Steam & Condensate Systems

 

General

The purpose of this report is to develop a brief analysis of the existing steam and condensate system at the Taylorsville Redwood and South City campuses of Salt Lake Community College. The result of this portion of the analysis will be as follows:

  1. Determine current campus heating loads
  2. Project future campus heating loads
  3. Determine whether or not the main piping leaving the heat plant will be able to handle the future loads
  4. Recommendations regarding the future plant capacities and main line sizing

This report will facilitate in providing a basis for planning, funding, and implementation for future years; however this is not a utility master plan. The report is predicated on the need to provide continued reliable service to existing campus buildings and to determine whether or not the existing infrastructure will be able to support facilities as the campus expands.

Scope of Work

This report analyzes the existing and future needs of the campus Heating Plant and main steam/condensate piping leaving the plant.

The key items undertaken by this study include:

  • Review of existing campus heating demand
  • Review of existing boiler and main piping capacities
  • Utilizing the architectural master plan data (provided by AJC), determine future campus heating requirements
  • Determine whether or not the heating plant in its current state can support the projected campus growth
  • Recommendations

Ancillary equipment associated with the boilers (i.e. boiler feed pumps, dearators, condensate tanks, etc.) will not be included in this report. However, it should be noted that if the plant capacity increases, all ancillary equipment will be required to be analyzed for capacity. Additionally, the steam/condensate distribution system will not be included in this report, but as in the case of the ancillary equipment of the heat plant, distribution piping and associated equipment (i.e. steam traps, expansion joints, anchors, supports, etc.) will be required to be scrutinized as campus capacity is increased.

Conceptual Cost Estimates

Conceptual cost estimates will not be included in this report, but is highly recommended when performing the in depth utility master plan in the future.

Existing Campus Heating Loads

Currently, both the Taylorsville Redwood and South City campuses are served by a central heating system consisting of boilers, ancillary equipment, and distribution system. Central heat plant capacities are determined by summing all of the operational boilers and subtracting out the largest boiler. This new value is called firm capacity. The report will focus on boiler capacities and the main steam piping capacities only (See Table 1-1 and Table 1-2).

Table 1-1: Existing Boiler Capacities – Taylorsville Redwood Campus

Boiler Number Capacity (lb/hr) Install Date Manufacturer
1 17,250 1994 Cleaver Brooks
2 10,350 1972 Cleaver Brooks
3 17,250 2008 Cleaver Brooks
4 13,800 2008 Cleaver Brooks

Note: Main steam line leaving the plant = 8”, operating pressure = 70 psig

Table 1-2: Existing Boiler Capacities – South City Campus

Boiler Number Capacity (lb/hr) Install Date Manufacturer
1 17,250 1993 Seller
2 17,250 1993 Seller
3 5,175 1993 Seller

Note: Main steam line leaving the plant = 12”, operating pressure = 11 psig

Existing campus loads were determined based on gross square footage and a value of 35 btu/h/SF and are as follows:

Table 1-3: Existing Campus Steam Loads Based on Gross Square Footage

Campus Gross Area (SF) Heating Btu/h/SF Total Campus Heating Load (Btu/h) Total Campus Heating Load (lb/hr) Existing Firm Capacity (lb/hr)
Taylorsville Redwood 1,117,914 35 39,126,990 39,127 41,400
South City 346,247 35 12,118,645 12,119 22,425

 

Based on the above data, the current main steam piping sizes of 8” and 12” serving the Taylorsville Redwood and South City Campuses respectively are adequately sized and are able to handle the current loads. However, the 8” steam main serving the Taylorsville Redwood Campus is distributing at peak capacity and would need to be upsized if any additional load were to be introduced to the system.

Future Campus Heating Loads

As in determining the existing loads, the future heating loads were projected by assuming a value of 35 btu/h/SF and utilizing the architectural master plan which identifies the new buildings and layout planned for each campus. The estimated growth is as follows:

Table 1-4: Future Campus Steam Loads Based on Gross Square Footage

Campus Future Gross Area (SF) Heating Btu/h/SF Additional Campus Heating Load (Btu/h) Total Future Campus Heating Load (lb/hr)
Taylorsville Redwood 225,000 35 7,875,000 47,002
South City 200,000 35 7,000,000 19,119

 

Based on the projected growth of the campus, the new heat plant requirements will be the following:

Table 1-5: Future Heat Plant Requirements

Campus Existing Firm Capacity (lb/hr) Future Campus Load (lb/hr) Existing Main Steam Pipe Size (inches) Future Main Steam Pipe Size (inches)
Taylorsville Redwood 41,400 47,002 8” 12”
South City 22,425 19,119 12” 12”

 

Recommendations

Taylorsville Redwood Campus: The Taylorsville Redwood Campus is currently able to provide adequate and reliable steam through its existing distribution system and existing heat plant firm capacity. However, because the existing 8" steam main is at its maximum capacity, any significant additional steam load introduced to the system will require the existing steam main to be upsized. Additionally, Boiler No.2 is approaching the end of its service life. Therefore, any additional planning required to maximize its service or to replace the unit completely is also suggested.
Based on the projected future campus load, the firm capacity of the existing heat plant will need to be increased to match the future load of 47,002 lb/hr and the main steam header will require the existing 8" to be replaced with 12" piping.
South City Campus: The South City Campus is also currently providing adequate and reliable steam to its users. The existing infrastructure has adequate excess capacity to handle the projected future loads as shown in the previous tables. Therefore capacity modifications to its existing steam generating/distribution system is not necessary.
General: In addition to the recommendations stated above, it is also encouraged that the College perform an in depth utility master plan including, but not limited to the following:

  • Steam distribution modeling
  • Analyze existing heat exchanger capacities within building mechanical rooms to more accurately determine building steam requirements
  • Analyze existing distribution system (i.e. pipe supports, guides, expansion joints, anchors, etc.)
  • Verify redundancy of the distribution system (i.e. looping, valving, etc.)
  • Probably costs of construction for infrastructure upgrades