Upflow reactor with anaerobic sludge blanket - compact & efficient biogas production

The ALMA BHU UASB (Upflow Anaerobic Sludge Blanket) reactor is an anaerobic wastewater reactor for treating industrial wastewater with medium to high organic loads. It is one of the most proven anaerobic processes worldwide and is used in particular when robust, energy-efficient, and durable solutions are required.

Functional principle of the ALMA BHU UASB

In the ALMA BHU UASB, wastewater flows from bottom to top through a sludge blanket made of anaerobic biomass. The organic substances are broken down by microorganisms and converted into biogas (methane).

The rising gas bubbles ensure natural mixing without the need for mechanical agitators. In the upper part of the reactor, a 3-phase separator separates:

• the biogas produced

• the treated wastewater

• the biomass retained in the reactor

Role of the UASB in the plant design

The ALMA BHU UASB often serves as:

• central anaerobic stage

• economic pretreatment before aerobic systems

• CSB reduction stage with simultaneous energy recovery

Summary
The ALMA BHU UASB is an anaerobic upflow reactor that breaks down organically contaminated wastewater, produces biogas, and operates without mechanical mixing.

The ALMA BHU UASB is designed for industrial wastewater with medium to high COD concentrations and is particularly suitable for applications with stable or moderately fluctuating loads.

Suitable CSB areas

Typical conditions of use are:

• CSB concentrations from approx. 800–1,000 mg/l

• easily biodegradable organic substances

• continuous or evenly buffered wastewater accumulation

Maximum room load

The ALMA BHU UASB achieves organic loadings of up to
15 kg COD/m³·d.

This puts him:

• below the power density of an EGSB reactor

• significantly above classic large-volume bioreactors

This load allows for economical and stable wastewater treatment with moderate space requirements.

Typical industries of application

• Food and beverage industry

• Dairies

• breweries

• Sugar and starch industry

• Process wastewater with uniform composition

Summary
The ALMA BHU UASB is suitable for COD concentrations above 1,000 mg/l and allows for space loads of up to 15 kg COD/m³·d.

The ALMA BHU UASB features a simple, robust, and proven reactor geometry that is specifically designed for continuous industrial operation.

Sludge blanket with high biological activity

The anaerobic biomass forms a stable sludge layer with:

• good sedimentation capacity

• high biodegradability

• low discharge tendency

Efficient 3-phase separator

The integrated 3-phase separator ensures:

• Safe separation of gas, water, and sludge

• low biomass losses

• clear flow quality

Low energy and maintenance costs

Since no mechanical agitators are required:

• the energy requirement is very low

• maintenance requirements are significantly reduced

• plant availability increases

Summary The ALMA BHU UASB utilizes a stable sludge blanket and an efficient 3-phase separator for low-energy and low-maintenance operation.

The ALMA BHU UASB is particularly advantageous when operational reliability, simplicity, and durability are paramount.

Key advantages at a glance

• Proven method used worldwide

• Room load up to 15 kg COD/m³·d

• Very low energy consumption

• No mechanical agitators in the reactor

• High operational reliability

• Long service life

• Numerous references in the industry

Compared to high-load systems such as EGSB, the UASB is:

• less complex hydraulically

• more tolerant of operational deviations

• particularly suitable for even inflows

Summary
The ALMA BHU UASB impresses with its simple technology, low energy consumption, and high operational reliability for medium to high COD loads.

The use of an ALMA BHU UASB is particularly useful when:

• a robust anaerobic base level is required

• Wastewater composition is relatively constant

• Energy efficiency is a priority

• Investment and operating costs should be minimized

Economic benefits

• Reduction of COD load prior to aerobic post-treatment

• Savings in ventilation energy

• Biogas production for own energy supply

• Low maintenance and spare parts requirements

The UASB is often the most economical anaerobic solution when extreme space constraints are not an issue.

Summary
The ALMA BHU UASB is economically viable for constant, easily degradable wastewater and moderate space loads of up to 15 kg COD/m³·d.

The ALMA BHU UASB can be flexibly integrated into existing wastewater treatment concepts:

• as a preliminary stage before aerobic treatment stages

• in combination with neutralization, CP plants, or flotation

• as part of modular ALMA complete systems

Thanks to its simple design, the reactor can:

• be bolted or welded

• be adapted to existing hydraulic concepts

• can be easily expanded or retrofitted

Summary

The ALMA BHU UASB can be flexibly integrated into existing industrial wastewater treatment plants as an anaerobic pre-treatment stage.