Part 1 of the seven-part series on material selection for chemical process equipment focuses on metals and alloys. Metals and alloys can be selected as materials ranging from larger structural systems to specialty small components for surface finishing process systems. Examples include:

• Structural frameworks, including hoist superstructures, catwalks, and tank supports, to extend beyond base floor elevation and also to suspend equipment from a structure above a process line.
• Material handling equipment, including hoists, shuttles, and carts.
• Process tanks and accessories (e.g., baffles, weirs, equipment mounts, and load saddles).
• Shells and internals of process equipment, including pumps, heat exchangers, and filters.
• Exhaust ventilation collection and air pollution control systems.
• Piping and valving systems for process fluids and process utility fluids.
• Electrical and Instrumentation and Control (I&C) cabinets and electrical conduit.
• Process accessories, including electrodes, mounts, fixtures, flight bars, and sensor probes.
• Grating, platforms, and ladders.

Different metals and alloys provide widely varying chemical resistance. There are also several orders of magnitude in raw metal or alloy cost, ranging from the more common metals and alloys to specialty high performance superalloys to precious metals.  Various metals also range in important physical properties (e.g., density, yield strength, temperature range, formability, stiffness, weldability, electrical conductivity, ferromagnetism, and application-specific durability) that can impact material selection.

ASTM Structural Carbon Steel

These relatively low-cost steels are available in standard grades for structural shapes and plate and for structural pipe and tubing. Chemical resistance is limited for many chemical process applications. Liners and/or coating/paint systems are required for most applications of steel components in process plants for chemical exposure applications. Proper surface preparation using abrasive blasting and/or chemical pretreatments of steel components is critical with for successful application of liners and/or coating/paint systems. Primary applications for coating systems include superstructures, tanks support systems, and platforms. Primary applications for liners are process tanks.

Stainless Steel (SS) Alloys

Stainless steels (e.g., 304, 304L, 316, & 316L) are common in surface finishing applications. The alloy mix for 316SS alloys (~16% chromium (Cr), ~10% nickel (Ni), ~2% molybdenum (Mo) provides for superior chemical resistance, including many solutions containing chlorides and some acids, over 304SS alloys (~18% Cr, 8% Ni). However, there are applications where 304SS provides superior chemical resistance to 316SS. 304LSS and 316LSS are lower carbon alloys that are better for welding. Stainless steel alloys provide superior chemical resistance over carbon steel for a broad range of applications. Steel alloy prices vary with market conditions and alloy metal price variances. Relative prices also vary with form and quantity purchased. 316LSS plate is almost 30% higher in price* over 304LSS plate, and 304SS plate is roughly four times the price* of A36 grade carbon steel plate.

High Nickel Content Alloys

These higher cost alloys, such as Hastelloy C, provide superior corrosion resistance beyond SS alloys for some applications. However, some SS alloys provide superior corrosion resistance for some applications over high nickel alloys (e.g. – some phosphoric acid solutions). The nickel content of Hastelloy C276 is typically up to 56%. Hastelloy C276 is more than five times the price* of 316LSS and has approximately 10% higher density. The yield strength of C276 is similar to titanium.

Titanium (Ti) and Alloys

These metals and alloys range significantly in cost and provide superior chemical resistance for many applications. Titanium is lower density than 316LSS  (~56%) and higher yield strength (~160%). Grade 2 (commercially pure) Ti has good weldability, strength, ductility, and formability and is the most common bar and sheet form for chemical process applications including tanks. While Grade 2 Ti is over four times the price* of 316LSS on a per weight basis, it can be only an approximate 50% price* premium over 316LSS for structural applications where Ti higher strength and lower weight factor into the equipment (e.g., tanks). Grade 5 Ti (aircraft grade) is the most common Ti alloy and accounts for ~50% of Titanium global use. Grade 7 Ti is similar in properties to Grade 2 but has interstitial palladium (Pd), making it the most corrosion resistant of all Ti alloys. Grade 7 Ti is almost five times the material price* of Grade 2 Ti. Some nitric acid applications are one example where stainless steels (304LSS in particular) provide superior corrosion resistance over pure Ti. Titanium provides superior chemical resistance for some chromic acid solutions, compared to 316LSS and Alloy 276.

Copper (Cu) and Alloys

In surface finishing, copper bussing (typically C11000 Electronic Tough Pitch – 99.9% Cu) is widely used above tanks for electrified processes. Copper is typically not recommended as a primary material for a range of acid and caustic solutions. A combination of good design for bussing routing, ventilation design, design to minimize dripping and splashing on bussing, and good process maintenance and housekeeping practices are needed to minimize copper bussing corrosion. In some cases, copper is plated or coated to control corrosion.

Other Metals

Many other metals and alloys are important for select process chemistry applications in surface finishing. Precious metals, such as gold (Au), palladium (Pd), and platinum (Pt), provide some of the highest levels of chemical resistance and are important metals for some process chemistry applications. These are extremely high in price and used only when essential. For some specialized applications, other noble metals, such as rhodium (Rh), ruthenium (Ru), rhenium (Re), and iridium (Ir), are used in pure form or in alloys (e.g., Ru is alloyed with Pt or Pd to increase wear resistance) for their differing physical and chemical resistance properties. Iridium is generally the most corrosion-resistant metal. Some other metals and applications are as follows:

• Tantalum (Ta), Zirconium (Zr), and Niobium (Nb) are significantly higher cost than titanium and provide superior chemical resistance in select applications (e.g., heat exchanger internal metals for aggressive process chemistries).
• A range of electrode metals are used for chemical processes application. In some cases, soluble metal anodes are used to make up solution chemistries. In other cases, metals are selected to provide more stable, inert electrodes. Electrode metals and alloys include copper, gold, iron, nickel, lead, platinum, silver, tin, titanium, and zinc and metal alloys, such as brass and tin-nickel.
• Life-cycle, cost-effective, insoluble anodes include more noble metal and metal oxide coatings comprised of Ir, Pt, Rh, Ru, and/or Ta over a lower-cost base metal (e.g., titanium).

Various metals and alloys are suitable for a wide range of surface finishing chemical process equipment applications. The process chemistry application range of lower cost metals can be extended with liners and with coating and paint systems (see Part 4). A diversity of plastics (see Part 2) and other materials, such as fiberglass (see Part 3), provide alternatives to metals for many surface finishing process chemistry applications.  Life-cycle costs should be carefully evaluated for different material options for chemical process equipment.

Next week, watch for Part 2: Material Selection for Chemical Process Equipment – Plastics. Part 2 provides information on PVC and CPVC, PE (various densities), PP, PVDF, PTFE, and other plastics. 

*- Early 2019 pricing. Metal and alloy prices vary with market conditions (e.g. – between late 2005 and late 2008 Ni metal price increased by more than 330% and then dropped to less than 20% of peak price.)

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Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

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Is your surface finishing line well-designed? Material selection for chemical process equipment is critical to the design and implementation of high-quality and cost-effective surface finishing systems. The goal of this seven-part series is to discuss some basic information to help identify and plan for the complex array of design and life cycle project considerations for material selection for process systems. This series will lay out the major material groupings; discuss the factors that impact material selection in practical application; and, finally, tie everything together by exploring the economic and operational benefits of proper material selection. To kickoff, the following is an overview of the topic of material selection for chemical process equipment.

Overview

Whether planning new or renovated wet process systems, material selection for chemical process equipment should be carefully evaluated and documented for all process systems that will or could be exposed to the planned process chemistries. Critical systems to consider include, but not limited to:

• Primary and ancillary process systems/equipment, and all subcomponents, that store, transfer, or process the wet process fluids, including fluid tanks and attachments, pumps, piping/valving systems, filters, heat exchangers, treatment vessels and reactors, and sumps.
• Hoists, cranes, and transport systems.
• Exhaust ventilation collection and air pollution control systems.
• Exteriors of process systems/equipment, and all subcomponents, as well as all related/other systems and structures (e.g. – grating, platforms, ladders) that will be or potentially could be exposed to spills, splashes, or vapors from the process fluids and associated process chemistries.
• Electrodes, eductors, sensors, fixtures, and other devices immersed in process solutions.
• Instrumentation and control systems, including panel enclosures.
• Conduit and enclosures for electrical power and distribution systems.
• Spill containment systems and wastewater treatment systems.

For each application, a full material selection must include all components, including wetted and non-wetted surfaces, motors, gaskets and seals, miscellaneous mechanical, electrical, and I&C devices and parts/components. Material selection for chemical process equipment impacts systems designed and selected across process, mechanical, electrical, I&C, civil, and architectural disciplines.

About Material Selection

Complete material selection for even a single piece of equipment, like a process solution pump, can include a combination of several materials needed to provide long life for all subcomponents. Commercial material variations in purities, compositions, densities, and other properties are available for different applications and can provide varying chemical resistance and different physical properties. Even though some materials have generally superior chemical resistance across a range of chemistries, there are specific chemistries and applications where a typically superior, higher cost material will underperform a lower cost material with typically lower resistance to chemical attack.  Chemical resistance can be highly application-specific and must be carefully evaluated.

Next week, watch for Part 1: Material Selection for Chemical Process Equipment – Metals. Part 1 provides information on steel and stainless steels (e.g. 304LSS & 316SS), copper, zinc, and nickel, high content nickel alloys like Hastelloy C-type, high performance metals like titanium, tantalum and zirconium, and selected uses of precious metals like silver, gold, and platinum.

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Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

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ITI’s GDPR Privacy Policy

If you’ve received this email, you opted in to receive the Integrated Technologies, Inc. email newsletter at some point in the past.  We only store your email address and name with the sole purpose of sending you our email newsletter on a quarterly basis.

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Creating Roadmaps for Successful Transformation

21st Century surface finishing manufacturers face challenges to be profitable while improving quality and efficiency. Other challenges include responding to changing production and health/safety/environmental requirements. There are substantial opportunities for process improvement to meet and rise above these challenges – success depends on seeing the opportunities and moving forward with successful projects for renovating or implementing new process and operations systems. Advanced planning enhances visualizing opportunities and creates roadmaps for successful projects.

Advanced planning provides strong benefits at relatively low investment for almost any surface finishing project. Advanced planning improves project vision and encourages strategic thinking. Advanced planning can range from focused and fast-track conceptual/strategic planning to comprehensive master planning. Advanced planning is tailored to specific project needs and opportunities, providing a range of ongoing benefits, including:

• Avoid costly rework
• Discover and plan synergistic approaches
• Provide a framework for more efficient communication and decision-making
• Provide a framework for more efficient design and implementation
• Prepare for uncertainties and changes

Plan to Plan

Advanced planning starts with recognizing its value for a surface finishing project or series of projects and allocating appropriate time and resources. Key elements to consider for the advanced planning process include:

• Background/orientation – What is the current and desired surface finishing situation? What are the goals and constraints? What information and resources are available?
• Assessment/analysis – Consider the current situation and potential approaches to achieve the desired situation. Consider interrelated elements and influences/impacts.
• Approaches – Strategize solution outcomes to achieve desired results and alternate solutions that may provide additional value through encompassing other opportunities and benefits.
• Conceptualization/Visualization – Develop concepts, description and examples (graphics, models, pictures and/or visit facilities) that enhance visualization of alternate solutions.
• Decision Framework – Define decisions to be made and a decision methodology that will keep the project moving forward with maximum efficiency.
• Change Management Strategy – Define potential changes and establish approaches for responding to and managing/minimizing impact to the overall project.
• Documentation – Advanced planning must be well documented to provide for an easy and useful reference to guide future decision-making.
• Successful process troubleshooting involves planning for and commitment of adequate resources – including people, time, and access to processes/information and funding.

A manufacturer’s decision to seek guidance early from surface finishing advanced planning experts (planning to plan) provides an opportunity to achieve significant benefits and cost savings that would otherwise be missed or will cost significantly more to achieve later.

Strong Payback for Advanced Planning

Expert advanced planning achieves strong short-term paybacks and sets the stage for enhanced life cycle project benefits and cost savings. Advanced planning can reduce the design cost for surface finishing projects by anticipating and avoiding costly changes and by providing a basis for a more efficient design process (see Figure 1, line A compared to B). Advanced planning can reduce implementation costs for surface finishing projects by anticipating and avoiding costly changes and by providing a basis for more efficient construction/ implementation (see Figure 1, line A compared to C or D). Advanced planning typically pays for itself during the design phase. Construction and life cycle O&M cost savings for advanced planning are typically orders-of magnitude greater than the initial advanced planning investment.

Figure 1

Capital cost range and scenarios for surface finishing project

Figure 2

Capital and O&M costs for new surface finishing lines

Figure 3

Capital and O&M costs for complex surface finishing facility renovation

Figure 2 shows a comparison of capital and combined capital plus five year operating and maintenance (O&M) costs for three project scenarios for new surface finishing lines and related process systems: design/implementation without advanced planning (A), design/implementation with advanced planning (B) (allowing for design, implementation and O&M efficiencies for a project scope similar to A), and design/implementation with advanced planning and additional capital expenditures to achieve additional O&M efficiency identified in advanced planning (C). One of the biggest paybacks with advanced planning utilizing surface finishing experts is to foresee and have the opportunity to implement changes that would be cost effective even as retrofits after a project is complete. These changes may be implemented at no or little incremental cost if integrated into the original project.

Benefits of Expert Surface Finishing Support

Advanced planning sets the stage for successful surface finishing design, implementation, operations and maintenance, and also allows preparation for efficiently managing change and uncertainty. Surface finishing advanced planning experts enhance the overall effectiveness of projects for new/renovated processes and systems/practices by augmenting client resources, providing:

● Expertise – The combination of broad range and depth of expertise with surface finishing processes (setup areas, racking and fixturing, hoists, process mechanical, ventilation and air pollution control systems, building interfaces, water and wastewater treatment, automation and information systems, heating and cooling systems, agitation and pumping systems, rectifiers, safety systems, process solution maintenance and control, workflow, etc.) enhances integrated advanced planning that considers interrelated systems. Expert surface finishing process input can provide essential insight for developing both short term fixes and systematically working through more complex issues.

● Perspective – Expert perspective based on successes and failures/shortcomings from a large number of diverse surface finishing manufacturing facilities provides compelling input early in the project to make decisions resulting in some significant cost-saving and/or project enhancing changes. These changes would not otherwise happen or would be realized much later when costs for making changes are significantly higher. Knowledge of previous similar process improvement situations and results, of best management practices, and of the full range of relevant process steps and issues can help to avoid rounds of costly trial and error problem-solving and can lead to better overall process improvement solutions that are more robust, flexible and cost-effective.

● Visualization – Significant past experience with mapping, schematics, diagrams and even process models and early 3-D visuals provides a strong basis to visualize new or renovated facilities and processes. Visualization helps with anticipating issues and opportunities and overall integrated systems. Visuals are key to providing clients with better understanding of alternatives and opportunities earlier in projects. This leads to better decision-making.

● Tools/Methods – Significant experience with advanced planning tools and methods, decision processes and outcomes, and quantities and costs, facilitates and enhances the effectiveness of this critical early project phase.

● Standard and Custom Solutions – Client needs are met and exceeded at minimal cost and risk when customized solutions are developed from proven approaches based on expert consideration of site-specific, application-specific factors.

Surface Finishing Master Planning

Surface finishing master planning is advanced planning dealing with integration of relatively complex series of projects, renovations or new surface finishing systems that are large and diverse and/or have significant interface and/or phasing issues. The master plan helps ensure that projects are done right the first time and that future projects follow a logical and systematic development plan. The master plan is a tool for management decision support regarding surface finishing and related systems and facilities and resources supporting interrelated projects that work well together to most efficiently and effectively achieve desired outcomes. Master planning provides a comprehensive approach to decision-making and to change management. The benefits and cost paybacks for master planning increase dramatically as the complexity of a project or interrelated projects increases. Figure 3 provides the same comparison for planning/design/implementation as Figure 2, but showing even stronger initial and longer term cost savings for a complex, multi-phased surface finishing renovation project.

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Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries. 

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ITI’s GDPR Privacy Policy

If you’ve received this email, you opted in to receive the Integrated Technologies, Inc. email newsletter at some point in the past.  We only store your email address and name with the sole purpose of sending you our email newsletter on a quarterly basis.

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Manufacturing Asset Assessment & Planning (MA2P) is a comprehensive process and strategy to optimize the life cycle costs and improve the reliability of manufacturing assets. MA2P is a unique tool developed by Integrated Technologies Inc. to assess the physical condition, operational efficiency, impact of failure, and relative risk of failure for process equipment, physical plant, and plant systems. Life cycle costs and risk can be managed with effective planning. MA2P deliverables include a quantitative assessment of condition and risk and recommendations to reduce operational life cycle costs and mitigate risk. Investments in MA2P can extend the life of manufacturing assets, reduce the risk of business interruption and EH&S system failures, and dramatically improve operational efficiency.

A detailed audit report is generated for the wet process lines and wastewater treatment systems (as applicable). Each piece of equipment and the system is identified with a written description of the defect and rated. The risk table above is utilized to categorize the various components and system defects to establish a level of risk or importance based on the ratings and level of impact. The final report summary provides specific recommendations for corrective action and associated estimated costs.

Typical Report Segment:

Problem:
Tank T-400 Deoxidier liner is constructed of 316L stainless steel material and is not compatible with the mixed acid bath chemistry which includes HF. The liner (which replaced an earlier FRP liner) is expected to fail prematurely.

Level of Importance: Extremely High
Condition Rating: 3
Application Rating: 0
Impact Rating: I
Areas of Impact: P, S, M. H

Recommendation:
A flexible PVC drop-in liner (1/8″ thick) should be installed over the existing stanless steel liner. The saddle clips to hold the flight bar will require redesign. The drop shields and channel moats will require redesign and are coverd as a separate problem. A leak detector shoudl be installed between the PVC and stainless steel liners. A spare liner can be purchased for use in this tank or others for emergency for cost of approximately $13,000. Note: A more rebust solution would be to install a Koroseal liner but this would increase cost.

Estimated Cost (ROM): $35,000 (includes installation of drop-in liner, shipping and leak detection plus rental of temporary storage for five days.

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Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries.

PROCESS VENTILATION OVERVIEW

Process ventilation is required in surface finishing facilities to comply with OSHA and environmental regulations to protect worker health and safety, and prevent corrosive and moisture laden vapors from accumulating in the shop atmosphere. Process ventilation is also required to protect adjacent process solutions from airborne contaminants and protect real assets (building systems and process equipment) from corrosive mists and vapors. Process ventilation can result in large energy consumption due to the need to heat, cool, filter, and/or dehumidify makeup air that is removed by the ventilation system and discharged outside the building. Efficient process ventilation design practices will reduce capital equipment costs, energy consumption, and overall operating costs.

Inefficient and oversized process ventilation systems increase the size and operating cost of the following:

• Process tank heating equipment
• Ventilation equipment and pollution control equipment
• Makeup air units (MAU’s)

MAUs are used to balance building air systems by replacing the air removed by the exhaust ventilation system. Effective integration of makeup air and ventilation system design is critical to the performance of the ventilation system.

The optimum time to improve the efficiency, effectiveness and operating costs of ventilation systems is during the initial design of the surface finishing system and facility; however, existing systems can almost always be effectively renovated and improved.

EXISTING PROCESS VENTILATION SYSTEM ASSESSMENT

Existing ventilation systems may be inadequate to properly protect workers or assets due to the following:

• Improper ventilation system design (capture efficiency, sizing, materials of construction, structural, and/or condensate drainage)
• Improper system balancing
• Design criteria changes:
  • Lower personal exposure limits (PEL) for specific chemistries
  • New chemistries have replaced the original chemistry in process tanks
• Parts, racks, and fixtures that interfere with the ventilation system
• Modifications to ventilation systems by the addition of new processes
• Lack of proper maintenance
• Inadequate makeup air supply

We recommend that existing surface finishing facilities have experienced technical staff or consultants review potential exposure issues and ventilation designs. The following questions should be answered to characterize the effectiveness of existing facility ventilation systems:

• What are the principal hazards (See Tables 1.0 and 2.0)?
• What hazards require stricter control?
• Are there any hazards that require periodic review for regulatory compliance?
• Has the ventilation system been designed to adequately mitigate the identified hazards?
• Has the ventilation system been tested and validated for proper air flow?
• Are odors present?
• Is mist or steam observed escaping from process tanks?
• Is there evidence of corrosion of process equipment or the building due to air emissions?
• Is there evidence of staining near process tanks from condensed vapors?

Table 1.0 Determination of ACGIH Hazard Potential Standard Based Upon Hygienic Standards 
(See ACGIH Ventilation Handbook – Appendix A)

Hazard Potential	Gas & Vapor (ppm)	Mist (mg/m3)	Flash Point °F
A	0-10	0-0.1	–
B	11-100	0.11-1.0	<100
C	101-500	1.1-10	100-200
D	>500	>10	>200

Table 2.0 Determination of ACGIH Rate of Gas, Vapor or Mist Evolution Standard

Rate	Liquid  Temp °F	Degrees Below  Boiling Point °F	Relative Evaporation Rate* (Hours for 100% Evaporation)	Gassing**
1	>200	0-20	Fast (0-3)	High
2	150-200	21-50	Medium (3-12)	Medium
3	94-149	51-100	Slow (12-50)	Low
4	<94	>100	Nil (>50)	Nil

*Dry Time Relation (See ACGIH Ventilation Handbook – Appendix B) <5 Fast; 5-15 Medium; 15-75 Slow; >75 Nil

**Rate of gassing depends upon rate chemical or electrochemical activity, which is dependent upon the material treated and solution chemistry. This activity tends to increase with (1) amount of work in the tank, (2) concentration of solution in the tank, (3) temperature of solution in the tank, (4) current density applied to work in the tank in electrochemical tanks.

Some materials commonly found in surface finishing facilities are targeted for more stringent control. Periodic reviews of processes, with constituents such as chrome, nickel, and cobalt, are recommended.  Proper ventilation of these processes is essential; robust design approaches and/or increased ventilation rates may be required.

Some process solutions, such as chromic-sulfuric etches, aluminum etches and bright dips, and hard chromium plating solutions are notoriously difficult to effectively ventilate due to vigorous generation of mists and may warrant added devices such as enclosures, shields, and/or tank covers to isolate process tanks from workers and adjacent processes.

Observation of mist escaping or staining near the process tanks may indicate that the ventilation system is not performing adequately. These signs may indicate a worker exposure problem that testing can quantify. These same signs typically mean that the facility building and process equipment will require more frequent maintenance and repair, as corrosive vapors or mists, that are not effectively captured, may attack susceptible components of the building and equipment.

VENTILATION SYSTEM DESIGN REVIEW

A highly effective ventilation system contains many elements. A systematic review looks at each of the elements to ensure effective operation and should include the following:

• Process Conditions
  • Solution chemistry & operating parameters (concentration, temperature, and agitation)
  • Freeboard
  • Parts, racks & fixtures
  • Materials of construction (chemistry and temperature)
• Ventilation hoods, push air, covers, ducts, drains, structure, fans, blowers, and scrubbers, etc.
• Facility Conditions
  • Makeup air delivery
  • Air balance
  • Open doors & windows
  • Cross current air-flow
  • Airborne contaminants from adjacent manufacturing processes (dust, oil mist, etc.)
• Equipment and facility condition and maintenance
• Personnel and material traffic patterns

Review of the basic design analysis is important in order to determine if the system is capable of operating at a level sufficient to protect workers and to identify where changes are needed based upon the identified hazards. Design review includes the following:

• Process specific hazards
• Checking ventilation requirements based on hazard rating and the physical nature of the process (i.e. temperature, agitation chemical activity, tank size)
• Checking ventilation design factors based on ventilation rates and a number of ventilation design parameters, including:
  • Hood slot velocity
  • Hood slot size
  • Hood plenum depth
  • Duct velocity
  • Duct sizing
  • Push air rates
  • Push air manifold design
  • Cross currents in facility
  • Condensate drainage in hoods and ducts

ENERGY MANAGEMENT

Varying ventilation rates, as a function of operating conditions, enhances energy efficiency. Process solution temperature and agitation can be controlled differently under active, standby, and inactive operating conditions which impact solution air hazard ratings and required ventilation rates. Automated covers, ventilation hood duct dampers, and automated push air manifolds can be integrated with process tanks to reduce ventilation rates based upon cover position (open or closed). Variable ventilation rate control may require ventilation and makeup air system fans to be equipped with variable frequency drives (VFD’s) to meet process ventilation demands and proper building pressure requirements.

Conducting a review and assessment of the ventilation system operation is paramount to improve system performance and reliability.  A typical review would address the following areas:

• Start-up procedures
• Operating procedures
• Work load and production schedules
• Process demand
• Shut-down procedures
• Redundancy or back-ups
• Periodic testing
• Preventive maintenance program

Comparing operation to design is important to assess process-specific functionality and to identify gap areas where operation and design do not match. A key part of the assessment is to examine the preventive maintenance program and look at data logging, operation outside the allowable limits, and down-time issues.
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Integrated Technologies, Inc. is an industry-leading engineering, design, and consulting solutions firm based in Burlington, VT. We offer project planning and development, full-service engineering and design, project and construction management, and services during construction to the surfacing finishing and industrial manufacturing industries.