Simon Harvey. Energy technology, Chalmers. Towards a Fossil-free Industrial Sector Activities at Chalmers 28 March 2017

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1 Simon Harvey Energy technology, Chalmers

2 Energy Efficiency in Industry Simon Harvey Professor of Industrial Energy Systems Division of Energy Technology Chalmers University of Technology Göteborg, Sweden

3 Long-term development of industrial processes for resource-efficient and carbon-lean production Energy efficiency is strategically important for all options! Increased use of excess process heat Renewable energy sources Energy efficient processes Carbon capture and storage/reuse Electrification including electrofuels and electrofeedstocks Renewable and/or recycled feedstock Integration with ecoindustrial parks and/or regional energy systems

4 The potential of energy efficiency Contribution of energy efficiency

5 Improving industrial energy efficiency delivers multiple energy and non-energy benefits to the energy user, the energy supply system and the economy Job creation, improved productivity, competitiveness and economic development Improved local environmental conditions e.g. air quality Energy efficiency should be considered as an energy resource in the same way that supply side resources are Enhanced energy security reduced energy imports reduced burden on electricity generation and distribution systems Major reduction of greenhouse gas emissions

6 A structured approach to improving energy efficiency in industrial facilities Energy efficiency Housekeeping Control systems Improved unit operations Process integration Alternative processes Housekeeping Good maintenance Turn off unused equipment Improve insulation Reduce waste, leaks, idle time Time

7 Energy efficiency Housekeeping Control systems Improved unit operations Process integration Alternative processes Time Control systems Predictive maintenance and condition monitoring Variable speed drives Control loop tuning Process can operate closer to its designed control limits

8 Energy efficiency Housekeeping Control systems Improved unit operations Process integration Alternative processes Improved unit operations Use compact heat exchangers Enhanced heat recovery Replace inefficient pipe work and/or pumps Install waste heat recovery boilers, pre-heaters and economisers Install variable speed drives Time

9 Energy efficiency Housekeeping Control systems Improved unit operations Process integration Step changes in process design and/or energy supply Systems approach Process integration Recover heat from one process to be reused in another Process intensification De-bottlenecking / uprating Overall plant or site-wide optimisation Time

10 Energy efficiency Housekeeping Control systems Improved unit operations Process integration Step changes in process design and/or energy supply Time Innovative design Combined heat and power Advanced heat pumping New process technology incl. electrification Energy-efficient separation (e.g. membranes) Overall plant or site-wide optimisation Eco-industrial parks Deliver excess heat to a district heating network or other off-site heat sink

11 Process integration for identifying energy efficiency opportunities in industrial processes Process integration: analysis and implementation of opportunities to maximize the efficient use of energy, water and raw materials by looking at interactions between the system parts. Heat integration investigates opportunities to recover heat from process heat sources (a.k.a. hot streams) to cover the process heat sinks (a.k.a. cold streams). Pinch Technology is the set of tools for estimating process minimum hot utility and cold utility targets and for designing heat exchanger networks to achieve maximum heat recovery Typical potential savings Oil refining: 10-25% Petrochemicals: 15-25% Iron and steel: 10-30% Chemicals: 15-35% Food and drink: 20-35% Pulp & paper (15-30% of total steam usage) (Economic potential in % of total fuel purchases)

12 Timing issues for efficiency studies of industrial energy systems in transition Typical time-frames for selected decarbonization measures

13 Process integration studies for strategic decision-making in industry Expected/possible increases in future costs associated with CO 2 emissions and energy prices will require more advanced technologies and systems Possible developments mean opportunities for more radical system changes The time perspective of changes becomes more important More need for B2B cooperation and new business models

14 Energy efficiency research at Chalmers: Process Integration activities In collaboration with:

15 The chemical complex in Stenungsund Borealis World leader for polyethylene for high voltage cables and piping Supplies district heating to the local community Inovyn PVC for the building and medical sectors Cooking chemicals for the pulping industry AkzoNobel Specialty chemicals for a variety of applications, e.g. detergents, pharmaceuticals, paints and road surfacing Aga Leading supplier of industrial gases Perstorp Specialty chemicals for the construction and automotive industry RME Biodiesel Supplies district heating to the local community

16 Stenungsund complex: Production and emissions data Year kton CO 2 41 kton 531 kton 43,6 GWh 390 kton CO 2 54 kton 206 kton 113 kton 1230 kton CO kton CO 2 56 kton 84 kton (??) 590 kton 11 kton 636 kton 115 kton 110 kton 111 kton 47,4 GWh CO kton TOTAL Emissions of CO 2 approx. 900 kton/yr

17 Quantification of heat recovery potentials Level 1: what can be achieved at the individual process plant level? Cracker Current hot utility usage: 122 MW (excl cracker furnaces) PE Level 2: what can be achieved by exchanging heat between plants, i.e. adopting a side-wide approach?

18 Basic Concepts of Pinch Analysis Heating T Heating Process Pinch Depends on T min 160 Minimum heating demand Feedstock El P r o c e s s Products El Energy balances T ( C) Hot streams Cold streams 20 Cooling Process streams Cooling Q Minimum cooling demand Maximum internal heat recovery Energy analysis

19 Heat energy savings targets for individual process plants Heat energy savings targets adopting a total site perspective Cracker Combined mimimum heating requirements = 77 MW Kracker THEORETICAL HOT UTILITY LOAD TO BE COVERED BY FIRED BOILERS = 0 MW PE Total combined savings potential = approx 45 MW Polyeten HOT UTILITY SAVINGS TARGET ADOPTING TOTAL SITE APPROACH = approx 122 MW!! (i.e. 3 * target that can be achieved by measures at individual plant level)

20 How can this be achieved? Site-wide circulating hot water system(s) Harmonized steam levels to facilitate exchange of steam between plants Use steam at as low temperature as possible Process off gases should be fired at the right location

21 Challenges for Total Site Integration in Stenungsund Utility infrastructure is not designed for site-wide heat integration, e.g. plants specific utility levels and condensate purity restrictions Ownership structure and business strategies of different plants and companies in the complex influence how energy efficiency is prioritized Space availability, plant safety e.g. minimum boiler loads, geographic location of the plants to each other, existing inter-company pipe racks, by-product combustion, existing capacity for co-generation etc. Our research: develop systematic methods for designing total site heat integration networks

22 Current LP steam demand: 25.7 MW 9x 56 Condensor 81,77,57,15, 72,50,31,2,13 49 Condensor 47 flash steam Condensor Potential demand: 40.3 MW Plant F 40.3 MW 20.7 MW E E New site-wide energy network that can save 54 MW 16 Cooler Plant E 65 Rx1 Cooler 25.9 MW HTC column cond Air to PM8 Fluid dryer Rx2 Cooler Air to PM 8 EDC column cond 24 Reb 2.2 MW Air to PM7 9.9 MW 2.6 MW 26.8 MW Fuel: 21 MW E-1701 HPPE16 Plant D E-1608 E-1845 HW2 (97/75 C) Plant C Losses: 2.5 MW Preheat demin CT1701 cond 21.2 MW E-1609 E-1802 Heat savings 54 MW CO 2 savings13.6 % 4 collaborating companies 42 new HXs 2 HW circuits 3 new steam redistribution pipes Fuel redistribution PBP: 3.9 years Air to PM9 3.4 MW E-1890 E-1606Y Current LP steam demand: 2.5 MW Potential Reboiler HTC, 4x Air to spray dryer, demand: Air to dryers x MW 10.5 MW Losses: Plant B Current LP 3 MW steam HW1 demand: (79/55 C) 0.3 MW E-6450, x 2.8 MW Potential demand: 2.8 MW

23 Comparing different options for using excess heat adopting an expanded system boundary CCS ORC Internal heat recovery Electric power grid generation Biorefinery District Heating Primary energy savings can be achieved in the district heating (DH) system Important to compare this with: CHP opportunities in the DH system? Primary energy savings that can be achieved at the process plant site through increased heat recovery The system boundary and time perspective adopted strongly affect the results!

24 The role of process integration research in the Energy in a Circular Economy profile Biomass Resources Advanced separation technologies Thermochemical conversion of biomass CO 2 capture technologies Biochemical conversion of biomass Enabling unit operations and processes Process synthesis and design for resource efficiency Process design and integration Systems analysis Methods and tools for technical, economic and environmental assessment of industrial process concepts

25 Thermochemical recycling of plastics and biomass for production of chemical intermediates at a Swedish chemical complex site Process modelling and simulation Gasification and pyrolysis Synthesis processes Process integration studies Heat integration study for steam generation GHG emission evaluation System definition Emission factors for subprocesses

26 Biomass and recycled material gasification can widen the feedstock base for the chemical industry Raw gas Methane (CH 4 )/Ethylene (C 2 H 4 ) Syngas (H 2 / CO) Carbon dioxide (CO 2 ) Charcoal BTX (Benzene/Toluene/Xylene) 30.6 (21.2/9.4) MW 50.3 (29.5/20.8) MW 20.3 MW extra syngas (max) 15.6 MW 3.7 MW Green intermediates Green hydrogen/methane, or C2-C8 HCs/methane Green carbon dioxide Green BTX Polycyclic aromatic HCs (mainly Naphtalene) 2.3 MW Green Polycyclic aromatic HCs Today Biomass Fuel In the future Biomass/ Recycled material

27 Summary Ongoing Research at Chalmers related to energy efficiency in industry Conceptual design and process integration studies of future process decarbonization solutions for the process industry sector. Investigation of opportunities for and consequences of implementing new energy-related technology in industrial energy systems, in close collaboration with other ECE research groups. Development of methods and models for assessing the impact of decarbonization measures in industrial systems

28 Take-home message Energy efficiency is a key tool for the development of decarbonized industrial processes There is a significant potential for improving energy efficiency in industry The potential improvements are even greater if a systematic approach is adopted Very few potential estimations account for the impact of new technologies, even fewer account for the possible interplay between new technologies and systems The best opportunity for investing in energy efficiency measures is in combination with other strategic investments. This is true for all decarbonization options. Important to consider all options when planning strategic investments.

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