing Municipal Government issued that:

� hotels with construction areas exceeding 20,000 m2

and

� all public buildings with construction areas exceeding 30,000 m2 should build a decentralized reclamation facility.

� As of 2001 also new residential areas exceeding 50,000 m2 fall under this regulation

Five cases presented (of 9 investigated)

BOBO Garden House Residential Area

Beijing Jiaotong University

Xin Bei Wei Hotel

Beiluchun Residential Area Beijing Normal University





• Reclaimed water use:� Toilet water, road cleaning, landscape

irrigation, car washing, construction, fire fighting

Decentralized Wastewater Reclamation System

PI 1 Technical performance

System monitoring Electricity consumption (kWh/m3)

Compliance with effluent standards Time input for O&M

Effluent use Yearly failures (frequency and down time)

PI 2 Financial performance

Investment cost (RMB) Pay back time

O&M costs (RMB / m3)

PI 3 Public health and safety

Effluent quality in relation to use purpose

System accessible for unauthorized personnel

Illness records Health and safety of operators

PI 4 Invisibility and user comfort

Odor events / complaints Invisibility of system (& aesthetics)

Noise Space requirement

PI 5 Social acceptability Awareness of users Willingness to pay

Satisfaction on the use of reclaimed water

Performance Indicators (PIs)





Technology selection tool (under development)

0

0.5

1PI 2 Financial performance

PI 1 Technical performance

PI 3 Public health and safetyPI 4 Invisibility and user comfort

PI 5 Social aw areness System A

System B

System C

Beijing Rainbow Hotel (max. 120 m3 / day)

Buffer tank

Item Beijing Jiaotong

University

Beiluchun Residential

area

Beijing Normal

University

Xin Bei Wei Hotel

BOBO Garden House

Residential area

Established in 1993 1999 2001 2002 2003 Influent source Grey

wastewater Mixed

wastewater Mixed

wastewater Grey

wastewater Mixed

wastewater Main treatment technology

Activated sludge

Aerated Ceramic

Filter Activated

sludge

Contact oxidation + disinfection

Contact oxidation + Activated

sludge

Maximal reclamation capacity (m3/day)

200 640 720 120 1,200

Average reclamation (m3/day) 150 600 400 80 3001

Technologies and capacities

1 Another 700 m3 per day are treated and than discharged to the sewer system

Monitoring, operation and maintenance

Question Beijing Jiaotong

University

Beiluchun Beijing Normal

University

Xin Bei Wei Hotel

BOBO Garden House

Is the system being monitored? yes* yes* yes* yes* yes* Compliance with effluent quality standards?

yes yes yes yes yes

Electricity consumption (kWh/m3)? 0.75 0.72 1.00 1.50 1.20 Time input (labour) for operation and maintenance (h / year)

n.a.f.** n.a.f.** Approx.

8760 Approx.

1825 Approx.

1095 What could be the reason causing a failure of the DWRS?

Power cut Power cut

Power cut / pump mal-

function

pump mal-function

*** Power cut

Any reported failures of the system? n.a.f.** n.a.f.** 0 0 0 * monitoring on voluntary basis once per year (no requirement) ** n.a.f. – not asked for, in the first interviews we did not include this question ** * Back-up generator for electricity supply available





Technical performance (final water use)


University

Beiluchun Residential

area

Beijing Normal

University

Xin Bei Wei Hotel

BOBO Garden House

Residential area

Use purposes for the reclaimed water (% of total) - toilet flushing 0% yes2 80% 100% 80% - landscape irrigation 100% yes 20% 0% 15% -street cleaning 0% no 0% 0% 5% - car washing 0% yes 0% 0% 0% - fire water storage 0% yes 0% 0% 0%





Financial performance


University


University

Xin Bei Wei Hotel

BOBO Garden House

Established in 1993 1999 2001 2002 2003

Investment costs for the treatment system (RMB)

300,000 1,400,000 3,400,000 600,000 3,000,000

Operation and maintenance costs (including labor costs) (RMB/m3)

0.75 1.08 1.50 1.13 1.72

Current price of the tap water (RMB/m3)

3.7 3.7 3.7 6.1 3.7

Pay back time (years) 1.9 2.4 10.6* 4.1** 13.8*

* pay back times of 5.1 and 6.3 years at a tap water price of 6.1 RMB / m3 ** pay back time of 8.0 years at a tap water price of 3.7 RMB /m3





Pay back time when using at fullcapacity

0

2

4

6

8

10

0 100 200 300 400 500 600 700 800 900 1000

Capacity of treatment system (m3 / day)

Pay

bac

k tim

e (y

ears

)

Residential price:3.7 RMB / m3

Company price:6.1 RMB / m3

(based on data of Jia et al, 2005)





Awareness of users


University


University

Xin Bei Wei Hotel

BOBO Garden House

Awareness on the use of reclaimed water

0% -- 80% 40% 50%

Wastewater reuse is considered positive (only asked if people were aware(

-- -- yes yes yes

Number of Respondents 10 -- 14 10 10

Beijing Water Authority is the responsible local government organization

Step 1

National

Construction

Ministry/ Local

government

enacts Laws/

regulations/ policy

Step 2

Local water saving

office (Water

Authority)

executes the

policies and

regulations

Step 3

Owners or

investors

communicate and

negotiate integrally

for the plan

Step 5

Local

Environmental

Protection Bureau

examines the

results

Step 4

Environmental

Company or

Construction

Company

implements plan

and construct the

system

Local water saving office (Water Authority)

Explanation of

the policy

Communication

and agreement

Approval of

the

implemenation

Government role

Reclaimed water quality standards (source: General Administration of Quality Supervision, Inspection and Quarantine, 2002)

Road cleaning

No. Parameter Toilet flushing

Fire-fighting

Urban afforestation /

landscape irrigation

Car washing

Construction

1 Color ≤ 30 2 pH 6-9 3 Odor No unpleasant smell 3 Turbidity(NTU) ≤ 5 10 10 5 20 4 Dissolved Solids (mg/l) ≤ 1500 1500 1000 1000 --- 5 BOD5 (mg/l) ≤ 10 15 20 10 15 6 Ammonia nitrogen (mg/l)

≤ 10 10 20 10 20

7 Anion surfactants (mg/l) ≤

1.0 1.0 1.0 0.5 1.0

8 Fe (mg/l) ≤ 0.3 --- --- 0.3 --- 9 Mn (mg/l) ≤ 0.1 --- --- 0.1 --- 10 Dissolved Oxygen (mg/l)> 1 11 Free residual chloride

(mg/l) ≥ 1.0 after 30 minutes contact

≥ 0.2 at the end of pipes 12 Coliform Number/L ≤ 3





Drivers and barriers for implementation

� There is a strong financial driver to implement DWRSs, because of the relatively short pay back times, especially for the private sector.

� Other drivers are related to the regulations and to awareness on water scarcity issues.

� Universities (3) also use it as educational tool

� Barriers are high initial investment costs and uncertainty about water charge (for the residential areas)





Some conclusions� Both mixed and grey wastewater is reclaimed, various

techniques (contact oxidation, activated sludge systems, SBR systems).

� Systems function well although effluent monitoring is done on voluntary basis and real quality control by an independent party is lacking.

� Awareness is moderate to high, and users that are aware see it as positive





Experiences in the use of wetlandsystems for greywater treatment





Holanda, Alemania y NoruegaExperiencias en uso de humedales para

tratamiento de aguas grises

COMPARATIVE PERFORMANCE OF CONSTRUCTED WETLANDS FOR DECENTRALIZED TREATMENT OF

GREY WATER IN THE NETHERLANDS, GERMANY AND NORWAY

Claudia Agudelo, Adriaan Mels, Paul Telkamp, Erwin Koetze, Wouter van Betuw, Joost van den Bulk and Okke Braadbaart





• Analyze the adoption, technical performance and managerial aspects of CW systems in urban areas based on a number of case studies.

• 4 in The Netherlands, 2 in Norway, and 1 in Germany

• Systems built between 1993 and 2000• Households, promoters and operators were

interviewed to investigate their experiences and satisfaction about the systems ormed between 2005 and 2008.

Scope of the study





• Different system configuration:a) different types of toiletsb) pretreatments c) combination with other sources (rainwater)d) separation systems or conventional sewer.

• Settlements from 24 to 110 houses.• Size of the studied wetlands varied

between 22m² and 3000m².

Cases





• Depth : 0.30 m and 1.0 m

• HR: 6-18 days

• CW type:

a) vertical (infiltrating reed bed x3, infiltrating greenhouse , subsurface flow )

b) horizontal flow (reed bed, subsurface x 2)

• area / person (m²/p): 1.88-12.5 (2.5)

• Pretreatment: septic tank, sedimentation tank, aerobic biofilter

• Post-treatment: filters and retention pond

• Reuse: toilet, washing machines, irrigation

• Wetland sludge: removed every 6 months and composted or MWWS

Design and operational characteristics





1. Performance: 4 indicators. � Public health protection� Technical aspects: flexibility, operation and maintenance, failures� Environmental aspects: emissions, recovery of resources� Cost: as compared to conventional systems

2. Technology choice : � drivers and barriers for different actors: governmental

organizations, project developers, and the future inhabitants

3. Institutional aspects & management: � involvement during decision making process, ownership and

responsibilities

Indicators





• Public health protection: health risk low or inexistent• Technical aspects:

a) High buffering capacity: Effluent quality normally quite stableb) High system reliability: failures can be easily avoided by doing

proper maintenancec) Failures: 1 each 10 years, mainly clogging in the wetland due to

inappropriate maintenancei. Maintenance routines are not performed as planned and inappropriate

procedures are followedii. Lack of knowledge in the general maintenance: Inadequate soil

replacement or no replacement at all

d) Additional measures in winter: extra deep pond or disconnectede) 5 cases odor perceived in the summer

Results – Performance (1/3)





• Environmental aspectsa) Removal rates not comparable because of different

influent qualities and designsb) Up to 57% less water consumptionc) Energy consumption relatively low (main item is

recirculation system for water reuse)d) Indirect benefit: users leading to awareness raising-

use of environmental friendly products and control of pollutant discharges






• Costs: more expensive than conventional a) initial investment is higher due to double piping and

pumps required to transport the water to the wetland and if needed to re-circulate the effluent

b) Bad planning: need of back up systems, errors during implementation, early failures, and unforeseen aspects due to lack of experience






• Drivers: Positive environmental feeling, water saving. Reduction of water emissions, protection of surface water, landscape function low maintenance requirement and low operational costs

• Barriers: Decentralized maintenance because of the responsibilities it implies for users, restriction in cleaning products and higher investment cost






0 1 2 3 4 5 6 7 8

Positive feeling about environment

Water saving

Neighbourhood landscaping

Reduction of water emissions

Protection of surface water

Taking responsibility

Improved quality of living

Reduction of energy use

Recycling of water

Collaboration with neighbours

Less dilution of black water

Low maintenance

Prevention of drying out of soil

Drivers

Frequency






0 0.5 1 1.5 2 2.5 3 3.5

Maintenance

Restrictions on products

Economic barriers

Smell

Energy costs (compared to conventional system)

Barriers

Frequency

lack of support by the governmental authorities to reduce the fees

Drivers and Barriers for implementation





• Decentralized systems: diffuse distribution of responsibilities

• Ownership: Collective of house owners or housing companies

• Operation & Maintenance : specialized companies, but also collective responsibility of the neighborhood dwellers

• Main problems : a) unclear responsibilities for O&M leading to inadequate

maintenance, b) higher cost than expected c) no economical benefits such as reduction of sewerage fee

Managerial aspects





EVA Lanxmeer, NL





• P removal is insufficient

Challenges for CW

Treatment results of constructed wetlands

Groningen, Netherlands

(horizontal system)

Luebeck, Germany

(vertical system) Influent Effluent Influent Effluent COD (mg O2/l) 550 45 502 59 BOD (mg O2/l) 298 2 194 14 N-total (mg N/l) 12.6 1.6 12 2.7 NH4-N (mg N/l) 3.8 0.22 4.5 0.9 P-total (mg P/l) 1.8 0.31 8 5.7 PO4-P 0.94 0.23 7.6 4.8





EVA Lanxmeer, NL





EVA Lanxmeer, NL

•32 houses

•Laundry and bathroom (no kitchen)

•1200 m2 near the houses, discharge in the canal





Wetland performance• Turbidity is reduced from 61 to 0,4;• Ammonia is reduced from 5,3 ppm-N to <0,04 ppm N;• BOD is reduced from 116 to <1 ppm O2;• COD is reduced from 267 to 12 ppm O2;• Kjeldahl-N is removed from 10 to 0,3 ppm-N;• The microbial quality is improved but the numbers are

still too high with respect to e.g.drinking water standards;

• Boron and phosphorus are only slightly removed.

EVA Lanxmeer, NL





Constructed wetland for office building





Accra, GhanaGREY WATER TREATMENT USING CONSTRUCTED AND

NATURAL WETLANDS IN GHANASteven Niyonzima, Esi Awuah, Alexander Offei Anakwa





Constructed wetland

• Constructed and operated on the KNUST campus - KwameNkrumah University of Science and Technology

• Sedimentation tank + Horizontal Sub-Surface Flow pilot-scale

• Dimensions:a) Sedimentation tank of dimensions 3.65 x 0.65 x 0.4 m (depth) b) Horizontal Sub-surface constructed wetland of 3.5m x 0.8m x

0.8m (depth). • Filter media: 0.6 to 2 mm of coarse sand• Influent flow rate: 0.48 m3/day • Effluent flow rate : 0. 33 m3/ day • Retention time:15 hours.





Constructed wetland

• The removal efficiency of BOD, COD, SS, grease, and Faecal Coliform : 72-79%

• Nutrients removal : 34% -53%.

• Effluent characteristics did not meet the EPA (Ghana) guidelines

• The organic load of the waste water discharged into the wetland was much more than anticipated

Cattails (Typha latifolia sp)Bioremediation, edible





Natural wetland

• Eight week experiment• Analysis of COD, BOD, Total Coliform, Turbidity,

Suspended Solids, Phosphates, Nitrite-N, Conductivity, Nitrate –N, Mn, Pb, Cu, Fe and Zn

• The soils were sandy loam with the clay portion of less than the ideal distribution for wetland soil of 15%.

• Influent flow rate: 7.16 l/s • Outlet flow rate was 45% of inlet flow rate • the Hydraulic loading rate was 1.4 cm/d• Hydraulic retention time of 3 days was maintained in the

system.





Natural wetland

• Removal efficiencies:a) Turbidity, Suspended Solids, COD, BOD, Total Coliform

ranged between 85-99%; b) Phosphates and Nitrite-N ranged between 70-85% ;c) Conductivity and Nitrate –N were less than 50% ; d) Heavy metals( Mn and Pb) were less than 50%, e) Cu and Fe ranged between 50-70%, f) Zn was 78.8% and Cd was found to have accumulated

in the soils receiving greywater. g) SS removal efficiency best performance: 98.8% removal

• Most of the parameters under study met the EPA (Ghana) guideline values.





Colocasia esculenta (Taro)

Nitrate removal

Xanthosoma sagittifoliumTaioba or Tannia also called

malanga, yautia, ocumo criollo and cocoyam

• The wetland species present in the natural wetland were predominantly Colocasia esculenta, Xanthosoma sp, Thala sp. and Coix lacryma

Coix lacryma.

Ornamental, edible

Natural wetland

Other cases





Lima, PeruASSESSMENT OF THE ECOSAN TECHNOLOGY IN LIMA

(PERU) AND ITS POSSIBLE APPLICATIONSMSC THESIS by LAURA LÓPEZ RAMÍREZ

MSc Urban Environmental ManagementWageningen University





Residual water Latrine

The Case of the NGO’s CENCA and ALTERNATIVA





AREA 1 - CENCA

A pilot project with 55 dry ecological toilets in two human settlements (slums)at the East of Lima, called Los Topacios of Nievería and Casa Huerta laCampiña of Cajamarquilla

AREA 1 - CENCAShower

Men urinal

Pipe to ventilate the composting

chambers Washbasin





AREA 1 - CENCANo-mix toilet

Composting chambers

Wetlands

Fat keeper





AREA 2 - ALTERNATIVA

• A pilot project in Ciudad Nuevo Pachacutec in Ventanillawith the construction of:

- 17 water reservoirs of 1500 m3

- 837 public water taps

- 140 ecological toilets + green gardens + rabbits





Baño Ecológico

Sistema de tratamiento

Sistema de riego

AREA 2 - ALTERNATIVA

Fat Keeper

Wetland

No-mix toilet

Men urinal

Green garden

Rabbits





Results: Project explains performance

1.0 0 2.0 0

A re a

0 .0 0

10 .00

20 .00

30 .00

40. 00

50 .00

60 .00

70 .00

1 1 11

S ta te o f M a ite na nc e

S y st em p erfo rma nc e

ALTERNATIVACENCA





Why area matters for system performanceCENCA ALTERNATIVA

House property Inheritance Donation from government

Middle income(Soles/month)

340 530

NGO involvement after project finished

Yes No

Inhabitants selected sanitation technology

Yes No

Inhabitants designed their toilet

Yes No

Inhabitants paid for the toilet

Yes (only the 40%) No

Tap water Yes No

Toilets close to each other Yes No

Inhabitants manage the system

Yes No

Users identified with the system

Yes No





Conclusions

1) ECOSAN technology works is affordable, safe andeasy to use

2) But big differences in system performance betweenhouseholds

3) Involvement (area) and income explain only 40% ofthe variation in field performance





Bayawan City, FilipinasMASTER THESIS MARIA DE LANGE

Wageningen University





• Fishermens Village Gawad Kalinga• 700 households • Hybrid wetland• Mixed wastewater treatment: all the

wastewater from toilets, bathrooms and kitchen sinks of 3000 people

• City engineering office is responsible for the operation and maintenance

Bayawan City, Filipinas





De Lange, 2010






User satisfaction evaluation

• 70% of the inhabitants are satisfied• Problems with odor at start-up

� Solution to open the valve at night

• Cheap WWT but costs still high: � The total construction costs of the wetland are estimated at

P10 million (€164.000). � The annual operation and maintenance costs are estimated at

P400.000 (€6557)

• Low simple maintenance






Cali, ColombiaAPPLICATION OF NATURAL TREATMENT SYSTEMS FOR

WASTEWATER POLLUTION CONTROL IN THE EXPANSION AREA OF CALI, COLOMBIA

A. Gaviano, D. A. Zambrano, A. Galvis and Diederik P.L. Rousseau





Case study

• Comparative study for the application of constructed wetlands in expansion areas of Cali, Colombia

• Three alternatives evaluated:

a) primary facultative ponds, b) anaerobic and secondary facultative ponds in seriesc) anaerobic ponds and sub-surface flow constructed

wetlands in series

• For each of these three alternatives, the additional implementation of rock filters, maturation ponds and fishponds has also been considered.





Cali, Colombia

• 238,916 inhabitants• Average water demand: 142.8 L/s• Temperatures: 20 and 30 °C• Precipitation levels around 1000

mm/year• Total wastewater flow estimated to be

30,000 m3/d.





Design parameters• Both conventional and high rate anaerobic ponds have been designed. A

volumetric BOD loading rate of respectively of 340 and 700 g/m3/d has been considered.

• Facultative ponds have been designed with a surface BOD loading rate of 330.5 kg/ha/d.

• Rock filters are designed for a hydraulic loading rate of 1 m3/m3/d. • Maturation ponds were designed to reach levels recommended by the

World Health Organization: < 1 egg/l for Helminthes and 3 log• reduction for Escherichia coli (for highly mechanized restricted irrigation

such as sugar cane cultures).• Fishponds are designed as integrated agricultural-aquacultural

alternatives on the basis of a surface loading rate of Total Nitrogen of 4 kgN/ha/d. Partitioning of the influent flow has been

• necessary to reduce fishpond area requirement.• Constructed wetlands have been designed on the basis of the k-C*

model (Rousseau et al., 2004).

Removal efficiencies

Construction and maintenance





Alternative C





Conclusions• All natural systems have economical benefits as

compared with the construction of the new WWTP with activated sludge;

• Effluent of natural system is better and can be used for crop irrigation.

• Integrated agricultural-aquacultural solutions could be planned and even energy production would be possible (high rate anaerobic ponds).

• Further detailed economical analyses are necessary (reuse of effluent and recuperation of biogas).

• Detailed studies on sugar cane cultures water demand and geological and geotechnical analysis are necessary





Spain

CONSTRUCTED TREATMENT WETLANDS CONTRIBUTING TO THE PARADIGM SHIFT IN SUSTAINABLE URBAN WATER

MANAGEMENTD. Rousseau, P vd Steen, H. van Bruggen, and P. Lens





• Near Barcelona• Restauration river

Congost • 1 ha Surface Flow

CW• In operation since

April 2003

Granollers, Spain





• Marsh-pond-marsh type: Combines open water with reeds

• Planted with reed (phragmites) and bulrush (typha)

• Fed with secondary treatment effluent• Depth :

a) 1,5 m in open water zone b) 0,4 m in planted zones

• Construction costs 72.000 euros

Granollers CW





• Serves various purposes:a) Effluent polishing before discharge: NH4

+

and pathogensb) Landscape restorationc) Habitat functiond) Future uses: horticultural companies, street

cleaning, irrigation of public parks

Granolles CW





Performance• HLR=10 mm/day• NH4

a) from 31 to 4 mgN/Lb) 55% of effluent fulfilled standard of 2mg N/L. c) Standard exceeded in autumn and winter: temperature= low

denitrification

• faecal coliforma) 85% samples below 2400/ml = target value for the design

Granolles CW





Performance• Also removal of pharmaceuticals and natural care

products• Nature restoration:

a) 86 present species of vascular plants b) 35 avian species visiting or nestingc) Amphibans present in outlet vs. absent in inlet

Granolles CW





Modeling of constructed wetlands

RECENT ADVANCES IN MODELLING OF NATURAL TREATMENT SYSTEMS

Diederik P.L. Rousseau and Tineke M. HooijmansUNESCO-IHE Institute for Water Education, Department of Environmental Resources, Delft, The Netherlands (e-mail:

[email protected], [email protected])





Modelamiento de Wetlands• Usually design is based on tables using OLR values• When used models are empiric or first-order

• Pitfalls:a) only valid for (near) optimal hydraulic conditions b) can only be used to predict average pollutant values over

longer time periods. c) high degree of uncertainty because of the strong

simplification of degradation pathways.

• As a result designers tend to use high safety factors, resulting in robust but larger-than-necessary systems.





Modelamiento de Wetlands• Mathematical representations of all major removal pathways• Overviiew of wetland models has been given by Langergraber et al.

(2009a), • Models available specially for subsurface flow constructed wetlands. • Models couple flow models with reaction models. • Horizontal flow systems can be simulated when only water flow

saturated conditions are considered• Transient variably-saturated flow models are required for modelling

vertical flow CW with intermittent loading.: highly dynamic, adding complexity o

• Most advanced reaction models : CW2D (Langergraber and Šimůnek, 2005), FITOVERT (Giraldi et al.,2008), and in the model developed by Ojeda et al. (2008), that considers processes affecting solids, organic matter, nitrogen and sulphur.





Modelamiento de Wetlands• CWM1, Constructed Wetland Model No. 1 (Langergraber et

al.,2009b),:a) a general model to describe biochemical transformation and

degradation processes for organic matter and nitrogen in subsurface flow CW. CWM1 describes aerobic, anoxic and anaerobic processes and is therefore applicable for both horizontal and vertical flow systems.

b) Seventeen processes and 16 components (8 soluble and 8 particulate) are considered.

• large amount of parameters makes them difficult to calibrate and therefore to apply.

• research outputs rather than engineering tools.





Wetland modelling





• Solutions for greywater treatment depend upon available space and type of reuse

• Natural systems have good acceptance and allow for more involvement of the user. Require monitoring and good pretreatment

• N and P removal require proper design• Micropollutants and hormone removal is a

challenge and question mark

FINAL COMMENTS

THANKS