VIETNAM JOURNAL OF CHEMISTRY VOL 51(2) 257 263 INTEGRATED MANAGEMENT CONCEPT FOR CRAFT VILLAGES IN VIETNAM REGARDING WATER WASTEWATER, WASTE AND RELATED ENERGY Tran Thi Nguyet'''''''', Sebastian Meier''''*, Ce[.]
VIETNAM JOURNAL OF CHEMISTRY VOL 51(2) 257-263 INTEGRATED MANAGEMENT CONCEPT FOR CRAFT VILLAGES IN VIETNAM REGARDING WATER WASTEWATER, WASTE AND RELATED ENERGY Tran Thi Nguyet'', Sebastian Meier'*, Celia Hah^^ Dirk Weichgrebe', Peter Werner^ Karl-Heinz Rosenwinkel* 'Institute for Sanitary Engineering and Waste Management, Leibniz University Hannover Welfengarten 1, D-30167 Hannover Germany ^Institute of Waste Management and Contaminated Site Treatment, Technical Universityof Dresden, Pratzschwitzer Str 15 D-01796 Pirna, Germany Received 19 September 2012 Abstract The INHAND project is studying the liquor processing craft village of Dai Lam situated on the bank ofthe heavily polluted River Cau in BacNinh province about 40 km NE of Hanoi, The objectives are to investigate all wastewater and waste streams for a material flow analysis and finally to develop an integrated management concept of water, wastewater, solid wastes and energy Inventory information such as socio-economic data and parameters ofthe in- and output streams and production processes has been collected by comprehensive questionnaires Approximately 17% of the interviewed households nowadays are producing alcohol, about 7% something else like rice noodle and tofti Pig raising is dominant as secondary activity of production The amount of wastewater which is discharged mto the open channel was measured and calculated approx, 686 m* per day with about 600-700 mg COD/L and 140-200 mg TN/L COD which is to times higher than the Vietnamese standard The wastewater is organically polluted mainly from production activities The data form the basis for designing and constructing a multi-step wastewater pilot plant During the operanon ofthe pilot plant scientific investigations and monitoring will be carried out Keywords: Wastewater, liquor, Dai Lam, production, treatment, biogas plant, management, material flow INTRODUCTION Craft villages have been playing a significant role in the development of Vietnam's rural economy for a long time It is documented that already in the 11th century crafts in the Red River estuary were mainly produced in villages located in the surroundings of Hanoi Although their structure changed dunng die communist era and again following the opening policy doimoiin 1986, traditional craft villages still are places of high productivity The range of products and production methods including the processing of materials and chemicals are now adapted to modem market requirements, but environmental and labour protection issues are not adequately considered in the management of craft villages Reasons are various: poor education of responsible operators, deficient technical equipment or missing regulatory framework and implementation of existing regulations, respectively In the frame of a fact fmding mission of the German ministnes BMBF (Federal Ministry for Research and Education) and BMZ (Federal Ministry for Economic Cooperation and Development) with the Vietnamese authorities the province of Bac Ninh was identified as a model region for a study to ameliorate the environmental sitiiation in craft villages focusing on food processing industnes which generates typically high quantitiesof organic wastewater [VEM, 2008] The INHAND project "Litegrated Water Management Concept for Craft Villages" started in 2011 and is stiidying the food production village of Dai Lam The duration of the joint research project is 3.5 years Four German and diree Vietiiamese partners are involved m the project: Technical University of Dresden, Institiate of Waste Management and Contaminated Site Treatment (L\A); Leibniz University Hanover, histiftite of Sanitary Engineering and Waste Management VJCVol 51(2), 2013 (ISAH); Herbst Umwelttechnik GmbH; VIS International GmbH, Vietnam Academy of Science and Technology, Institute for Environmental Technology (VAST); Hanoi University of Science, Faculty of Chemistry, Lab of Environmental Chemistry (HUS) and the commune of Tam Da commune (Yen Phong distiict, Bac Ninh province) The aim of project is to research and establish an integrated water management concept of Dai Lam, which IS a rice and cassava alcohol processmg village In the first phase of project basic information were gathered such as socio-economic and physical, chemical and biological data of all output stieams especially wastewater released from production activities and wastewater in final discharge channel of village This has been done by questionnaire investigations, regular monitonng campaigns, experiments and onsite measurement During the second phase analysis of the material flow will be earned out and a pilot plant will be designed, constructed and set into operation The pilot plant consists of three steps: aerobic wastewater tieatment, anaerobic tieatmentplant and a low energy digestate drying facility The final phase is the testing and adaptation stage: the pilot plant will be set into operation in cooperation with the local operator Environmental monitoring and scientific investigations shall be developed during the operation of the pilot plant The result of the project can be exemplary for other food processing craft villages in Vietnam INVENTORY DATA COLLECTION In the first phase of project, inventory data on basic-socio economic data, production processes, water and energy use, and solid waste management were gathered by interviewing of over 250 households in village Dai Lam with comprehensive questionnaires The main questions are about family status, land use, water use, health aspect, wastewater and drainage system, solid waste status, energy use, household biogas plants The gathered informative data have been actualized on Geographic Information System (GIS) by using ArcGIS 10 Samples of wastewater from main channel, production processes and other organic substiates like pig manure, water hyacinth, and residues from production processes like cassava and nee stillage were taken in Dai Lam dunng monthly sampling campaigns Temperatiore, pH, and conductivity were determined on-site COD^^,, COD^i^bie, BODj, TS, VS, P„tai, Nwui, NH^N, and Cl" were analysed at the laboratory of die Centre for Nahiral Resources and Environmental Monitonng in Bac Nmh, at Leibniz Iran int Nguyet, etal Universitat Hannover and at the Hanoi University of Science Biogas potentials of organic substi-ates like pig manure, water hyacinth, rice and cassava stillage and wastewater from cassava soaking process and noodle production were found out by implementing anaerobic batch test according to German guideline VDI 4630 [3] at Hanoi University of Science and Leibniz Universitat Hannover Information on daily fluctuation of wastewater quantity and characteristics were defined This wastewater was produced from most households in the village, it is then collected in an open channel and released to an irrigation and drainage channel system in the ricefields, another smaller part ofthe households discharges wastewater directly into the Cau River Wastewater amount was measured by constructing a canal in a sewer lane and additionally measured by flow meters in 24 hours The onsite determination of physical and chemical parameters was done for temperature, pH, conductivity, COD, TN, NH4-N, NO3, and NO2 Furthermore, the production processes of alcohol, noodle, and tofu were investigated by home-stay surveys These investigations were focussing on the quantity of all input and output streams Wastewater generation was measured directly for the whole production processes using simple equipment like buckets, balances, stopwatch, pump, and rulers Samples were taken to determine physical and chemical properties The results were perfonned in MS-Excel* and UMBERTO* software to establish balances of material and energy This is the basic step for realising indicator parameters for further cfTective management of water, wastewater and waste stieams As the wastewater will be anaerobically heated, other sources of organic materials should be investigated to be co-digested with the sewerage sludge A campaign on solid waste and organic waste was implemented, therefore domestic waste was collected from approx 118 households, after sorting, the samples were analysed on their physical and chemical properties Anaerobic batch tests were carried out using for garden waste and household waste in order to find out biogas potential hi the second phase, a du-ee-step wastewater and biogas pilot plant has been set up based on abovementioned results, hi this system, wastewater and other biodegradable substiates shall be tieated together anaerobically in order to realize a carbon neutial fransformation to biogas The pilot plant includes (1) aerobic freatment facility, (2) anaerobic freatinent facility, and (3) low energy facility for digestate freatinent Each part will fit the current state of the art, but die components need to be VJCVol 51(2), 2013 Integrated management concept for materials Currently, all wastewater sfreams are mainly collected by a drainage system in the 23 sewer lanes, after that the wastewater is drained into a main canal along village and finally into an open sewer, which leads to the canal system of the surrounding rice fields The septic tanks for sludge tieatment at end of each sewer are over loaded and the management or maintenance of sewer is lacking RESULTS AND DISCUSSION resulting in accumulation of solid waste and sludge The inventory interviews of households and in drainage system It might be a new challenge to village leaders show that approximately 17% of the the operation of the pilot plant in near future if the interviewed households are involved in the wastewater can not arrive treatment point Adjacent processing of rice and cassava liquor, while the rest to immense sanitary problems this possibly of 7% producing food, like noodle, cake, tofu, confributes to eufrophication of surrounding water pancake, slaughtering or producing aluminium, bodies and other changes of the ecosystem, e.g a glass, paper, iumiture or making fine art Residues vast modification in subsoil redox conditions and from die food production is used to raise pigs, might lead to further mobilisation of geogenic therefore pig farming is dominant as secondary arsenic The collected information from household activities For this reason the wastewater contains surveys has been actualised on GIS for a thematic high and seasonal varying amount of organic map as showed in figure I adapted to the local preconditions Regular monitoring activities are plarmed in accordance with other scientific investigations during operation of pilot plant The utilisation of biogas and digestate shall be considered in relation with scientific aspects and local condition ã r ^ I ',;^;_ta3SđaA, Legend Cau River V ^ ^ ^ Sewer s [_ J Ricefield 1 m m i l Pilot plant m Sediinentation_tank ^ ^ Waterwor1( 1 Street 1 Parcel i h e a Fig 1: Detail ofthe thematic map of Dat Lam established by using ArcGIS 10 The result from onsite measurement showed that wastewater generation, which connected to the sewer system was 686 m^/d and the peak was in morning time at around 8:00 AM The flow rate variation is showed in figure The generation of wastewater peaks in the morning and in the late afternoon because production and household activities take place in these time intervals In comparison tii wastewater from odier food production villages, die waste water generated from village Dai Lam is slightly lower as presented in Tran Thi Nguyet, etal VJC, Vol 51(2), 2013 figure [2], The reasons are various depending mainly on population, production intensity productivity Hence, the measurement will be repeated in high productivity times in order to get more information on the seasonal variability D - • IIM 1000 ll 1" lllnllllliiiillll Pliu Do twimlce QI (NI5-N23) flow rale of wastewater measured from sewer lane IS (NI5) to sewer lane 23 (N23) Q2 (NI-NI2) flow rale of wastewater measured from sewer lane I (NI) lo sewer lane 12 (NI2) Qlolal flow rale of wastewater calculated for 23 sewer lanes The 24-hour-measurement represents the wastewater production in the season of low In parallel onsite analysis were done during the measurement of wastewater; CODu^ and TN concentration were measured about 600-700 mg COD/L and 140-200 mg TN/L respectively.These values access the permitted limits 3-6 times for industrial wastewater discharge [4] ^ iril 1 - , - , lciL*ôri majj ""' ã " ã " " - ii „ r,i- „, *'i \ bi,,.—^ ^ i „., „ I - sn, ^""ã" '^' ' > -r"Z-! j hMfôMM ,ô ^ ô -= ,.u, ằ,., S , ã HHiinCriBMa CH.™™" |c„w«,i »- >fSHtMir*>IMIin9il j^^_^^^^^^^^^^— 1"' W - " D«i U m Uquor TjnDoliauoi Fig Comparison of wastewater generation in Dai Lam with some food processing villages in Vietnam Fig 2: Flow rate of wastewater in village Dai Lam measured on 24.-25.04.2012 ICllWittrJ ^ ^ H 1""" mnn "r ™, ^ rsu ^ ftf RUlMl m.»>^^ , _ "SS (»».» _ M ^ J ^ "i-S IMHUmt [/•MAm - " - " - , IIMU ] • - ' — ^ —I ,^,l-l ' "^1 « « ' * ' zi Fig 4: Procedure and balance of cassava liquor production VJCVol ^ ) ^ ^ Integrated management concept for Biogas yield of different substrates in gas and liquid phase Fig 5: Biogas potential and relationship of methane and carbon dioxide of different substiates in gas and liquid phase determined by VDI 4630 Table 1: Biogas potential and biogas quality of different subsfrates in Dai Lam Parameter Unit Rice Cassava Water Kitchen Pig Stillage Stillage Manure Hyacinthe waste Total solids [gTS/kg (TS) osi Ignition loss [%rel.TS] (lorVS) Ignition loss [gTS/kg (HorVS) OS] Total Amount of gas (In gas Methan [% CH,1 Carbondioxid ["/oCO^l [ml„CH4/g Methane TS yield Substrate] [miN Biogas/ Biogas yield gTS Substrate! Reference Biogas yield [HIIN Biogas/ gTS Substrate 109.8 73.7 222.4 81.2 117.4 Garden soaldng water 194.0 Cassava boiling wast water 18.0 21.6 Cassava soaking water 89.9 86.3 76.6 84.0 80.1 79.3 73.8 90.8 98.7 63.6 170.4 68.2 94.1 154.0 13.3 20.1 and liquid phases) 54.4 57.7 61.1 42.3 45.6 38.9 311.5 280.2 213.3 53.6 46.4 158.6 59.0 41.0 188.9 61.9 38.1 116.0 63.5 36.5 378.4 51.8 48.2 324.1 595.9 626.0 I-l [-1 539.8 515.0 349.1 295.8 320.3 187.4 [5] 700.2 [5] 662.7 [61 298.6 [71 245.0 [8] 251.65 [81 251.65 [5] Calculated by WEENDER - Analysis (DLG, 1997) for Rice 15[ Calculated by WEENDER - Analysis (DLG, 1997) for Cassava root [6] KTBL, 2007; [7] Chanakya, 1993; [8] Hahn (2010) for biowaste iran Im Nguyet, etal VJC, Vol 51(2), 2013 As mentioned before, the main production in Dai Lam village is liquor; the investigation on production processes showed that wastewater from cassava alcohol production is high in volume and organic content Figure shows an example of a material and energy flow balance for cassava liquor production m excel format as a result of this investigation The balances of all production process will be performed later by material flow analysis software UMBERTO® The biogas potentials of some substrates were determined by Anaerobic Batch Test [3] Figure shows the biogas yield and biogas quality of different subsfrates like wastewater from cassava liquor production, garden waste and kitchen waste in Dai Lam The biogas yields of wastewater from cassava alcohol production were high compared lo those of other subsfrates like pig manure, water hyacinth, organic waste in Dai Lam as described in Table It can be concluded that subsfrates are easy biodegradable and have high biogas potentials These results of regular monitoring, wastewater measurement and anaerobic batch test are significant data for setting up a three-step wastewater freatment plant which was designed and now conshucted in Dai Lam as illusfrated in figure Recshing stream PrDCMi water drain ::r":j 2r