BOWEN UNIT 3 FLUE GAS DESULFURIZATION SYSTEM€¦ · gas exits the sparger tubes below the slurry...

BWN-3-02603.301 Rev 1 Process Description Plant Bowen

Date Printed 3/7/2011 Page 1 of 54

Approved Plant Review Board Approved Operations Manager Approved Plant Manager Date:

BOWEN UNIT 3 FLUE GAS DESULFURIZATION SYSTEM

JBR VESSEL SYSTEM PROCESS DESCRIPTION Document No. 2603.301

NOTE: If you are working with a printed copy of this document, it is NOT a Controlled Copy.

Please be sure to check online for the most recent revision.

BWN-03-02603.301 Rev 1

Confidential Information Page 2 of 54

T able of C ontents

2603.301 PROCESS DESCRIPTION 3

2603.301.1 SAFETY CONSIDERATIONS 3

2603.301.2 PROCESS FLOW DESCRIPTION 4 2603.301.3 PROCESS DESCRIPTION 5

2603.301.3.1 INTRODUCTION 5

2603.301.3.2 SYSTEM COMPONENTS 13

2603.301.3.2.1 JET BUBBLING REACTOR (JBR) VESSEL (SK-RX-5001) 14

2603.301.3.2.2 JBR SPARGER TUBES 18 2603.301.3.2.3 JBR DECK WASH SYSTEM 21 2603.301.3.2.4 JBR GAS RISER AND WALL WASH SYSTEM

24 2603.301.3.2.5 JBR MIST ELIMINATOR 28 2603.301.3.2.6 LOWER AND UPPER MIST ELIMINATOR

WASH SYSTEM 33

2603.301.3.3 SUMMARIZED JBR LEVEL CONTROL 36 2603.301.3.4 DETAILED JBR LEVEL CONTROL 36 2603.301.3.5 SUMMARIZED JBR PH CONTROL 39 2603.301.3.6 DETAILED JBR PH CONTROL 39 2603.301.3.7 SUMMARIZED SO2 CONTROL 40 2603.301.3.8 DETAILED SO2 CONTROL 40 2603.301.3.9 SUMMARIZED JBR DENSITY CONTROL 41 2603.301.3.10 DETAILED JBR DENSITY CONTROL 41 2603.301.3.11 SUMMARIZED JBR WASH CONTROL 42 2603.301.3.12 DETAILED JBR WASH CONTROL 42

2603.301.4 PROCESS FLOW DESCRIPTION 43 2603.301.5 DRAWING REFERENCES 49

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2603.301 P R OC E S S DE S C R IP TION 2603.301.1 S afety C ons iderations

1. All Operating Companies Safety and Health Manuals shall be followed at all times.

2. The Southern Company Generation Clearance Procedure shall be followed at all times.

3. A thorough Job Safety Briefing (JSB) shall be completed before beginning work.

4. Employees should always use the proper (Personal Protection Equipment) PPE for the task they are performing.

5. Personnel must observe standard safety precautions when working around or with pressurized piping systems.

6. When using the JBR Vessel System hose stations, personnel must wear protective eyewear at all times. The aim and discharge of pressurized water toward solid surfaces may dislodge dirt or other foreign material into the surrounding environment at a high rate of velocity.

7. Personnel must be aware that many components of this system are maintained in an automatic mode of operation. The equipment may start at any time without warning.

8. Personnel should remain clear of all rotating machinery, whether operating or in standby, at all times during unit operation.

9. Rotating machinery must never be placed in service without the appropriate equipment guards in place.

10. No attempt should be made to bypass or eliminate equipment safety interlocks. Doing so could result in equipment damage and possible injury to plant personnel.

11. Follow proper Confined Space Entry Procedures when entering confined spaces.

12. When employees are performing work on or associated with exposed lines or equipment energized at 50 volts or more, persons trained in First Aid including Cardiopulmonary Resuscitation (CPR), shall be available within 4 minutes per OSHA 1910.269 requirements.

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2603.301.2 P roc es s F low Des cription The following subsections contain function and description of major components within this system. This procedure contains summarized and detailed controls descriptions of this system. This procedure contains a step by step process flow description of this system.

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2603.301.3 P roc es s Des c ription 2603.301.3.1 Introduc tion

The JBR Vessel System is the primary component in the Flue Gas Desulfurization System (FGD) where Sulfur Dioxide (SO2) is removed from the flue gas by a chemical process. The system is based on the CT-121 Thoroughbred Jet Bubbling Reactor (JBR) technology of Chiyoda Corporation of Yokohama, Japan. The basic process involves bubbling incoming flue gas through limestone slurry, allowing a chemical reaction to remove flue gas Sulfur Dioxide (SO2) and produce a usable gypsum byproduct, then discharging the treated flue gas into the atmosphere. The CT-121 process can be described in simple terms as the bubbling of flue gas through reactant slurry. This is accomplished with a patented Jet Bubbling Reactor (JBR) which sparges the flue gas into the absorbent slurry. The flue gas handling system delivers flue gas to the gas cooling duct where the gas stream is quenched through the prequench water and gas cooling slurry sprays. Water from the make-up water subsystem is sprayed into the incoming flue gas stream. Gas cooling pumps circulate slurry from the JBR reservoir to gas cooling duct sprays. The untreated but quenched, flue gas leaves the gas cooling duct and enters the vessel via an enclosed plenum chamber above a sparger deck.

Expansion Joint

Gas Cooling Duct

Expansion Joint

Outlet Duct

JBR Vessel

FLOW

Expansion Joint

Expansion

Joint

FLOW

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2603.301.3.1 Introduc tion

The flue gas flow is distributed around the plenum. The flue gas contacts the slurry contained in the reservoir section of the JBR vessel through sparger tubes in the floor of the deck. The deck is continuously washed with slurry from the gas cooling pumps. The flue gas exits the sparger tubes below the slurry surface. After bubbling through the slurry, the flue gas flows upward through a central gas riser and the cleaned flue gas passes out of the JBR through a mist eliminator to flue gas handling system for transport to the wet stack. The overall SO2 reducing reaction is depicted in the following equation:

SO2 + CaCO3 + ½ O2 + 2H2O → CaSO4•2H2O + CO2 The slurry in the JBR reservoir is divided into two zones:

• The jet bubbling zone or froth layer

• The reaction zone This concept is an important design feature because it allows the five primary chemical processes involved in SO2 removal and gypsum production to occur simultaneously within the JBR vessel:

• Absorption of SO2

• Oxidation of acid sulfites to acid sulfates

• Limestone dissolution

• Neutralization of acid sulfates to form gypsum

• Production and growth of gypsum crystals The jet bubbling zone is a layer of froth composed of bubbles that continually form and collapse. This froth layer is formed when the untreated flue gas enters the JBR and is accelerated as it passes down through the multiple sparger pipes and bubbles out beneath the surface of the slurry.

Illustration of JBR Processes

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Removal is further enhanced by the successive rapid collapse and formation of bubbles in the jet bubbling zone. This action continually regenerates fresh interfacial area, transports reaction products away from the jet bubbling zone into the reaction zone, and brings fresh reactants into contact with the flue gas. The surface renewal maintains a high mass transfer driving force for SO2 absorption and a large solid to liquid contact area for collection of other acid gases and flyash.

Removal efficiency is a function of the depth of submergence of the sparger tubes and of the pH of the slurry. Since sparger position is fixed, this depth is varied by controlling the liquid level in the JBR.

The submergence depth varies depending on inlet SO2 concentration, operating pH, and SO2 removal requirements. JBR level is maintained to ensure a minimum of 6” submergence which has been proven to maintain opacity emissions below Title V requirements.

The pH is controlled by the addition of limestone slurry from the limestone handling subsystem. The JBR is designed to operate between pH values of 4.0 and 5.5. This relatively low pH promotes rapid and complete limestone dissolution.

The bulk of the slurry in the JBR resides in the reaction zone just below the froth zone. The JBR is designed to provide gypsum crystal residence time to complete the chemical reaction initiated in the froth zone. Sufficient time is also allowed for:

• Dissolution of the oxygen from the oxidizing air injected into the slurry at the bottom of the reaction zone.

• Oxidation of dissolved sulfite to sulfate.

• Limestone dissolution.

• Reaction of limestone with acid sulfate to form gypsum and release CO2.

• Gypsum crystal production and growth.

An excess of air is injected into the JBR to rapidly oxidize the absorbed SO2 to sulfate. This air is provided by oxidation air blowers and associated piping, valves, instrumentation and other equipment. The oxidation air is saturated with make-up water within the JBR oxidation air piping. The rapid oxidation created by the low pH environment and intensive oxidation air injection is a key to the successful operation of the JBR. Thus, the slurry in the JBR is composed essentially of gypsum solids. This slurry concentration is maintained at a setpoint of 20% solids by drawing off the appropriate amount of gypsum slurry via the gypsum draw-off pumps to the gypsum Dewatering facility.

The JBR is designed with four large diameter, low speed mixers, which, in conjunction with the supplementary agitation provided by both the flue gas sparging and the oxidation air injection provide all the circulation required to transport reagent and products between the froth zone (site of gas liquid contact) and the reaction zone.

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The jet bubbling zone, or froth layer, provides the gas liquid interfacial contact area in the JBR where SO2 in the flue gas dissolves in the liquid film on the surface of the bubbles. The bubbles provide a vast interfacial surface area. Fly ash in the flue gas also contacts the liquid film and is captured. Other acid gases such as hydrochloric acid (HCl) and hydrofluoric acid (HF) are also absorbed at levels exceeding 97%. Control of JBR slurry pH is the key factor in the operation of the JBR, since the SO2 removal efficiency is directly affected by slurry pH. The low pH environment in the JBR slurry promotes SO2 absorption, rapid and complete limestone dissolution, accelerated oxidation of acid sulfites to acid sulfates for gypsum production, and minimizes scaling. At a pH below 5.2, limestone dissolves rapidly and completely resulting in almost no solid phase calcium carbonate providing for high purity gypsum. The DCS monitors JBR pH, unit load, and limestone slurry density and flow to adjust the JBR limestone flow control valve to maintain a JBR slurry pH of 5.2 during normal operations. Unit load is monitored to anticipate JBR slurry pH changes caused by the changes in absorbed SO2 during load transients. During start-up, the DCS minimizes limestone flow until the JBR slurry pH falls close to the setpoint which allow for system stabilization. Control of JBR liquid level is another critical factor in the operation of the JBR, since the SO2 removal efficiency is directly affected by JBR liquid level. The flue gas contact time with the slurry increases as the slurry level above the sparger tubes is increased. The more contact time the higher the SO2 removal efficiency. Since specific JBR levels have a corresponding SO2 removal efficiency, the JBR level associated with the desired SO2 removal efficiency selected by the Operator is used as the level set point. In normal online operations the DCS compares the set point to the JBR narrow range level and automatically positions the JBR level control valve based on measured flow into and out of the JBR. The JBR make-up water header flow, JBR level control flow, JBR limestone slurry flow and pre-quench flow are all used to determine flow into the JBR. Gypsum drawoff and estimated evaporation losses based on unit load are used to determine flow out of the JBR. In bypass operations or upon loss of normal input signals, JBR level control does not consider JBR inlet and outlet flows when positioning the JBR level control valve. JBR slurry density is also controlled to maintain the rapid precipitation of gypsum during JBR operations. The DCS monitors JBR slurry density in the Gas Cooling System, Gypsum Drawoff Flow, and JBR level to adjust the gypsum drawoff flow control valve to maintain JBR density at 20% solids by weight.

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The JBR utilizes several wash systems to minimize the build-up of solids in the various sections of the JBR and to minimize the flue gas differential pressure across the JBR. The JBR deck wash continually sprays the sparger deck and sparger tubes with gas cooling slurry. The JBR wall and gas riser wash sprays the outer surface of the gas riser and the inner surface of the JBR wall just below the sparger plenum roof with make-up water on a timed cycle controlled by the DCS. These wash sprays minimize the build-up of fly ash and scaling that may occur in these areas of the JBR. The mist eliminator uses make-up water to spray the upper and lower sections of the mist eliminator. The lower spray washes the inlet side of the lower section and the upper spray washes the outlet side of the lower section and the inlet side of the upper section. In addition to wash systems, JBR level, pressure, and differential pressure transmitter legs are automatically flushed with make-up water to prevent a build-up of solids. The flush cycle for each transmitter is dictated by the cycle of the specific wash system that supplies the flush water. Additionally, the reference leg of the JBR level transmitters is equipped with a continuous air purge to prevent corrosive flue gas from damaging the transmitter. The JBR consists of the JBR vessel with integral inlet plenum, sparger deck, sparger tubes, gas riser, mist eliminators, mounted JBR mixers, wash systems, and instrumentation for level, pressure, density, and pH control. The JBR vessel has penetrations for receiving untreated flue gas, oxidation air, mist eliminator header drain water, stack drains, gypsum drawoff pump recirculation, JBR level make-up water, observation port flush water, gas cooling duct drains, and limestone slurry. The JBR vessel also has connections for slurry mixing, JBR gypsum reseeding, JBR vessel overflow, slurry density meter return, JBR vessel drains, gypsum drawoff pump suction, gas cooling pump suction, slurry sample collection, observation ports, access manways, flue gas exhaust, and level, pH, temperature, and pressure instrumentation. pH Control JBR slurry pH is a key, if not the most important, process control parameter for SO2 removal. It determines scrubber chemistry, and its control is paramount to establishing good scrubber operation.

Limestone is the reagent for the process, and it is added to the JBR in stoichiometric quantities to the incoming sulfur dioxide and the desired SO2 removal efficiency. This cannot be performed independently without consideration of the JBR slurry pH. A feed-forward feedback control algorithm is needed.

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The design pH setpoint is 5.2, but the JBR has the flexibility to operate anywhere within a range of about 4.0 to 5.5. JBR slurry pH is measured via three monitors in a median select configuration located two to three feet below the normal JBR liquid level. The pH feedback signal in conjunction with a calculated limestone demand feed-forward signal are used to determine the limestone slurry flow setpoint. That combined with a flow rate feedback signal sets the position of the limestone slurry flow control valve. This is a difficult application for a flow control valve. Experience has shown that a ceramic v-ball offers the best performance. A ceramic lined magnetic flow transmitter monitors the flowrate.

The pH control scheme should maintain reaction stability during unit load changes. A slow acting pH feedback controller is summed with a SO2 loading feed-forward signal to provide a setpoint for the limestone slurry flow controller. In response to sudden changes in SO2 loading, the setpoint is biased either upward (for increasing loading) or downward (for decreasing loading) over a several second period. Manual control of the limestone slurry flow control valve is provided via a manual/auto station.

During start-up the pH is typically about 7. With the limestone slurry storage pump operating, the limestone slurry flow control valve manual/auto station is placed in auto. High pH sets a latch which holds the pH trim controller output near zero, negating most of the limestone slurry demand from the feed-forward signal. As the JBR is brought into service, absorbed SO2 causes the pH to decrease. When the pH falls within 0.25 of the pH setpoint, the flow controller and pH trim controller are released to automatic and the output of the pH controller is bumped up to a value closer to the typical demand. A minimum limestone slurry flow is established when the latch releases the controllers. The objective of the latch is to starve the JBR until pH is very close to setpoint. With the controllers properly tuned, the amount of under-shoot is minimized, and the system is stable through start-up conditions.

Level Control The liquid level of the JBR has a direct effect on the SO2 removal achieved by the JBR. Increased level provides greater contact time between flue gas and slurry and thereby increased removal efficiency. JBR draft pressure loss increases directly with increased JBR liquid level. JBR pressure loss is a major, if not the largest component of total unit draft pressure loss. Therefore, control of JBR liquid level is very important to FGD system performance and unit operation.

The JBR liquid level is controlled continuously. The primary means of control is through the JBR level flow control valve. The JBR level setpoint is established by the desired removal efficiency. This level is referred to as the normal liquid level, NLL.

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Each JBR is equipped with three separate sets of level monitoring instrumentation: a narrow range JBR liquid hydrostatic pressure, wide range JBR liquid hydrostatic pressure, and sparger deck – gas riser draft pressure differential. All three sets are equipped for median select of three measurements.

The narrow range JBR liquid hydrostatic is utilized for dynamic JBR liquid level control. This level measurement provides a feedback signal to the JBR level flow controller. It is desired that this controller maintain the liquid level at setpoint. To accomplish this control the ICS performs a water balance about each JBR utilizing flow monitors in the incoming and outgoing streams. Monitored flows include the prequench, wash water, limestone slurry feed and gypsum slurry bleed. The quantity of water lost to evaporation in the flue gas is estimated by an algorithm based on unit load. The wide range level measurement provides the signal for operating alarms and interlocks for the pumps and mixers. These control parameters are depicted in the figure below.

Units 3 & 4 JBR Level Alarms & Interlocks Note that narrow range alarms are based on a selected NLL setpoint which is varied for performance. The values given here for NLL, NR High and NR Low are speculative.

- 4 inches of setpoint NR Low Alarm

118 in or 9.8 ft WR Low Low Alarm, Start Permit Mixers &Pumps

106 in or 8.8 ft WR Low Low Low Stops Mixers & Pumps Start Permit Ox Air Blowers

<+9 inches of setpoint Resume Washes & LS Feed

+4 inches of setpoint NR High Alarm

228 in or 19 ft Overflow

Narrow

Range

Wide R

ange

180 in or 15 ft WR Low Alarm

>+9 inches of setpoint Stops Washes & LS Feed

NR setpoint

-15 inches NR Opacity Excursion Alarm

<-18 inches NR Prevents bypass damper from being repositioned to the Scrubber online position

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Measurement of the draft pressure loss between the sparger deck and gas riser provides an alternate means of monitoring should problems be encountered with the use of liquid hydrostatic pressure. SO2 Control JBR %SO2 removal controller continuously manipulates the pH set-point and the JBR level set-point to automatically control the percentage of SO2 removal at the most efficient rate. The pH control range is limited to 5.0 to 6.0. JBR level control range is limited to -5 to -10 inches. If additional SO2 removal is required, the JBR level will be raised.

Density Control Gypsum solids are continuously produced by the JBR while in service. To preserve rapid precipitation of gypsum, the slurry suspended solids concentration is maintained at a setpoint of 20% solids by weight. This is accomplished by modulating the position of the density control valve in the gypsum draw-off pipeline, thereby adjusting the flow of slurry from the JBR to the gypsum transfer tank. The density of the gypsum slurry is continuously monitored by nuclear density meters installed in the slipstream off of the gas cooling spray. This measurement provides a feedback signal to the density controller. Wash Control

Control of wash water sprays on the gas riser, JBR wall, and mist eliminator is important for minimizing solids deposition and JBR differential gas pressure. The wash water valves are cycled by a sequencer. The sequencer is set to initiate wash events at set times, alternating units, and sequencing mist eliminator, wall, and riser washes for each unit. Logic prevents the simultaneous washing of any mist eliminator segment, JBR wall, or gas riser for more than one unit of each unit pair (Unit 3 & 4 or Unit 1 & 2) at a time. Mist Eliminator washes will occur at least three times per 24 hour day when the JBR is not bypassed. High Level and Low Density will no longer stop the washes. The number of washes each 24 hour day will be one per 100 MW of load. This means that at full load the number of washes will be 9 per day. At 550 MW, the number of washes per 24 hour day will be 5, and so on. There will always be at least three washes per 24 hour day, unless the JBR is bypassed. Since load changes during the day, the time between the current and the next scheduled wash will be calculated at the start of each wash. JBR deck wash is considered separate from mist eliminator and wall washing. It is a continuous action and has no control functionality.

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2603.301.3.2 S ys tem C omponents

The JBR Vessel System consists of the following:

• Jet Bubbling Reactor (JBR) Vessel

• JBR Sparger Tubes

• JBR Deck Wash System

• JBR Gas Riser and Wall Wash System

• JBR Mist Eliminator

• Lower and Upper Mist Eliminator Wash System

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2603.301.3.2.1 J et B ubbling R eac tor (J B R ) V es s el (S K -R X-5001)

Number Sheet Rev Title P&IDs

• D3M20008 1 3 P&ID – Jet Bubbling Reactor JBR Instrumentation

• D3M20009 1 3 P&ID – Jet Bubbling Reactor JBR Piping

• D3M20010 1 3 P&ID – Jet Bubbling Reactor Deck, JBR Shell & Gas Riser Wash

• D3M20011 1 2 P&ID – Jet Bubbling Reactor Lower Mist Eliminator Spray System

• D3M20012 1 3 P&ID – Jet Bubbling Reactor Upper Mist Eliminator Spray System

Function The JBR vessel (SK-RX-5001) is the component where the chemical process of SO2 scrubbing and gypsum production is accomplished. The basic process involves bubbling incoming flue gas through limestone slurry allowing a chemical reaction to remove flue gas Sulfur Dioxide (SO2) and produce a usable gypsum byproduct, and discharge the treated flue gas into the atmosphere. The CT-121 design is unique in that it allows the five primary chemical processes involved with SO2 removal and gypsum production to occur simultaneously in the same vessel. Absorption of SO2 Oxidation of acid sulfites to acid sulfates Limestone dissolution Neutralization of acid sulfates to form gypsum Production and growth of gypsum crystals

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Des c ription

The JBR is based on the CT-121 Thoroughbred Jet Bubbling Reactor (JBR) technology of Chiyoda Corporation of Yokohama, Japan. The JBR vessel is 54’ 6” high and 119’ diameter with a liquid volume of 1,414,000 gallons and is primarily constructed of Fiberglass Reinforced Plastic (FRP).

JBR Size

Diameter A 108 119

Height B 52.5 54.5

Normal Liquid Level (NLL) C 16.04 17.04

NLL to Top of Alignment Grid K 0.33 0.33

Top of Alignment Grid to Top of Sparger Deck L 14.125 14.125

Top of Concrete to Top of Sparger Deck M 30.5 31.5

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Thermal protection of JBR components is required, since the majority of JBR components are constructed of Fiberglass Reinforced Plastic (FRP) and the most temperature limiting JBR component (sparger tubes) have a 155 oF limit due to their Polyvinyl Chloride (PVC) construction. The slurry in the JBR vessel is divided into two zones, the jet bubbling zone and the reaction layer. The jet bubbling zone is a layer of froth composed of bubbles that continually form and collapse. This froth layer is formed when the untreated flue gas enters the JBR and is accelerated as it passes down through the multiple sparger tubes, then bubbles out beneath the surface of the slurry.

The jet bubbling zone or froth layer, provides the gas liquid contact area in the JBR where SO2 in the flue gas dissolves in the liquid film on the surface of the bubbles. The bubbles provide a large surface area inside the jet bubbling zone. Fly ash inside the flue gas also contacts the liquid film and is captured.

Other acid gases such as hydrochloric acid and hydrofluoric acid are also absorbed at high levels. SO2 removal is further enhanced by the successive rapid collapse and formation of bubbles in the jet bubbling zone. This action continually regenerates fresh interfacial area and transports reaction products away from the jet bubbling zone into the reaction zone, and then brings fresh reactants into contact with the flue gas.

JBR slurry pH, level, and density are controlled by the DCS to ensure optimum SO2 removal and gypsum production. In addition, the Oxidation Air System is used to force oxidation air into the slurry through a total of 352 sparger legs located in 12 oxidation zones spaced evenly around the JBR vessel.

All treated flue gas exiting the JBR passes through two banks of mist eliminators where moisture droplets entrained in the flue gas is removed and allowed to fall back to the JBR vessel by gravity.

The JBR vessel has four low speed mixers mounted on the roof of the vessel structure. These mixers work in conjunction with the oxidation air and the sparging effect created by the incoming flue gas to ensure adequate mixing of JBR slurry to refresh the reactants in the jet bubbling zone.

Continuous operation of the mixers is required to maintain JBR SO2 removal efficiency. The mixers also serve to maintain slurry solids in suspension to prevent deposition in the bottom of the JBR vessel. Mixers 2 & 4 rotate in a clockwise direction and mixers 1 & 3 rotate in a counter clockwise direction to promote good mixing and suspension in the JBR Vessel. The shaft of each mixer extends through the JBR Vessel top and into the JBR slurry reaction zone below the gas sparger tubes 60 inches above the vessel floor.

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All treated flue gas exiting the JBR passes through two banks of mist eliminators where moisture droplets entrained in the flue gas is removed and allowed to fall back to the JBR vessel by gravity.

Sparger Deck

Mist Eliminator

Gas Inlet

Gas Outlet

Gas Riser

Mixer (1 of 4)

Sparger Tubes JBR Internal Components, Gas Riser, & Mist

Eliminator

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2603.301.3.2.2 J B R S parger T ubes







Vendor O&M Manuals

• S90677 Scrubber-FGD- JBR Inlet Duct Internal Piping- Quality Manual

• S82788 1 A FGD - Scrubber - JBR Sparger Tube Alignment Grid Module Sheet 2

• S82789 1 A FGD - Scrubber - JBR Sparger Tube Alignment Grid - Details Sheet 3

Function

The JBR sparger tubes are located in the sparger deck and direct the incoming flue gas from the sparger plenum down into the JBR slurry and distribute the flow. The sparger tubes play an important role in the SO2 removal efficiency of the JBR due to their submergence depth (JBR Level) and outlet holes which promote mixing of reactants.

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Des c ription

The 4968 JBR sparger tubes are constructed of 6” Polyvinyl Chloride (PVC) pipe and have a total length of 17’ 5 ½”. The sparger tubes are the most temperature limiting component in the JBR with a 155 oF temperature limit. This temperature limit requires that the 355 oF flue gas be cooled by pre-quench and gas cooling spray to protect the sparger tubes from damage.

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2603.301.3.2.3 J B R Dec k Was h S ys tem







• D3M20070 1 2 P&ID – JBR Internal Deck Wash System Vendor O&M Manuals

• S52284 1 A FGD - Scrubber - 2 1/2" TSC As A-90 Deck Wash Nozzle

• S81397 1 C FGD - Scrubber - 2 1/2" TSC 87 A-90 Deck Wash Nozzle

• S85399 1 A FGD - Scrubber - 2 1/2" TSC 87 A-90 Deck Wash Nozzle - Final Inspection Report

Function

The JBR Deck Wash System minimizes the build-up of fly ash and scaling on the sparger deck and in the sparger tubes to maintain the differential pressure across the JBR at a minimum. The JBR deck wash system continuously sprays JBR slurry from the Gas Cooling System onto the top side of the JBR sparger deck any time a gas cooling pump is in operation. The slurry washes the sparger deck and flows down into the sparger tubes to prevent sparger tube plugging. There are no control valves associated with the deck wash system, since it is in continuous operation.

Typical Deck Wash Nozzles

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Des c ription

The deck wash spray nozzles are BETE model TSC87A-90, Full Cone type with a 90 ±10o Spray Angle rated at 60 ± 10% gpm @ 21.3 psi, constructed of Silicon Carbide with a 2½ ” Victaulic connection. The 120 deck wash nozzles are distributed over a 30 branch U-shaped headers providing spray coverage for all, except the gas inlet duct side of the sparger deck. The nozzle placement on the spray headers produces a downward spray in the same direction as the flue gas flow.

Spraying Fluid Characteristics Fluid Name Gypsum Slurry Temperature (oF) 133 Specific Gravity, range/design 1.0-1.15 / 1.13 pH 3.5 – 6.0 Fluid Composition:

Suspended Solids (wt%) 0 – 25 Dissolved Solids (mg/L) 10 – 50,000 Max. Chlorides (mg/L) 20,000

Exposure Description Saturated flue gas Temperature (oF) ≤ 135 SO2 (ppmd) ≤ 1750 SO3 (ppmd) ≤ 17 Particulate (grains/scfd) ≤ 11 H2O lb H2O/lb dry gas) 0.121

Spray Nozzle Specifications Manufacturer BETE Model TSC 87 A-90 Type Full Cone Quantity for Units 3&4, each 120 Materials of Construction Nitrogen Bonded Silicon Carbide Spraying Pressure (psid) 21.3 Flow Rate (gpm) 60 ± 10% K factor value 13.76 Exponent value 0.5 Spray Angle (degrees) 95 ± 10o Nozzle Orientation Tangential Minimum Passage Diameter (mm) 25 Spray Orientation Vertical (down) Spray Direction Relative to Gas Flow Co-current Connection Victaulic coupling

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Deck Wash Headers

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2603.301.3.2.4 J B R G as R is er and Wall Was h S ys tem







• D3M20071 1 2 P&ID - Jet Bubbling Reactor Riser Wash System

• D3M20072 1 1 P&ID - Jet Bubbling Reactor Wall Wash System Vendor O&M Manuals

• S52287 1 0 FGD - Scrubber - 3/8" MP 218 A-115 Wall Wash Nozzle

• S81395 1 A FGD - Scrubber - 1/2" MP 218 A-110 Wall Wash Nozzle

• S85397 1 0 FGD - Scrubber - 1/2" MP 218 A-110 Wall Wash Nozzle - Final Inspection Report

Function

The JBR Gas Riser and Wall Wash Systems minimize the build-up of fly ash and scaling to maintain the differential pressure across the JBR at a minimum. The gas riser wash sprays the outer surface of the JBR gas riser and the wall wash sprays the inner surface of the JBR wall in the sparger plenum, just below the plenum roof. A two minute wash is performed every two hours for each system starting with the gas riser wash, then followed by the wall wash 60 minutes later. The timed spray cycles are controlled by the DCS and coordinated with other wash systems to ensure only one JBR wash system is in operation at a time. The DCS controls Make-Up Water System isolation valves MU-XV-5421 for gas riser wash and MU-XV-5431 for wall wash operations.

The gas riser wash spray header also provides instrument flush water to JBR differential pressure transmitter C (SK-PDIT-5711C) and the mist eliminator differential pressure transmitter (ME-PDIT-5741). These instruments are flushed with each gas riser wash cycle.

The make-up water header supplying the gas riser and wall wash systems also supplies the flush water for the center JBR vessel observation port. Flush water is controlled by a manual valve at the observation port. The center observation port is supplied off the main make-up water distribution header.

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Des c ription

The gas riser and wall wash spray nozzles are BETE model MP218A-110, Full Cone type with a 110 ±10o Spray Angle rated at 7.25 ± 10% gpm @ 28.5 psi, constructed of Polypropylene with ½ ” male NPT threads. The 85 gas riser nozzles and 144 wall wash nozzles are evenly distributed on a U-shaped header for each wash spray providing coverage for all, except the gas inlet duct side of the sparger plenum. The gas riser nozzles are located 16-18” off the gas riser and 1’ 6 ½” below the plenum roof. The wall wash nozzles are located 16-19” off the wall and 1’ 1” below the plenum roof. The nozzle placement on the spray headers produces an axial spray that is perpendicular with flue gas flow.

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Spraying Fluid Characteristics Fluid Name Make-up Water Temperature (oF) 32-100 Specific Gravity, range/design 1.0-1.04 / 1.02 pH 7 - 9.5 Fluid Composition:

Suspended Solids (wt%) 0 Dissolved Solids (mg/L) 10 – 150 Max. Chlorides (mg/L) 50

Exposure Description Saturated flue gas Temperature (oF) ≤ 135 SO2 (ppmd) ≤ 1750 SO3 (ppmd) ≤ 17 Particulate (grains/scfd) ≤ 11 H2O lb H2O/lb dry gas) 0.121

Spray Nozzle Specifications Manufacturer BETE Model MP 218 A-110 Type Full Cone Quantity for Units 3&4, each 229 Materials of Construction Polypropylene Spraying Pressure (psid) 28.5 Flow Rate (gpm) 7.25 ± 10% K factor value 1.517 Exponent value 0.47 Spray Angle (degrees) 110 ± 100

Nozzle Orientation Axial Minimum Passage Diameter (mm) 5 Spray Orientation axial Spray Direction Relative to Gas Flow perpendicular Connection Threaded male

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Riser Wash Header Arrangement

Wall Wash Header Arrangement

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2603.301.3.2.5 J B R Mis t E liminator







Vendor O&M Manuals


• S81430 1 F Scrubber - FGD - Mist Elimination System - General Arrangement

• S82393 1 C Scrubber - FGD - Mist Elimination System - General Arrangement - Lower Spray Wash System

• S81432 1 A Scrubber - FGD - Mist Elimination System - Operation & Maintenance Manual

Function

The Mist Eliminator removes entrained slurry droplets from the exhaust path and prevents their expulsion into the atmosphere. The process of slurry droplet removal is achieved over two stages. Each stage of the mist eliminator serves to remove finer mist droplets than the preceding stage.

Des c ription

The mist eliminator (ME) is a set of vanes that form a convoluted path to remove moisture droplets entrained in the treated gas stream. The mist eliminator vanes span the entire diameter of the gas riser. They are divided into an upper and lower bank. The inlet face and outlet of the first bank as well as the inlet face of the second bank require frequent washing.

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The washing of the ME 1st bank back and the 2nd bank face is combined in one pipe header. The wash spray headers and nozzles are included in the mist eliminator supply scope. The following figures depict mist eliminators.

The JBR Mist Eliminator is a Munters model DV210 two stage high velocity vane type separator constructed of Fiberglass Reinforced Plastic (FRP) with integral wash headers. The mist eliminators consists of an upper and lower bank of convoluted vanes where moisture droplets entrained in the treated flue gas are removed and allowed to fall back to the JBR vessel by gravity.

Quantity of banks 2

Gas Riser Diameter 68 ft

Manufacturer & Model Munters DV210

ME Vanes Material FRP

ME Wash Nozzle Mfr & Model Bete 3/8” MP125M & ½” MP187M

ME Wash Nozzle Quantity 1800 & 900

ME Wash Nozzle Flow 2.7 & 5.4 gpm

ME Wash Nozzle Pressure 40 psig

Max Instantaneous Wash Water Rate 713 gpm @ 40 psig

All flue gas leaving the JBR passes through both sets of the mist eliminators. The lower mist eliminator stage is considered a Gross Entrainment Separator with smooth one piece profiles having a profile spacing of 38 mm. The upper mist eliminator stage is considered a Fine Entrainment Separator with smooth one piece profiles having a profile spacing of 32 mm.

The mist eliminators are equipped with spray wash systems to minimize the build-up of solids to prevent plugging. The mist eliminator wash systems use make-up water to spray the upper and lower sections of the mist eliminator. The lower spray system washes the inlet side of the lower section.

The upper spray washes the outlet side of the lower section and the inlet side of the upper section. The mist eliminator module is equipped with a sliding view door, allowing inspection of the mist eliminators and wash headers between the stages.

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One stage of the Mist Eliminator

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2603.301.3.2.6 L ower and Upper Mis t E liminator Was h S ys tem







Vendor O&M Manuals





Function

The mist eliminator wash systems use make-up water to minimize the build-up of solids in the mist eliminator elements and prevent plugging. The Lower Mist Eliminator Wash System washes the inlet side of the lower mist eliminator section. The Upper Mist Eliminator Wash System washes the outlet side of the lower section and the inlet side of the upper section. The outlet side of the upper section is not washed. The wash headers are integral with the mist eliminator modules and are supplied with separate control valves operated by the DCS. A 60 second wash is performed every eight hours for each header with a 5 minute delay, between cycling each valve. The cycle starts with the lower wash valves then completes the wash cycle with the upper wash valves. The timed spray cycles are controlled by the DCS and coordinated with other wash systems to ensure only one JBR wash system is in operation at a time. The DCS also ensures that a minimum of one wash cycle occurs daily even during abnormal operations. The main mist eliminator supply header can be drained to the JBR vessel with the installed manual drain valve.

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Mist eliminator spray header 17 (ME-XV-5458) also provides instrument flush water to JBR differential pressure transmitter A (SK-PDIT-5711A) and the JBR pressure transmitter (FG-PIT-5735). Mist eliminator spray header 8 (ME-XV-5448) also provides instrument flush water to JBR differential pressure transmitter B (SK-PDIT-5711B). These instruments are flushed with each mist eliminator wash cycle.

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Des c ription

The mist eliminator spray nozzles are BETE model MP187M (lower) / MP125M (upper), Full Cone type with a 90 ±10o Spray Angle rated at 5.4 / 2.7 ± 10% gpm @ 40 psi, constructed of Polypropylene with 1/2” / 3/8” NPT threads. There are 900 spray nozzles distributed over nine lower mist eliminator spray headers. Additionally, there are 1800 spray nozzles distributed over nine upper mist eliminator spray headers.

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2603.301.3.3 S ummarized J B R L evel C ontrol

JBR liquid level is an extremely important process to maintain. Liquid level in the JBR has a direct effect on the SO2 removal efficiency. Increased level provides greater contact time between flue gas and slurry, thereby increasing removal efficiency. However, increased level also reduces draft pressure. JBR pressure loss is a major, if not the largest, component of total unit draft pressure loss. Three sets of level monitoring instrumentation provide three controllers the process information needed to maintain JBR Level.

2603.301.3.4 Detailed J B R L evel C ontrol

Three separate sets of level monitoring instrumentation are used to measure JBR level, Narrow Range, Wide Range and Sparger Deck/Gas Riser Draft Pressure differential. Wide Range measurement is the median select of three liquid hydrostatic pressure transmitters ranged 0-180 inwc. This measurement is used for operating alarms, as well as pump and mixer interlocks. Narrow Range measurement is the median select of three liquid hydrostatic pressure transmitters ranged 0-36 inwc. This measurement provides inputs to JBR Flow, Multi and Single element controllers which work together to maintain JBR level at setpoint. Sparger Deck/Gas Riser Draft differential pressure measurement is the median select of three differential pressure transmitters ranged 0-30 inwc. This measurement provides an alternate means of monitoring level should Narrow and Wide range measurements fail. The Unit 3 liquid hydrostatic pressure transmitter measurement legs are flushed with make-up water three times daily, at 0700, 1500, and 2300. Auto-flush logic cycles three transmitter auto-flush valves (WF-XV-5020A, B &C) opened and closed in sequence, so that only one set of transmitter legs are flushed at any given time. If a transmitter auto-flush valve controller is not in automatic, the logic skips that valve and the sequence continues. A manual flush for an individual transmitter can be initiated at any time, provided permissives are met. If at least one flush does not take place within a 24-hour period, an alarm is annunciated.

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The following table illustrates the permissives needed for a transmitter flush to take place: T rue Not T rue

BYPASS DAMPER In FGD Bypass Position X JBR WR LEVEL Signal Deviation X JBR NR LEVEL Signal Deviation X JBR WR LEVEL >19 X JBR WR LEVEL < 8.8’ X

CORRESPONDING JBR LEVEL TRANSMITTER

FLUSH VALVE AUTO X

REMAINING JBR LEVEL TRANSMITTERS FLUSHING X

JBR liquid level principal means of control is through JBR LEVEL CONTROL VALVE (SK-LV-5030). A Manual/Auto Station positions the valve. When in AUTO, the station receives its position setpoint from either the Multi Element and Flow controllers or the Single Element Controller. The Multi Element Controller uses a pre-determined JBR level that achieves a desired SO2 removal efficiency as its setpoint. This value is referred to as the Normal Liquid Level or NLL. When active, the controller compares NLL to JBR Narrow Range Level measurement and adjusts its output to compensate for any deviation between the two values. The output of the Multi Element Controller is summed with liquid flow out of the JBR. Liquid flow out is achieved by relating plant load with a loss of liquid through evaporation and adding it with Gypsum Draw Off Flow. The Flow Controller uses liquid flow out of the JBR summed with Multi Element Controller output as its setpoint. The controller compares liquid flow out of the JBR to liquid flow into the JBR and adjusts its output to compensate for any deviation between the two values. Liquid flow into the JBR is the summation of Make-Up Water, Level Control, Limestone Slurry and Pre-Quench flows. Both the Multi Element and Flow controllers working together are the primary means of level control. The Single Element Controller uses NLL as its setpoint. When active, the controller compares NLL to JBR Narrow Range Level measurement and adjusts its output to compensate for any deviation between the two values. When the Single Element Controller is inactive or the Level Control Valve Manual Auto Station is in Manual, its output tracks to current Level Control Valve position. This is to provide bumpless transfer when transfer of control takes place.

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Control is transferred from the Multi Element and Flow controllers to the Single Element controller if one or all of the following conditions occur:

• JBR MAKE UP HEADER FLOW (MU-FIT-5135) signal flagged bad

• JBR LEVEL CONTROL FLOW (SK-FIT-5030) signal flagged bad

• GYPSUM DRAWOFF FLOW (GD-FIT-5654) signal flagged bad

• JBR LS SLURRY FLOW A&B (LS-FIT-5589A&B) signals flagged bad

• JBR PREQUENCH SPRAY FLOW A&B (PQ-FIT-5132A&B) signals flagged bad

• FGD Diverter Damper is NOT in the ONLINE position

• FGD Diverter Damper Position signal flagged bad

• Unit Load Signal is flagged bad

• SINGLE ELEMENT OVERRIDE has been toggled

When the Single Element Controller is active, the Multi Element and Flow controllers are inactive. When inactive or Level Control Valve Manual Auto Station is in Manual, the output of the Multi Element Controller tracks the difference between JBR flow in and JBR flow out, while the output of the Flow Controller tracks current Level Control Valve position. This is to provide bumpless transfer when transfer of control takes place.

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2603.301.3.5 S ummarized J B R pH C ontrol

JBR slurry pH is a key control parameter for SO2 removal. It determines scrubber chemistry and its control is paramount to establishing good scrubber operation. The addition of limestone to maintain desired SO2 removal efficiency cannot be performed without considering JBR slurry pH. The measurement of JBR slurry pH and Limestone Slurry Flow makes determining a limestone slurry flow setpoint possible. A Limestone Slurry Flow Controller and a JBR pH controller work together to maintain pH.

2603.301.3.6 Detailed J B R pH C ontrol

JBR slurry pH measurement is the median select of three pH transmitters ranged 0-10 pH. This measurement provides DCS indication and input to the JBR pH Controller. JBR Slurry Flow measurement is the average of two ceramic lined magnetic flow transmitters ranged 0-500 gpm. This measurement provides DCS indication and input to the Limestone Flow Controller. Limestone Slurry Density measurement is the average of two density transmitters. This measurement provides DCS indication and as a bias the feed forward calculation. JBR slurry pH principal means of control is through the JBR Limestone Flow Control Valve. A Limestone Slurry Flow Controller equipped with a manual auto station positions the valve. The Limestone Flow Controller uses JBR pH Controller output as its setpoint. When in auto, the controller compares JBR pH Controller output to Limestone Slurry Flow and adjusts valve position to compensate for any deviation between the two values. To prevent possible plugging or sticking, the DCS automatically cycles the valve fully open and fully closed then releases it back to setpoint once a day. The JBR pH Controller uses a predetermined pH value of 5.2 as its setpoint. This value is by design, though it is possible to maintain a range of 4.0 to 5.5. When active, the controller compares pH setpoint to JBR Slurry pH measurement and adjusts its output to compensate for any deviation between the two values. A feed forward control is used to compensate for unit load changes. Output of the JBR pH Controller is biased either upward for increasing load, or downward for decreasing load over a several second period. This is to anticipate change in pH due to increase or decrease of absorbed SO2. Limestone Slurry Density measurement is used to bias the feed forward calculation. During start-up, the JBR pH is typically about 7. High pH sets a latch which holds the JBR pH Controller output near zero. As the JBR is brought into service, absorbed SO2 causes the pH to decrease. When pH falls within 0.25 of setpoint, the Limestone Flow Controller and JBR pH Controller are released to automatic. When the controllers are released, output of the pH controller is increased to a value closer to typical demand and the Limestone Flow Controller establishes minimum limestone slurry flow. This is to minimize the deviation between pH and setpoint, and stabilize system during start up conditions.

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2603.301.3.7 S ummarized S O 2 C ontrol

The So2 controller allows control of the JBR pH Controller and the JBR Level controller to maintain the most efficient Scrubber operation at > 95% So2 removal rate. The SO2 controller changes the pH controller and the Level control set points to the optimum setting for SO2 removal. 2603.301.3.8 Detailed S O 2 C ontrol

Control of JBR %SO2 removal to JBR is continuously manipulating pH set-point and JBR level set-point to automatically control > 95% SO2 removal. The control is set at 97.5% The pH control range is limited to 5.0 to 6.0. JBR level control range is limited to -5 to -10 inches. The pH high alarm limit is 5.5 to 6.2 to avoid nuisance alarms. In order to minimize station service, %SO2 removal controller will primarily manipulate pH control set-point. If additional SO2 removal is required, the JBR level will be raised. The operator may can place the controller in manual and leave the pH and level controllers in manual. This will allow the operator to change the output value of the SO2 removal controller in turn will adjust the pH controller setpoints and the level control setpoints, this is provided they are in automatic and have the SETPOINT SO2 CONTROL selected on the pH and level controllers.

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2603.301.3.9 S ummarized J B R Dens ity C ontrol

Gypsum solids are continuously produced by the JBR while in service. To preserve rapid precipitation of gypsum, the slurry suspended solids concentration is maintained at a setpoint of 20% solids by weight. This is accomplished by modulating the position of the density control valve in the gypsum draw-off pipeline, thereby adjusting the flow of slurry from the JBR to the gypsum transfer tank. The measurement of JBR Slurry Density and Gypsum Drawoff Flow makes determining a Gypsum Drawoff Flow setpoint possible. A Gypsum Drawoff Flow Controller and Density Controller work together to maintain density. JBR Slurry Density measurement is the average of two nuclear density meters ranged 0-35%. This measurement provides input to the JBR Density Controller. Gypsum Drawoff Flow measurement is measured by one flow transmitter ranged 0-1500 gpm.

2603.301.3.10 Detailed J B R Dens ity C ontrol

JBR Density principle means of control is through JBR Gypsum Drawoff Flow Control Valve (GD-DV-5655). The Gypsum Drawoff Flow Controller equipped with a manual auto station positions the valve. The Gypsum Drawoff Flow Controller uses JBR Density Controller output as its setpoint. When in auto, the controller compares JBR Density Controller output to Gypsum Drawoff flow and adjusts valve position to compensate for any deviation between the two values. To prevent possible plugging or sticking, the DCS automatically cycles the valve fully open and fully closed then releases it back to setpoint once a day. The JBR Density Controller uses a predetermined density value of 20% solids by weight as its setpoint. When in auto, the controller compares density setpoint to JBR Slurry Density measurement and adjusts its output to compensate for any deviation between the two values. If JBR Narrow Range Level reaches 18’ the density control valve position setpoint is increased to assist in the reduction of level.

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2603.301.3.11 S ummarized J B R Was h C ontrol

The Wash Systems minimize flue gas solid deposits and JBR differential gas pressure by spraying/washing down JBR Deck, Wall, Gas Riser and Upper and Lower Mist Eliminators. JBR Deck, Wall, Gas Riser and Upper and Lower Mist Eliminator systems make up the JBR Wash Systems. Each system is automatically controlled via DCS using sequencing logic. The sequence logic momentarily opens each wash valve individually (if in auto) preventing the simultaneous washing of any system. A manual override selection allows for start and stop of the sequencing logic.

2603.301.3.12 Detailed J B R Was h C ontrol

Deck Wash The JBR deck wash is considered separate from mist eliminator and wall washing. It uses slurry from the Gas Cooling Pumps to continuously wash the topside of the sparger deck and sparger tubes. This is a continuous function during JBR operation and requires no control function. Gas Riser and Wall Wash JBR Gas Riser and Wall Washes are scheduled to start every two hours. Each valve is open for two minutes beginning with the Gas Riser Wash Valve followed by the Wall Wash Valve 60 minutes later. If JBR Narrow Range Level is > setpoint +9 inches, and JBR Density is LOW, Gas Riser and Wall Washes are prevented with exception of every fourth wash in the sequence. Mist Eliminators

• Mist Eliminator washes will occur at least three times per 24 hour day when the JBR is not bypassed. High Level and Low Density will no longer stop the washes.

• The number of washes each 24 hour day will be one per 100 MW of load. This means that at full load the number of washes will be 9 per day. At 550 MW, the number of washes per 24 hour day will be 5, and so on. There will always be at least three washes per 24 hour day, unless the JBR is bypassed. Since load changes during the day, the time between the current and the next scheduled wash will be calculated at the start of each wash.

• The washes are 60 seconds per valve with 5 minutes between each valve.

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2603.301.4 P roc es s F low Des cription J B R F lue G as F low Process Flow

S tep 1.

Quenched flue gas enters the JBR vessel from the gas cooling duct and flows around the sparger plenum above the sparger deck. The flue gas flows down through the sparger tubes into the deck where it contacts the slurry in the lower JBR vessel where the SO2 removal process begins. The flue gas exits the sparger tubes below the slurry surface where enhanced slurry contact completes the SO2 removal process as the gas bubbles through the slurry. Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

S tep 2.

Treated flue gas then rises up through a central gas riser where it contacts the mist eliminators before exiting the JBR. The treated flue gas passes through the two banks of mist eliminators where moisture droplets entrained in the flue gas are removed before the flue gas exits the JBR into the flue gas handling duct. Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

S tep 3.

JBR inlet flue gas temperature is monitored using triple redundant temperature elements (FG-TE-5731A, B, and C). Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

S tep 4.

JBR pressure is monitored using a single pressure transmitter (FG-PIT-5735) and JBR differential pressure is monitored using triple redundant differential pressure transmitters (SK-PDIT-5711A, B, and C). Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

S tep 5.

Differential Pressure across the JBR mist eliminators is monitored by a single differential pressure transmitter (ME-PDIT-5741). Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

J B R L imes tone S lurry F low

S tep 6.

Limestone Slurry enters the JBR from the Limestone Slurry Transfer System and flows through a main header before branching off to four branch legs which penetrate the sparger deck. The slurry flows down through the four branch legs out into the JBR slurry 11’ 6” above the vessel bottom. Each branch leg delivers slurry to an associated JBR mixer approximately 3’ above and 1’ inside the radius of the mixer blades. Refer to Drawing No. D3M20069, Sheet 1, Rev 0, P&ID - Limestone Supply System JBR Internal Piping.

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2603.301.4 P roc es s F low Des cription J B R G as C ooling F low

S tep 7.

JBR slurry is withdrawn from the JBR by the two operating gas cooling pumps through individual 42” pump suction headers to cool the flue gas entering the JBR to protect it from thermal damage. Refer to Drawing No. D3M20009, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Piping.

S tep 8.

Any residual gas cooling flow draining from the gas cooling ducts returns to the JBR through six 42” drain headers. Refer to Drawing No. D3M20009, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Piping.

Gypsum Drawoff Flow

S tep 9.

Gypsum Slurry is withdrawn from the JBR vessel by the operating Gypsum Drawoff Pump through individual 8” pump suction headers for JBR slurry density control and pump recirculation. Refer to Drawing No. D3M20009, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Piping.

S tep 10.

Gypsum Slurry from the Gypsum Pump recirculation line is returned to the JBR through a 6” header with an installed dip tube. Refer to Drawing No. D3M20009, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Piping.

Density Meter Return Flow

S tep 11.

JBR slurry which has passed through the density meter in the Gas Cooling System is returned to the JBR vessel through a 3” return header with an installed spray nozzle. Refer to Drawing No. D3M20009, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Piping.

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2603.301.4 P roc es s F low Des cription JBR Deck Wash Flow

S tep 12.

JBR slurry is continuously provided by the Gas Cooling System for JBR deck wash and splits into 30 individual deck wash spray headers before entering the JBR sparger plenum. Flow for branch headers 11 & 12 pass through an expansion joint prior to entering the JBR. Refer to Drawing No. D3M20010, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor Deck, JBR Shell, & Gas Riser Wash.

S tep 13.

After the branch headers enter the sparger plenum the wash slurry is evenly distributed to each of the headers spray nozzles where flow is sprayed onto the sparger deck to wash down fly ash and any solids. Refer to Drawing No. D3M20070, Sheet 1, Rev 2, P&ID - Deck Wash System JBR Internal Piping.

JBR Gas Riser Wash and Instrument Flush Flow

S tep 14.

The Make-Up Water System supplies water to the JBR for gas riser wash spray through a gas riser wash valve (MU-XV-5421) controlled by the DCS. When opened the wash valve supplies make-up water to the main wash header and enters the JBR sparger plenum. Refer to Drawing No. D3M20010, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor Deck, JBR Shell, & Gas Riser Wash.

S tep 15.

After the main header enters the sparger plenum the wash water flows through a U-shaped header where flow is evenly distributed and sprayed onto the gas riser to wash down fly ash and any solids. Refer to Drawing No. D3M20071, Sheet 1, Rev 2, P&ID - Gas Riser Wash System JBR Internal Piping.

S tep 16.

Opening of the gas riser wash valve also directs make-up water to a branch header for instrument flush. The branch header further splits into two headers supplying flush water to one of three JBR differential pressure transmitters and the mist eliminator differential pressure transmitter. Refer to Drawing No. D3M20010, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor Deck, JBR Shell, & Gas Riser Wash.

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2603.301.4 P roc es s F low Des cription

S tep 17.

Flush water for JBR differential pressure transmitter C (SK-PDIT-5711C) flows through the header and splits to a flush line for the high and low side legs of the transmitter. Flow for each leg passes through a manual valve (MU147) and manual valves (MU148 & FG104) and flex hose before entering the leg and flushing into the JBR Vessel. Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

S tep 18.

Flush water for JBR Mist Eliminator differential pressure transmitter (ME-PDIT-5741) flows through the header and splits to a flush line for the high and low pressure legs of the transmitter. Flow for each leg passes through a manual valve (MU146 & 145) and flex hose before entering the leg and flushing into the JBR vessel. Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

JBR Wall Wash and Observation Port Flush Flow

S tep 19.

The Make-Up Water System supplies water to the JBR for wall wash spray through a wall wash valve (MU-XV-5431) controlled by the DCS. When opened the wash valve supplies make-up water to the main wash header and enters the JBR sparger plenum. Refer to Drawing No. D3M20010, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor Deck, JBR Shell, & Gas Riser Wash.

S tep 20.

After the main header enters the sparger plenum the wash water flows through a circular header where flow is evenly distributed and sprayed onto the JBR sparger plenum wall to wash down fly ash and any solids. Refer to Drawing No. D3M20072, Sheet 1, Rev 1, Wall Wash System JBR Internal Piping.

S tep 21.

The make-up water header supplying the gas riser and wall wash systems also supplies the flush water for the center JBR vessel observation port. Make-up water splits off the main header into a branch header supplying the observation port. Refer to Drawing No. D3M20010, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor Deck, JBR Shell, & Gas Riser Wash.

S tep 22.

Flush water for center observation port flows through the header and passes through a flex hose and a normally closed manual valve (WF135), directing flush water onto the observation port. Refer to Drawing No. D3M20009, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Piping.

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2603.301.4 P roc es s F low Des cription Lower Mist Eliminator Wash & Instrument Flow

S tep 23.

The Make-Up Water System supplies water to the nine lower mist eliminator spray valves ME-XV-5441 through 5449) off a common header through branch headers for each spray valve. Each spray valve header then further branches off to the upper mist eliminator headers before reaching the lower spray valves. Only one spray valve is opened at a time by the DCS on a timed cycle. The wash water flows through the open spray valve and continues through a flex hose before entering the gas riser spray headers. Once in the gas riser below the mist eliminator, the spray header branches off into two headers with spray nozzles which deliver wash water spray to the inlet side of the lower mist eliminator module. Refer to Drawing No. D3M20011, Sheet 1, Rev 2, P&ID - Jet Bubbling Reactor Lower Mist Eliminator Spray System.

S tep 24.

Opening of lower mist eliminator wash valve for header 8 (ME-XV-5448) also directs make-up water to a branch header for instrument flush of a JBR differential pressure transmitter. Refer to Drawing No. D3M20011, Sheet 1, Rev 2, Jet Bubbling Reactor Lower Mist Eliminator Spray System.

S tep 25.

Flush water for JBR differential pressure transmitter B (SK-PDIT-5711B) flows through the header and splits to a flush line for the high and low side legs of the transmitter. Flow for each leg passes through a manual valve (ME109) and manual valves (ME110 & FG103) and flex hose before entering the leg and flushing into the JBR vessel. Refer to Drawing No. D3M20008, Sheet 1, Rev 3, Jet Bubbling Reactor JBR Instrumentation.

Upper Mist Eliminator Wash & Instrument Flow

S tep 26.

The Upper Mist Eliminator System supplies water to the nine upper mist eliminator spray valves (ME-XV-5451 through 5459) off each of the lower spray valve headers upstream of the lower spray valves. Only one spray valve is opened at a time by the DCS on a timed cycle. The wash water flows through the open spray valve and continues through a flex hose before entering the gas riser spray headers. Once in the gas riser between the upper and lower mist eliminators, the spray header nozzles deliver wash spray to the outlet side of the lower mist eliminator module and the inlet side of the upper mist eliminator module. Refer to Drawing No. D3M20012, Sheet 1, Rev 3, Jet Bubbling Reactor Upper Mist Eliminator Spray System.

BWN-03-02603.301 Rev 1


2603.301.4 P roc es s F low Des cription S tep 27.

Opening of upper mist eliminator wash valve for header 17 (ME-XV-5458) also directs make-up water to a branch header for instrument flush of a JBR differential pressure transmitter and a JBR pressure transmitter leg. Refer to Drawing No. D3M20012, Sheet 1, Rev 3, Jet Bubbling Reactor Upper Mist Eliminator Spray System.

S tep 28.

Flush water for JBR differential pressure transmitter A (SK-PDIT-5711A) flows through the header and splits to a flush line for the high and low side legs of the transmitter. Flow for each leg passes through a manual valve (ME111 and manual valves (ME112 and FG102) and flex hose before entering the leg and flushing into the JBR vessel. Since the high side leg is also the pressure connection for the JBR pressure transmitter (FG-PIT-5735), this instrument leg is also flushed. Refer to Drawing No. D3M20008, Sheet 1, Rev 3, Jet Bubbling Reactor JBR Instrumentation.

JBR Level Transmitter Flush Flow

S tep 29.

The Water Flushing System supplies make-up water to the JBR level transmitters for flushing of the low and high side legs. The water flush supply header provides water to a common header that branches into the three flush valve headers. Only one flush valve is opened at a time by the DCS on a timed cycle to flush each of the three sets of transmitters. The wash water flows through a manual valves (WF101 through 103 and WF121 through 123) before passing through the open flush valve (WF-XV-5020AA, WF-XV-5020AB and manual valve (SK108), and WF-XV-5020AC and manual valve (SK111), WF-XV-5020BA, WF-XV-5020BB and manual valve (SK109), and WF-XV-5020BC and manual valve (SK112), AND WF-XV-5020CA, WF-XV-5020CB and manual valve (SK110), and WF-XV-5020CC and manual valve (SK113). Refer to Drawing No. D3M20008, Sheet 1, Rev 3, P&ID - Jet Bubbling Reactor JBR Instrumentation.

BWN-03-02603.301 Rev 1


2603.301.5 Drawing R eferenc es

The JBR Vessel System is illustrated on the following drawings:








• D3M20041 1 3 P&ID – Make-up Water Distribution

• D3M20052 1 2 P&ID – Mist Eliminator Area Compressed Air

• D3M20069 1 0 P&ID - Limestone Supply System JBR Internal Piping

• D3M20070 1 2 P&ID – Deck Wash System JBR Internal Piping

• D3M20071 1 2 P&ID – Gas Riser Wash System JBR Internal Piping

• D3M20072 1 1 P&ID – Wall Wash System JBR Internal Piping

Distribution Panels

• E3E30140 1 7 JBR 3/4 Electrical Bldg 120V Critical AC Panel A and Inverter

Functionals • D3F01130 1 0 Scrubber JBR Level Functional Control Diagram

• D3F01131 1 0 Scrubber Level Control Valve Functional Control Diagram

• D3F01132 1 0 Scrubber JBR Level Control Logic Functional Control Diagram

• D3F01133 1 0 Scrubber JBR Level Transmitter Flush Logic Functional Control Diagram

• D3F01134 1 0 Scrubber JBR Level Transmitter Flush Permits Functional Control Diagram

• D3F01135 1 0 Scrubber JBR Level Transmitter Flush Logic Functional Control Diagram

BWN-03-02603.301 Rev 1



Number Sheet Rev Title Functionals

• D3F01136 1 0 Scrubber JBR Level Transmitter A Flush Valve Functional Control Diagram

• D3F01137 1 0 Scrubber JBR Level Transmitter B Flush Valve Functional Control Diagram

• D3F01138 1 0 Scrubber JBR Level Transmitter C Flush Valve Functional Control Diagram

• D3F01140 1 0 Scrubber JBR Wash Control Master Logic Functional Control Diagram

• D3F01141 1 0 Scrubber JBR Shell And Wall Wash Schedule Functional Control Diagram

• D3F01142 1 0 Scrubber Mist Eliminator Wash Schedule Functional Control Diagram

• D3F01143 1 0 Scrubber JBR Shell And Gas Riser Wash Logic Functional Control Diagram

• D3F01144 1 0 Scrubber Mist Eliminator Wash Logic Functional Control Diagram

• D3F01145 1 0 Scrubber Mist Eliminator Wash Logic Functional Control Diagram

• D3F01150 1 0 Scrubber JBR Gas Riser Wash Valve Functional Control Diagram

• D3F01151 1 0 Scrubber JBR Shell Wash Valve Functional Control Diagram

• D3F01152 1 0 Scrubber JBR Lower Mist Eliminator Valve 5441 Functional Control Diagram






BWN-03-02603.301 Rev 1



Number Sheet Rev Title Functionals













• D3F01200 1 0 Scrubber JBR Density Measurement Functional Control Diagram

• D3F01201 1 0 Scrubber JBR Density Control Functional Control Diagram

• D3F01202 1 0 Scrubber JBR Density Control Logic Functional Control Diagram

• D3F01210 1 0 Scrubber JBR Measurements Functional Control Diagram

• D3F01211 1 0 Scrubber JBR Limestone Measurements Functional Control Diagram

• D3F01212 1 0 Scrubber pH Control Functional Control Diagram • D3F01213 1 0 Scrubber pH Control Logic Functional Control Diagram

BWN-03-02603.301 Rev 1



Number Sheet Rev Title DCS I/O Wiring Diagrams

• E3E30410 1 1 FGD Project - Wiring Diagram - JBR Elect Bldg DCS I/O Cabinet 3100 Power Supply

• E3E30410 2 2 FGD Project - Wiring Diagram JBR Elect Bldg DCS I/O Cabinet 3101 Base 0

• E3E30410 3 2 FGD Project - Wiring Diagram JBR Elect Bldg DCS I/O Cabine 3101 Base 0







• E3E30411 1 1 FGD Project - Wiring Diagram JBR Elect Bldg DCS I/O Cabinet 3103 Power Supply


• E3E30411 3 0 FGD Project - Wiring Diagram JBR Elect Bldg DCS I/O O Cabinet 3104 Base 0





BWN-03-02603.301 Rev 1



Number Sheet Rev Title DCS I/O Wiring Diagrams



• E3E30445 2 2 FGD Project Wiring Diagram DCS I/O Termination Cabinet Equipment No. EE-TC-7001

• E3E30445 3 2 FGD Project Wiring Diagram DCS I/O Termination Cabinet Equipment No. EE-TC-7001

Loop Diagrams • B3IMEP5741 1 0 Loop Sheet JBR Mist Eliminator DP ME-PDIT-5741

• B3ISKL5021 1 0 Loop Sheet JBR Narrow Range Level SK-LIT-5021A/SK-LIT-5021B/SK-LIT-5021C

• B3ISKL5022 1 0 Loop Sheet JBR Wide Range Level SK-LIT-5022A/SK-LIT-5022B/SK-LIT-5022C

• B3ISKP5711 1 0 Loop Sheet JBR Differential Pressure SK-PDIT-5711A/SK-PDIT-5711B/SK-PDIT-5711C

• B3IWFX5020 1 0 Loop Sheet JBR LVL IND XMTR A Flush Control Valve WF-XV-5020A

• B3IWFX5020 2 0 Loop Sheet JBR LVL IND XMTR A Flush Control Valve WF-XV-5020B

• B3IWFX5020 3 0 Loop Sheet JBR LVL IND XMTR A Flush Control Valve WF-XV-5020C

• B3ISKF5030 1 0 Loop Sheet JBR Level Control Flow SK-FIT-5030

• B3ISKF5030 2 0 Loop Sheet JBR Level Control Flow SK-FIT-5030

• B3IMUX5421 1 0 Loop Sheet JBR Gas Riser Wash Control Valve MU-XV-5421

• B3IMUX5431 1 0 Loop Sheet JBR Shell Wash Control Valve MU-XV-5431

• B3IMEX5441 1 0 Loop Sheet Lower Mist Eliminator Control Valve ME-XV-5441

BWN-03-02603.301 Rev 1



Number Sheet Rev Title Loop Sheets









• B3IMEX5451 1 0 Loop Sheet Upper Mist Eliminator Control Valve ME-XV-5451








BWN-03-02603.301 Rev 1



Number Sheet Rev Title Loop Sheets


• B3IMUX5421 1 0 Loop Sheet JBR Gas Riser Wash Control Valve MU-XV-5421

• B3IMUX5431 1 0 Loop Sheet JBR Shell Wash Control Valve MU-XV-5431

Vendor O&M Manuals

• S52284 1 A FGD - Scrubber - 2 1/2" TSC As A-90 Deck Wash Nozzle

• S52287 1 0 FGD - Scrubber - 3/8" MP 218 A-115 Wall Wash Nozzle

• S81395 1 A FGD - Scrubber - 1/2" MP 218 A-110 Wall Wash Nozzle

• S81397 1 C FGD - Scrubber - 2 1/2" TSC 87 A-90 Deck Wash Nozzle




• S82788 1 A FGD - Scrubber - JBR Sparger Tube Alignment Grid Module Sheet 2

• S82789 1 A FGD - Scrubber - JBR Sparger Tube Alignment Grid - Details Sheet 3

• S85397 1 0 FGD - Scrubber - 1/2" MP 218 A-110 Wall Wash Nozzle - Final Inspection Report

• S85399 1 A FGD - Scrubber - 2 1/2" TSC 87 A-90 Deck Wash Nozzle - Final Inspection Report

• S90677 1 A Scrubber-FGD- JBR Inlet Duct Internal Piping- Quality Manual

Procedure Revision Summary

Revision Document Change:

0

Initial release of document.

1

Added new SO2 controller to procedure

2

NOTE: See Revision Bars for specific changes within document.

Date post:	03-May-2018
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