management of faecal sludge through co-composting
MANAGEMENT OF FAECAL SLUDGE THROUGH CO-COMPOSTING APPROACH IN KUSHTIA MUNICIPALITY OF BANGLADESH N.A. HAFIZ*, S.M.T. ISLAM**, M. ALAMGIR* *Department of Civil Engineering, Khulna University of Engineering & Technology, Khulna-9203, Bangladesh ** Institute of Disaster Management, Khulna University of Engineering & Technology, Khulna-9203, Bangladesh
SUMMARY: On Site Sanitation (OSS) systems are the predominant form of excreta disposal installations in urban centers of industrializing countries. In broad sense it is called Faecal Sludge Management (FSM) deals with the management of sludge from OSS facilities while wastewater management deals with sewered sanitation. In developing counties like Bangaldesh FSM is practiced by some areas where better sanitation has achived. Kushtia Municipality in Bangaldesh is practicing FSM from November 2012 from the initiation of the project. The paper aims to find the overall FSM situation in Kushtia Municipality by FSM toolbox and evaluates the end product namely compost by combining both dewatered Faecal Sludge (FS) and Organic Solid Waste (OSW). The research emphasized on capturing relevant information and necessary sample collection for the fulfilment of the objectives. Through the “FSM Toolbox” the situation of FSM chain in Kushtia Municipality is fair to excellent and the end product known as compost is harmless and usable for cultivated zone. Although the knowledge of the FSM and FS’s resuing is better known among local peoples in Kushita, proper steps should be engaged for better FSM practice.
1. INTRODUCTION As many of the developing countries are moving towards increased sanitation coverage, the issue of safe handling of sludge has emerged as an important and challenging issue of concern. In the city, this challenge is even more acute due to the factors like high population density, rapid and unplanned growth, inadequate and often inaccessible service provisions. In cities where most households practice on-site sanitation, the emptying of septic tanks or pits, and transport of sludge to a safe dumping site for treatment becomes an emerging need (Opel, 2012). There is no doubt that if safe disposal of sludge is not ensured, gains achieved by increased sanitation coverage cannot be realized. Faecal sludge management (FSM) deals with on-site sanitation systems, while wastewater management is concerned with sewered sanitation. FS may be treated in separate treatment works or co-treated with sludges produced in wastewater treatment plants (Strauss et al, 2002). Research suggests that improved excreta management could reduce the diarrhoeal morbidity by 36 percent (Carr, 2001). Sludge management is usually limited to a de-sludging service that
Proceedings Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium/ 2 - 6 October 2017 S. Margherita di Pula, Cagliari, Italy / © 2017 by CISA Publisher, Italy
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
is provided by municipal agencies or the private sector, proper solutions for sludge disposal are generally lacking. However, in urban areas the negative impacts on the urban environment become too highand actions have to be taken (Strauss et al, 2002). In urban areas of Bangladesh, the excreta disposal situation is very alarming. Faecal matter from either open defecation or from on-site sanitation (OSS) installations such as pit latrines, septic tanks are discharged indiscriminately into drainage system, low lands, rivers etc (Yousuf and Waled, 2011). Along with the sludge collection, the disposal of the collected sludge is also a big challenge. It is neither put in a trenching ground nor treated rather it is a common practice in the urban areas as well as rural areas to disposenof in drains or in water bodies making the whole environment a havoc. Conventional sewerage system is absent in all urban areas except Dhaka where only 25 percent of the population is served by a sewer network (GoB, 2011). This paper presents the findings of a situation analysis of the existing FSM system in the town of Kushtia, Bangladesh. Then it goes the solution of the end product made from both dewaterd Faecal Sludge (FS) and Organic Solid Waste (OSW).
2. LITERATURE REVIEW 2.1 Country Sanitation Context Sanitation is still one of the biggest challenges for Bangladesh although it has made some good progress in increasing sanitation coverage over the past 25 years. In Bangladesh, levels of access to sanitation are relatively high. According to Millennium Development Goals (MDG) 2015, Bangladesh has a remarkable achievement by rapid drop of open defecation from 33% in 1990 to 6% in 2009, which ultimately reached to 1% in 2015 as reported in the country report on Sanitation (MGD: Bangaldesh Progress Report, 2016). However, in most secondary towns there are no sewers at all, with all the residents relying on on-site sanitation combined with faecal sludge management practices. In most cases there is hardly any effective or safe collection, transportation, treatment or disposal of sludge. Much of it ends up in water bodies or polluting nearby land. The World Bank estimates the economic costs of poor sanitation in Bangladesh total $4.2 billion each year. This was equivalent to 6.3 percent of Bangladesh’s GNP in 2007, or $29.6 per person per year (WSP, 2012). 2.2 Use of FS as a soil Conditioner/ Compost There are a wide range of FS treatment technologies that can be combined in many different ways. All treatment processes result in endproducts which are either treated further, disposed of, or harnessed in some way for resource recovery. The use of FS as a soil conditioner can range from deep row entrenchment of untreated FS, to bagged compost that is sold as a commercial product for household level use in horticulture. Moreover using as a soil conditioner it has an adavantage over using chemical fertilizer in farming lands. Controlled biological decomposition process of organic wastes into humus, a soil-like material is known as composting. Composting is nature's way of recycling organic wastes into new soil used in vegetable and flower gardens, landscaping and many other applications. Biological treatment is a very economical natural treatment process for organic solid wastes. In practice, the main biological process applied is generally composting. Composting is the biological degradation of highly concentrated biodegradable organic wastes in the presence of
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
oxygen (aerobically) to carbon dioxide and water, whereby the biologically generated waste heat is sufficient to raise the temperature of the composting mass to the thermophilic range (50 to 65oC). The final product of composting is a stable humus-like material known as compost. 2.3 FSM Situational Assessment Toolkit FSM Situational Assessment Toolikit (SAT) is a systematic process to assess the present situation of FSM in any designed location and help users to take part in FSM oriented options and programs. It also helps to identify the problems and possible solutions with the aim of better FSM situation in the future (FSM Toolbox, 2015). 2.3.1 What is a SAT Tool § §
Excel based tool Provide questions to assess and Identify FSM city existing situation for entire FSM service Chain
§ Report graphical summaries for city FSM status and challenges and problems – Dashboard
1&2
Figure 1. FSM situation dashboard
Figure 2. Steps involved in the situational assessment tool
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
2.4 Description of study area Kushtia zila comprises of only the sadar sub-division of former Kushtia zila. It is generally believed that the zila Kushtia might have derived its name from the word "Kushta" meaning Jute which was abundantly grown in this area. It lies between 23°42´ and 24°12´ north latitude and between 88°42´ and 89°22´ east longitudes. The total area of the district is 1621.15 sq.km (625.93 sq.miles). The annual average temperature of this district varies from Maximum 37.8ºC to minimum 11.2ºC and annual average rainfall is 1467 mm. Moreover some basic information regarding Kushtia Municiapality has shown in the following table. Table 1. Basic information regarding Kustia Municipality, Bangladesh Name of the Municipality Name of Mayor Municipal Area No. of Ward No. of Mouza included Total no. of Municipal Staff Population No. of Household No. of Holding
: : : : : : : : :
Kushtia Municipality Anwar Ali 42.79 sq.km 21 19 166 3,75,149 83,926 33,936
Figure 3. Location of Kushtia Municipality, Bangaldesh
2.5 Description of existing Faecal Sludge Treatment Plant (FSTP) § § § § §
From the observation, configurations of the existing FTP are summarized below: There are 2 units of sludge drying bed ( 2 beds x 6.05 x 10.2x 0.8 m as W x L x H).( Fig.4 and 5). The 2 inlet chambers are 2 chambers x 2.15 x 6.05 x 0.5 m. Installation of media in treatment beds is shown in Section plan drawing. The perforated tubes were also installed at the bottom of tank and connected to effluent tank. Hydraulic loading rate is 0.3 m3/m2 (by calculation) Timing to get dried sludge in each batch is depended on weather. It is may be more than 10 days or more than 20 days during raining season.
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
§ §
Maximum feed is 70 trips per bed (700L/trip) After sludge dried, it will be removed by manually.
Figure 4. Plan view of Existing FSTP in Kushtia
Figure 5. View of Existing FSTP in Kushtia
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
3. MATERIALS AND METHODS 3.1 Data collection and compilation The study applied both qualitative and quantitative methods for better understandings of varoious aspects and components relating to sludge management issues. For relevant information and data, a quessionaire was conducted through conservency department, City Planner, Assistant Engineer (water), Executive Engineer of Kushtia Municipality, Soil Research and Development Institute (SRDI), Kushtia office. After Collecting the information, FSM Toolbox specially SAT tool was applied to assess present FSM situations. The tool contains three different types of questions: Yes/In-process/No, Open-ended, and multiple-choice questions. Firstly, questions that can be scored are identified i.e. Yes/In-process/No and certain multiplechoice questions. Then according to questions, answers were put in the excel sheet and scores and were auto calculated by weighted average index. For three-option answers, the score of 1 was given to the option ‘Yes’ (‘best possible answer’), the score of 0 was given to the option ‘No’ (‘with considerable scope of improvement’) and the score of 0.5 was given to the option ‘In process’ (‘with a moderate scope of improvement’). Weighted Average =∑(Score* weight)/ Total Weight The assessment of the FSM situation was carried out based upon the answers that users select especially from Yes/In-process/No and from certain multiple choice questions, as those questions led to scores which will be reflected in the form of colors as an output of the assessment. Therefore, the answers of such questions have been observed in the form of reports in Dashboard 2 and the detailed information on the range of scores were also observed by clicking the information button in Dashboard 1. 3.2 Sample collection and laboratory tests A co-composting process was done in KUET campus, Khulna for gaining scientific and technical knowledge, skills and experiences in co-composting of OSW and FS. The random samples were collected from the existing treatment plant where faecal sludge is being dumped, from septic tank as well as from pit latrine. Then the FS was first pre-treated by dewatering in drying beds before co-composting with sorted OSW. Before that, the samples were taken for laboratory tests like Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Temperature, Nitrate-Nitrogen, (Ortho) Phosphate, Water content, Total and Volatile Suspended Solids, Total Coliform, Faecal Coliform, Sludge Volume Index (SVI), Electrical Conductivity and Alkalinity. Paralelly both a simple heap made with wooden frame and wire mesh (6 ft×4ft×2ft) and a drying bed of 8ft×8ft was made in KUET campus for further process. Dewatered FS was removed from the beds and mixed with sorted OSW. Then for composting, following tests were conducted: pH, Organic Carbon, Nitrogen, Phosphorus, Potassium, Sulphur, Lead, Calcium, Nickel, F.C, Helminthes eggs etc. In addition, relevant primary, secondary data were reviewed, pits and septic tanks emptying works were shadowed to generate accurate information.
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Figure 6. Sample Collection from a pit latrine in Kushtia Municipality, Bangladesh
Figure 7. Laboratory test of sample in KUET, Bangladesh
4. RESULTS AND DISCUSSION 4.1 FSM sevice chain FSM scorecard is the overall scenario of the FS management for any particular region. Kushtia FSM scenario is fair to excellent where different colors indicate the specific condition of the respective situation. From scorecard it is clear that, the general condition is fair (0.45-0.55). FSM chain is under excellent category where Containment is within range of 0.68-0.78, Emptying is within range of 0.79-0.89, Transportation is within range of 0.79-0.89, Treatment is within range of 0.68-0.78 and finally Reuse is within range of 0.79-0.89. The score of excellent indicates that, FSM situation is under low risk category and also suggest that the service delivery is largely on place. Figure 8 and 9 shows the detailed FSM scorecard and evaluates the overall FSM performance.
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Figure 8. FSM Service Chain Scorecard (Overall Situation of the FSM in Kushtia Municipality, Bangladesh)
Figure 9. FSM Chain Scorecard (Score and its meaining)
4.2 Test results of the FS and compost The visual characteristics of the compost made for experiment weighed 2.82 K.G. where the initail weight of the compost was 5.00 K.G. So the reduction in weight was about 43 % indicates that the combination of FS and OSW combindly reduces the percentage of wastes by making a reuseable material. Moreover, color, odor and moisture that was observed is satisfactory which depend on the local climate, constituents of the OSW, local human nature, etc. prototype compost was dary gray in color, absence of foul odor, and dry in combination. Other physiochemical characteristics like pH was observed 8.3 which at the end of maturation level. The pH remained above 8.0through the composting which shows the alkaline character of the material. There also a high level of Electrical Conductivity (EC) was observed after the end of composting perid recorded as 8.09 mS/cm. It needs to be considered that a high conductivity could be due to dissolution of sodium chloride which is not beneficial to plants. This is especially important for application of thecompost in agriculture since high soil salinity may inhibit plant germinationand growth (Cofie et al, 2009).
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Total Volatile Solids (TDS) and Fixed Solids (FS) are respectively 25.24% and 74.76% and Total Solids (TS) found as 707797 mg/L. Total Organic Carbon (TOC) found as 14.64 % which is within the standard value (10-25%). Total Organic Nitrogen (TON), Nitrate Nitrogen and Total Kjeldhal Nitrogen were fonud respectively as 2.00 % which is within the limit of 0.5-4.00%, 0.4 mg/L and 140 mg/K.G. The C/N ratio was used by many authors as one of the indicators of compost maturity. However, it cannot be used asan absolute indicator of compost maturity due to its large variation that is dependent on the starting materials. Never-theless,Wong et al. (2001) it was found that, a value around or below 20 is satisfactory (Wong et al, 2001). Bangaldesh Ministry of Agreiculture set a value of standards for compost where the C/N ratio would be maximum 20:1 and it was found of our compost as 7.3:1. So the C/N ratio after maturation level satisfied the above suggested limits and is suitable for addition to soil. Other all nutrient parameters and heavy metals concentration are mentioned in the following table 2.
Figure 10. Finished product (compost) (left: after screening and sorting, right: before screening and sorting)
The results of bacteriological analysis in compost found that, the most probable number of total coliform and faecal coliform were found respectively 1400 and 100 per 100 Ml of sample. On the other hand, nos of Helminth eggs was nill by observing through the microscope at 10x and 40x zoom level. Table 2. Shows the overall results of the compost with standard limits set by ministry of agriculture, Bangladesh for compost standards. Table 2. Basic parameters of the compost with standard limits Serial no 1 2 3 4 5 6 7 8 9 10 11 12 13
Characteristics Colour Odour pH Moisture (%) Total Volatile Solids (%) Fixed Solids (%) Total Solids (mg/L) Total Organic Carbon (%) Total Organic Nitrogen (%) C: N Nitrate nitrogen (mg/L) Electrical Conductivity (mS/cm) Total Kjeldahl Nitrogen (mg/ kg)
Result Dark Gray Absence of foul odour 8.3 29 25.24 74.76 707797 14.64 2.00 7.3:1 0.4 8.09 140
Standard Range* Dark gray to black Absence of foul odour 6.0 –8.5 Maximum 20 %
10-25 % 0.5 – 4.0 % 20:1 (maximum)
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
14 15 16 17 18 19
Phosphorus (%) Potassium (%) Lead (ppm) Nickel (ppm) Sulphur (%) Total Coliform (mpn/100 ml)
0.5 1.8 27 7 0.1 1400
20
Faecal Coliform (mpn/100 ml)
100
21
Helminth eggs (nos/L)
0
0.5-1.5 1.0-3.0 Maximum 30 ppm Maximum 30 ppm 0.1-0.5 ≤1000, WHO guideline 1989
(*compost standards, ministry of Agriculture, Bangladesh)
5. CONCLUSIONS Although there is a business potential of the proper FSM in Kushtia, there is a mere absence of proper FSM service which indicates that, there is a widespread lack of understnding awareness about its health and envoronmental impacts as well as its economic value. The FSM sevice chain shows the green marks in every portion, but this study therefore highlights the importance of working at different levels and with different pilot approaches so that the successful working model can be scaled up. The composting of both FS and OSW with a mixing ratio of 1.3 contained better result and properly treated endproduct is a stabilised organic product that may be safely handled, stored and applied to land according to guidelines of Ministry of Agriculture, Bangladesh. Although composting is a proven technology to produce a safe to use soil amendment, the local market demand for compost products should be evaluated as compost frequently does not have a significantly high market value. FS are disposed of or used in agriculture untreated in the majority of cases, creating enormous health risks, eye and nose sores and water pollution. From this point of view Kushtia Municipality FSM is effective and need more assistance for its sustainability.
REFERENCES Carr, R. (2001). Excreta-related infections and the role of sanitation in the control of transmission, Water Quality: Guidelines, Standards and Health, World Health Organization (WHO), Retrieved from http://www.who.int/water_sanitation_health/dwq/iwachap5.pdf Cofie et al. (2009). Co-composting of faecal sludge and organic solid waste for agriculture: Process dynamics, Elsevier, vol. 43, 4668-4669. FSM Toolbox. (2015). FSM Situational Assessment Tool: User’s Guide, www.fsmtoolbox.com, India: www.fsmtoolbox.com. GoB. (2011). Sector Development Plan (2011-25) of Water Supply and Sanitation. Dhaka: Local government Division, Government of Bangladesh. MGD: Bangaldesh Progress Report. (2016). Millennium Development Goals (MDG): Bangladesh Progress Report. Dhaka: General Economics Division (GED), Bangladesh Planning Commission/ Government of the People's Republic of Bangladesh. Opel, B. A. (2012, January-February 31). Faecal sludge management in Bangladesh: an issue that needs urgent attention, ASIA REGIONAL SANITATION AND HYGIENE PRACTITIONERS WORKSHOP, Dhaka, Bangladesh: Bill & Melinda Gates Foundation.
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Strauss et al. (2002). Economic Aspects of Low-cost Faecal Sludge Management, Switzerland: EWAGE and SANDEC. Strauss et al. (2002). Fecal Sludge Management in Developing Countries: A planning manual, Swizerland: EWAGE and SANDEC. Wong et al. (2001). Co-composting of soybean residues and leaves in Hong Kong, Bioresource Technol, 76, 99–106. WSP. (2012). Economic Impacts of Inadequate Sanitation in Bangladesh, Water and Sanitation Program, Dhaka: www.WSP.Org, Retrieved from http://www.wsp.org/sites/wsp.org/files/publications/WSP-ESI-Bangladesh-Report.pdf Yousuf and Waled. (2011). A Study on Situation Analysis and Business model development of Faecal Sludge Management of Faridpur Municipality, Faridpur: Practical Action, Bangladesh and WaterAid Bangladesh.
SUMMARY: On Site Sanitation (OSS) systems are the predominant form of excreta disposal installations in urban centers of industrializing countries. In broad sense it is called Faecal Sludge Management (FSM) deals with the management of sludge from OSS facilities while wastewater management deals with sewered sanitation. In developing counties like Bangaldesh FSM is practiced by some areas where better sanitation has achived. Kushtia Municipality in Bangaldesh is practicing FSM from November 2012 from the initiation of the project. The paper aims to find the overall FSM situation in Kushtia Municipality by FSM toolbox and evaluates the end product namely compost by combining both dewatered Faecal Sludge (FS) and Organic Solid Waste (OSW). The research emphasized on capturing relevant information and necessary sample collection for the fulfilment of the objectives. Through the “FSM Toolbox” the situation of FSM chain in Kushtia Municipality is fair to excellent and the end product known as compost is harmless and usable for cultivated zone. Although the knowledge of the FSM and FS’s resuing is better known among local peoples in Kushita, proper steps should be engaged for better FSM practice.
1. INTRODUCTION As many of the developing countries are moving towards increased sanitation coverage, the issue of safe handling of sludge has emerged as an important and challenging issue of concern. In the city, this challenge is even more acute due to the factors like high population density, rapid and unplanned growth, inadequate and often inaccessible service provisions. In cities where most households practice on-site sanitation, the emptying of septic tanks or pits, and transport of sludge to a safe dumping site for treatment becomes an emerging need (Opel, 2012). There is no doubt that if safe disposal of sludge is not ensured, gains achieved by increased sanitation coverage cannot be realized. Faecal sludge management (FSM) deals with on-site sanitation systems, while wastewater management is concerned with sewered sanitation. FS may be treated in separate treatment works or co-treated with sludges produced in wastewater treatment plants (Strauss et al, 2002). Research suggests that improved excreta management could reduce the diarrhoeal morbidity by 36 percent (Carr, 2001). Sludge management is usually limited to a de-sludging service that
Proceedings Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium/ 2 - 6 October 2017 S. Margherita di Pula, Cagliari, Italy / © 2017 by CISA Publisher, Italy
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
is provided by municipal agencies or the private sector, proper solutions for sludge disposal are generally lacking. However, in urban areas the negative impacts on the urban environment become too highand actions have to be taken (Strauss et al, 2002). In urban areas of Bangladesh, the excreta disposal situation is very alarming. Faecal matter from either open defecation or from on-site sanitation (OSS) installations such as pit latrines, septic tanks are discharged indiscriminately into drainage system, low lands, rivers etc (Yousuf and Waled, 2011). Along with the sludge collection, the disposal of the collected sludge is also a big challenge. It is neither put in a trenching ground nor treated rather it is a common practice in the urban areas as well as rural areas to disposenof in drains or in water bodies making the whole environment a havoc. Conventional sewerage system is absent in all urban areas except Dhaka where only 25 percent of the population is served by a sewer network (GoB, 2011). This paper presents the findings of a situation analysis of the existing FSM system in the town of Kushtia, Bangladesh. Then it goes the solution of the end product made from both dewaterd Faecal Sludge (FS) and Organic Solid Waste (OSW).
2. LITERATURE REVIEW 2.1 Country Sanitation Context Sanitation is still one of the biggest challenges for Bangladesh although it has made some good progress in increasing sanitation coverage over the past 25 years. In Bangladesh, levels of access to sanitation are relatively high. According to Millennium Development Goals (MDG) 2015, Bangladesh has a remarkable achievement by rapid drop of open defecation from 33% in 1990 to 6% in 2009, which ultimately reached to 1% in 2015 as reported in the country report on Sanitation (MGD: Bangaldesh Progress Report, 2016). However, in most secondary towns there are no sewers at all, with all the residents relying on on-site sanitation combined with faecal sludge management practices. In most cases there is hardly any effective or safe collection, transportation, treatment or disposal of sludge. Much of it ends up in water bodies or polluting nearby land. The World Bank estimates the economic costs of poor sanitation in Bangladesh total $4.2 billion each year. This was equivalent to 6.3 percent of Bangladesh’s GNP in 2007, or $29.6 per person per year (WSP, 2012). 2.2 Use of FS as a soil Conditioner/ Compost There are a wide range of FS treatment technologies that can be combined in many different ways. All treatment processes result in endproducts which are either treated further, disposed of, or harnessed in some way for resource recovery. The use of FS as a soil conditioner can range from deep row entrenchment of untreated FS, to bagged compost that is sold as a commercial product for household level use in horticulture. Moreover using as a soil conditioner it has an adavantage over using chemical fertilizer in farming lands. Controlled biological decomposition process of organic wastes into humus, a soil-like material is known as composting. Composting is nature's way of recycling organic wastes into new soil used in vegetable and flower gardens, landscaping and many other applications. Biological treatment is a very economical natural treatment process for organic solid wastes. In practice, the main biological process applied is generally composting. Composting is the biological degradation of highly concentrated biodegradable organic wastes in the presence of
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
oxygen (aerobically) to carbon dioxide and water, whereby the biologically generated waste heat is sufficient to raise the temperature of the composting mass to the thermophilic range (50 to 65oC). The final product of composting is a stable humus-like material known as compost. 2.3 FSM Situational Assessment Toolkit FSM Situational Assessment Toolikit (SAT) is a systematic process to assess the present situation of FSM in any designed location and help users to take part in FSM oriented options and programs. It also helps to identify the problems and possible solutions with the aim of better FSM situation in the future (FSM Toolbox, 2015). 2.3.1 What is a SAT Tool § §
Excel based tool Provide questions to assess and Identify FSM city existing situation for entire FSM service Chain
§ Report graphical summaries for city FSM status and challenges and problems – Dashboard
1&2
Figure 1. FSM situation dashboard
Figure 2. Steps involved in the situational assessment tool
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
2.4 Description of study area Kushtia zila comprises of only the sadar sub-division of former Kushtia zila. It is generally believed that the zila Kushtia might have derived its name from the word "Kushta" meaning Jute which was abundantly grown in this area. It lies between 23°42´ and 24°12´ north latitude and between 88°42´ and 89°22´ east longitudes. The total area of the district is 1621.15 sq.km (625.93 sq.miles). The annual average temperature of this district varies from Maximum 37.8ºC to minimum 11.2ºC and annual average rainfall is 1467 mm. Moreover some basic information regarding Kushtia Municiapality has shown in the following table. Table 1. Basic information regarding Kustia Municipality, Bangladesh Name of the Municipality Name of Mayor Municipal Area No. of Ward No. of Mouza included Total no. of Municipal Staff Population No. of Household No. of Holding
: : : : : : : : :
Kushtia Municipality Anwar Ali 42.79 sq.km 21 19 166 3,75,149 83,926 33,936
Figure 3. Location of Kushtia Municipality, Bangaldesh
2.5 Description of existing Faecal Sludge Treatment Plant (FSTP) § § § § §
From the observation, configurations of the existing FTP are summarized below: There are 2 units of sludge drying bed ( 2 beds x 6.05 x 10.2x 0.8 m as W x L x H).( Fig.4 and 5). The 2 inlet chambers are 2 chambers x 2.15 x 6.05 x 0.5 m. Installation of media in treatment beds is shown in Section plan drawing. The perforated tubes were also installed at the bottom of tank and connected to effluent tank. Hydraulic loading rate is 0.3 m3/m2 (by calculation) Timing to get dried sludge in each batch is depended on weather. It is may be more than 10 days or more than 20 days during raining season.
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
§ §
Maximum feed is 70 trips per bed (700L/trip) After sludge dried, it will be removed by manually.
Figure 4. Plan view of Existing FSTP in Kushtia
Figure 5. View of Existing FSTP in Kushtia
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
3. MATERIALS AND METHODS 3.1 Data collection and compilation The study applied both qualitative and quantitative methods for better understandings of varoious aspects and components relating to sludge management issues. For relevant information and data, a quessionaire was conducted through conservency department, City Planner, Assistant Engineer (water), Executive Engineer of Kushtia Municipality, Soil Research and Development Institute (SRDI), Kushtia office. After Collecting the information, FSM Toolbox specially SAT tool was applied to assess present FSM situations. The tool contains three different types of questions: Yes/In-process/No, Open-ended, and multiple-choice questions. Firstly, questions that can be scored are identified i.e. Yes/In-process/No and certain multiplechoice questions. Then according to questions, answers were put in the excel sheet and scores and were auto calculated by weighted average index. For three-option answers, the score of 1 was given to the option ‘Yes’ (‘best possible answer’), the score of 0 was given to the option ‘No’ (‘with considerable scope of improvement’) and the score of 0.5 was given to the option ‘In process’ (‘with a moderate scope of improvement’). Weighted Average =∑(Score* weight)/ Total Weight The assessment of the FSM situation was carried out based upon the answers that users select especially from Yes/In-process/No and from certain multiple choice questions, as those questions led to scores which will be reflected in the form of colors as an output of the assessment. Therefore, the answers of such questions have been observed in the form of reports in Dashboard 2 and the detailed information on the range of scores were also observed by clicking the information button in Dashboard 1. 3.2 Sample collection and laboratory tests A co-composting process was done in KUET campus, Khulna for gaining scientific and technical knowledge, skills and experiences in co-composting of OSW and FS. The random samples were collected from the existing treatment plant where faecal sludge is being dumped, from septic tank as well as from pit latrine. Then the FS was first pre-treated by dewatering in drying beds before co-composting with sorted OSW. Before that, the samples were taken for laboratory tests like Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Temperature, Nitrate-Nitrogen, (Ortho) Phosphate, Water content, Total and Volatile Suspended Solids, Total Coliform, Faecal Coliform, Sludge Volume Index (SVI), Electrical Conductivity and Alkalinity. Paralelly both a simple heap made with wooden frame and wire mesh (6 ft×4ft×2ft) and a drying bed of 8ft×8ft was made in KUET campus for further process. Dewatered FS was removed from the beds and mixed with sorted OSW. Then for composting, following tests were conducted: pH, Organic Carbon, Nitrogen, Phosphorus, Potassium, Sulphur, Lead, Calcium, Nickel, F.C, Helminthes eggs etc. In addition, relevant primary, secondary data were reviewed, pits and septic tanks emptying works were shadowed to generate accurate information.
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Figure 6. Sample Collection from a pit latrine in Kushtia Municipality, Bangladesh
Figure 7. Laboratory test of sample in KUET, Bangladesh
4. RESULTS AND DISCUSSION 4.1 FSM sevice chain FSM scorecard is the overall scenario of the FS management for any particular region. Kushtia FSM scenario is fair to excellent where different colors indicate the specific condition of the respective situation. From scorecard it is clear that, the general condition is fair (0.45-0.55). FSM chain is under excellent category where Containment is within range of 0.68-0.78, Emptying is within range of 0.79-0.89, Transportation is within range of 0.79-0.89, Treatment is within range of 0.68-0.78 and finally Reuse is within range of 0.79-0.89. The score of excellent indicates that, FSM situation is under low risk category and also suggest that the service delivery is largely on place. Figure 8 and 9 shows the detailed FSM scorecard and evaluates the overall FSM performance.
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Figure 8. FSM Service Chain Scorecard (Overall Situation of the FSM in Kushtia Municipality, Bangladesh)
Figure 9. FSM Chain Scorecard (Score and its meaining)
4.2 Test results of the FS and compost The visual characteristics of the compost made for experiment weighed 2.82 K.G. where the initail weight of the compost was 5.00 K.G. So the reduction in weight was about 43 % indicates that the combination of FS and OSW combindly reduces the percentage of wastes by making a reuseable material. Moreover, color, odor and moisture that was observed is satisfactory which depend on the local climate, constituents of the OSW, local human nature, etc. prototype compost was dary gray in color, absence of foul odor, and dry in combination. Other physiochemical characteristics like pH was observed 8.3 which at the end of maturation level. The pH remained above 8.0through the composting which shows the alkaline character of the material. There also a high level of Electrical Conductivity (EC) was observed after the end of composting perid recorded as 8.09 mS/cm. It needs to be considered that a high conductivity could be due to dissolution of sodium chloride which is not beneficial to plants. This is especially important for application of thecompost in agriculture since high soil salinity may inhibit plant germinationand growth (Cofie et al, 2009).
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Total Volatile Solids (TDS) and Fixed Solids (FS) are respectively 25.24% and 74.76% and Total Solids (TS) found as 707797 mg/L. Total Organic Carbon (TOC) found as 14.64 % which is within the standard value (10-25%). Total Organic Nitrogen (TON), Nitrate Nitrogen and Total Kjeldhal Nitrogen were fonud respectively as 2.00 % which is within the limit of 0.5-4.00%, 0.4 mg/L and 140 mg/K.G. The C/N ratio was used by many authors as one of the indicators of compost maturity. However, it cannot be used asan absolute indicator of compost maturity due to its large variation that is dependent on the starting materials. Never-theless,Wong et al. (2001) it was found that, a value around or below 20 is satisfactory (Wong et al, 2001). Bangaldesh Ministry of Agreiculture set a value of standards for compost where the C/N ratio would be maximum 20:1 and it was found of our compost as 7.3:1. So the C/N ratio after maturation level satisfied the above suggested limits and is suitable for addition to soil. Other all nutrient parameters and heavy metals concentration are mentioned in the following table 2.
Figure 10. Finished product (compost) (left: after screening and sorting, right: before screening and sorting)
The results of bacteriological analysis in compost found that, the most probable number of total coliform and faecal coliform were found respectively 1400 and 100 per 100 Ml of sample. On the other hand, nos of Helminth eggs was nill by observing through the microscope at 10x and 40x zoom level. Table 2. Shows the overall results of the compost with standard limits set by ministry of agriculture, Bangladesh for compost standards. Table 2. Basic parameters of the compost with standard limits Serial no 1 2 3 4 5 6 7 8 9 10 11 12 13
Characteristics Colour Odour pH Moisture (%) Total Volatile Solids (%) Fixed Solids (%) Total Solids (mg/L) Total Organic Carbon (%) Total Organic Nitrogen (%) C: N Nitrate nitrogen (mg/L) Electrical Conductivity (mS/cm) Total Kjeldahl Nitrogen (mg/ kg)
Result Dark Gray Absence of foul odour 8.3 29 25.24 74.76 707797 14.64 2.00 7.3:1 0.4 8.09 140
Standard Range* Dark gray to black Absence of foul odour 6.0 –8.5 Maximum 20 %
10-25 % 0.5 – 4.0 % 20:1 (maximum)
Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
14 15 16 17 18 19
Phosphorus (%) Potassium (%) Lead (ppm) Nickel (ppm) Sulphur (%) Total Coliform (mpn/100 ml)
0.5 1.8 27 7 0.1 1400
20
Faecal Coliform (mpn/100 ml)
100
21
Helminth eggs (nos/L)
0
0.5-1.5 1.0-3.0 Maximum 30 ppm Maximum 30 ppm 0.1-0.5 ≤1000, WHO guideline 1989
(*compost standards, ministry of Agriculture, Bangladesh)
5. CONCLUSIONS Although there is a business potential of the proper FSM in Kushtia, there is a mere absence of proper FSM service which indicates that, there is a widespread lack of understnding awareness about its health and envoronmental impacts as well as its economic value. The FSM sevice chain shows the green marks in every portion, but this study therefore highlights the importance of working at different levels and with different pilot approaches so that the successful working model can be scaled up. The composting of both FS and OSW with a mixing ratio of 1.3 contained better result and properly treated endproduct is a stabilised organic product that may be safely handled, stored and applied to land according to guidelines of Ministry of Agriculture, Bangladesh. Although composting is a proven technology to produce a safe to use soil amendment, the local market demand for compost products should be evaluated as compost frequently does not have a significantly high market value. FS are disposed of or used in agriculture untreated in the majority of cases, creating enormous health risks, eye and nose sores and water pollution. From this point of view Kushtia Municipality FSM is effective and need more assistance for its sustainability.
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Sardinia 2017 / Sixteenth International Waste Management and Landfill Symposium / 2 - 6 October 2017
Strauss et al. (2002). Economic Aspects of Low-cost Faecal Sludge Management, Switzerland: EWAGE and SANDEC. Strauss et al. (2002). Fecal Sludge Management in Developing Countries: A planning manual, Swizerland: EWAGE and SANDEC. Wong et al. (2001). Co-composting of soybean residues and leaves in Hong Kong, Bioresource Technol, 76, 99–106. WSP. (2012). Economic Impacts of Inadequate Sanitation in Bangladesh, Water and Sanitation Program, Dhaka: www.WSP.Org, Retrieved from http://www.wsp.org/sites/wsp.org/files/publications/WSP-ESI-Bangladesh-Report.pdf Yousuf and Waled. (2011). A Study on Situation Analysis and Business model development of Faecal Sludge Management of Faridpur Municipality, Faridpur: Practical Action, Bangladesh and WaterAid Bangladesh.
