Local manUre and agri-food waste treatment for bioGAs and biofertiliZers production from Zero waste and circular economy perspective

Introduction

LuGaZ aims to create a sustainable zero-waste facility that manages organic and non-hazardous wastes generated primarily in the dairy sector value chain. The project also seeks to create opportunities for other agri-food industries in the area to manage their residues.

Project Overview

The project proposes an ambitious facility that combines several innovative technologies:

1. A biogas plant with an innovative low-scale upgrading system.
2. Liquid treatment of digestate for water recovery at low cost.
3. Solid treatment for fertiliser production across industrial symbiosis.

Nearly 55,000 tonnes/year of residues will be collected in the facility to generate biogas containing methane. This biogas will be captured, cleaned, upgraded, and injected into the natural gas grid.

Waste Management and Fertiliser Production

The digestate will be separated into two fractions:

• A solid fraction to generate a stabilised organic fertiliser for the primary sector, compensating for the manure sent to the LuGaZ plant.
• A liquid fraction that will be treated to recover reusable water in industrial applications.

The relative greenhouse gas (GHG) emissions avoidance due to LuGaZ operations during the first 10 years amounts to around 85%.

Innovative Technologies

LuGaZ goes beyond the commercial and technological state-of-the-art by introducing a first-of-a-kind combination of waste treatment technologies for the agri-food production value chain:

• OPTIBLENDER: A specialised software for the online control of anaerobic digestion that ensures the stability and quality of the digestate produced through co-digestion mixtures optimisation.

• NIDUP: An upgrading system specifically designed for small-scale applications, highly competitive due to its low operational costs, capability of coping with high hydrogen sulphide (H2S) concentrations, and potential to minimise reagents/consumables needs.

• DEPURGAN/AQUATEC: A low-cost solution for liquid treatment based on an electrocoagulation all-in-one solution.

Contribution to Climate Neutrality

LuGaZ contributes to achieving European climate neutrality by 2050 by producing high-quality biomethane to be directly injected into the natural gas grid. The project combines waste management with renewable energy production, which, along with biogas and the reduction of methane emissions from open manure storage and landfills, helps make treatment affordable and energy efficient.

Additional Benefits

It is also possible to obtain an added value product (fertiliser) and preserve natural resources through water recovery. LuGaZ has the potential to scale up by:

1. Increasing the size of individual integrating technologies (higher volumes of agri-food waste streams to be treated).
2. Replicating the Zero residue plant in new areas at Galician and Spanish levels.
3. Applying this model throughout Europe.

Economic Impact

LuGaZ’s innovative integrated scheme will play an essential role in the dynamisation of the primary sector by creating employment in rural areas. It actively participates in creating an innovative regional model of circular economy based on waste-to-energy principles. Additionally, it offers a practical waste treatment solution for rural areas, reducing transport costs and carbon footprint.