Hacker News new | ask | show | jobs
by GeoffIsTheBest 2378 days ago
I was part of a software project for BHS several years ago. We were taking the cad models for a entire plant and rendering them in the web with info/marketing media for each module. The speed that they could sort material at different stages was incredible. I don't remember seeing a single "robotic arm" picking anything. It was all air and mechanical sorting. Very cool stuff. They should have videos of most their modules on their site for the curious.
2 comments

The first recycling robot was installed only three years ago.[1] There's been considerable progress since then. BHS is now installing and reselling the MAX-AI robotic picker, which seems to be a recent addition to their product line. This is out of the experimental stage and in use at high-volume sites. Expensive up front, about $200K each and $160K for installation and integration. Each one replaces about 2 people, plus the robots can run 2 or 3 shifts, so payback time is maybe 3 years.

There are some VC-funded companies in this area, but the vision/AI part is pretty much solved. It's getting the mechanical systems to be robust enough in a very dirty environment that's hard.

The big insight is that most of the separation has to be done by cheaper processes operating on the bulk material stream. The robotic system is just to pull out stuff that didn't get sorted correctly by screens, drums, shakers, magnets, blowers, and vision-based air jet sorters. An all-robot system is too slow and too expensive, but quality control robots for getting from 5% contamination to 0.5% contamination are cost-effective. Here's a good video of the whole process.[2] 70 tons an hour.

That makes it possible to get contamination levels down to China's new standards and the ones of US plants which can use the stuff. "Because of China's voracious appetite for all types of U.S. scrap exports over the past 20 years, MRFs "had the luxury of being able to sell the mixed rigid plastics [and] mixed paper without a lot of sorting and quality control." ... "Some materials are up in price … PET is actually increasing. It's a supply and demand thing," Butler said. "For the most part, if you can separate that material, there are domestic markets for that right now."[3]

So, in the recycling industry, some are whining about China's policies and others are fixing the problem, shipping products, and making money. It's small and medium sized cities that can't keep up. The big cities have big plants with multiple 70 ton per hour processing lines with the machinery running 2 shifts a day, and direct deals with companies that can use the plastics, metals, etc. A small town doesn't generate enough recycling to do that, and trucking unsorted material long distances is too expensive.

[1] https://resource-recycling.com/recycling/2019/05/07/how-recy...

[2] https://youtu.be/4FpsH_ETT7c

[3] https://www.wastedive.com/news/china-contamination-standard-...

Very insightful and cool to hear about new tech making it into the MRFs. I was impressed back in~2014 so I bet there are way neater techniques now days.
Mechanical sorting (like shoe sorters) is very effective for discrete objects. Really cool to see stuff flying down a belt at 20mph+, get scanned/imaged from all sides, then thrown down one of 50 chutes without stopping.