Trash sorter may be the most unpleasant job in the world.

It's smelly and boring but critical to the efficient elimination of waste.

The job exists because people throw all types of garbage into the same bin. Trash trucks take everything in the bin and pour them onto a conveyor belt. The belt rolls with the pulley in front of dozens of workers, whose job is to sort bottles from boxes, among other things.

And despite the move to automate many low-skilled jobs, trash sorter is still in demand.

Garbage comes in all shapes and sizes and requires human handling, and it can be dangerous.

According to a study released by the University of Illinois, recycling workers are more than twice as likely to be injured at work as the average worker. Seventeen American recycling workers died on the job between 2011 and  2013.

Some recycling companies have turned to robots as a solution. Nick Morell, the recycling coordinator at District of Los Angeles County Sanitation, said his agency recently acquired a robot called Max-AI to reduce the labor cost and increase the efficiency of quality control.

The sanitation station currently relies on both human labor and optical sorting machines to produce cleaner trash. The traditional optical sorter filters trash based on color and material, and it does not always make the right decisions. Recycling workers have assist, standing next to the conveyor belt and resorting misidentified items.

Max-AI, however, is able to make better decides on which bottles to remove from the line, requiring less human intervention.

Created by the machinery maker Bulk Handling System (BHS), Max identifies recyclables much the same way as a human. It goes through a process called "deep learning" where it reads through hundreds of thousands of images to learn to "think out" the correct identification, according to Peter Raschio, the marketing manager of BHS.

BHS has three sites in the U.S. and three in Europe. It introduced Max-AI as a quality control system for recycling purposes in April 2017. Before that, the technology was used in the food industry.

Athens Services in the Sun Valley, a waste management company, was the first customer in the United States to install Max. According to its facility manager Jonny Stevenson, 46 workers work each shift in tandem with Max. Before Max, there were 55 sorters on the line, Stevenson said.

"I would say Max increased efficiency by 40 percent, compared to a human sorting system," he said.

The AI sorter even goes beyond the border to Europe. Three waste management companies in the U.K. and Ireland have invested in Max-AI to upgrade their processing lines. And orders are piling up at the headquarter of BHS in Oregon.

Max-AI is sorting trash in a waste management company. (Filmed by Keyu Huang)
Max-AI is sorting trash in a waste management company. (Filmed by Keyu Huang)