Expansion of a paper mill’s treatment plant

Objective

Adaptation of the treatment plant to new treatment requirements in order to improve efficiency and wastewater management capacity in view of the activation of a new production line.

Critical issues

Although the existing plant was functioning correctly, it presented some critical issues related to the increase in input loads, both in terms of flow rate and pollutants. The main challenges to be addressed were:

• management of peak flow rates and organic loads;
• adaptation of existing treatment sections (water and sludge);
• optimization of energy consumption;
• improving the quality of the final treatment;
• limiting space and expansion costs.

Results

The functional analysis scientifically examined two alternative design scenarios, highlighting the advantages and critical issues of each, and providing the company with solid support for making decisions and guiding future investments. Scenario 1, which involved expanding aerobic treatment, offered a robust and easily manageable solution due to the availability of trained personnel. However, it also involved an increase in energy consumption and sludge production. Scenario 2 involved integrating anaerobic treatment and allowed for greater energy efficiency and reduced sludge production without the need for significant expansion. However, it required more complex management and specific training. The analysis therefore enabled the operational and strategic implications of the two options to be clearly assessed, supporting an informed, sustainability-oriented choice.