Wastewater treatment plant at a greenfield brewery

Greenfield Grupo Modelo Brewery

Description

LUCAS® UASB

Location

Yucateca, Mexico

Capacity

Treated wastewater: 4,320 m3/d
Organic Load: 28 tons COD/d

AB Inbev Yucateca Mexico

Sustainable beer production

Waterleau recently built a state-of-the-art wastewater treatment facility for Grupo Modelo’s greenfield brewery located in Yucateca, Mexico. The primary objective was to help Grupo Modelo reduce its environmental footprint. Waterleau’s scope included the plant design, construction and commissioning, as well as the start-up and operation assistance during the first years.

AB Inbev Yucateca Mexico

Biogas recovery and nutrient removal

The Yucateca wastewater treatment plant is designed for treating up to 4,320 m³/d wastewater and 28 tons of COD/d with up to 70ppm of Phosphorus.

The design integrates BIOTIM® UASB anaerobic technology for biogas production, including a set of aerobic, anaerobic and anoxic lagoons for biological treatment of the brewery’s industrial effluent, and Bio-P removal, followed by a physico-chemical post-treatment to further reduce Phosphorus levels.

Design objectives of the Yucateca Grupo Modelo wastewater treatment plant

Treatment efficiency : Maximum COD reduction at minimum energy cost
Biogas Yield : higher biogas production
Compliance: P and N removal in accordance to more stringent regulation

LUCAS® UASB : reducing waste and energy cost

Compared to alternative treatment technologies, Waterleau’s BIOTIM®anaerobic treatment offers several key advantages:

High efficiency of COD removal: up to 85%. in combination with aerobic post treatment up to 95%
Energy saving: BIOTIM® anaerobic treatment does not require any oxygen
Solid waste reduction: due to high removal efficiency, significant reduction of aerobic sludge during aerobic post-treatment
Green energy production: biogas from anaerobic treatment replaces natural gas from the grid, used for firing the boiler room
Valuable by-products: production of granular sludge that can be monetized as a resource for starting-up anaerobic reactors
Robust design, proven technology, simplicity of operation
Low chemicals consumption

A BIOTIM® biogas scrubber uses activated sludge from the wastewater treatment process to remove the remaining phosphorus from the biogas, turning it into a substitute for natural gas.

Nutrient removal in aerobic post treatment

Apart from the removal of the remaining COD, bio-N-removal and bio-P removal processes also take place in the aerobic post treatment step: anaerobic bio-P, denitrification and nitrification compartments are integrated in the aerobic bioreactor.

Bio-P take-up takes place in a separate zone: thickened sludge from the decanter is recycled to the bio-P compartment and brought into contact with feed water (BOD). The activated sludge accumulates PO4 under anaerobic conditions.

In order to reduce the total phosphorus from the effluent stream, a physico-chemical polishing step is necessary. The following steps are necessary to remove Phosphorus

Coagulation: coagulant dosing in the effluent from the secondary clarifier
Flocculation: polymer dosing into the flocculation tank
Clarification: The clean, treated water is separated from the physico-chemical sludge by gravity by clarification. P-holding sludge is removed from the bottom of the decanter, and discharged outside the brewery.

With P-levels in the final effluent stream below 5 ppm, the treated wastewater complies with discharge regulation.

Future-proof design

The initial plant footprint takes into account future expansion of treatment capacity. The design foresees working in 2 identical and parallel lanes. During construction, basic civil works for the second LUCAS® UASB have already been prepared.

The plant is also prepared for water recovery. Membrane technology (e.g., reverse osmosis) and disinfection (e.g. ultraviolet treatment) will help reduce the sourced water to beer ratio.