Page 23 - Agricultural innovation

Wastewater control measures are implemented using a variety of techniques. The first is to reduce
the volume of waste treatment in biogas tanks through the establishment of physical nets to retain
solid residues in the water collection ditches.
The solid residue in the water is separated from the manure collection pits at high altitude and
transferred to and run through the tank using electrochemical technology of inert and soluble
electrodes to remove solids by electrochemical flotation; quickly reduce the amount of pollutants
entering the biogas tank; increase the operating life of the biogas tunnel. Electrochemical technology
can remove heavy metals from wastewater while this cannot be done by using only microbiological
measures in biogas tank. Automatic suction system and blowdown valve increase the efficiency of fresh
manure collection.
Wastewater after coming out of the biogas tank is added with EM solution and put into storage
ponds (anoxic, aerobic, dehumidifying and water storage) before being discharged into the environment
or reused.
Measures to treat solid waste are arranged at the disposal site to make fertilizer for plants.
In the future, if biogas is generated a lot, it can form a place to supply more from biogas for
drying materials.
Thus, with these integrated solutions, this Tri Dung pig farm has met the requirements of the
standards set out by the Decision No. 62 of the Ministry of Natural Resources and Environment.

3.5.3. Opportunities and challenges
With a system of basic solutions in controlling air pollution, water pollution and solid waste, this
model of pig farm has created an opportunity for widespread application to livestock farms. With the
technology of wastewater treatment by electrochemical measures, it can be applied to aquaculture
models through the treatment of water sources before and after farming.
This waste treatment system will have conditions to be widely applied on large-scale farms as
Vietnam is moving towards safe and ecological agriculture and promoting strict monitoring on
wastewater standards in the livestock industry.
However, this model requires certain investments in machinery and equipment, construction of
settling ponds, etc., so it can be difficult to apply to small-scale pig production when the financial
resources of households are relatively limited.

3.5.4. Conclusions
The waste treatment model at Tri Dung Farm, Huong Ho commune, Huong Tra district, Thua Thien
Hue province has combined biophysical achievements to solve not only air pollution, wastewater
and solid waste but also improve meat quality and increase livestock production, reuse part of
wastewater after treatment as well as the volume of pig manure that can be treated and reused as
fertilizer for crops.
The equipment produced at the company has different capacities suitable for processing scales from
40–100 m /h and will be suitable for different farms. According to calculations by company experts,
3
the equipment selling price for 1 hectare is about 320 million VND and the cost of water treatment is
reduced to 1,200 VND/liter of water compared to 1,500–1,800 VND/liter of water for the treatment
method using chemicals that are harmful to the environment.
This model applies not only to pig production but can also be extended to other livestock industries
even suitable for water treatment for aquaculture.

16 ©2023 NARDT