Potential from WtE
Beginning operations at the end of last April, Go Cat WtE plant (Binh Tan district, Ho Chi Minh City) has processed approximately 500 tonnes of industrial waste, while generating 7MW of electricity into the national grid.
The plant is operated by a system of pre-processed garbage equipment, such as primary and secondary cutting equipment, industrial garbage pressing equipment, gasification furnaces, syngas containers, and three syngas generators with a capacity of 550kVA each.
According to the Ho Chi Minh City Urban Environmental Company, Go Cat landfill, which covers an area of 25 ha, operated from the end of 2000 to July 2007. Since becoming inactive, there was over 5.3 million tonnes of rubbish at the landfill.
At the beginning of 2017, Ho Chi Minh City Urban Environmental Company, in coordination with the Hydraulic - Machinery Company, made a proposal to the Ho Chi Minh City People's Committee for an experimental Go Cat WtE project to be constructed in order to convert solid waste and industrial garbage into green energy (energy-from-waste) on an industrial scale, connecting to the national power grid (medium voltage) at 3,500V or 6,600V.
Nguyen Gia Long, Director of Hydraulic - Machinery Co., Ltd, said that with WtE it is possible to treat solid waste without classification, which is a suitable factor for Vietnamese waste and also a different factor compared to several other current technologies. The nature of WtE is to convert solids to gaseous matter, through using heat in anoxic conditions, so that secondary pollution does not occur.
In addition, the WtE investment rate is only one third of that of foreign technologies, with low operating costs; the waste is disposed thoroughly without the need for conventional burial methods; the automated, closed lines help to minimise contact between humans and garbage during operation; and there is also no smoke or dust emissions into the environment. It is expected that in the near future, WtE will be piloted in Phu Quoc (Kien Giang).
Previously, in Hanoi on April 24, Vietnam’s first WtE processing plant officially began operation in Nam Son commune (Soc Son district). The plant utilises Japan's advanced WtE technology with a capacity of 75 tonnes per day and generates 1.93 MW of electricity. The whole project covers an area of almost 17,000 m2 with a total investment of over VND645 billion, of which non-refundable aid from Japan’s New Energy and Industrial Technology Development Organisation (NEDO) accounts for VND472 billion and the remaining is reciprocal capital taken from the Hanoi budget.
Japanese Hitachi Zosen Company provides all of the plant’s equipment and technology transfer, while Sunny Vietnam Co., Ltd. was responsible for the installation. Hanoi Urban Environmental Company (URENCO) performed the construction of the related technical infrastructure items and put into operation the factory’s technology chain.
According to Ngo Minh Tien, Director of Nam Son WtE Burner, at present, under the strict supervision of the Japanese side through a modern online surveillance system, Nam Son plant operates consistently and efficiently, both economically and environmentally and is a potential opening direction for industrial waste treatment.
In order to support processing industrial waste into electricity, Vietnam Electricity Group (EVN) has invested in upgrading its power infrastructure to support WtE plants in connecting to the national power grid. The electricity price of these plants is currently at 7.28 cents/kW.
Stronger policy support needed
Stronger policies needed to back investment in waste-to-energy technology in Vietnam.
According to a representative from Hydraulic - Machinery Company, Go Cat WtE plant is operating stably, connected to the national grid without incident and the lighting system at the plant from the WtE source is effective.
However, hot and continuous rainy weather, in addition to a lack of warehouses and space to install water cooling systems to cool down the synthesis gas, has caused the spread of odours. To overcome this situation, the plant will install a cover for the equipment in the gasification area and an electrostatic filter system to prevent any smells dispersing. In addition, adjustments will be made for the gas supply system for generators to maximise the capacity of the machines, as well as installing an additional multi-fuel furnace system to provide enough gas for the generators.
The Ho Chi Minh City Department of Natural Resources and Environment assessed that, until now, electricity supply from the plant has been stable with convenient combustion and without any environmental issues. However, in the near future, it is necessary to take samples of exhaust gas to test factors such as dust, lead and heavy metals, as well as completing the installation of a filtration system or gas treatment to limit any smells, while developing ways to handle the different types of waste so that the plant will even be able to process hazardous waste.
The city’s department will propose various solutions and mechanisms to call for and create favourable conditions for domestic and foreign private businesses to invest in new technologies in the environmental field for the building of a green, clean and civilised Ho Chi Minh City.
In April 2017, at Nguyen Hue pedestrian street (District 1, Ho Chi Minh City), the city’s Department of Natural Resources and Environment and Bridgestone Vietnam installed 30 smart trash cans.
They are the first intelligent recycle bins to be installed in Vietnam and have been put into service at public places across the city. The intelligent trash can is capable of sorting garbage, filtering water, facilitating tree plantation and illuminating with reflective decals. The remaining 70 smart trash cans will be equipped in the downtown districts in the near future.
After making a working visit to the Go Cat WtE plant, Chairman of the Ho Chi Minh City People's Committee Nguyen Thanh Phong asked the city’s Department of Science and Technology to coordinate with the Department of Natural Resources and Environment and the related agencies to establish a scientific council to assess the effectiveness of the on-going experimental project.
On average, each day Ho Chi Minh City receives 1,500 tonnes of industrial waste, 300-600 tonnes of hazardous waste and 8,300 tonnes of domestic waste. The city strives to carry out a classification of its waste at source for 50% of the garbage, while reducing the rate of landfill to 60% by 2020 and to 25% by 2025, as well as introducing subsidised pricing policies for recycled products in order to encourage investors to change their waste treatment technologies.
Therefore, investors can make specific proposals and submit them to the city authorities for evaluation and consideration for the treatment of domestic waste to generate electricity, with a conversion capacity of 1,000 tonnes of waste per day to approximately 20MW of electricity, while ensuring not to generate environmental pollution and affect the quality of life for local residents.
This August, the city’s Department of Natural Resources and Environment and Department of Science and Technology will measure the quality of the air during the operation of the plant, as a basis to support its expansion. The Ho Chi Minh City government has also proposed a technical standardisation of specific types of waste; in addition to industrial waste, as it is necessary to extend treatment capacity to cover a wider variety of waste products.
Commenting on WtE, Assoc. Prof., Dr. Ho Long Phi, Director of the Centre of Water Management and Climate Change (Vietnam National University – Ho Chi Minh City), said that this model should be encouraged in the context of the environment in large cities such as Hanoi and Ho Chi Minh City that are polluted by waste.
With the increasing and overloading of garbage, it is a difficult task to treat waste with a proper process without causing environmental pollution. The solution to treat waste for renewable energy is a prerequisite in order to turn the city into a clean and civilised urban area. Therefore, there is a need for stronger policy support for investors to encourage them to invest further in the field of WtE.
According to Dr. Phi, for similar technologies and solutions to be expanded and developed in the near future, the cities’ authorities need to create favourable conditions regarding facilitated mechanisms, support for funding, land and taxes to make WtE a truly useful source in modern life.
Source: Nhandan online