ML19259C239

Process Control Program for Waste Solidification.

ML19259C239
Person / Time
Site:	Prairie Island
Issue date:	06/01/1979
From:	NORTHERN STATES POWER CO.
To:
Shared Package
ML19259C235	List: ML19259C234 ML19259C239 ML19259C242
References
NUDOCS 7906140448
Download: ML19259C239 (11)

Text

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NORTHERN STATES POWER COMPANY PRAIRIE ISLAND NUCLEAR GENERATING PLANT DOCKET NOS. 50-282 LICENSE NOS. DPR-42 50-306 DPR-60 PROCESS CONTROL PROGRAM FOR WASTE SOLIDIFICATION 2279 003 4

SUBMITTED: June 1, 1979 7906140 W hi

CONTENTS SECTION PAGE 1.0 PURPOSE 1 2.0 SYSTEM DESCRIPTION 2 2.1 Waste Metering Tank 2 2.2 Cement Bin 2 2.3 Mixer / Feeder 2 2.4 Shipping Container 2 2.5 Controls 2 3.0 MATERIAL CHARACTERISTICS 3 3.1 Liquid Waste Concentrates 3 3.2 Cement 4.0 OPERATING PROCEDURES 4 5.0 PROCESS CONTROL PROGRAM 5 5.1 Definitions 5 5.2 Verification of Flow Rates 5 5.3 Concentrates Sampling 5 5.4 Preprocess Checks 5 5.5 Process Set Points 5 5.6 Verification of Solidification 5 5.7 Hand Drumming 6 2279 004 2.0-1 Solid Radwaste Flow Diagram LIST OF EFFECTIVE PAGES

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Page No. Rev No.

Cover page Original 11 Original 111 Original 1-1 Original 2-1 Original 2-2 Original 3-1 Original 4-1 Original 5-1 Original 5-2 Original 2279 005 e

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4 PURPOSE o

The purpose of this PCP is to set forth operating procedures, proc ess parameters and set points to assure that cemented rad waste is adequately solidified for shipment and disposal. ~

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2.0 SYSTEM DESCRIPTION The rad waste solidification system embodies a means of mixing liquid evaporator concentrates with cement in proper proportions to ensure solidification in containers for shipment and disposal. The Solid Rad-waste Flow Diagram is shown in Figure 2.0-1.

The solidification system was manufactured by Atcor, Inc. The system consists of the following principal components:

2.1 WASTE METERING TANK The waste metering tank is a tank of approximately 700 gal process capacity.

The tank is equipped with heaters to maintain contents in solution and is equipped with an agitator to ensure homogeneity of liquid. The tank is equipped with a positive displacement discharge pump having discharge rate variable up to 10 GPM. The pump discharges directly into the mixer feeder.

2.2 CEMENT BIN The cement bin is a bin of approx 100 cu. ft. process capacity. The bin is equipped uith a vibrating lower cone to preclude bridging of ccment and to ensure uniform flow of material having a consistent bulk density. The cement bin is fitted with a discharge auger having a discharge rate variable from 0.3 to 3.3 CFM. The auger discharges directly into the mixer / feeder.

2. 3 MIXER / FEEDER The mixer / feeder is a double enveloping screw type mixer which simul-taneously blends the liquid waste and cement while conveying the mass to the discharge chute. The discharge chute directs the blended mass into the shipping container by gravity flow.

2.4 SHIPPING CONTAINER Shipping containers are standard 55 gal steel drums which are fitted with covers and clamp rings after solidification.

. 2.5 CONTROLS Controls for the solidification system are contained on a panel shielded from the waste materials.

Gages indicating feed rate of cement and waste liquid are located on the control panel.

Rates of cement feed and liquid feed are adjustable from the control panel during processing. 2279 00'7 2-1

EVAPORATOR n

WASTE CONCENTRATE TAh%

CEMENT g

BIN WASTE METERING TANK 1

o i MIXER / FEEDER 1

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2279 008 SOLID RADWASTE FLOW DIAGRAM FIGURE 2.0-1 2-2

3.0 MATERIAL CHARACTERISTICS 3.1 Liquid Waste Concentrates:

Typical analysis - Boric Acid - 12% by Wt.

Temperature - Approx 160*F 3.2 Cement Type "M" masonry cement having 50% lime and 50% portland cement, conforming to ASTM-C-91-64 and ASTM-C-270-61T.

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4.0 OPERATING PROCEDURES Operr. ting Procedures are as provided in the Operations Manual.

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5.0 PROCESS CONTROL PROGRAM

5.1 DEFINITIONS

5.1.1 BATCH

A quantity of evaporator concentrates in the waste concentrates tank preceeding the initiation of the solidifi-cation process.

5.1.2 BATCH OF CEMENTED PRODUCT: The quantity of cemented product produced from a bntch of evaporated concentrates.

5.1.3 SOLIDIFICATION

The composite physical property of cemented product that is non-plastic and free standing.

5.2 VERIFICATION OF FLOW RATES At least af ter every tenth batch of cemented product has been processed, liquid and cement flow rates are to be measured and compared with gage indications. Correction constants are to be developed as required.

5.3 CONCENTRATES SAMPLING Solutions having Boric Acid concentrations from 0% to 25% by Wt have been found to solidify using the liquid / cement ratio described under " Process Set Points". Sampling of liquid waste prior to solidification is therefore not required.

5.4 IREPROCESS CHECKS 5.4.1 Verify that the flow rates of cement and waste liquid have been calibrated within the prescribed period.

5.4.2 Verify that the system is operational.

5.5 PROCESS SET POINTS Mix ratio shall be in the following proportion:

Cement 0.8 CFM Waste Liquid 5.0 to 7.0 GPM 5.6 VERIFICATION OF SOLIDIFICATION Inspect representative barrels of each batch to verify solidification prior to capping and removal from drum storage room.

In the event that solidification does not occur, the solidification process shall be suspended until the cause is determined and corrections are made.

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5.7 IL\ND DRUFOIING

• Solidification af miscellaneous, non oil bearing, materials of low activit,, may be eixed with cement by hand in 55 gal drums using the same r.1x ratios as for evaporator concentrates.

Verification of solidification of each drum will be made prior to capping.

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PRAIRIEISLAND NUCLEAR GENERATING PLANT Red Wing, Minnesota UNITS 1 AND 2

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'1 OFFSITE DOSE CALCULATION MANUAL DOCKET NO. 50-282 AND 50-308 NORTHERN STATES POWER COMPANY MINNEAPOLIS. MINNESOTA