The paper and pulp industry is among the largest industrial users of water resources operating across the world. Typically, pulp and paper industry operations require on average about 54-70 m3 (18,000 gallons) of water per metric ton (2200 pounds) of processed paper goods. This water usage is staggering, and water is used in almost every single part of the pulp and paper manufacturing process. These paper mills produce significant quantities of both waste water and residual sludge waste from initial pulp digestion to pulp slurries, and washing the paper making machinery.

At least 80% of process wastewater from paper making operations include suspended solids, chemical oxygen demand (COD), trace heavy metals, recalcitrant chlorinated organic compounds, biological oxygen demand (BOD), color and bacteria among others.

In light of these issues, prioritization toward advanced wastewater treatment processes are required to handle these water conditions to optimize this wastewater for environmentally safe discharge or reuse. These viable solutions are specifically provided for pulp and paper mills to assist them in harnessing their waste water resources in a sustainable way while meeting ever changing regulatory guidelines.

Modular wastewater treatment implemented onsite is imperative in many cases due to the volume of wastewater and amount of contaminants in pulp and paper operations. Common treatment technologies include primary treatment for removal of larger suspended solids and particles, followed by coagulation and flocculation using either specialized electrocoagulation and/or specialized flocculants like Zeoturb bio-organic liquid bio-organic flocculant based on the treatment flow rate of the pulp and paper mill.

Additionally, biological treatment has been used along with tertiary treatment including advanced oxidation, activated carbon and membrane treatment systems which can allow for higher quality water that can be effectively reused in paper mill facility operations. This treated water can also be used to potentially recharge aquifers, which is particularly important in coastal areas where saltwater intrusion of ground water is an issue.

If you are researching strategies to optimize your paper mill facilities water consumption, I have included a few notable points that your facility can apply to enhance daily operations and reduce overall operational costs.

– Plant optimization audit

– Consistent care of plant systems

– Integration of advanced modular treatment solutions, including alternatives to the bleaching process.

Reducing water consumption is an ongoing process for pulp & paper facilities, that will require a commitment to sustainability. However, successfully deployed over time throughout the plant, this commitment will provide reduced overall operational costs for the company and enable these facilities to meet ever changing regulations.

Application Case Study (Pulp/Paper Industry)

Challenge

A large pulp and paper company producing various paper products wanted to sustainably treat their washing waste water prior to discharge to meet stricter regulatory compliance. The levels of BOD, COD, TSS, and trace metals were required to be reduced to allow for sustainable discharge with minimal environmental impact.

Raw BOD levels: 225 mg/l

Raw COD levels: 932 mg/l

TDS: 1599 mg/l

TSS: 756 mg/l

pH: 6.5-7.1

Solution

Genesis Water Technologies provided process consulting/design as well as building and supplying the specified pilot system solution in association with a local partner for a large pulp and paper plant operation. The system included specialized screen filtration, followed by clarification using a physical/chemical treatment including our Zeoturb liquid flocculant for reduction of trace metals, BOD, and COD with aeration, post filtration and introduction of Genclean for polishing disinfection and advanced oxidation. This was accomplished via a continuous batch process.

Results

The system solution was installed by a local project management/contracting firm with technical assistance provided by Genesis Water Technologies, Inc.

The optimal removal percentage efficiency results are listed below:

Treated BOD levels: 94% reduction

Treated COD levels: 90 % reduction

TSS: 97 % reduction

Capital cost and operation cost were minimized in this process as the chemical feed skids were calibrated to dose the Zeoturb accordingly and the post filtration and Genclean-Ind advanced oxidation process will be optimized for power consumption.

If required by changing guidelines, TDS reduction can be accomplished via RO membrane system.

The sludge production was minimized with a higher solids content that was easy to dewater, therefore, reducing associated disposal costs for the larger wastewater flow rates of these large pulp and paper mills.

The system has operated successfully within the water quality parameters set by the client to allow sustainable discharge of their wash water in the production of their paper products, which will assist to reduce the environmental impact of this paper mill on the surrounding environment.

Want to learn more about innovative treatment solutions for your pulp and paper operation? Contact the water & wastewater treatment experts at Genesis Water Technologies, Inc. +1 877 267 3699 or reach out to us via email at customersupport@genesiswatertech.com to discuss your specific application.