brunel university london and mission resources ltd., a group of companies focused on the waste industry, are working together to develop a low temperature pyrolysis treatment to decompose household wastes into clean, sustainable fuels to heat water for homes, according to a report on the university website.

brunel university and mission resources worked together on the heru project. (brunel university london)

the self-contained home energy recovery unit (heru) could save families as much as 15 percent on fuel bills and also provide an answer to the world’s waste crisis. the researchers believe that it could reduce the carbon footprint for waste disposal in the u.k. by as much as 70 percent.

the unit works with proprietary heat pipe technology that spreads the heat evenly across the pyrolysis chamber, which greatly reduces the energy required to heat the chamber and makes it more controllable. the heru heats to 300°c, which is much lower than similar technologies.

the mission resources website explains, “once the pyrolysis process is complete, the internal chamber moves away from the heat pipes, oxygen is then introduced into the chamber to ignite the char compound. the exhaust gasses then pass through a heat exchanger unit, before a gas filtration cleans the exhaust prior to being vented to the atmosphere.”

the three output materials from this process are char, which is solid fuel that is safe to handle and can be burned to generate heat, pyrolysis oil, and gas. mission resources insists that households can generate hot water from the heru and could even be incorporated with solar panels to lower its carbon footprint further.

the research behind heru was published in energy. the abstract from the report read:

“a heat pipe based pyrolysis chamber has been developed and tested as an efficient, cost effective and space saving municipal waste treatment unit. the performance of the chamber was evaluated based on the temperature distributions inside the chamber, its electricity consumption and the chemical characteristics of the final pyrolysis products (bio-chars and pyro-oils) obtained from the process and validated by three test runs. in all the three tests, the type of waste treated was municipal waste obtained from households.

“in addition, special cases of challenging waste configurations, such as mixed domestic plastics and pvc are reported. the chemical analysis of the pyrolysis and the ash residues from the municipal solid waste showed no toxic elements in their composition.

“the main component of the char was calcium, the fluid oil obtained from the initial stages of pyrolysis had a similar composition to that of water, while the dense oil produced during the final stage of the process showed traces of iron and a potential composition match to commercial additive oils.

“the chemical analysis of the chars and ash obtained from the mixed domestic waste showed no toxicity for the mixed plastic char but a potential toxicity of the pvc char due to the existence of lead and chlorine. calculations regarding the coefficient of performance (cop) of the heat pipe based pyrolysis unit indicated that the cop decreased with the increase of moisture content of the waste stream.

“for 0% moisture content in the waste stream the cop of the unit was 9.4 and the carbon footprint of the unit was 0.0782 kg co₂e per kg of treatment. on the other hand, for a maximum moisture content of 100% the cop was 0.53 and the co₂ emissions were 0.3873 kg co₂e per kg of treatment.”