Wastewater and Sludge Analysis

The hydrolysis of solid matter is a key factor in the anaerobic digestion process, and optimizing this rate-limiting step can greatly enhance biogas production. Thermal hydrolysis has been thoroughly researched, with temperatures ranging from 60°C to 180°C, and various pre-treatment methods have been studied to expedite this crucial step. Low-temperature pre-treatments (under 100°C) have been shown to increase biogas production, while wet oxidative (WO) pre-treatment uses higher temperatures and an oxidizing agent such as oxygen or peroxide. WO pre-treatment not only reduces solid waste volume but also generates valuable organic compounds like acetic acid.

Our state-of-the-art HPR-40 DSA Membrane Inlet Mass Spectrometer (MIMS) technique allows you to monitor changes in volatile components during pre-treatment. In Figure 11, MIMS was utilized to track oxygen consumption and carbon dioxide production during the thermal pre-treatment process for four different substrates: coal, Kraft pulp solids, chicken feathers, and chicken processing waste. The graphs display variations in O₂ and CO₂ at 200°C (a), total O₂ consumption (b), total CO₂ production in oxidative (c) and inert atmospheres (d).

Furthermore, the research group observed the production of acetic acid in both oxidative (e) and inert (f) atmospheres. Importantly, the methane yield increased after pre-treatment at 140°C but decreased at a higher temperature (200°C).

Discover innovative wastewater and sludge analysis techniques, including thermal and thermo-chemical pre-treatment methods, that boost biogas production and contribute to a more sustainable future.

Figure 11 (a-f): Changes in O₂ and CO₂ when feathers are treated at 200˚C (a), total O₂ consumption (b) and total CO₂ production for all substances after 1h under oxidative atmosphere (c) and inert atmosphere (d) at various temperature. Acetic acid production under an oxidative (e) and inert atmosphere (f) up to 200˚C.