Chinese scientists turn black coal by-product into white paper
- After nearly a decade of research, fly ash could reduce amount of wood pulp used in paper production
More than 2,000 years after the invention of paper in China, the country’s scientists are claiming another breakthrough that replaces its key ingredient with the dirty waste from coal-fired power plants.
The result – which is almost indistinguishable from paper made from wood pulp – achieves a more than 90 per cent match to pure whiteness, despite being made with the black fly ash produced from burning coal.
The process has passed stringent tests in real production lines and is ready for mass application, with some Chinese paper mills now able to replace nearly half the wood fibres in their products with the chimney waste, according to scientists involved in the government-funded research programme.
The breakthrough has come nearly 10 years after Professor Zhang Meiyun, from the Shaanxi University of Science and Technology, and her colleagues first proposed that calcium silicate in fly ash could be used as a filler in paper.
The new product addresses two problems – the environmental impact of the global industrial demand for timber and how to dispose of millions of tonnes of fly ash each year.
