Systematic industrial decarbonization through heat integration and high-temperature/steam-generating heat pump- A case study in agrochemical sector
This study demonstrates systematic decarbonization at a Swiss agrochemical site, combining pinch analysis with different temperature-lift technologies: mechanical vapor recompression (MVR), high-temperature heat pumps (HTHPs), and steam-generating heat pumps (SGHPs). The focus was placed on the site's largest steam consumer (29 % of total), where practical barriers (low source temperatures, capacities below commercial thresholds, chemical compatibility, and ATEX requirements) limited direct heat pumping potential. A networked solution was developed aggregating multiple low-capacity heat sources through an intermediate fluid circuit, creating a consolidated flow suitable for commercial-scale upgrading. The upgraded heat is redistributed to multiple sinks efficiently at varying temperatures through a second network. A mixed-function HTHP-SGHP configuration maximizing steam production (6 barg) and pressurized water (120 °C) emerged as optimal fit for this case-study, achieving 26 GWh thermal energy savings (13.3 GWh net), 67 % steam reduction in the analyzed plant (20 % site-wide), and 12 % total site CO2 reduction with non-fossil electricity. This work advances industrial heat recovery through: (1) transforming scale mismatches into advantages via strategic networking; (2) prioritizing electrification-based heat pumping over direct integration; (3) enabling steam injection for operational independence; and (4) considering multiple heat output with flexible ratios to reduce exergy losses.