Pulp & Paper Mills and Recovery and Power Boilers
Sheppard T. Powell Associates, LLC (STPA) has provided consulting services to a variety of pulp & paper mills – including facilities producing bleached and unbleached pulp, fine paper, consumer products, and newsprint. We have provided consulting services to facilities with varying types of boilers from 400 to 1800 psig – including kraft black liquor recovery boilers, red liquor boilers, and power boilers burning bark, sawdust, gas, oil, and coal. Biomass boiler experience includes both grate-fired and fluidized bed boilers. STPA offers services related to the following topics.
- Boiler water treatment. Some consultants are routinely involved in boiler water treatment reviews at pulp & paper mills. Representatives from STPA have taught the recovery boiler water treatment portion of the TAPPI Kraft Recovery Short Course since 1994.
- Steam purity monitoring and control. STPA has been involved in routine monitoring, upgrading of monitoring systems, and carryover studies.
- Steam/water cycle chemistry, deposition and corrosion. STPA is involved in audits of chemistry sampling, online monitoring systems, laboratory testing, chemistry programs, chemistry limit compliance, troubleshooting, and training.
- Waterside inspections of steam generation equipment and deaerators as part of an assessment of the success of the water treatment program in controlling corrosion and deposition.
- Chemical feed systems for feedwater and boiler water treatment.
- Makeup water treatment equipment selection, system evaluation, troubleshooting, and training.
- Condensate filtration and polishing, specifying, selecting, evaluating and troubleshooting.
- Tube sample selection, deposit weight and composition analyses, determining the need to clean, failure analyses and other metallurgical evaluations.
- Waterwall, generating bank, screen tube, roof tube and floor tube failure investigations for a variety of mechanisms (e.g., overheating, creep, underdeposit corrosion, near drum corrosion, deposit related fireside corrosion, etc.).
- Economizer tube failure investigations related to stress assisted corrosion (SAC) pitting and corrosion fatigue cracking.
- Evaluation of deposition and corrosion in steam water cycles.
- Chemical cleaning planning, specification development, and consulting assistance during chemical cleanings.
- Layup of boilers, including conventional approaches of wet layup and the development of a dry layup system for a recovery boiler at one mill.
- Mill water treatment and corrosion control evaluation. STPA has been a key part of teams evaluating mill water treatment and corrosion control in pulp & paper mills.