Recently, Kathmandu Metropolitan City (KMC) published a public notice Encouraging people to separate biodegradable and non-degradable waste before handing it over to collectors. Several people support this idea believing that this will miraculously solve the waste disposal situation in Kathmandu. There is talk of making compost from biodegradable waste, recycling what can be reused and burning the rest. All these ideas sound suitable for waste management, but the million dollar question is whether these waste management ideas for Kathmandu are feasible and viable.
Waste segregation means we need more containers to store different types of waste and more trips to landfills to dispose of it, increasing management costs. Monitoring of sorted municipal waste is complex and not always pure, so biodegradable waste still needs to be separated from contaminants, which can be costly. Composting is a slow process and takes up a lot of space and time. Many composting facilities in Kathmandu have failed due to the lack of a compost market. Waste incineration is similar expensive and consumes a significant amount of energy. The heat from the incinerators can be sold to large industries such as cement factories, but it is necessary to lay a good network of pipes, which is expensive and cumbersome.
In addition to separating waste at home, KMC needs to consider alternative waste management practices that are appropriate for Kathmandu. Waste management experts have proposed a simple, well-known principle for sustainable waste management: reduce, recover and recycle. These principles will go a long way towards solving the problem of waste management in Kathmandu.
First, we need to understand the waste flow scenario to reduce waste production. Most of the food waste generated in KMC comes from raw or unprocessed food transported from outside the Kathmandu Valley. Encouraging the transportation of ready-to-cook or ready-to-eat food (e.g. peeled and sliced potatoes), vegetables, meat and other produce will prevent a significant amount of food waste from entering the city. For example, 15 percent of a potato becomes waste after it has been peeled and made ready to cook. Kathmandu consumes about 92,000 tons of potatoes per year, producing 14,000 tons of potato skins.
Similarly, Kathmandu consumes 34,000 tons of meat products per year, which means that 20,000 tons of animal waste are produced annually. This can be reduced by bringing processed meat from outside instead of live animals. Many other products come with potential waste, which can be reduced by bringing the processed product home. Transporting ready-to-cook meat instead of live animals reduces waste and eliminates waste product cheaper. The promotion of biowaste consumption at home through rooftop farming needs to be promoted more. It is also important to support window farming in Kathmandu as a significant number of people live in rented rooms or apartments that do not have access to the roof.
recovery and recycling
Nepal imports 985 tons of coal annually and spends 1 billion rupees on it 2020. But recycling our organic waste could help us replace coal with briquettes. There are several ways to make briquettes from MSW, but a simple method is to mechanically dewater organic waste mixed with a binder and press it into a mold and dry it. This briquette can be used by various industries such as brick and cement factories to generate energy. With this model, only a few companies can consume the entire briquette production. KMC produces approximately 73,000 tons of municipal waste or 40,000 tons of organic waste annually. Organic waste contains about 90 percent moisture, which must be pressed to dehydrate it, reducing 80 percent of its weight and 50 percent of its volume. Based on this calculation, 8,000 tons of briquettes can be produced annually from Kathmandu’s organic waste, offsetting Nepal’s coal needs and reducing imports.
Kathmandu produces 550 tons plastic trash yearly. Briquettes made from plastic waste have already been tested Nepal on a small scale. Plastic briquettes are an excellent solution to eliminate non-recyclable plastic, but cleaning up harmful fumes can be expensive. In addition, this requires multiple processes and thermal energy, which can be costly. A better solution would be to change the policy to produce recyclable plastic and recycle it into new plastic. However, if the stove or boiler can accommodate the burning of raw plastic, this can be beneficial as plastic has a high calorific value: 10,000 Kcal/kg.
Significant pollution pollution is caused by empty plastic bottles, which are often found on river banks. Around 400,000 Plastic bottles are thrown away in Kathmandu every day. Plastic bottle pollution can be controlled by the companies that use them, such as B. Mineral water and beverage manufacturers are responsible for the disposal of empty plastic bottles. Maybe they can pay for the empty bottles (say Rs 5 each) for the consumer to collect and sell instead of throwing them on the street. Manufacturing valuable/salable bottles by any company that uses plastic bottles is common practice to reduce plastic bottle pollution in many developed countries, inclusive Finland.
It is well known that there are many ways to recover value from different waste streams, but only a tiny fraction of it is recycled and a large fraction goes to landfill without recovering its value. Many factors must work together to address waste and one of the most important factors is the development of the concept of waste recycling business. A quick example of a functional waste business is household waste collection, as this is easy and profitable for the entrepreneur. Waste contractors receive a fee from households to collect and landfill their waste. Managing a larger amount of accumulated waste is complicated, expensive and requires significant efforts from local government. Public-private partnership is a very successful model for municipal waste management. For this model, the municipality needs excellent policies such as economic development, subsidies, low-interest loans, investment guarantees and market guarantees for its products (biogas, electricity, compost, animal feed, protein) to attract entrepreneurs. And of course it is necessary to work closely with other stakeholders.