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warrior
07/02/2020 at 23:17
1

Hi malevil
There is a better source for that article at:
https://www.pnas.org/content/114/4/612
From there it is possible to download a full resolution PDF, with no need to register.

warrior
05/02/2020 at 23:04
3

As for the issue of “burning fuel to make fuel”, as mentioned by @craigglewis – one way to reduce the resulting atmospheric carbon would be to power the pyrolysis by using concentrated solar thermal energy.  It could be another application for the GoSol / Lytefire system.

A simple batch pyrolyser could be filled with waste plastic in the morning, and a day of concentrated sunshine would produce a single batch of liquid fuel.

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warrior
05/02/2020 at 22:52
1

I think that is an excellent point @s2019 – there are lots of places where poor people will just burn whatever combusts, locally, in order to cook.  They might have no real option of incinerating plastics at a high enough temperature to destroy toxic byproducts – so an option to obtain a relatively clean-burning liquid fuel, for cooking, would be of great benefit.

Unfortunately, if it was run as a normal business – then the people would probably still be unable to afford the resulting fuel.  They would resort to burning plastic again, which they could collect for free.

However, if a village-scale pyrolysis plant was run as a cooperative – allowing people to “earn” liquid fuel in return for collecting waste plastic – then that might be a viable operation.

warrior
02/02/2020 at 16:18
1

Is recycling broken?

Audio podcast (24 mins)

https://www.bbc.co.uk/programmes/w3csyth9

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warrior
21/01/2020 at 21:53
1

Hi @s2019 – good question.
This story suggest not a lot is being recycled.
There are not nearly enough recycling facilities to process their own domestic plastic waste – so it seems the extra imported waste is mostly being burned or dumped.

This item in Wikipedia tells a similar tale:

The report warned that there were regulation violations in the disposal of imported plastic waste to the country (plastic is burned on roadsides in the open-air, dumped in unregulated or poorly regulated dump sites close to bodies of water, discarded in abandoned buildings or just left to degrade and rot in the open) thus contributing to environmental pollution and harmful health impact for Malaysians.

warrior
20/01/2020 at 23:58
1

Malaysia returns 42 containers of ‘illegal’ plastic waste to UK

https://www.bbc.co.uk/news/uk-51176312

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warrior
03/01/2020 at 19:50
1

The plastic polluters won 2019 – and we’re running out of time to stop them

https://www.theguardian.com/environment/2020/jan/02/year-plastic-pollution-clean-beaches-seas

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warrior
27/12/2019 at 16:23
1

Revealed: microplastic pollution is raining down on city dwellers

https://www.theguardian.com/environment/2019/dec/27/revealed-microplastic-pollution-is-raining-down-on-city-dwellers

warrior
19/12/2019 at 02:37
3

Countries are trying to ban plastic drinking straws. The last thing anyone needs is a new source of plastic straws entering the environment.

https://www.nationalgeographic.co.uk/environment-and-conservation/2018/07/brief-history-how-plastic-straws-took-over-world

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warrior
02/12/2019 at 23:59
1

Yeah – I don’t think he’s doing himself any favours by talking about perpetual motion.

If his contention is that it takes 1000 kJ of fossil fuel burn to create 800 kJ worth of pyrolysed-plastic kerosine, then that would be a decent objection. That would not only be negative in energy terms – but when the 800 Kj of kerosine is eventually burnt, the total atmospheric carbon for that energy would be the equivalent of burning 1800 kJ worth of fossil fuel.

In fact, even if you got your 800 kJ worth of pyrolysed plastic kerosine by burning only 20 kJ worth of fossil fuel, you would still eventually send 1000 kJ worth of CO2 into the atmosphere.  But, either way, he doesn’t actually offer any numbers to back up his argument.

If this is supposed to be an argument in favour of EFW (energy from waste) plants – where the entire calorific value of the plastic is used to get electricity and heat – then why doesn’t he say so?  EFW also “disposes” of the waste plastic – and displaces an equivalent amount of fossil fuel use in power stations.  Of course it isn’t carbon neutral – as the plastic is fossil-derived in the first place.  So I guess it all depends on whether you want to instantly stop all energy from fossil-to-CO2 processes, or you are willing to accept EFW as a step in the right direction (like a heroin addict going onto a prescribed methadone programme).

Maybe he is advocating the “capture all the waste plastic and securely bury it” approach. This at least keeps the waste plastic out of the wider environment, I guess.

warrior
15/11/2019 at 23:00
1

Endangered red squirrel dies trapped in plastic jar
https://www.bbc.co.uk/news/uk-scotland-44977743

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warrior
15/11/2019 at 22:54
1

Stag died after being tangled in plastic tape on Jura

https://www.bbc.co.uk/news/uk-scotland-50432013

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warrior
01/11/2019 at 13:50
1

Argentina could become ‘sacrificial country’ for plastic waste, say activists

Argentina has changed its definition of waste in a move that could allow it to import millions of tonnes of plastic waste discarded in the US.

The country’s president, Mauricio Macri, signed a decree in August reclassifying some materials destined for recycling as commodities instead of waste, allowing looser oversight of mixed and contaminated plastic scraps that are difficult to process, and are often dumped or incinerated.

https://www.theguardian.com/environment/2019/nov/01/argentina-plastic-waste-dumping-ground-imports

In reply to: V4 Fume Extraction

warrior
30/08/2019 at 23:57
0

atapene – some kind of wet air scrubbing system should work, as Dirk mentions. But I’d start by using a weak solution of sodium bicabonate in water.  It should react with the acetic acid – and convert it to Sodium Acetate. This is non toxic, and shouldn’t cause any problems with disposal.

warrior
17/08/2019 at 20:24
2

Interesting paper posted on ResearchGate.

Pre treatment of Duckweed Biomass, Obtained from Wastewater Treatment Ponds, for Biogas Production

BTW, I thoroughly recommend having an account on ResearchGate.  Researchers regularly post copies of their own papers – so people can read them without having to go through university library accounts. That means that private researchers, who don’t have “institutional access”, are not excluded from obtaining the information they need.

warrior
10/08/2019 at 05:52
0

That is utter madness.
They are just making huge quantities of PVC swarf.

warrior
07/08/2019 at 13:25
0

Hi Alicia,

Have you been in touch with any of the Repair Café people?  Clothing & other fabric-based items are often included in the type of things that the cafes will repair.  Some of the regular local volunteers could already have the right skills, experience, and interest to help with your project.

There is a list of Repair Cafes here – and half a dozen seem to be based in and around Eindhoven.

In reply to: V4 Fume Extraction

warrior
05/08/2019 at 13:31
2

@s2019
I think that is a good point Stan.

Near where I live there is a plastics factory that makes bathroom equipment (baths & shower trays) from glass reinforced polyester resin.  Sometimes it is possible to smell fumes from the resin in nearby residential streets – but the fumes are presumably within limits, and I’ve not heard of any problems.

Without an objective outside measurement of toxicity, it is difficult to know how much of the various volatile compounds really need to be filtered out.  It is impossible to go by aroma – as different people have different abilities to smell dilute chemicals. (e.g. I’m like a bloodhound, and smell everything. My partner has never once detected an odour from the plastics factory.)

In reply to: Off Grid DC Power

warrior
28/07/2019 at 01:10
2

From https://livingenergyfarm.org/wp-content/uploads/2019/03/LELCS6.pdf

Living Energy Farm (LEF) has developed two unique electrical technologies. The first is “daylight drive” whereby we power high-voltage DC motors during daylight hours. Early generations of off-grid energy systems used low-voltage DC electricity from PV panels. Increasingly, PV panels are tied together in strings that produce much higher voltages. At LEF, 90% of energy use is based on daylight drive application of high-voltage DC power from PV panels. This dramatically reduces the cost of providing basic services like pumping water, grinding grain, cutting wood, or accomplishing any of a myriad tasks that are needed in a village. Combined with thermal storage, daylight drive is a much cheaper, more durable method of suppling stationary power than AC power systems.

The second technology we have developed at LEF is the integration of nickel-iron (NiFe) batteries with LED lighting and charging systems. We are pursuing the deployment of this latter technology because it can be easily deployed to provide lighting and charging services for people all over the world who cannot afford grid power.

How is that LEF found these simple, cost-effective ways of using solar electricity while so many well-funded engineering organizations did not? Because we have been looking for answers that are simple, cheap, and durable, and they are looking for energy systems that mimic the AC grid power available to middle class consumers in industrial societies. The answer you get depends on the question you ask.

NiFe batteries are heavy and expensive. They were in significant use in industry 50 – 100 years ago. They faded out because the battery companies could not make enough money on them. But that predated both the arrival of both easily available photovoltaic (PV) solar electricity and LED light bulbs. (Incidentally, the old industrial NiFe batteries had high standby loss, modern ones do not. The price of NiFes is also coming down dramatically.) With the demise of NiFe batteries, the nascent off-grid movement of the 1970s and 1980s standardized around the use of short-lived lead-acid batteries. Off-grid technologies have been crippled by poor batteries.

warrior
27/07/2019 at 21:58
0

Thanks @ratnag – it all seems more sensible now 😉

From your picture it also looks like quite a lot of your polymers are clear (so no fillers) which will improve your options when finding uses (or customers) for the waste.

Also – having a relatively large source of various good quality uncontaminated/decontaminated engineering plastics offers even more interesting possibilities.  Usually items made out of the more exotic grades of polymer are not available in numbers that make any form of recycling cost effective.  But the higher price of the engineering plastics, compared to the general commodity types, might mean that someone will be willing to pay for your collection.

But as you say, identifying some of these plastics could be a challenge.  The manufactureres are not going to bother fully labelling them, as they don’t expect them to be recycled.  And they also might not want to give away any manufacturing trade secrets, so may not tell you the full details even if you asked.

warrior
27/07/2019 at 16:27
0

Hi @ratnag

10 out of 10 for wanting to do something worthy and ethical with the byproducts of your healthcare 😉

However, you might have more of a problem than you anticipate – for a couple of reasons.

For a start, I’m quite amazed that the waste plastics you have can be simply placed in your domestic trash.  In some countries that would be an offence – as a lot of it would be classed as “infectious waste” and would need to be sent to an authorised treatment site (possibly for incineration). Just leaving waste disposal up to the recipient of the care products seems a little bizarre.

This page at the World Health Organisation website has a handy summary of some of the issues.

This also means that anything you decide to make with the “blood contaminated” plastic could end up being classed as infectious, unless you can find a way to treat it to the satisfaction of the authorities.  Washing methods (as being investigated by the PP team in the Netherlands) probably wouldn’t be seen as good enough – and full steam autoclaving might be too expensive for a home-based project.

The second issue, as you’ve already discovered, is the range of plastics that you’ve been left with.  Many of them are classed as Engineering Plastics. As such, they fall outside of the rather simplistic “1 – 6 recycling code” system used for Commodity Plastics – and are essentially code 7 or “other”.

However, I’m guessing that most of these will be the most heavily contaminated plastics – such as the polysulfone membrane tubing – which might be beyond economical treatment anyway.  Unfortunately, you might find that the HDPE fluid container is the only easily (and safely) recyclable item.

warrior
27/07/2019 at 10:18
1

I like the idea of hunting and skinning a sofa… 😉

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In reply to: Ocean plastic research

warrior
26/07/2019 at 22:53
0

Hi a-mind-of-comfort

has anyone looked into adding an exhaust setup to their machines?

See this topic.

Who does anyone know the proper amount of air exchanges needed to handle such fumes?

See this document.

warrior
20/07/2019 at 22:58
1

Story in this weekend’s Observer newspaper:
How melting plastic waste could heat homes.
The story is about a type of pyrolysis plant that takes the process further to produce hydrogen.  The story doesn’t actually use the word pyrolysis, and by talking about clean hydrogen energy it taps into the current “hydrogen economy” rhetoric that is being used by some people.

The information appears to come from the University of Chester website. But there isn’t much extra there either.  To me, it sounds like they may just be using a variant of the old coal syngas process – which requires steam and a carbon source to reduce water to H2 & CO.  In this case they are using mixed plastics instead of coal, and may also get CH4, amongst other gases.

They are talking about collecting the H2, for sale, and burning the rest of the off-gases to make electricty.  As such, this is basically an EFW (energy from waste) plant, that collects hydrogen as a byproduct.  It looks like the combustion products (including CO2) will still enter the atmosphere – so, arguably, like all EFW plants it is just displacing an equal amount of fossil fuel use.

At least it will consume a lot of plastic – preventing it entering the oceans – even if it does pump out CO2.

warrior
19/07/2019 at 13:22
1

I can see that any duckweed grown for food is going to need “clean” conditions, but the stuff grown for biofuels should also be good for wastewater remediation.

Many sewage treatment plants are currently building biodigester facilities to generate gas and make electricity.  Another stage of water cleanup from duckweed might also help to provide extra feedstock for co-digestion – possibly enhancing the methane yield.  The methane yield from pure sewage is not actually that good (although they process such a lot of crap that it is still worthwhile doing). Hence, at some plants they are also taking waste food to add to the digesters.

Unfortunately, some facilities seem to be using non-waste food, such as maize, for co-digestion – just because it is locally cheap.

In reply to: Making a buoy mould

warrior
18/07/2019 at 21:43
0

Hi @ckerstan,
Have a look at Rotomolding (rotational moulding).

warrior
17/07/2019 at 23:19
1

If duckweed is to be used on a large scale, as a biofuel feedstock – then we do need to imagine what that would look like.  One problem with current biofuel options is that people expect the crops to be grown “somewhere else” – so to not make any changes to their local scenery.  But most of the good land situated “elsewhere” is already being used to grow food – and so biofuel crops simply displace food crops.
For biofuel crops, we need to use “marginal land” – such as hills and mountains. What would that look like?  I’m guessing that for growing duckweed, terracing might just work – a bit like the way some rice paddy fields are arranged.

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warrior
15/07/2019 at 08:40
1

Just another paper for general perusal:

Growing duckweed for biofuel production: a review (PDF)
W. Cui & J. J. Cheng, Volume 17, Plant Biology. Special Issue: Duckweed ‐ Research and Application. January 2015

Viewing 30 replies - 1 through 30 (of 284 total)