SANTIAGO, Dec 4 (Reuters) - Ceibo, a Chilean mining startup, is promising to improve copper production with less water and is aiming to expand tests to Canada, the United States, Mexico and Peru, the company's CEO Cristobal Undurraga told Reuters.

The technology involves a chemical leaching of primary sulfides to extract copper. Leaching is currently used to extract copper from surface-level oxides while sulfides deeper in the earth are extracted through concentrators and smelting, which is slower and more water intensive.

"Although the results will depend on the characteristics of the mineral, the analyzes we have so far show recoveries of up to 75% in primary sulfides," said Undurraga, compared to a 31% recovery rate through concentration.

The process is faster than the current concentrator and smelting method and Undurraga says it wouldn't require additional infrastructure. The firm is also working on a solution to reduce dust on mining roads, an environmental and health concern.

Water has been a key issue for miners in Chile, world's largest copper producer, with key mines seeing production hit by a devastating drought that's plagued the country for more than a decade.

Ceibo raised $30 million in June, led by American Fund Energy Impact Partners, to scale the technology to an industrial level.

Investors such as BHP Ventures, CoTec Holding, Audley Capital, Orion Industrial Ventures, Unearth Capital and Opalton also participated in the capitalization round.

Undurraga said the company is focused on executing a plan for the raised capital that involves "scaling our technologies by building a test plant and hiring a science and development team in Chile and abroad."

He added that the company aims to contribute an additional 1 million metric tons of copper to the 26-million ton global market, amid the lower supply expected for the coming years.

(Report by Fabián Andrés Cambero; Writing by Alexander Villegas, Editing by Franklin Paul)