A report on China's book market last year published by Beijing Open Book Co Ltd, a provider of data and information for the publishing industry, said the book market in China had turnover of 803,200 million yuan last year, 14.5 percent more than in 2016. The increase indicates that the book market in China is still growing.

Hu Xiaoming, 29, who runs a book shop in Tianjin and has been buying secondhand books for several years, says he enjoys wandering around old book stalls along the street and coming across good old books that he likes. With the growing business of online bookstores, he began to buy secondhand books online.

"It's convenient and the books are clean, which people appreciate," he says.

Hu suggests that these days people are overburdened with material possessions, which helps make recycling an attractive proposition.