Moving Towards a Zero Environmental Footprint Dairy Plant

This paper sets out a vision for a fully integrated and systems approach to the recovery of water, nutrients, carbon, energy and waste streams within the footprint of a dairy plant. The Zero Environmental Footprint Plant (ZEFP) moves beyond the Zero Liquid Discharge (ZLD) model to one of resource recovery and closing the resources loops.

A ZEFP has minimal to zero measurable air, liquid and solid emissions into the environment by optimising the recovery and reuse of solids and liquids and use of renewable energy to reduce carbon emissions. In doing this, water and energy imported from sources outside the plant are minimal or avoided. Within a ZEFP model all waste streams are considered resources that can be recovered and reused within the dairy plant or by external stakeholders, with minimal to zero environmental consequences.

The concept for ZEFP incorporates:

• Biogas and co-generation of electricity
• Use of renewable energy
• Carbon neutrality
• Zero liquid discharge treatment of water and recovery of salts
• Biosolids and nutrient recovery to produce a fertiliser or soil improver product
• Minimal to zero production of intractable residuals

The benefits of a ZEFP are long-term reductions in water extraction, potential cost savings in energy use and waste disposal, regulatory compliance with more stringent environmental consent limits and recovery of resources such as nutrients, carbon and water. Other benefits include meeting increasing customer desire to minimise carbon emissions and the environmental impacts of the products they use.

A Zero Environmental Footprint Plant is a paradigm shift in how resources are viewed and used within the industrial food manufacturing setting. By applying available, proven technologies with a systems approach to optimise resource recovery, it eliminates or significantly minimises discharges and emissions to the environment and reduces the importation of energy and water.

This paper will outline case studies to demonstrate the technologies and systems available which can be used to achieve a Zero Environmental Footprint Plant. A current and future scenario is presented demonstrating the changes in processing required to achieve this paradigm shift.