Study: Single-stream is more wasteful, expensive

By Chrissy Kadleck | WRN correspondent

April 25 -- Sorted recycling systems win out over single-stream recycling in a head-to-head competition when the municipal playing fields are even, according to a research report that tracked outcomes in United Kingdom markets over a four-year period.

The study, which was published by 4R Environmental on March 28, provides an analysis of 65 bids between 2008 and 2012. It revealed that 51% of all recycling collection services resulted in curbside sorting, even though that system was only allowed in 45 of the 65 municipalities tracked. Overall, 28% were awarded to single-stream commingling and 21% resulted in dual-stream systems.

In 29 cases, there was a genuine competition between systems, said Andy Bond, director of 4R Environmental Ltd. and the report´s author. In those cases, 59% of the municipalities selected curb-sort, 31% selected dual stream, and 10% selected single-stream.

"And even if you count all the procurements that curb-sort isn´t allowed to tender for, it is still the most successful system because it´s got more than 50% of the procurement where a local authority has gone to the market to secure a service," said Bond. "Where the system is allowed, it won on 73% of the occasions. The next most successful was two-stream, and single-stream was by far the least likely system to win in a competition."

Bond, formerly the managing director of ECT Recycling, the largest social recycling enterprise in the U.K. when it was purchased by May Gurney in 2008, said the results confirmed what he has witnessed in the field during the past two decades.

"My experience was that curb-sort systems, by and large, were more economically successful in competition with commingled systems because they won more frequently," he said, adding that the study was also done to "to inform a debate that is ongoing where authorities and waste management companies claim that commingling is the only way to do [recycling] and it´s cheaper. The reality is there is not a lot of evidence to support that, and this is just another piece of evidence that says this assumption that they are making is actually wrong."

In fact, he has been involved in two recent cases where municipalities switched back to curb-sort recycling from single-stream because it was cheaper.

"There are at least four cases that I am aware of where councils switched back to curb-sort recycling from single-stream, and I was involved in tendering for two of them successfully," Bond said. "It was cheaper, and in order to win, you needed to be cheaper. The difference is significant. In one case, it was 1 million pounds a year for a relatively small local authority. So instead of $5 million, they were paying $4 million for the service. And recycling is only one component, but it is significantly cheaper."

Susan Collins, executive director of the Container Recycling Institute (CRI), said she found the research fascinating -- albeit not surprising.

"This study is really interesting because there are so many data points. They looked at dozens of procurement situations, so they are actually uncovering a pattern," said Collins, adding that CRI has for the past few years been researching and gathering data about single-stream systems in the U.S. "We have always expected to see that single-stream would be more expensive, because it yields less in terms of scrap value."

In fact, higher contamination levels in single-stream programs on average result in an overall loss rate of 22% to 27% by weight, according to research findings Collins published in February.

"What we found [over the years] was that single-stream is often reported as having the highest collection volumes ... but it´s not just the amount collected. It´s how much actually makes it into a manufactured product at the end of the day," she said. "With those higher contamination levels, the costs are higher for the mills and reclaimers, so of course the mills and reclaimers pay less for the output of single-stream then they do for cleaner materials."

Bond said curb-sort is a superior system for many reasons.

"There are a lot of environmental reasons why it´s better, particularly the quality of the materials, lack of wastage and the [carbon dioxide] outcomes are significantly better," he said. "It also happens to be cheaper as well, so the taxpayer gets a better outcome, too."

He said there is evidence that yields tend to be higher in commingled systems, but when you factor out the wastage at the materials recovery facilities, sometimes 25% of the material sold doesn´t get reprocessed because the quality is too poor.

"What the most important thing is how little waste there is at the end of the system," he said.

But can this report translate to single-stream programs and costs in the U.S.?

Yes and no.

Collins and Bond both concede that economics, geography and market density vary.

"I do know that there is a conversation that is getting increasingly louder that is saying that we have to preserve the quality of materials as we collect them and that needs to happen through greater separation at the source," she said, adding that the issue of separation was highly recommended in an international research study done by GreenBlue titled "Closing the Loop."

"It doesn´t mean you have to separate them into 40 different categories," Collins said, "but putting them all together has its disadvantages and all of the systems in Europe that have really high recovery rates also have a much greater level of separation than we do."

WRN correspondent Chrissy Kadleck can be reached at ckadleck@sbcglobal.net.

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