Publications

Over the past two decades Vietnam has achieved remarkable advances in its economic development, progressing from least developed country status to lower middle income, thus becoming one of Southeast Asia’s most rapidly industrializing countries. Vietnam’s geographical position, bordering with China, Laos and Cambodia on the West and the South China Sea on the East, has enabled larger trade of goods throughout the region. However, these results at the national level conceal significant geographical disparities and inequalities between the rural and urban inhabitants. Data indicates that poor people’s access to quality services in the areas of health, water, sanitation and education is still a concern.

This research proposed to analyze the impact of the Biogas Division Project in Vietnam, created in 2003 in collaboration with MARD and SNV. The study aimed at evaluating quantitative figures of biogas masons activity levels. Construction levels indicated that masons are extremely busy despite the seasonal effects of the job. Digester demand is on the high rise. 97% of masons said that they would continue construction levels if the program ceased from existing, confirming and ensuring the self-sufficiency of the biogas sector, something which SNV and BPD aimed to establish. Conclusively, BPD is recommended to upscale and sub-group mason business training programs to better adhere with their mason profiles. Improving training and educational programs will allow for the possibility of concrete SME development within a economically sound Biogas sector.

Biogas Project Division has conducted this research, which aims at assessing actual effect of available products potentially influence methane production and to give advice of how to utilise the products best to users. 

There are biogas digesters that do not produce gas or gas production is little or it takes long time for gas production with low gas quality. This happens more frequently in winter and in areas with low temperature. An explanation from scientific point of view is that fermentation and methane production are affected by different elements like anaerobic environment, temperature, pH degree, input contents (ratio of C/N, powder substance), toxics and retention time. The change of one or all of these factors somehow will make a significant impact on fermentation and methane production of biogas digester. On the other hand the incorrect operation of households also influences the process of gas production. 

Being faced with such situation, scientists, organisations and individual have studied and promoted products that can strengthen fermentation for organic digestion and methane production in biogas digester. All these products are promoted and advertised with highest efficiency in facilitating methane production. Nevertheless, no comprehensive evaluation of these products was conducted so that users can rely on and further promote them. 

The research products: Penac G, Microphot, and Bicat were used for testing the effect on digestion, fermentation and methane generation. Specific tests were aims at CH4, H2S, CO2, pH, COD, BOD5 and SS. Research and sampling methods are explained and a brief conclusion is provided.

The objective of this experimental study is to estimate the effects of using bio-slurry in fish ponds and identify methods (e.g. diet of bio-slurry and pellets; substitution rate of bio-slurry for organic manure; substitution rate of bio-slurry for chemical fertiliser; points of attention when using bio-slurry for fish farming) for using bio-slurry for commercial fish pond and benefits for this practice. 

Other objectives: to calculate economical, environmental and safe product benefits; develop manual on using bio-slurry for commercial fishpond.  The use of bio-slurry shows good influence to growth of fish. Especially, Grass Carp and Black Carp which prefer living in clean water, show significant growth when using bio-slurry. The survival rate was the lowest considering treatment with the use of pig manure (85,83%). The highest rate of survival is 89,29% in treatment with a mixture of bio-slurry and pellets. Common Carp shows highest survival rate of 94,15% and lowest one is in Grass Carp being 78,61%.  

The feed converting rate shows considerable increase during the experiment period, that is lowest at 1.42 in method of mixing bio-slurry with pellets and highest at 1.55 in control. Phytoplankton in pond using bio-slurry is abundant, in which 222 species of algae were defined.  Zooplankton was also isolated with 26 species in 3 groups named Cladocera with 8 species holding 30,76%, Copepoda and Rotatoria with 9 species for each occupying 34,62 %. Epidemic diseases happened in Grass carp and Black carp. Epidemic disease happened strongly in the trial adding pig manure.