A METHOD FOR REDUCING THE ENERGY CONSUMPTION AT THE REFINING OF A PULP SUSPENSION IN A PAPERMAKING PROCESS AND USE OF SODIUM BICARBONATE IN PAPERMAKING

摘要

The invention relates to a method for reducing the energy consumption at the refining of a pulp suspension in a papermaking process. The reducing of the e nergy consumption is provided by treating said pulp suspension with non-stoichiometric sodium bicarbonate. Due to the treatment with sodium bicarbonate the calcium hardness value of the said pulp suspension is decreased to a level having an advantageous ef fect on the energy consumption and at the same time the pH value is adjusted and maintained at the desired level in the refining and preferably also throughout the subsequent paper making. The invention also relates to use of non-stoichiometric sodium bica rbonate in the papermaking process.