Ruminations, Musings, Expressions

“I’m willing to admit that I may not always be right, but I’m never wrong” — Samuel Goldwyn

Tag: Waste to Energy

‘Process — Do Not Recycle’

Note: For some mysterious reason known to the gods of cyberspace, my pieces on processing of plastic waste vanished from here. I am combining both pieces and re-writing this from my notes.

When processes are dealt with in a holistic fashion, they have a visible and positive environmental and economic impact.

Quoting from an earlier piece:
We have a tendency to view things in isolation, whereas everything in the universe is inter-connected. What is considered as ‘waste’ is the starting point for something that is useful, and so on, till we arrive at a state of zero-waste. Nature does not waste anything, only man does.

So a solution is produced for one ‘problem’, without taking into account interconnections with that ‘problem’, and in the end we have produced more problems than solutions.

Dealing with plastic waste is a world-wide problem and has solutions. Banning plastics is not a solution. Dealing with plastic waste as a resource is. There is a lot of it already accumulated, and more being generated every day. Taking a somewhat contrarian view I am proposing that till alternatives are developed for using plastic packaging and products, plastic waste be used as a valuable resource, which is why this piece is titled, ‘Process — Do Not Recycle’.

Recycling creates it own set of problems, as parts of the unused waste then either clog up drains and waterways, or is dumped in landfills.

Processing on the other hand, (properly done), converts the plastic waste to usable products, leaving no waste for a landfill or polluting the environment. ‘Properly done’ is the keyword here. Like all processes, proper protocols have to be followed, for the desired results. It will be noticed that wherever problems have arisen, it is due to cutting corners, whether in the process of collection or in processing.

The Potential

Let us see what is possible when plastic waste is processed. This includes all kinds of plastic wastes including synthetic fabrics.

One tonne of plastic waste has the potential to:

  • generate 1 MW of electricity from waste heat generated during the process of conversion;
  • generate around 900 litres of fuels, the final products — diesel, aviation turbine fuel, kerosene, fuel oil — determined by the processes used, which are currently available;
  • generate cooling, air conditioning, or heat, depending on the location.

The properly done processing means the plastic waste is converted in a sealed building, where the air from the inside of the facility is fed through a scrubber, before it is released into the atmosphere. This is not a process for cutting corners, where accountancy procedures are allowed to override technological and safety considerations.

The positives

  • Employment generation, direct and indirect, starting from the collection process, processing, and distribution (of fuels).
  • No plastic waste in the streets, drains, waterways, which means cleaner rivers and oceans, and no plastic waste going to landfills.
  • Creation of value in terms of electricity generation, and fuels.
  • Cleaner environment.

To those countries engaged in a debate on exporting their plastic waste, I’d say don’t. Process it, don’t throw away a valuable resource by exporting it.

I have not touched on household and commercial organic waste, which can be used to generate Methane (to electricity), Manure, and Water. Again zero waste goes to a landfill.

Similarly I haven’t touched on cotton products and textiles, which can be processed for bio-ethanol.

The proposition is, that it is possible to have a zero-waste situation if the waste problem is tackled in a holistic manner.

Kitchen “Waste”, Surplus Power, and No Pollution

Waste Resources and Pollution are intrinsically connected. Tackle one and it immediately has a positive effect on the other. One cannot tackle parts of an ecosystem in isolation and hope for results. One has to deal with all parts of a system — all the gears in a watch have to mesh together perfectly if one wants perfect time. Have tried to suggest solutions using currently available technologies and processes. Better solutions may be available. As always my suggestion to readers is to offer solutions, rather than try and pick holes.

Don’t find fault, find a remedy; Anybody can complain. — Henry Ford

Several things have happened simultaneously in the last week of November–first week of December 2015: floods in Chennai, COP21, (also known as the 2015 Paris Climate Conference), and the Arvind Kejriwal government trying to press into effect pollution control measures on an emergency basis.

Government functionaries have been quick to blame climate change for the floods in Chennai, forgetting  that it is their policies, (or absence of them), which were directly responsible for the floods. Swati Thiyagarajan of NDTV, has written an excellent article titled The Stupid Decisions That Left Chennai So Vulnerable, illustrating that the Chennai floods were a total man-made disaster, as are a lot of environmental disasters in India.

World leaders seem to have reached some kind of an agreement in Paris, though no one is sure whether they have reached any kind of agreement, or not. The results which will follow from their deliberations remain to be seen.

In Delhi, the Kejriwal government is trying to tackle problems which have built up over the years due to the implementation of faulty policies, influenced by the pressure of various lobbies and vote-bank considerations, whose consequences were either not foreseen, or brushed under the carpet.

The problems of Delhi cover a very wide canvas, which we’re sure the Kejriwal government will find solutions to, since they are about the only elected government which seems to have some kind of vision and plan regarding what has to be done.

However since this piece is supposed to be about about utilising waste resources and controlling pollution, we shall focus on those. (I am not laying out a detailed blueprint here, but pointing out what can be done and the benefits).

Using “Waste”: Energy Potential of Organic/Animal Kitchen “Waste”

Disposal of waste is not a problem confined to Delhi, but to the country, and most parts of the world. The only way to tackle it is, to follow a basic postulate: nothing should go to any “landfill”, in fact the word “landfill” should not exist in the lexicon of any municipality or local authority. The corollary to the postulate is “localised processing”.

Let us start from a basic unit, the place of dwelling, which could be a single room in a slum, or a huge bungalow, classified as a household in the Census.

All of them generate by-products of everyday living. We shall focus on the kitchen, and leave recycling of water and sewage to another time. Kitchen waste is something which is common to villages, towns, cities (whether dumb or smart, old or new), rich or poor.

The Kejriwal government is already doing good things on the sewage and water recycling front. (I keep referring to the Delhi Government as the Kejriwal government, to make it clear that I am referring to the elected government).

Saw this in my Inbox a few days ago, a home biogas unit. The empty weight is 35 kilos, and the dimensions are: 127H × 165L × 100W cm. [Update: There are several Indian manufacturers of operationally similar units].

Home-Biogas-0

Sourced from http://www.homebiogas.com/

Here is the video link. According to the specifications on their site each unit produces 600 litres of gas (approx. 65% CH4, 35% CO2) per day, with an input of up to 6 litres of food waste or up to 15 litres of animal manure (dairy farms, urban–rural areas). The gas can be used to run a micro-turbine, but it can be used more efficiently when it is burned to generate steam, which in turn can be used to generate electricity with a low pressure module like the EM-150 (from EAWC), rated at 150 kW at a steam pressure of 5 bars. One could also use Enertime’s Organic Rankine Cycle machines, which can convert heat sources (between 90°C and 300°C) directly into power with a 75% efficiency in cogeneration. (These are examples. Other combinations can be used).

The point that is being made, is that no organic resource should be transported to a landfill, but used at its point of origin. (This eliminates a big cause of environmental pollution)

According to the census figures for 2011, there were 3,340,000 households in Delhi. Let us say they have increased to 3,350,000 in 2015. Assuming 8 biogas units (households) are required to feed one 150 kW module for 24 hours, we get a potential figure of  62,812 MW. (On 16 July, 2014, according to the Economic Times, the peak demand was 5,925 MW). We have still not taken into account organic/animal waste from restaurants, hotels, malls, shopping areas, wholesale and retail vegetable and fruit markets, fruit juice stalls, roadside food vendors, the slaughter house, and the like. Let us average out this figure and assume that 35,000 MW is generated using organic/inorganic waste from all sources. This makes Delhi surplus in power. (Generation of electricity from sewage has not been added to the equation).

The individual price of the biogas unit is US$ 1500. The price can be brought down once they are made in large quantities here. The same goes for the steam modules. This whole combination also meets a very important parameter, which critics of renewable energy have, 24×7 operation, and which all of us, who are supporters of renewable energy strive for. This generation model can work as a series of linked micro-grids. (I am not suggesting any business, technical, or billing model at this point. This will have to be worked out by entrepreneurs, and it would be better if no large corporate is involved in the exercise).

Consider a gated cluster of 75 flats. They have a potential capacity of 1350 kW. Let’s say 945 kW at 70% efficiency. Their peak requirement would be 600 kW at a sanctioned load of 7.5 kW (5 is the norm) which includes external lighting and power for the cluster’s water pump. They would have a surplus of approximately 350 kW to feed to an external grid. In short, each gated cluster can be made self-sufficient in electricity with zero-generation of waste.

Advantages of the biogas-steam generation model
  • Can operate on a 24×7 basis.
    (Not weather dependent, no battery storage required)
  • Will never run out of feedstock, unless people stop eating.
    (Recycled water can be used for the steam unit).
  • Ideal for an urban environment, footprint of the unit is very small (127H × 165L × 100W cm) plus a slightly bigger area for the generation unit.
  • The only waste which would need to be collected from any residential or commercial area is plastic, paper, glass, and a minuscule amount of metal. All recyclable materials.
    Plastic waste can be converted to biodiesel. [Update: Around 2,51,850 tonnes of plastic waste are generated per year in Delhi. If all of it is converted to diesel, then you get 151,110,000 litres of biodiesel per annum, and 50,370 tonnes of petcoke. Petcoke can be further gasified, and the gas used for generating on-demand electricity.]
    Efficient collection of plastic waste would also save drains from being clogged. (Banning plastic bags is not a solution till alternatives are available. Over 25,00,000 litres of milk in plastic poly-packs is supplied every day in Delhi. The disposed poly-packs are a valuable resource. Add to that disposable plastic bottles, glasses, plates, et cetera.)
    Collection would be done at source rather than have waste collectors sort through “trash” dumped on roadsides. Since there would be no trash on the roadsides, cows  and other animals would not feed on trash, and get choked with plastic. It would also cut down on flies and other insects attracted to trash
    .
    An efficient collection system coupled with fines for littering, would see the “trash” being utilised, and the streets and market places remaining clean. Which in turn would mean there would be nothing to attract flies.
    Delhi then can then have roads and streets to rival Singapore’s.
  • No land would be required for landfills, which would mean land earmarked for landfills, can be freed up for development of schools, hospitals, sports complexes, no malls.
    • No landfill therefore no pollution of air, and no leaching of toxic material into the ground, therefore no pollution of ground water.
    • No landfills mean drastic reduction of trucks required for collection and transportation of waste for long distances, which consequently means reduction of running and maintenance costs.
  • The main benefit is a cleaner city, and consequently a cleaner and an environment free of pollution.

The success of this system will depend on the efficient collection of the waste resources from individual households, which can be organized. A system of collection is already in place in Delhi and most cities. It would just need refining. [Update: This is what a waste collector has to say, though I’d rather call them Resource Collectors].

Source: The Hindu, Bengaluru, 11 December, 2015

Source: The Hindu, Bengaluru, 11 December, 2015

The costs of this kind of a system will be cheaper than any other renewable source generation system in use presently. Before doing any calculations it would worth considering healthcare costs, which would also be cut down, (remember complete ecosystems, nothing in isolation).

Killer Air-1

Source: www.vogmask.in

Trees and Prevention of Air Pollution

A by-product of the biogas unit is liquid fertilizer, which can be used for fertilizing trees, vegetation, and gardens. It is an environmental tragedy that the first thing which is common to any new project, roads or buildings, is the cutting down of trees. The authorities then announce that they will plant 1o times the amount cut down, but 10 to 20 kilometres away. It’s like cutting out someone’s lungs, and placing them several houses away and then asking that person to breathe. A 50-year old tree cannot be replaced by saplings planted elsewhere.
Why cut down 50-year old trees to widen highways. Let the additional lanes come up on the other side of the trees. In fact one can separate car and truck traffic this way.

This has been a major contributory cause of air and heat pollution. It is surprising that no one has thought of using transplantation rigs, which can transplant trees up to 15 metres in height. A certain degree of mortality is expected, but the majority of trees can be saved.

tree-planting machine5

Source: http://www.landscapeonline.com/

A tree transplantation operation by one such machine can be seen in this video clip.

The removal of trees and vegetation, cuts down on the capacity of the absorption of carbon dioxide in the areas where they are cut, and raises ambient temperatures. No trees and vegetation also add to the build up of dust. (The Delhi government is arranging for vacuum cleaning machines to suck up dust on the roads by April 2016).

interlocking-pavers-grass-paver-500x500

Source: Paving Stone (India) Pvt. Ltd.

Porous Pavement Tiles
This is another measure which has also been announced. Pavement tiles which allow grass to grow through. This will allow rain water to percolate to the ground below, prevent flooding, trap dust, and cut down on heat generated from purely concrete tiles. (Liquid fertilizer would be available in adequate quantities from biogas generation for the grass and trees).

Water Bodies
The flooding in Chennai was caused by building over catchment and drainage areas. This has happened in Delhi and the NCR also. Water bodies are a part of a healthy environmental system and need to be revived and kept alive.

Air Pollution: Vehicular
Source: thehindu.com

Source: thehindu.com

This is the immediate issue of the moment. As I mentioned at the start, the Kejriwal government is trying to tackle a problem which has built up over the years.

We can take the MPD-2021 as the main culprit, which allowed the construction of an extra floor in Delhi. Delhi does not need to go vertical, (not in a seismic zone). The development of satellite towns like Gurgaon and NOIDA were supposed to relieve population pressure in Delhi. This was nullified in one stroke.
(A thought, since all towns around Delhi want be part of the NCR, why not make the NCR a State ?)

Builder’s flats started coming up, and the illegal ones became legal. So instead of one household per plot, Delhi suddenly started having two to six households located in the same physical area, without any scaling up of the electrical, water, or sewage facilities. This placed enormous pressure on civic facilities. Another effect of this development was that cars, which were hitherto parked inside houses, were now parked on roads, and instead of one car there were four or five now — two to six households in the same space as one. So all internal roads immediately became congested, and parking started becoming a law and order problem.

The effects of this over-population spilled over to external connecting roads. Bad road engineering, coupled with indisciplined driving habits, have exacerbated the problem. Congested arterial roads exist in all areas of Delhi. Flyovers haven’t helped. They move traffic in one direction or are supposed to, but cross-traffic is held up, and idling vehicles add to air pollution, as well as wastage of fuel. We now have traffic jams on flyovers, and it wouldn’t surprise me if some of them collapse one day. They were designed for dynamic loads and not static loads.

Road engineering is one area the Kejriwal government is already working on. They seem to have worked out solutions, since they have identified the problems, so hopefully traffic will move more smoothly once changes are implemented.

Arvind Kejriwal was speaking about dedicated elevated bus corridors, a few days ago. My suggestion is that if Delhi decides to go in for the electricity generation model suggested above, the buses on those corridors should be electrically powered, which should cut down on air pollution.

Low floor buses add to traffic congestion. This is again peculiar to Delhi. They occupy too much of road space, and their drivers are not exactly like the BEST drivers in Mumbai, who stick to the left of the roads. Buses in other metros also stick to their lanes. These buses are totally unsuitable for plying on the internal roads in residential colonies, which were never designed for such huge vehicles. Have smaller sized low floor buses than the current ones to increase available road space, and make traffic movement smoother.

Traffic jam at the ISBT Anand Vihar Bus terminal in East Delhi. The DTC fleet has only 4,712 buses to carry 3.5 million passengers across the city, a number likely to go up if the government implements car rationing in Delhi. (Sonu Mehta/HT File Photo)

Traffic jam at the ISBT Anand Vihar Bus terminal in East Delhi. The DTC fleet has only 4,712 buses to carry 3.5 million passengers across the city, a number likely to go up if the government implements car rationing in Delhi. (Sonu Mehta/HT File Photo)

This is a scene repeated across most of Delhi; buses occupying multiple lanes, rather than a single lane, as they are supposed to. Bus schedules need reworking to avoid “bunching” for smooth flow of bus traffic. This would help commuters and  avoid traffic congestion at the same time.

Traffic regulation is under the domain of the police, and according to reports, the traffic police in Delhi is badly under-staffed. (I am not commenting on the governance problems of Delhi, which is not the focus of this piece. However as a citizen, I feel that control of land and the police should be with the Kejriwal government, to tackle the problems of congestion and traffic regulation, both of which affect air pollution directly).

The other vehicular factors which add to congestion and hence pollution, is indisciplined driving by two-wheelers, three-wheelers (passengers and goods), gramin seva vehicles, and over the last couple of years what are called e-rickshaws. This area can only be streamlined by the traffic police. As can be seen from the excerpt below, two-wheelers and trucks are the biggest cause of vehicular pollution in Delhi. It would therefore make more sense to get them off the roads than cars, to control vehicular pollution.

As per the draft report, [study by the Indian Institute of Technology, Kanpur], vehicular pollution accounts for 30 to 40 per cent of all air pollution, and of that around 34 per cent can be attributed to two-wheelers, 10 per cent to cars and 46 per cent to trucks. (Source: The Hindu, 8 December 2015)

Another cause of vehicular congestion is the allowing of weekly markets to be held on both sides of roads, leading to an increase in air pollution again. Let them be held in a large ground, so that sellers can still sell their wares, and not cause traffic congestion.

Governments have tried to get people away from using personal vehicles, particularly cars (a favourite target for environmentalists), to using public transport. Many more knowledgeable and well-informed people have already commented on this. The only way that this is going to be possible is to have buses and metro coaches with ‘seating only’ arrangements. Their users can pay more. However what must not be lost sight of is, ultimately it is public transport, and should not be treated on a commercial basis. (On a personal note, have had my pocket picked twice on the Metro, and even as a senior citizen, getting a seat is akin to winning a lottery).

The odd-even number regulation of vehicles would be effective for controlling vehicular pollution, if it targets the biggest polluters, two-wheelers and trucks. Targeting cars will not help. However, while the percentage contribution to air pollution by vehicles is smaller as compared to other sources of air pollution, it does require streamlining to reduce air pollution.

Air pollution from other sources, which can be seen below, have not been referred to. They require their own solutions along with controlling road traffic, if measures to control overall air pollution are to have any impact. Pollution from Gen sets can be cut down with the availability of 24×7 electricity, as well as consumption of diesel used by them.

Source: www.business-standard.com

Source: www.business-standard.com

 

Adoption of all the steps outlined above, should make Delhi more than self-sufficient in electricity, cut down pollution from various sources drastically, and make it truly a clean, green, city. This is a Delhi-centric piece but the solutions suggested can be applied to any metro city, and can be scaled down for smaller places.

[Reviewing this article, felt it would be incomplete without this element]

Urban Farming

Growing green roofs is now mandatory for new buildings being built in Canada and France. Middle Eastern countries facing dire food and water insecurity know that farming close to home can cut down greenhouse emissions and if farmed hydroponically can drastically cut the water bill — in some cases by 90%! Putting its money where American mouths is this company from Brooklyn called Gotham Greens which has just built the world’s largest rooftop farm — in Chicago.

To make this whole concept more integrated we add Urban Farming to the picture. This takes us to pre-kitchen waste stage. We already have liquid fertilizer and electricity available. Rooftops, barren or empty plots can be fully utilized. This will have the effect of:

  • Cutting pollution by cutting down on transportation of produce from farm to customer.
  • Creating employment for women and youth. (See image from Harlem Green below)
  • Offering fresh produce at stable prices and supplies without seasonal variations.
  • Cutting down on greenhouse emissions, and a host of other benefits.
Urban Farm of Harlem Grown (http://www.harlemgrown.org/)

Urban Farm of Harlem Grown (http://www.harlemgrown.org/)

In the middle of Harlem on a derelict plot of land where old men used to play cards, with no kids allowed, is growing one of the most exciting social projects seen this year. Harlem kids that were eating Twix bars for lunch are now eating fresh greens — food that they and their mothers are growing through a non-profit project called Harlem Grown. See more.
Latonya Assanah from Harlem, New York (pictured above) has an 8-year-old daughter who just “wouldn’t eat green things.” Today Assanah is the greenhouse manager, working days at the high-tech farm, which feeds 150 local Harlem families. It is part of the Harlem Grown non-profit farm. The farm stands on what was 4 brownstone houses in the middle of the city.

 

These images are from an urban farm run by Eden Works.

Edenworks-1Edenworks-2

There are already people involved in growing vegetables in what are called kitchen gardens. They would form a ready base for this kind of farming, and would also be able to train others. (Urban planners do need to shift their focus away from building shopping malls and constructing buildings on every available plot of land, and giving infrastructural, and economically and socially beneficial projects such as these, priority).

 

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