Integration of electrolysis to produce hydrogen and oxygen in a pulp mill process

The pulp and paper industry faces demand for totally carbon free production. Due to local conditions, there are challenges to sell produced additional electricity. A novel way, generating hydrogen and oxygen through the electrolysis of water can decarbonize the largest fossil carbon dioxide producing equipment, the lime kiln. The oxygen produced can be used for generation of bleaching chemicals, and also for effluent treatment. The operation and capacity of the recovery boiler can be improved by oxygen use. Using excess electricity of a typical, large South-American pulp mill, 73% of the heat demand of the lime kiln can be covered with hydrogen and the produced amount of oxygen exceeds the mill's oxygen requirement. The profitability of the integration depends on the other possible uses for electricity. When sales price for electricity is low or purchased oil price is high electrolysis can decrease the operating costs of a modern pulp mill.