Hello from a plastic consultant
I work as a consultant for many plastic companies (mostly in the field of recycling and injection moulding), I think I’ll be able to help you out with any question or information regarding recycling process.
Also, I’d like to express a little concern I have regarding this project: cleaning and sorting of plastic.
Without these 2 previous steps, I really doubt this project has any chance to keep alive in the near future.
It’s always good to have input from an expert.
Hello Mr consultant i am from Nepal hub of mountains.since our cities are being tortured from different types of waste. which is disturbing our heavenly nature.after thinking seriously i want to turn my self as a recycler.It would be great help if u could help.
Hi @vincentvegas, thanks for donating your time to the cause.
The cleaning and washing is specially mentioned on the release of the v3 container workshop, it might not have been mentioned before. Clearly we try to separate by type of plastic, and even by colour. But how thorough do you think the cleaning has to be? Water and soap or other chemicals to wash them perfectly clean?
Also would it be too hard for ‘diy’ artists like this community (meaning we don’t recycle plastics in a heavily controlled industrial process) to create food-safe products? What do they need to be marked food safe?
Hasta luego, saludos
Hi @javierrivera, sorry for my late reply.
The cleaning and washing is specially mentioned on the release of the v3 container workshop
OK, probably I missed that.
But how thorough do you think the cleaning has to be? Water and soap or other chemicals to wash them perfectly clean?
It depends a lot on the type of output you’d like to get. For example as far as water bottle, I think soap-washed should be enough. But with other type of substance (like oil or bleach for example) it should be applied a better clean process. First of all to get an adequate raw material and produce better quality products, and then to avoid any damage to the extruder (you can find yourself changing the screw of the extruder quite often if working with dirty material).
What do they need to be marked food safe?
Forget about that, not even the industrial process can produce food safe recycled plastic (actually they are starting now with a new patent, but it still in the beginning. Until few years ago the FDA forbid all recycled plastic to be used in direct-contact with food).
Hello Vincent…I live in Northern California and work for a thrift store that supports hospice. Our dilemma is we lost our plastic recycling vendor when China stopped taking household plastics that our recycling facilities won’t take. Do you have any information on business’ that would be interested in this type of plastic to use in their recycling process. I am seriously thinking about starting my own business, but have no experience in this industry.
Hi Vincent. Can shredded plastic be cleaned and washed thoroughly or you need to have it cleaned and dried before shredding it?
ups, sorry didn’t read that before. Don’t know if you still need the information.
Sorry I don’t know any business that could be interested. You can still start your own, I advise you to get as many information as you can regarding the process for the plastic you’d like to recycle. Moreover you can buy 2nd hand machinery, which will save you some money.
It depends on the plastics you’re going to recycle. There are process where is better to clean plastic before, others where is better after and others where you need to wash it, shred it and then wash it again.
Hello Vincent! Do you know what type of chemicals are used for washing plastic waste? I’m mostly leaning towards HDPE and LLDPE.
This will be on a medium/small scale of around a few kilos per hour.
My thought process is to shred the plastic and wash it afterwards. Then let it dry and then pulverize the plastic before rotational moulding.
Thank you for your time!
It depends on the condition of the material, in the recycling industry usually plastics are separated in 2 groups: post-industrial (which is considered “clean” plastic) and post-consumer (“dirty” plastic). In your case I don’t know which kind of plastic are you inclined to use, but I guess it should be enough by using a solution of caustic soda (around 2%) in hot water (85ºC). You can also add a detergent to the solution. Very important is to employ a “shake-movement” while washing (same operating principle as in a washing machine), which will improve the result.
After the washing process, the plastic should be rinsed to eliminate any trace of the substances previously used or impurity.
It is also very important to properly dry the washed plastic before pulverize it, in the case of LDPE it is a good idea to use also a densifier.
To use recycled plastic in a rotational moulding process, it is important to know the characteristic and fluidity of the plastic used. To improve the output it may be a good idea to add additives and/or pigments.
Good luck with your project
Hi @vincentvegas – thanks for contributing to this forum.
One thing that has been concerning me about the idea of collecting and processing all this post-consumer plastic waste, and especially waste that has been lying around in landfills, and as general litter, is the threat of people developing Leptospirosis.
One of the more severe forms is known as Weil’s disease and is usually spread by rodent urine. Discarded plastic food and drink containers will attract rats due to the smell of residues. The rats are highly likely to urinate on the container, after investigating it as possible food.
I think it makes it even more important that these items are not only cleaned, but disinfected after collection – and that street/landfill collected items are treated with caution (e.g. handled with gloves).
Hope everything is well with you.
I was wondering about stickers and stuff on the plastic.
Is there a way to clean them off after the shredding has been done and then sorting it out or is that always done before shredding?
Do you have any intel regarding this?
Well, generally speaking the process goes as follows:
collection of plastic and possible grouping for material and color; pre-washing; label remover; metal separator; categorization; shredder; washing; dryer; silos.
So usually labels are removed before shredding, for an industrial process there is a machine that do that automatically (for example: https://goo.gl/EVKeZ1)
Ups, sorry. Didn’t see your question.
I’d always take precautions with any kind of fumes coming from melted plastic, working in a good ventilated place, wearing a mask…should be a standard approach.
As you say there are “more toxic” kind of plastic, for example PVC, but take into account that also the ink of printed plastic may be very dangerous. That means, unless you are working with clean plastic, you should always do your work as safe as possible and thus take all precautions needed.
Hi, so the fumes are almost always toxic? Toxic to humans but what about the enviroment? We will be recycling plastic, wich is a good thing, but is it a danger to the air and enviroment around us?
What do you have to do to make it a save workspace?
What do you have to do to make it safe for the air around us? Filters or..?
I’d always take precautions with any kind of fumes coming from melted plastic, working in a good ventilated place, wearing a mask…should be a standard approach.As you say there are “more toxic” kind of plastic, for example PVC, but take into account that also the ink of printed plastic may be very dangerous. That means, unless you are working with clean plastic, you should always do your work as safe as possible and thus take all precautions needed
Hi, so the fumes are almost always toxic?
No, that’s not what I said. I’d get all precaution just in case but, unless you are working with PVC, shouldn’t be a big concern.
For example, safety footwear is really needed in all warehouse? Probably not, but just in case lot of companies force workers to wear them.
What I wanted to say is better safe than sorry.
Enviroment has much bigger concerns than melted plastic
Yess, I know the environment has much bigger concerns but I’m starting up a workspace and I got this question and I want to give the right answer so..
Do you know wat the fumes do to the air and environment?
Thank you! 🙂
Fumes of melted plastic are not a risk for enviroment.
Moreover you can see it from the other point of view: if you don’t melt plastic, the plastic can’t be recycled. If it’s not recycled, in the best case scenario plastic would be burried in ladfills or burned down (burned! not melted!) in some incinerator, which is lot more dangerous to the enviroment than some little fumes from melting.
You can recylce (melt) your plastic without any worries 🙂
Great , thanks Vincent! 😉
Do you know of any good Introductory level resources for learning about plastic manufacturing? I’d love to get a slightly more technical understanding of temperatures, compression pressures, etc… for different types of plastics.
Hello @vincentvegas ! I’m currently working on a project with a logistics company and they used large amount of stretch films everyday which are used to wrap the pallets. I supposed they are made of LLDPE. I’m thinking of recycling them and turning them into plastic sheets. Could you please advise on the process such as the machines used, methods or even additives to be added? Thank you so much and looking forward to your reply soon.
Plastic Consultant, which companies do you work for?
You believe the sorting may become a failure? I don`t understand your consultation, please elaborate.
Sorry, can’t tell you exactly where to find that info, but by searching in the web should be enough to get a better idea of all the process and technical details
Yes, that’s LDPE or LLDPE. The process is always the same: shred, clean, dry, compact and re-palletizing. For this material it is important to pay more effort/attention in the dry and compact process. Do you want to recycle it by your own or in an industrial way? I mean, it is just a personal project or are you thinking in operating as a business?
My name is Vincent, not Plastic Consultant XD
I prefer not to mention the company I work for, I don’t think this is the appropriate place.
How did you come to the conclusion that “sorting may become a failure”? Please elaborate 😉
You must be logged in to reply to this topic.