ADDA hosted Neighborhoods of Tomorrow 2018, on 8th of September, which was a futuristic workshop to help management committee members to kick-start initiatives in their communities. One of the most important topics discussed was In-House Composting Options for Gated Communities. Savita Hiremath was the expert speaker and we could not have asked for a better person for this session. When she started exploring this in 2011, no methods were available. It took her 18 months to get one system implemented and failed 6 times with major problems. Now, she has a solution to any problems related to composting.
Savita Hiremath, Core Member of SWMRT Solid Waste Management Roundtable (SWMRT), an organization focusing on waste management in Bangalore. It has been instrumental in the formulation and implementation of decentralized waste management policies issued by the Karnataka High Court and civic authorities since 2009. She is also a Bangalore-based independent journalist with stints in Deccan Herald, The Times of India, The New Indian Express and Acharya Institute of Journalism (HoD) spread over 12 years.
Firstly, what is composting?
It is the biological process of breaking up of organic waste such as food & animal waste, manure, leaves, grass trimmings, paper, worms, coffee grounds, etc., into an extremely nutritious, humus-like substance by various microorganisms including bacteria, fungi and actinomycetes.
There is no requirement of special containers, what is crucial for the best result is just the right atmosphere. There are two types of composting – Aerobic and Anaerobic composting.
When aerobes work with the presence of oxygen or air, its called aerobic composting and it is recommended for large-scale composting. Whereas the composting that doesn’t require oxygen/air is the anaerobic one, which is recommended for individuals doing smaller scale composting. The kitchen waste is the easiest to compost and gives the best quality of compost in three weeks.
She also mentioned that most people are worried about odour when it comes to composting. It happens usually due to high or low moisture, and people just give up on composting. It can be easily rectified by adding dry leaves or coco peat-based inoculant. She also added that the composting process should be process-centric and not person-centric! Not one person should be responsible, the whole community should be responsible for the system and all the staff should be trained on the composting system, not just one or two. The composting also should not be power or water intensive. Another important aspect to be considered is that your composting system should not hurt someone else’s’ human rights. You should always consider your staff and security before finalising on a composting system.
She stressed on the importance of having a shredder for large-scale composting because it reduces the time taken for composting to more than half.
Everything starts with segregation. Composting can be even hazardous if segregation is not done properly. It does not take more than 7 days to get segregation right in your community. A fact most of the communities are segregating the waste nowadays. Ms Savita also added, “Once it is mixed, it cannot be fixed!”
Nowadays, there are so many wonderful products for composting starting with even zero cost solutions. The cost is independent of the quality of compost. You can start composting at the terrace, parking areas or even clusters of composts distributed in the society and you can try out different combinations of composting techniques from vendors.
A few composting systems are listed below along with their pros and cons.
A few composting systems are listed below along with their pros and cons
- Good for communities with large garden.
- Almost zero-cost solution to process all garden waste.
- Minimal effort
- Space required – 6×6 ft for one pile. (Not considering space for staff to do the work).
- The width has to be only 4 feet to ensure that the workers can reach the centre portion of the piles.
- Eco Digester – A Bio-Meth solution
- Suitable for medium-to-large communities, where biogas can be used up. (Canteens, Schools or similar establishments)
- Almost zero maintenance cost and money recovered in a few years.
- Space for a Digester that takes in 25 kgs (50 houses, approx) is around 5ftx5ft.
- Extra space on the terrace to place the biogas balloon.
- Needs a meshed enclosure to keep off rodents.
- If no natural wind movement, then the stirrer needs to be power-driven.
- Placing it closer to kitchen avoids heavy plumbing work.
- Suitable for small-to-medium sized communities (up to 100 houses).
- Rain-proof, Rodent-proof.
- Can fit in anywhere—terrace, basement (with good air circulation), out in the garden.
- They work in pair. One pair is enough for up to 20 houses. It is longlasting.
- Cannot handle very large quantities.
- Suitable for small-to-medium communities (up to 200-250 houses).
- Can be done in the basement if there’s a spot with very good air circulation.
- Low on Capital Expenditure. Composting done in milk crates.
- Space-intensive. Needs at least 12×12 ft for 200 houses.
- Needs a rain-proof, rodent-proof room.
- Sudh-Labh Aerobic Digester
- One digester is enough for up to 100 houses.
- Fits in corners. 6×6 ft enough for 100 homes.
- Needs a roof to prevent rainwater splashing.
6.Marigold Solar Compost
- Suitable for communities of all sizes.
- Aesthetically designed.
- Uses sunlight to process kitchen rejects.
- Fits in the open areas, on the terrace. Not in shaded areas/basements.
- Rain-proof, rodent-proof.
- Available in 3-4 capacities.
- Cannot handle very large quantities.
- Shudh-Labh Barrel Digester
- Good for small-to-medium communities.
- Low-cost solution
- Fits in almost anywhere. Good for parking, basement and open areas with a roof.
- Easily portable.
Cons – None
- Cement Tank
- Can handle large quantities (800-900 kgs of waste at once)
- Highly Capex
- Demands perfect masonry work.
- Not portable.
- Steel Bins
- Perfect for terraces
- The bins have enough holes let the air in & are mobile. The lid is easy to operate with handles on two ends. The bottom has a hole to let out leachate and is collected in a plastic tray.
- Temps go beyond 60-70 degree Celsius on hot days. Pathogens perish.
- Not Rainproof
- Zero cost Rainbow drive method
- Very low on capital and operating expense.
- Not labor-intensive.
- First a layer of dry leaves and then 8-10 inches of kitchen waste. Always topped off with dry leaves. A gunny cloth is wrapped around the steel mesh ring to contain moisture and prevent spilling.
- Needs space to store half-done compost for maturing.
- Unless kept clean, aesthetics can be a problem.
- Dry leaves are crucial.
- Orbin Solo
- Well-designed, compact and portable.
- One unit takes up 3ftx3ft of space.
- The total capacity is 80 kgs or 110 litres. One can add up to 1.5-2 kgs of fresh kitchen waste per day.
- Continuous composting.
- No leachate loss.
- No odour or rodent issues.
- Scalability limited to one point.
- Orbin Stax
- Vertical space management.
- Continuous flow system.
- The unique modular structure that allows stacking of extra waste collectors depending on the quantity of waste to be handled.
- Cocopeat-based inoculant.
- Good aeration.
- No smell or rodents.
- Good quality compost in three weeks.
Cons – None
- Leaf composter
- A good solution for composting dry leaves
- Simple structure, easily replicable and scalable.
- Continuous composting.
- Can add 20% of cooked rejects also.
- Easily portable.
- Low cost. Can be fabricated locally.
- Structural integrity can suffer due to continuous top-ups.
- Better go for very strong, high-gauge stainless steel to avoid rusting.
- Easily collapsible, portable aerobic composting structure.
- Made out of steel mesh.
- Available in 3 sizes for less than 20 homes to 70 homes.
- Works on coco peat-based inoculant.
- Harvesting process made easy with an opening in the front.
Cons – None
- Composting done using earthworms.
- Simple cement tanks with a mesh lid.
- The most nutrient-rich compost.
- Difficult to handle kitchen waste on a large-scale.
Ms Savita also spoke about composting systems that communities should not choose – the ones that offer automatic composting in 24 hours. They are just glorified incinerators. No machine can make compost in 24 or 48 or even 72 hours. It takes a minimum of 3 weeks. The output of these is not compost, but burnt carbon which can pollute air, water & soil. The temperature in these systems can go up to 100-degree Celsius. But there are several microbes in actions at lower temperatures that happens naturally and creates the best quality compost.
She concluded her session that odour, diseases by touching compost and difficulty to handle are just myths to be broken by our communities. She finally added it’s important not to dry the compost directly under the sun and excessive sieving is also not good for the compost.
Through her blog Endlessly Green—http://www.savitahiremath.com—which has 4,000 followers, Savita has created a go-to open source where she documents SWM-related issues. Her blog recently bagged the “Social Media for Empowerment Award-2018” conferred by Digital Empowerment Foundation, New Delhi. Through Facebook and WhatsApp, she interacts with hundreds of green champions from across India and helps them pick the right composting method for their community.
As an icing on the cake, Mr. Ramakanth, a renowned activist who is been fighting for a cleaner Bangalore for several years, shared a few simple things everyone can do for a cleaner city. N.S. Ramakanth left his job as a chief engineer with a German company and came back to Bengaluru in 1989 when his mother fell sick. On returning to his birthplace, he was appalled to see the polluted and filthy environment in the city. He decided not to take up another job but to devote his time to raising awareness about the poor waste management in the metropolis, chasing municipal corporation officials of the BBMP to clean up the filthy lakes in the city.
Reduce, Reuse, Recycle!
Mr. Ramakanth said that waste management is basically the 3Rs – Reduce Reuse and Recycle and reduction of waste is something everything can contribute on. Firstly by avoiding all one-time use items like tissues and disposable plates. Also banning mineral water bottles and storing cloth bags at security where people can use when required and return it later. Another innovative idea he shared was that each resident can contribute one set of crockery to create a community plate bank, and can be used for all the events in the community.
Lemon, which takes longer to compost can be cured along with jaggery for a month after decantation can be used as a natural cleaner and the top layer can water the plants as well. Mix 1 part of jaggery with 3 parts citrus peels and 10 parts water in a loosely-capped, airtight container. Store the mix in a cool, dark place, opening every few days to release the gas that builds up. In 90 days time, the first batch of bio-enzyme can be produced. Adding a few granules of baker’s yeast will speed up the process to two weeks. Separate the pulp from the liquid and use it to clean steel and ceramic surfaces, even as a floor cleaner. Similarly, coconut powder can be used for making natural shampoos.
Even at this age, he works every day, only uses public transport and even remembers to put his bus tickets in the composting system he has set up at his home. We need more people like Ms. Savita and Mr. Ramakanth to trigger communities to take up initiatives for a better sustainable city in the future,