Engineered equipment for pulp and paper mills.
Mills run continuously under high temperatures, extreme pressures, corrosive chemicals, and abrasive slurries. We build the evaporators, exchangers, vessels and tanks that carry that duty.
A long history in mill process equipment.
Harris Thermal has a long history of fabricating heat-transfer and process equipment for the pulp and paper industry. That experience remains valuable for mills maintaining, repairing, or replacing aging equipment as well as for new capital projects.
Core equipment for mill operations.
Evaporation & Heat Recovery
- Black-Liquor EvaporatorsConcentration duty across the recovery cycle.
- Falling-Film & Multi-Effect EquipmentEvaporator bodies and components for the evaporator set.
- CondensersSteam recovery and emissions control duty.
- Shell & Tube Heat ExchangersPulp heating, condensate cooling, bleaching and liquor recovery.
- Replacement BundlesNew bundles built to existing shell and tubesheet geometry.
Process Equipment
- DigestersCustom-built for kraft, sulfite and chemical pulping to ASME Section VIII.
- Pressure VesselsASME-code vessels across mill service.
- Columns & TowersBleaching, washing and chemical absorption duty.
- Cyclones & Washer VesselsGas or fibre separation, pulp washing and slurry handling.
- Mixing Vessels & TanksBlack liquor, white liquor, bleach and stock preparation.
Replacement Equipment
- Replacement Heat ExchangersBuilt to the envelope and nozzles already in the mill.
- Replacement BundlesWhere the shell is sound and the bundle is not.
- Vessels & Evaporator ComponentsRebuilt or replaced to existing interfaces.
- Custom EquipmentBuilt around what the mill already has.
Black liquor evaporation & concentration.
Harris Thermal fabricates evaporator and heat-transfer equipment used in black-liquor concentration and chemical-recovery applications.
The stream gets more viscous, more scaling and more corrosive as it concentrates, so the material and the evaporator configuration follow where in the train the equipment sits. Our article on choosing an industrial evaporator works through that decision.
- Stainless and duplex for corrosion and chloride resistance
- Alloy upgrades where the service requires them
- ASME Section VIII construction
- TEMA-compliant exchangers
Pulp and paper equipment questions.
Can Harris Thermal fabricate replacement equipment for an existing mill?
Yes, and it is a large part of the pulp and paper work. Replacement heat exchangers built to existing envelope and nozzle geometry, replacement tube bundles for sound shells, vessels, and evaporator components built around the interfaces already in the mill. We work from existing drawings, field measurements or reverse-engineered specifications.
What equipment does Harris Thermal fabricate for pulp and paper mills?
Black-liquor evaporators, falling-film and multi-effect evaporator equipment, condensers, shell-and-tube heat exchangers, replacement bundles, digesters, ASME pressure vessels, columns and towers, cyclones, washer vessels, and mixing vessels and tanks.
Can Harris Thermal design replacement or upgraded log vat heaters?
Yes. Log vat heaters are custom-designed and fabricated to the duty and the installation they have to fit. We work from the existing unit, its geometry, the available steam or hot-water supply and the vat conditions, then size and lay out the heater for the required heat load — including reworking the thermal and mechanical design where the original unit was undersized, is fouling faster than it should, or no longer suits the current production rate. Replacements are built to drop into the existing footprint and connections wherever the installation allows. This is the design of the heater itself; the surrounding mill process and controls stay with your team. Harris Thermal has served pulp and paper mills for decades and can work from an old unit with no surviving drawings.
What equipment does Harris Thermal build for black liquor service?
Harris Thermal fabricates evaporator and heat-transfer equipment used in black-liquor concentration and chemical-recovery applications, along with the condensers, exchangers and vessels that run with them. Black liquor is a scaling, corrosive, increasingly viscous stream, so material selection and evaporator configuration follow where in the concentration train the equipment sits.
Ready to upgrade your mill equipment?
From ASME digesters and black liquor evaporators to replacement exchangers and bundles — tell us what your mill needs.