Constructed Wetlands for the Provision of Irrigation Water a Resource for a Production of Regrowing Raw Products?

Transcription

1 R.A. Müller, P. Kuschk, D. Pareides and O. Baeder-Bederski Constructed Wetlands for the Provision of Irrigation Water a Resource for a Production of Regrowing Raw Products? Ecological Sanitation Symposium Damascus / Syria 11-13th December

2 Introduction: Motivation for Research Activities Global perspective European/German perspective Inadequate implementation of efficient and transferable technologies for water supply and waste water treatment Indicated by a mortality rate of app. 5 Million people per year (WHO) Biggest water consumer: agricultural plant production European Water Framework Directive ( ): River basin management Increasing importance of solutions for decentralized water management Necessity of intelligent opening-up strategies for new sites/areas Necessity to maintain the high hygienic standard

3 Decentralised Water Management water consumption partial flow 1 partial flow 2 decentralised treatment decentralised treatment water recycling groundwater recharge advantages systematic treatment of different partial flows no cost-intensive sewer system high variety high flexibility utilisation of nutrients direct relation to the polluter in agreement with a sustainable management of resources Training and Demonstration Centre for Decentralised Sewage Treatment

4 Alternative Water Management Strategies drinking water faeces, urine and waste closing the loop of water and nutrients nutrients Training and Demonstration Centre for Decentralised Sewage Treatment cleaned water

5 Possible mechanisms of Germ removal Chemical Parameters Physical mechanisms Redox Potential Oxigen Conc. Temperatur Salinity Protozoa TOC Biological Mechanisms Plant Rhizosphere Protozoa Bacteriophage Competing bacteria C-input Biocide O 2 -input In Matrix: Filtration Sedimentation Biofilm Adsorption

6 Objective: CW s for supply of irrigation waters Test and optimization of soil filters regarding the elimination of bacteria and parasites in a pilot plant scale and under practical conditions different basic design (hydraulics, filter materials, planting) different operating regimes (hydraulic surface loads, feeding cycles) Adaptation of the design, comparison of the performance, and dimension for an advanced reduction of faecal indicator organisms comparative test operation of two similar constructed pilot plant systems (35 p. e.) in Germany and Mexico, long-term test improvement of a full-scale plant for about 300 p e in Germany

7 Hygienic quality of irrigation water Maximum allowable concentrations WHO Techn. Rep. Ser. 778 (1989) Use of wastewater in agriculture and aquaculture DIN standard (1999) Hygienic concern of irrigation water coccus NOM-003-ECOL (1998) Reuse of treated waste water in the public domain Coliform Bodies MPN/100 ml Cat. A a) : 200 (FC) Cat. A: 1000 (FC) Cat. B: - (FC) Class 1: n. d. (EC) Class 2: 200 (EC) Class 3: 2000 (EC) Dir.: 240 (FC) Ind.: 1000 (FC) Entero- MPN/100 ml Salmonellae detection/l Intestinal Nematodes counts/l FC Faecal coliforms (termotolerant coliform bodies) EC Escherichia coli Parasites: Ascaris sp., Trichuris sp., hookworms - no standard recommended n. d. not detectable a) Public lawns, possible contact of children age < 15 years b) Threshold for further tests n. d n. d. n. d. n. d n. d. n. d. n. d. 1 5 BOD 5 mg/l b)

8 Pilot plant system

9 Experimental Program Construction of two Sister Pilot Plants Leipzig Langenreichenbach/Mexico Xochitla-Site Year 2001: Adaptation/Optimization of pretreatment, modification of the bed construction Year 2002 Hydraulic loading tests: Single-stage systems 2003/2004 Long-term experiment: Optimized performance (e. g. coupled systems) 2005: Implementation of the technology Fundamental research

10 Pilot system Langenreichenbach Foto: Künzelmann/UFZ Site: Capacity: Waste water: Saxonia (Germany), Village Langenreichenbach 35 p. e. pretreatment, 1.5 p. e. each bed Operator: Center for Environmental Research Leipzig-Halle GmbH municipal, from an influent of a p.e. sewage plant Design: 8 vertical-, 6 horizontal beds and 1 pond, planted with Phragmites C. Plant age: 4 years

11 Filter Design Vertical Filter A = 6 m 2 Horizontal Filter

12 Raw Waste Water Design of the pilot system Horizontal Filters: H Force main Legend planted c P Soil Filter: Exclay/Sand f Soil Filter: Sand Pretreatment: Straw Filter Effluent Pumps + on-line Measurement Technique Vertical Filters: V

13 Pilot system Langenreichenbach Foto: Künzelmann/UFZ Quality of pretreated water C S C COD C BOD5 S NH4-N S NO3-N C Nt E. coli mg/l mg/l mg/l mg/l mg/l mg/l lg(mpn/100 ml) Median ,8 76 6,9

14 Parameters and additional methods

15 Waste water analysis Microbiological/Parasitological Physicochemical Parameters Parameters total bacterial number (CFU) at chemical oxygen demand COD 22 C and 36 C thermotolerant coliform bacteria biological oxygen demand BOD 5 Escherichia coli ammonia- nitrogen Enterococci nitrate- nitrogen Salmonella total nitrogen Clostridia ortho-phosphate Cryptosporidium oocysts water balance Giardia cysts bromide (tracer tests) Intestinal nematodes (Ascaris spp., turbidity Tichuris spp., Hookworm)

16 General results

17 1st stage vertical flow (exp. clay) 2nd stage horizontal flow (sand) Reduction of the Chemical Oxygen Demand O 2 -Demand [mg/l] Effluent q e [L/m 2 d] nd stage Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan st stage 0 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan qnom BOD 5 2 nd stage COD 1 st stage COD 2 nd stage BOD 5 1 st stage T Soil [ C] COD Influent q e (HfP1) T Soil (HfP2) T Soil (VcP1)

18 10 9 Reduction of E. coli by means of singlestage filters Influence of the filter design Feed 40 L/m 2 d (Jun. - Sep. 2002) E. coli [MPN/100 ml] Samples = Determinations = DIN Class 3 17 (34) 17 (34) I r I p 8 (16) 10 (19) VcP1 Vc 14 (28) 6 (12) HfP1 Hf 9 (18) 9 (17) HcP1 Hc 6 (6) 7 (7) VfP1 Vf I influent H horizontal filter V vertical filter r Raw water p pretreated water f fine material: sand c coarse material: exclay P1 planted, basin 1

19 10 9 Reduction of E. coli by means of combined filters Influence of the filter design Feed 40 L/m 2 d (Sep. - Oct. 2003) E. coli [MPN/100 ml] Samples = (Determinations) = WHO 5 (5) I r 5 (5) I p 5 (5) Hc 5 (5) Hf 5 (5) 5 (5) V f P1 H cp1 minimum value 30 MPN/100 ml 5 (5) 5 (5) V cp1 H fp1 I influent H horizontal filter V vertical filter r Raw water p pretreated water f fine material: sand c coarse material: exclay P1 planted, basin 1

20 Reduction of E. coli by means of combined filters E.coli [MPN/100ml] 1e+9 1e+8 1e+7 1e+6 1e+5 1e+4 1e+3 1e+2 1e+1 1e+0 E.coli (DIN EN ISO ) n = 15 n = 14 n =15 n = 13 n = 15 n = 14 n = 15 Minimal Value 15 [MPN/100 ml] VfA HcA VcT HfT VfT HcT Inflow H horizontal filter V vertical filter A Arundo Donax p pretreated water f fine Tezontle c coarse tezontle T Typha latifolia

21 Influence of temperature Stability of performance

22 1st stage vertical flow (exp. clay) 2nd stage horizontal flow (sand) Effluent q e [L/m 2 d] E. coli [lg(mpn/100 ml)] E. coli reduction minimum value 30 MPN/100 ml 1 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan qnom HfP VcP Ip DIN class T Soil [ C] q e (HfP1) T Soil (HfP2) T Soil (VcP1)

23 Additional microbiological parameters

24 Reduction of intestinal nematodes Results from the Langenreichenbach plant, Germany Lab A June 2005 Lab B August 2005 Lab B October 2005 Combination Sample Type hydr. load Test volume eggs test volume eggs test volume eggs L/m2 d L per 1 L L per 1 L L per 1 L ROH Raw n.n NF Pretretated n.n. V -H VfP1 1. vertical flow n.n. 10 n.n. 2. horizontal flow n.n. 10 n.n. HcP1 10 n.n. 9 V - H VcP1 1. vertical flow n.n. 2. horizontal flow - 10 n.n. HfP V - H VcP2 1. vertical flow n.n. 10 n.n. 2. horizontal flow n.n. 10 n.n. HfP V - V VcP3 1. vertical flow n.n. 10 n.n. Vcc 2. vertical flow 10 n.n. 10 n.n. 10 n.n. 1. aerated pond 10 n.n. n.n. - - P - H P , horizontal flow 10 n.n. - - HcP2 2,7 10 eggs Identified nematode eggs of Ascaris-, Trichuris-, or hookworm type H horizontal filter c coarse material: exclay/sand V vertical filter P1 planted, basin 1 f fine material: sand

25 Outlook: Bamboo Production from domestic Wastewater - a Columbian Case Study

26 ecosan Kreislaufwirtschaft und Stoffstromorientierung im Abwassermanagement Excrements are valuable resources Million tons per year (N + P 2 O 5 + K 2 O) global mineral fertilizer consumption 50 Global Fertilizer equivalent from Wastewater source: more than 1/3 of global mineral fertilizer consumption can be covered by the recycling of human excrements fertilization materials in the value of 15 billion USS are down-rinsed the toilet annually 26

27 ecosan Kreislaufwirtschaft und Stoffstromorientierung im Abwassermanagement Material flow quantities and their contents 20 12,3 kg 14,1 kg l ,3 kg 3,6 kg K P N 0,8 kg 1,0 kg Organic kg COD/ (Person Year) Nutrients kg N,P,K / (Person Year) Grey Water 500 l 50 l Grauwasser Urin Fäkalien Urine Faeces Volume Liter / (Person Year) source: Otterpohl 27

28 ecosan Kreislaufwirtschaft und Stoffstromorientierung im Abwassermanagement Fertilizer Equivalence Fertilizer Equivalence of Yearly per Capita Excreted Nutrients and Fertiliser Requirements for Producing 250 kg of Cereals 6 Nutrient (kg) cereal requirements faeces urine 1 0 N P K N N P P K K source: Drangert,

29 General Concept Construction Wastewater Economic Benefits Environmental Benefits Furniture Laminated flooring Charcoal Mat board Hygienization Contaminants removal

30 General concept: Bamboo Big distribution along Latin America. Guadua angustifolia. Different uses and high demand. High growth rate.

31 Use of Bamboo for wastewater treatment Colombian experience: Small scale experiments (8 m 2 ). Domestic wastewater (UTP campus). BOD removal higher than 80% (HRT 1 d). Total and fecal coliforms removal rate higher than 10 2 log (HRT 1 day). With domestic wastewater Guadua shows similar or even higher growth rate in comparison with natural and optimum conditions. Fertilizers increase productivity in 45%

32 Economical Analysis Operation and Maintenance Costs in WWT System in Pereira, Colombia Item COP $ Salary (1 person) Sludge Removal (Septic tank) Monitoring Total WWT System: Population: 550 inhabitants Sewerage system: Combined Wastewater: 210 l/p/d Average flow: 1,34 l/s (2002) Average temperature: 22 C Septic Tank and subsurface constructed wetland

33 Economical Analysis (II) Tree Density (Trees/Ha) 6300 Yield (Trees/Ha/year) 800 Production costs ( /tree) 1.11 Tree price at the farm ( /tree) 1.52 Profitability ( /tree) 0.41 Income ( /Ha/Year) 326 Area for the pilot project (Ha) 3 Total Income ( /year) 978 It is possible to spare, in this case, 23% of the running costs. Bigger projects will be more profitable!

34 Outlook It is possible to perform constructed wetlands as a basic decentralised technological module in sustainable water management strategies. technical Low operation costs especially in terms of energy consumption, sludge removal and maintenance Pathogen-removal efficiency works well and enables this passive technology to overtake a function in water-supply and wastewater-treatment strategies (water recycling) According to the social relevance the active transfer of technology by an intensive dialogue/co-operation between scientists, politicians, companies, technologyusers has to be prepared (tool: Demonstration plants)

35 Offer for Co-Operation Transfer of experiences towards site specific conditions in Syria Installation of a Demonstration and Training site Syrian-German Cooperation: Precondition for Implementation of decentralized technical solution in water management systems

36 Contact Dr. Roland A. Müller UFZ-Leipzig-Halle GmbH www: bdz-abwasser.de

37 Frequency of occurrence of Salmonellae spp. Results from the Langenreichenbach plant, Germany Samples = 23 (Median) Determinations: 3-4 Raw Pretreated Pond Hc Hf VcP3 Vcc VfP1 HcP1 VfP2 HcP2 Vcp1 HfP1 VcP2 HfP2 H horizontal filter c coarse material: exclay/sand V vertical filter P1 planted, basin 1 f fine material: sand P Pond Samples Salmonellae detected [%] 0

38 Pretreatment Straw filter for primary treatment to charge red bed sand filters (Germany)