PCCC3 and SaskPower Symposium

Transcription

1 PCCC3 and SaskPower Symposium Regina Canada September 8-11, 2015 Managing Corrosion with Teflon Energy Efficiency, Environmental Protection Plant Availability Proven Technology for Flue Gas Cooler Applications Peter Dittmann, Director Produkmanagement Wallstein Thermal Technology Co., Ltd., Beijing/China Wallstein Ing. GmbH, Recklinghausen, Germany

2 Group History and Growth Strategy - start in turnover in 2014 approximately 30 Mio. Euro VITA - employees mid of in Germany 25 office in China /50 workshop China Wallstein Thermal Equipment Ltd. / Tianjin China Wallstein Saudi Arab Oger Ltd. / KSA Wallstein Thermal Technology Manufacturing Ltd Wallstein Thermal Technology Ltd. / Beijing China Wallstein Manufacturing Co Wallstein Service Co Wallstein Engineering Co.

3 Industries / Products Power Plants Chemicals / Petrochemicals Waste to Energy / Biomass Plants Climate / Environment Heat Recovery System (HRS) Crossflow Flue gas cooling for air-or boiler feed water preheating Leads to efficiency increase Heat Displacement System (HDS) Used for clean gas reheating by flue gas cooling Gas to gas heat exchanger Gas Steam Preheater Reheating of flue gases by the help of steam and/or feed water Preheater/Economizer Air preheating / Flue gas cooling

4 History Beginng at the 1980 s due to clean air act regulations in Germany FGD has been installed. Using rotating GGH for reheating the clean gas. Due to the leakage problems and the negative impact of the enviroment lekage free system are required. Cooler/reheater system liquid coupled with differnt material combination has been taken in operation. Most of them failed due to corrosion problems.

5 Starting Developing Reliable Materials Test installation mainly in slip streams 1980 Wilhelmshaven Germany 1984 Schwandorf Germany 1984 Prunerov Czech Republic 1987 Maribor Slovenia 1992 Schwarze Pumpe East Germany 1995 Lippendorf East Germany Flake lined, vinylester lined different material without good results Material was already long time out of discussion, cleaning needed to be tested because of this critical dust. Material test with C.S. and C.S. lined materials Teflon shows the best results

6 Out of this Test Installations in: Germany Czech Republic Thailand South Korea Todays Installations: Poland Italy Canada China All cooler with Fluoropolymer Tubing based on Teflon

7 Why Fluor Polymers Teflon? This material offers many advantages like: Excellent Corrosion resistance Cleanability due to the non stick surface effect Cost effective High service temperature up to 260 C High flexural fatique strength Stress cracking resistance High Hope stress values

8 Cooling Flue Gases 145 C 50 C 293F 122F SO3, HCL, HF plus H2O forming critical mixture of acids ph values C-130 C 347F - 266F 120 C-85 C 248F -185F Wall temperature below the acid dew point condesation Design aspects: fly ashes acid formation online washing sytem corrosion resistant life time availibility

9 HRS Primary Air and Condensate/District Preheating Increase overall efficiency Coal saving CO2 reduction Water consumption FGD Heat recovery below the acid dew point Corrosion resistant Heat Recovery System with benefits

10 Sulphuric Acid Dewpoint Gas Analysis Influence on the Sulphuric Acid Dew Point Gas Analysis Lignite Hard Coal Oil Sulphuric Acid Dewpoint in Flue Gases N Vol. -% Based on the SO3 content and water dew point in the flue gas O Vol. -% CO Vol. -% H2O Vol. -% Corrosive elements SO2 4, , ,448.0 mg/nm SO mg/nm3 120 HCl mg/nm3 HF mg/nm3 Dust mg/nm SO3 content V ppm Sample: water content in flue gas 8,5%, water dew point 43 C SO3 20 ppm Remark: fly ash will drop the dew point 10

11 Results may be Corrosion started after some month of operation Diffusion and Permeation after half a year operation Nickel Base S.S. Fluor polymer lined 11

12 Results may be Carbon Steel after half a year of operation 12

13 Flue Gas Cooler General Arrangment around FGD Elektrostatic Precipitator 13 Flue Gas Desulphurisation

14 Flue Gas Cooler Installation 14

15 HRS Flue Gas Cooler Installation

16 HRS Flue Gas Cooler Installation

17 HRS Flue Gas Cooler Installation 17

18 HRS Flue Gas Cooler Installation

19 HRS Flue Gas Cooler Installation

20 HRS Flue Gas Cooler Operation Hubertusstraße 44 D Recklinghausen fon +49 (0) fax +49 (0)

21 HRS Flue Gas Cooler Operation 21

22 HRS Flue Gas Cooler Operation 22

23 HRS Flue Gas Cooler Operation Hubertusstraße 44 D Recklinghausen fon +49 (0) fax +49 (0)

24 HRS Cooler in Operation

25 Developing the AlWaFlon Pressure Tube Companies: DuPont in Neomurs Switzerland (actual Chemours ) Fluortubing in Utrecht Netherland and Wallstein Ing. in Recklinghausen Germany jointly developed a solution based on Teflon AlWaFlon Pressure Tubes for the Heat Exchanger application

26 Longterm Pressure Testing Approved by: TÜV for AlWaFlon Pressure Tubes Approval: ASME Section VIII Div.I CC

27 27 AlWaFlon TM is a Thermoplastic Modified Flouropolymer

28 ASME CC 2759 Case XXXX TÜV Approval Use of PTFE Tubing Material for Flue Gas Heat Exchanger Tubes-Section VIII, Division 1 Inquiry: May polytetrafluoroethylene (PTFE) be used for flue gas heat exchanger tubes with water as the tube side fluid and flue gas as the shell side fluid, in Section VIII, Division 1 construction? For the purposes of this Code Case flue gas heat exchangers are used downstream of the boiler and electrostatic precipitator in a power plant. Reply: It is the opinion of the Committee that PTFE may be used for flue gas heat exchanger tubes in Section VIII, Division 1 construction provided the following requirements are met: 1. GENERAL REQUIREMENTS 1.1 The virgin PTFE material shall have no fillers, additives or pigments and shall be in compliance with ASTM D and shall be limited to the polymer with a classification designation of either Type I Grade 4 Class B, or Type I Grade 3 Class D. The PTFE material shall also have a stretching void index of 50 maximum and a thermal instability index of 7 maximum. The PTFE fine powder material shall be certified by the materials manufacturer, and a certificate of analysis shall be furnished to the vessel manufacturer for each batch of finished material from a production reactor.

29 Reference Customers

30 Flue gas cooler with tubes based on Teflon fluorpolymer now in operation since more than 30 years. Thank you for your attention.

31 HRS Primary Air Preheating Heat Recovery System with benefits: Corrosion resistant Increase overall efficiency Coal saving CO2 reduction Water consumption FGD Heat recovery below the acid dew point Wet Stack or Cooling Tower

32 HRS Boiler Feed Water or Distict Heating Heat Recovery System with benefits: Corrosion resistant Increase overall efficiency Coal saving CO2 reduction Water consumption FGD Heat recovery below the acid dew point Feed water and /or District Heating Wet Stack or Cooling Tower 32