THE rapid growth of environmental risks in Africa is becoming a global problem, which requires urgent efforts of the international community. The difficult financial and economic conditions faced by most African governments place special demands on the effectiveness of projects to combat pollution and climate change. Waste to Energy (WtE), a complex of technologies that have been successfully implemented in many developed countries, is the most relevant trend of the energy transition in African circumstances. One of the launching pads for their use in Africa is Tanzania, where the future of the national economy directly depends on the competent management of environmental risks.
In the coming decades Africa will maintain the highest rate of urbanization in the world. According to the UN, cities such as Cairo, Kinshasa and Lagos have already become metropolitan areas with a population of more than 10 million people, and Luanda, Johannesburg and Dar es Salaam are among the African cities that will join this list by 2030.
The rapid and poorly controlled city growth will long remain a constant source of problems related to providing their residents with clean water and electricity, waste management and rational use of land. Africa's demand for energy resources will grow at an explosive pace – according to the BP Energy Outlook 2019 forecast, the continent's electricity demand will almost triple by 2040.
But the current state of the energy and utility infrastructure in African capitals is mostly deplorable. The main source of energy is often dirty fossil fuels, access to clean water for many residents of large cities remains a luxury, and the collection and disposal of household waste is at a primitive level.
At the same time, Africa cannot remain aloof from the global energy transition process. Moreover, without a fundamental improvement in the environmental situation in Africa the efforts of other countries may be in vain – they will simply be undone by the uncontrolled climate risks of the black continent. The most pressing question, therefore, is which green energy initiatives can produce quick results in Africa.
An Adequate Solution
It is obvious that most African countries, for objective reasons, cannot afford, for example, extremely expensive projects such as the production of "green" hydrogen using renewable energy sources. Their implementation will require not only huge investments, but also advanced technologies and rare managerial competencies.
However, there is an alternative approach to solving environmental problems, involving the widest possible groups of the population in this process. This is the idea behind the WtE projects that are now being launched in African countries. To date, only one of them has been put into operation – a waste recycling facility opened in 2018 in the south-east of the Ethiopian capital, Addis Ababa. But there is every reason to expect that in the current decade WtE technologies will be extremely popular in Africa.
For Tanzania, their relevance is primarily due to the fact that a significant part of the country's income depends on international tourism. The country's huge nature reserves attract visitors from all over the world, but the anthropogenic load on the ecosystem may become critical in the coming years.
Natural scientists Kepha Nyampundu, William J. S. Mwegoha and Walter C. Millanzi in their recent article for BMC Public Health observe that Tanzania like other developing countries faces a serious concern and challenges on solid waste management, which is more pronounced in the commercial and market places where most people visit to sell or buy goods without necessary infrastructures and quality social services. The National Environment Statistics reported that 2,102 mln tones of wastes are generated in Tanzania mainland regions including Arusha, Songwe, Dodoma, Mwanza, Songea, and Rukwa. 1,197 mln tones (57%) of the total generated waste in those regions came from the households.
It is no coincidence that one of the first WtE projects in Tanzania will be implemented near the world-famous natural monument - Mount Kilimanjaro. Last year construction of a waste-to-energy plant began in the Moshi area near the Kilimanjaro National Park with the support of the German city of Tübingen. The cost of the project is approximately 800 thousand dollars – quite an adequate amount for such initiatives to become more and more frequent in Africa. In any case, the mayor of Moshi, Raymond Mboya, expects that this will not be the only modern waste recycling plant.
In most cases Tanzania and Africa on the whole need to discover and try change waste to useful energy which will help in the growth of economies but reduce the environment damages, says Machibya Matulanya, energy and minerals analyst from Geologist Tanzania Atomic Energy Commission, former president of DARUSO. Currently Tanzania is prepared to deal with pollution including radiation in the potential area of uranium mining so as to reduce effects and environmental risks, he adds.
Waste to Revenue
The conversion of waste into energy is not discussed as often as projects related to wind, solar, water, geothermal or tidal energy. Nevertheless, WtE technologies have already proven themselves in a number of countries, for example, in the European Union, and their development has long been pursued by some of the largest energy companies in the world.
One of the most ambitious players in the global WtE market is the Russian State Corporation Rosatom. Over the past few years it has seriously diversified its project portfolio, adding to the nuclear power industry a variety of solutions in the field of non-traditional energy sources, including WtE.
The development and implementation of WtE technologies is carried out by the Atomenergomash machine-building holding, which is part of Rosatom. Since 1996 they have successfully implemented WtE projects in Germany, Switzerland, Great Britain and Russia. In December 2017 the contracts for power island equipment delivery were signed by PJSC “ZiOPodolsk” (JSC “Atomenergomash company”) with Russian customer for 4 WtE projects in Moscow area with waste capacity 700’000 tons per year and 1 project in Kazan city of 550’000 tons per year.
All the projects have been developed on the base of proven grate combustion technology, which is the best proven most advanced thermal waste treatment technology with regard to environmental friendliness, operating reliability, flexibility and cost-effectiveness. From the feed hopper and chute the ram feeder doses the waste onto the grate in a controlled way. The grate is composed of individual grate modules with alternating fixed and moving grate block rows. The hydraulically driven moving grate blocks stoke the waste and convey it through the combustion chamber as needed to achieve optimum burn-out. The airflow can be adjusted precisely to combustion requirements in every grate zone.
The contribution of Russian experts can help Tanzania to solve the problems that have already arisen when trying to implement WtE initiatives in the country, such as the project launched in Dar es Salaam. It is based on the country's approved Solid Waste Management System (SWM), which includes four stages - waste generation, collection, processing and reuse.
However, in real practice the interaction between different participants of the program turned out to be far from effective. At the local level the authorities do not consider WtE among their priorities, and this entails low budget allocations, weak implementation of bylaws and a decrease in the quality of management. But the Government of Tanzania remains confident that energy solutions under the SWM system will help address the problem of waste mismanagement and provide the country with a sustainable alternative to its current energy dependence on coal and wood.
The last but not least, Tanzania, rich in uranium, expects to have its’ own nuclear plant in the long-term. Nuclear power is cheap compared to other sources of energy, it is also sustainable and reliable source of electricity, and this is why rich and wealthy nations in the world prefer to explore on the nuclear power for electricity, Machibya Matulanya says. To his mind, industrial revolution needs sustainable power, without nuclear energy one can delay, like other economies grow, Tanzania as a national will achieve and revamp much in the industrial sector through use of nuclear energy. “So steps and plans taken in exploration of uranium will pave way to quick development and growth of economy”, analyst insists.