KNOWLEDGE AND PRACTICE OF FARMERS IN USING LIVESTOCK WASTE IN HANAM PROVINCE FOR BIOGAS GENERATION T IN 2015
Luu Quoc Toan1,2*, Nguyen Mai Huong2, Hung Nguyen Viet2,3, Pham Duc Phuc2
ABSTRACT
The objective of the study was to assess farmer’s knowledge and practices in the use of biogas generation to treat livestock waste.
We conducted a study of 442 farmers who have biogas plants in their households in Hoang Tay and Chuyen Ngoai commune, Kim Bang Hanam province in 2015. The study results show that farmer’s knowledge and practices of using biogas was limited. In particular, properly knowledge of farmers about biogas operation, and safety of using biogas were 1.0 – 33.1%, and 16.4 – 72.9%, respectively. Proper practice of the farmers about observation of waste input loading, and observation of output biogas wastewater were 6.8 - 35.6%, and 20.1 - 36.3%, respectively. Our fi ndings suggested that appropriate education and communication programs are needed to improve the knowledge and practices of farmers of biogas operation at household level.
Keywords: knowledge, practice, biogas, Hanam, Vietnam
INTRODUCTION
Biogas generation is a method if livestock waste treatment based on anaerobic digestion that eliminates most of the pathogens in livestock waste, provides useful gas, and reduces environmental pollution. In Vietnam, biogas use has been increasing since 1990s. In 2013, MARD estimate that 8.7% of livestock households had a biogas plant1. Using biogas has many positive aspects of the economic and environment benefi ts, but the process has some limitations. In particular, inappropriate biogas operation leads to inadequate waste treatment and the survival of pathogens.
Concentration of E. coli, Salmonella in wastewater have just reduced 1-2 log10 by biogas treatment. G. lamblia, C. parvum has detected in wastewater of pressure tank
1. Nutrition and Food safety Dept., Hanoi School of Public Health
2. Center of Public Health and Ecosystem Research (CENPHER), Hanoi School of Public Health 3. International Livestock Research Institute (ILRI)
* Corresponding author: Luu Quoc Toan, Nutrition and Food safety Dept., Hanoi School of Public Health. Email: [email protected]
with high prevalence (48.8% and 22.2%, respectively)2,3,4.
The report of Biogas Programme for the Animal Husbandry Sector in Vietnam (BPOVN) there are some limitations in the biogas operations of farmers, with approximately 90% of farmers not loading the proper volume of wastes5,6,7. In practice waste loading is an important factor that affects the performance of biogas generators8,9. BPOVN have provided educational materials with practical knowledge about using biogas for farmers who were participate in their program. They estimate that this is 20% of households with biogas in the country10. Education programs about the use of biogas is limited for households outside the BPOVN.
There is a need for the provision of information about the correct operation of biogas plants.
The transdisciplinary approach is likely to be adopted widely in the intervention program, particilar intervention programs to change the agriculture and rural issues. Community priorities should be determined by local people. Then community problem will be solved by knowledge of scientists and practical experience of local people co-operation. It is core competency of the ecosystem approach to health.
The research was carried out as a component of an interdisciplinary intervention program to improve knowledge and practice of using biogas for farmers in Hanam Province. The objective of the study was to assesse farmer’s knowledge and practices in the use of biogas to treat livestock waste before intervention.
METHODS
The research sites were Hoang Tay and Chuyen Ngoai communes in Hanam province during
2015. Farmers who had biogas plants on their property were invited to participate in the research. This project was a cross-sectional study that was the fi rst component of commune- wide intervention program to improve the processing of biogas. The recruitment of farmers is described in the BPOVN’ survey of 20116. TThe clusters used in the study were the communes Hoang Tay (n=199) and Chuyen Ngoai (n=200) commune. They were interviewed using a structured questionnaire.
Main topic of the questionnaire was the farmers’ knowledge and practices related to biogas production. The knowledge component focused on the operation, maintainance, and safe use of the biogas plant. The practice section included questions on using personal protection, monitoring the waste input and monitoring the wastewater output. After collecting, the data was entered by Epidata software then was analysised by SPSS software.
The study received approval from the Ethical Review Board of Hanoi School of Public Health, No. 041/2013/YTCC-HD3.
RESULTS
The 399 farmers, representing 399 households that produce biogas in Hoang Tay commune and Chuyen Ngoai communes in Hanam, were 51.6% male and 48.4% female. The age range of the participating farmers was 19-87 years old of age, although most were in the 40-50 years age range. A total of 88.5% of the farmers had fi nished junior high school and the remainder a lower level. The farmers’
knowledge and practices in the use of biogas plants are presented below.
The proportion of farmers fully knew 3
common types of waste (animal manure, food waste, dead animals), that can be loaded into the biogas plant,was 78.5%. Knowledge of the farmers about properly volume of loading waste per day, suitable ratios for dilution of the waste by water when loading, retention time of the waste in the biogas digester by local climate were 1.5%, 6.0% and 1.0%, respectively. The proportion of people, who knew the mechanism of waste treatment in biogas (the anaerobic fermentation), was 33.1% (Table1).
Table 1. Farmer’ knowledge about using biogas plants
Categories of farmers’ knowledge in using biogas
Correct answer Frequency % Biogas operational (N=399)
Type of waste to be loaded 34 8.5
The mechanism of waste treatment in the plant 132 33.1
Required retention time 4 1.0
Appropriate quantity of waste to be loaded daily 6 1.5
Appropriate rate of water usage 24 6.0
The function of the gas meter 15 3.4
Biogas plant maintenance (N=399)
Drawbacks of scum 22 5.5
Treatment biogas scum 4 1.0
Drawbacks of sediment 20 5.0
Treatment biogas sediment 271 67.9
Among the 399 participating farmers, there were 22 persons (5.5%) who had knowledge about the harmful effects of surface scum that can be created during the operation of the biogas digester, 4 persons (1.0%) knew how to treat scum and avoid creating surface scum in the digester tank. The proportion of participating farmers, who had knowledge of the harmful effects of sediment and sediment treatment, was5.0% and 67.9%, respectively (Table 1).
Assessment of participating farmer’s knowledge on safety practices for using biogas, the proportion of farmers, who knew about bacterial hazard’s in the biogas plant’s wastewater, and asphyxiation and explosions awareness of the biogas product, reached 65.7% and 72.9%, respectively. The proportion of participating farmers who knew about safe management asphyxiation and explosions rich of biogas product in the home environment, and safe solutions by correct digester’s maintenance were 16.4% and 42.1%, respectively, very low fi gures (Figure 1).
Table 2. Farmer’s practice in using biogas
Categories of farmers’ practices in using a biogas plant
Correct answers
Frequency %
Monitoring for input waste loading (N=399)
Using agas meter 142 35.6
Washing the barn after a gas cooktop 108 27.1 Dry dung cleaning before washing barns 100 25.1
Estimated amount of suitable water 27 6.8
Monitoring for output biogas wastewater (N=399)
Check the water level of pressure tank 80 20.1 Check the color of wastewater in pressure tank 145 36.3 Check the smell of wastewater in pressure tank 113 28.3
Figure 1. Farmer’s knowledge on safety for using biogas (N=399)
Among the participating farmers 35.6 % had installed a gas meter in their biogas system.
About one quarter (27.1%) of farmers said the fi rst time of cleaning the barn (unloading waste from biogas production) was performed after they burned the biogas for cooking. While cleaning livestock barn, the proportion of participating farmers, who cleaned dry manure fi rst, and correctly estimated the appropriate volume of water for cleaning was 25.1%, 6.8%, respectively (Table 2).
The results also showed that the participating farmers, who regularly observed smell, color, and level of wastewater in the biogas pressure tank was 28.3%, 36.3%, and 20.1%, respectively (Table 2).
The proportion of participating farmers, who had used masks, gloves, and boots while working with biogas and its products, reached 49.1%, 32.8%, and 72.2%, respectively.
Meanwhile, the proportion of participating farmers using fully three protective equipment that were 23.8% (Table 2).
DISCUSSION
The participating farmers’s knowledge about operating biogas plants
In Vietnam, using a biogas generator at household level to treat livestock waste has grown to 8.7%
of households that have livestock1. Applying biogas techniques in agricultural should be accompanied by improving the farmers’
knowledge to ensure effi cient and safe use of biogas. The mech anism of livestock waste treatment by biogas is anaerobic fermentation which produces methane and other gases8. In this study, nearly one third of participating farmers had correct knowledge about the mechanism of the biogas plantsoperation. In the biogas plant operation, the correct amount of waste to be loaded each day is important and should be consistent with with the design of the biogas system. Normally, the volume of waste loaded daily into the biogas digester is approximately 25kg per m3 per day. This depends on the local weather and the type of waste available.
Hanam is a province belonging Red river delta so retention time in the biogas generator is approximately 40 days8,9. However, it seems that most of the farmers in this study do not have this knowledge. The proportion of farmers who understand about the volume of waste, retention time, and suitable dilution ratio water to waste, was very low. They reached 1.0%, 1.5%, and 6.0%, respectively.
The creation of surface scum and sediment are common phenomenon during the operation of biogas plants. They lead to decrease performance of the digester and can create some hazards8,9. Participating farmers’ knowledge of how to handle sediment in biogas was relatively high (67.9%). However, their knowledge about the harmful effects of sediment and scum, and Figure 3.2. Farmer’s practice in using personal
protection equipements (PPE)
how to handle sediment and scum were very low (1.0 – 5.5%). They tended to use too much water when cleaning their livestock barns. Using too much water is the cause of the formation of surface scum in digester tank8. This situation was mentioned in the BPOVN’s survey in 2013.
The proportion of households discharging too much water with livestock excrement when the barn was cleaned was 81%7.
Knowledge of safe operation is very important when using biogas to reduce explosion and asphyxiation risks. In this study, participating farmers had relatively good knowledge about the risk of explosion and asphyxiation from biogas (72.9%). However, their knowledge about the safe handling in the case of leaking was poor (16.4%) and managing biogas asphyxia cases was poor (42.1%) The farmers were also assessed for knowledge of other hazards of biogas production, including bacteria in the wastewater of biogas production. Previous studies have shown that biogas digesters only partially reduce the level of pathogens in waste3 4. In this study, 65.7% of participating farmers knew about these dangers.
The participating farmers’s practice about operating biogas
The keys to biogas digester operations are waste loading and retention time8,11. Retention time is primarily determined by the ambient temperature. The study results showed that farmers were not good in ensuring appropriate water and waste volumes were used. The total volume of water and waste usually exceeded the functional design of the household biogas plants. The proportion of farmers who had the skill to estimate properly water and clean dry manure quantities during the cleaning of shelters was only 6.8% and 25.1%, respectively.
This rate is lower than the BPOVN Report.
In 2012 and 2013, the proportion of BPOVN farmers did not estimate water to clean cage and loaded into biogas that reached 87.6% and 81%, respectively5,7. The BPOVN farmers due to the training that maybe cause the difference.
In fact, the proportion of BPOVN households are not big that compare to the total number of general biogas households with biogas (20%)10. In addition, there was a very large proportion of BPOVN farmers that did not participate in their training (85% in Hanam)7.
Practice for monitoring of wastewater quality that is also essential to make adjustments waste loading. These monitoring factors include level, color and smell of wastewater in pressure tank.
Standards for wastewater biogas sector is no stench, no larvae and maggots12. In this study, the farmers have not focused to perform the monitoring practice on wastewater of biogas.
Proportion of the farmers inspect the color, and smell of sewage in pressure tank that reached 36.3% and 28.3%, respectively.
The effects of animal waste treatment by biogas is good but it have been not thoroughly in many cases3,2. Therefore, using protectors is required when performing activities of cleaning and using biogas products for agriculture. In this study, the farmer have not focused on the use of gloves (32.8 %) then the overall assessment of the farmers in using full protection tools (mask, gloves, boots) was low (23.8 %).
Situation of farmer’s knowlegde and practice in using biogas that orient the community participatory intervention program
Research results showed that lack of properly knowledge and practice of farmers in using biogas is real situation at the household. In
Vietnam, biogas is efective livestock waste treatment. However, offi cial communication resources, that was used to guide farmers, have been not popular. A small percentage of households, which were participated in the biogas program for the livestock sector in Vietnam, received the training of this program.
However, most of them have not attented these course or not recorded training information.
Then it suggest to improve guidelines and appropriate communication methods that help raising the knowledge and practice of farmers in using biogas. This study have been a part of such intervention program. It is call the transdisciplinary and community participatory approach or Ecosystem approach to health.
The limitations of research
Knowledge and practices of farmers in using biogas are affected by many factors, especially the source of information and guidance services to use. In this study, the research results just based on description. Most orientation information is based on the theorical of biogas operation. This study have not evaluated the relevant factors that may lead to the unproperly status of knowledge and practice of farmers in using biogas, particularly in relation to household economic benefi ts.
CONCLUSION AND RECOMMENDATION In the study sites, knowledge and practices of the farmer in using biogas to process animal waste that is limited. In particular, the proportion of the farmers, who have had right knowledge and right practice of estimating properly daily loading water and waste for household biogas, was very low. This is one of the key factors effect to processing of biogas to treat animal waste thoroughly.
The fact demand to improve and communcate the appropriate communication program to improve the knowledge and practice of farmers in using household biogas. In particular, the communication program should be focused on guiding people in controlling the total amount of water and waste that will be loaded daily to biogas.
ACKNOWLEDGEMENT
We would like to thank community members who participated in the research. We also would like to thank our fellow FBLI research team and the volunteers. Special thanks to IDRC support was provided the funds and helps through the project “Using an Ecohealth approach for better human and animal waste management in Hanam Province, Vietnam”.
REFERENCES
1. Ministry of Agriculture and Rural Development.
Study and propose solu ons to the ins tu onal and policy environment in livestock management.
2013; h p://x m.mard.gov.vn/Site/vi-VN/76/
tapchi/69/106/5580/Default.aspx. Accessed 2-9, 2015.
2. Huong L Q, Madsen H, Anh L X, Ngoc P T,
Dalsgaard A. Hygienic aspects of livestock manure management and biogas systems operated by small-scale pig farmers in Vietnam. Science of The Total Environment. 2/1/ 2014;470–471:53-57.
3. Huong L Q, Forslund A, Madsen H, Dalsgaard A.
Survival of Salmonella spp. and fecal indicator bacteria in Vietnamese biogas digesters receiving pig slurry. Interna onal Journal of Hygiene and Environmental Health. 9// 2014;217(7):785-795.
4. Thu L T et al. Assess health risks from exposure to sewage biogas in three communes in the province of Hanam in 2014. Master thesis; Hanoi School of Public Health; 2014.
5. Biogas Programme for the Animal Husbandry Sector in Vietnam. Survey of biogas users in 2012. 2012.
6. Biogas Programme for the Animal Husbandry Sector in Vietnam. Survey of biogas users in 2010- 2011. 2011.
7. Biogas Programme for the Animal Husbandry Sector in Vietnam. Survey of biogas users in 2013.
2014.
8. Teodorita Al Seadi DR, Heinz Prassl, Michael Kö ner, Tobias Finsterwalder, Silke Volk, Rainer Janssen. Biogas handbook. University of Southern Denmark Esbjerg 2008.
9. Giao H K. Using biogas handbook version 5. 2010.
10. Giao H K, Nguyet D T N. Proceedings of 10 years - Biogas Program for the Animal Husbandry Sector in Vietnam. 2013.
11. Roubík H, Mazancová J, Banout J, Verner V. Ad- dressing problems at small-scale biogas plants: a case study from central Vietnam. Journal of Cleaner Produc on. 1/20/ 2016;112, Part 4:2784-2792.
12. Khai N Q. Small scale biogas plant. 2002.