COMMUNITY ENE INTEGRATED DEMONSTRAT DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. VOLUME 3A TARLE .OF Description 3.0 Overview 3.1 Steam-ProductionCenter 3.1.1 University Heating Plant 3.1.1.1 Incinerator Renovation 3.1.2 Southeast Steam Plant 3.1.3 Architectural Renovation Demonstration System Capital Costs - 1977 3.1.4 Capital Cost of the Demonstration System Southeast Generating Plant Miscellaneous Retrof =t and Repair 3.1.5 Capital Costs of Demonstration Systenas South- east Generating Plant Removal 3.1.6 Capital Costs of Demnstration Systenas South- east Generating Plant Boiler Retrofit Back to Cbal from Gas - Boiler #3 3.1.7 Capital Costs of Demonstration Systems South- east Generating Plant Boiler Retrofit Back to Coal from Gas - Boiler #4 3.1.8 Capital Cost of the Demonstration Systerns Southeast Generating Plant Piping and Miscel- laneous System Rehabilitation 3.1.9 Capit'al Costs of Dgnonstration Systenas South- east Generating Plant Electrical Rehabilitation 3.2 Pollution.-Control System 3.2.1 Capital Costs of Demonstration System - Baghouses 3.3 Solid Waste Heat Recovery System Description -Page 3.4 Fuel and Ehergy Transport and-Storage 50 3.4.1 Special Train Coal Shipents from Western United States 3.4.2 Ckpital Costs of Fuel and Energy Transport Demon- stration System 3.5 District Heating - Steam 3.5.1 Laundry Heat Recovery Systenas 3.5.2 ~istrictHeating Demnstration System Capital Costs 3.6 District Heating - Hot Water 3.6.1 Distribution Piping 3.6.2 Hot Water Distribution bop . \ 3.6.3 Hot Water Distribution System Calculations 3.6.4 Building System and Service Demand 3.6.5 Hot Water Production - Southeast Steam Plant 3.6.6 Thermal Storage Systems 3.6.7 Construction Costs of Demonstration Hot Water Systenrs 3.7 Combined (hmnmity Service Demands OVERVIEW In 1973, the University of Minnesota set a goal of conversion and retrofit for University Heating Plant whereby coal or lignite would be- cane the prjma.ry fuel by the year 1980. By 1980, that goal--95 percent of the fuel requirement for all Campuses, is to be fulfilled by coal or lignite--will be achieved. Lignite is used at the Crookston Campus. A major part of the conversion and retrofit back to fossil fuels centered at the Minneapolis Campus heating plant. This was due primarily to its size, accounting for 64 percent of the fuel requirements for all University of Minnesota Campuses, and the fact that its reliable capacity was being strained by Campus growth. A report was prepared in 1975, and a subsequent request was pre- sented at the 1976 StateLegislativesession for funds to cover the cost of Phase I of plant expansion and retrofit at the Minneapolis Campus. Funding for retrofit of four existing boilers to bring the plant operation into compliance with EPA and MPCA regulations was appropriated. Our praticipation in ICES will allow continuance of our program and cause some add-on expansion. The add-on work includes additional steam generation and distribution capabilities, electrical generation, a solid waste collection and disposal system with energy recovery, a low energy hot water distribution system for building heating, and thermal storage. Southeast Steam plant will also become the base load plant. Under basic expansion Southeast Steam wuld be a topping plant with initially only one coal fired boiler in operation. The University, with the addition of St. Mary's and Fairview Hospitals, Augsburg College and possibly same snall Ccmnunity add-ons, provides a comrrunity wherein a major portion of steam distribution is already extablished. This provides for the developent of a larger Grid-ICES for relatively low capital expenditure. However, the University steam service demand muld allow demonstration of ICES in itself. The f3mmmity system muld have firm steam requirements of 500,000 lbs/hr during the heavy heating season to a base load demand of approximately 130,000 lbs/hr in the spring and fall (minimum heating - cooling seasons). The generat ion of by-product electricity muld be approximately 50,000,000 kilowatt hours annually. The retro-f itting back of a retired Northern States Power (3rnpany straight condensing generating plant, bringingtm boilers fmgas/oil back to coal, addition of a new high temperature slagging pyrolytic solid waste. gasifier, interconnection of a new 7500 kilowatt back pressure non- condesning or extract ion noncondensing turbine-generat or into the boiler steam output, interconnection of the generator electrical output with the NSP Company utility grid, interconnection of Southeast Steam condensate and steam line with the University of Minnesota's steam distribution, interconnection of a metropolitan hospital and college system ' s existing steam distribution, St. Wy's and Fairview Hospitals and Augsburg College, with University existing steam distribution, regional collection of hospital and health care solid waste, development of a hot water heating and cooling distribution system for a portion of the University's East Bank and all of West Bank, and diurnal and/or seasonal storage of heat comprise the basic changes to the facilities to form a Grid-Connected ICES in the Demonstration Comnunity. The Demonstration System will have an Annual Utilization Factor of approximately 6%, as'shown in the initial ICES proposal. 2 During Phase 11, continued optimization will define the proper choice of a SNC or SAENC turbine. The use of the SAENC turbine depends heavily upon development of a hot water loop and optimization of boiler feedwater temperature. Other in-plant processes, primarily drives for auxiliaries, must be determined. During Phase I, the University optimized both cycles. Calculation for either cycle in this feasibility study show thmto be cmpatible and similar in performance. The generation output (48 x 106 kwh vs. 53 x lo6 kwh) are close and the turbine heat rates (4300 to 4400 B?U/kWh) are approximately the same for either turbine type. If significant loading of the SAEX turbine exhaust can be accomplished by development of hot water heating, this regeneration will increase energy production to 80,000,000 kWh. During Phase I1 significant feasibility must be centered around boiler, feedwater and distribution systems to determine the final chosen turbine cycle. Decisions on systems to finance will be the actual criteria, sincewithout sufficient exhaust loading of the SAENC turbine, a SNC is the better overall choice. The final initial boiler steam conditions on coal, the final distribution system pressure, combination of feed- water and hot water heating into a combined cycle, and the determination of effects of using larger prime movers will all affect by-product powr generation. The determination of plant drive (turbine, electric or combination) will affect the SNC cycle. A gain of approximately 30% in efficiency can be realized by elimination of the low pressure turbine. Development of the hot water distribution system affects by-product powr regeneration of the turbine cycles. The choice of plant drives is critical. For optimum plant efficiency all exhaust from mall turbine I drives must be utilized. There will be requirements for desuperheating at Southeast Steam Plant since this was not covered for the Phase I study. Optimization of this process using low pressure exhaust will further increase plant utilization. Boiler blowdown cycles rmst be optimized by returning blowdown to a flash tank for return to the deaerating heat system. The following diagrams and photos depict the power production sites, the conceptual'process flow diagrams and the cable routing for the electrical grid connection. 30 EXmNSION LlMl 1,000,000GSF BY SUL Wri hEL4- N'i GR\n \CES UNIVERSITY DM- -p FLOW S~,C-HE$./&T\~ TC,K '3EMh\.+ST)i7T)i7ATi.LIN CCW\kAUbk\TY CHECKED DA~ nNI= OF W\Th\ SNC TURB\W= (3PE-T\<- 30 4/1/17 43 , MINNESOTA SOUTHEAST MPUS STEAM PLA *. + I s.,:I- .% kc * C i BY P UNIVERSITY a tk.e.h . .. 1t;:3331 ' CENTRAL PLANT SITES FOR ICES CHECKED OAR DRAIMQ OF 1h J.0. 3/23 MINNESOTA i I UNIVERSITY HEATING PLAWT As stated in Volume 2, Reliable Capacity of the University Heating Plant is 465,000 lb/hr steam when fired on Tennessee coal (12,600 BTU/lb). The major modifications needed on No. 1 boiler and the age of No. 12 boiler (1937) requires that they be prjmarily used for peaking. A 200,000 pound per hour oil fired boiler brings the total plant capacity to 740,000 lb/hr. All of these boilers are 200 PSIG saturated steam units. The plant is arranged for turbine or electric drive with the turbine ex- haust supplying some in-house process and low-pressure (15 PSIG) steam heating and cooling distribution system to same East Bank buildings. The important aspect of this plant is that building expansion by the University alone will exceed the plant capacity in 1980. This condition is further deteriorated because of our cm=trnent to total coal firing capability and the desire to use cheaper and lower sulfur western coals having lower heating values (8600 BW/lb).