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NEA-1345 HARPHRQ

HARPHRQ, Geochemical Reaction Modelling

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1. NAME OR DESIGNATION OF PROGRAM:  HARPHRQ.
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2. COMPUTERS
To submit a request, click below on the link of the version you wish to order. Only liaison officers are authorised to submit online requests. Rules for requesters are available here.
Program name Package id Status Status date
HARPHRQ NEA-1345/01 Tested 06-JAN-1994

Machines used:

Package ID Orig. computer Test computer
NEA-1345/01 IBM PC PC-80486
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3. DESCRIPTION OF PROGRAM OR FUNCTION

HARPHRQ is a program based on the code PHREEQE and is designed to model geochemical reactions. Like PHREEQE, it can calculate the pH, redox potential and mass transfer as a function of reaction progress and the composition of solution in equilibrium with multiple phases. In addition, HARPHRQ includes options to allow the composition of a solution at a fixed pH to be calculated and to automatically add or remove mineral phases as they become saturated or exhausted. A separate module can  also be interfaced to give a choice of sorption models including the triple-layer model.
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4. METHOD OF SOLUTION

The code solves a reduced set of simultaneous non-linear equations. The conceptual model embodied in PHREEQE and HARPHRQ is the ion-association model of Pearson and Noronha to obtain values for a set of key independent variables. These results  are then used to solve for all other unknowns sought. The key independent variables in PHREEQE are:
     1. aH+ the activity of the hydrogen ion in solution;
     2. ae- the activity of the electron in solution;
3. the activity of a single aqueous (master) species for each element;
4. the amount of mass transferred between each mineral phase and solution to achieve equilibrium.
From these data, the code calculates the dependent variables, including activities of all other aqueous species specified. The equations used to solve for key independent variables are:
     1. Electrical neutrality;
     2. Electron balance;
     3. Mass balance;
     4. Mineral equilibrium.
Where a constant pH is to be maintained, the electrical neutrality equation is removed from the refinement procedure in HARPHRQ. The equations are solved using:
     1. a continued-fraction approach for the mass-balance equations; and
     2. a modified Newton-Raphson approach for the remaining equations.
The activity coefficient can be calculated in HARPHRQ using the Debye-Huckel and Davies corrections from PHREEQE, and also a modified Davies correction. The modified Davies option uses the Davies expression up to ionic strength 0.3 mol dm-3 and then maintains the magnitude of this correction at ionic strengths above  the cut-off value.
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5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

The conceptual and numerical limitations of PHREEQE are also applicable to HARPHRQ. In  addition, it should be noted that if the pH is fixed the resulting solution will not be charge balanced. The selection of the pH-fix option in HARPHRQ limits the number of types of reaction that can be modelled. For example, if a second solution is defined for mixing with the initial solution they should have the same pH. Similarly, a titration with either protons or hydroxide ions is not possible. However, a stepped pH, pe or both pH and pe have been included to simulate a titration with protons or hydroxide ions, or other similar experiments. These restrictions only apply when the option for calculating a solution at fixed pH is chosen.
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6. TYPICAL RUNNING TIME

The typical run times for HARPHRQ are similar to those for PHREEQE.
NEA-1345/01
The six test cases included in this package were run by the NEA-DB on a PC/80486 with 66 MHz. Running times were in the range between a tenth of a second and 1.3 seconds.
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7. UNUSUAL FEATURES OF THE PROGRAM

It is possible to interface HARPHRQ with a module that allows modelling of adsorption reactions  using models such as the triple-layer model. (This module is not available from the NEA, please contact authors for further information.)
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8. RELATED AND AUXILIARY PROGRAMS

The program PICKER enables HARPHRQ  to be used in conjunction with the HATCHES database by selecting a
problem-related database from the much larger, fully documented HATCHES management system.
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9. STATUS
Package ID Status date Status
NEA-1345/01 06-JAN-1994 Tested at NEADB
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10. REFERENCES

- P.L. Brown, A. Haworth, S.M. Sharland and C.J. Tweed,
  HARPHRQ: A geochemical speciation program based on PHREEQE.
  Nirex Safety Studies Report NSS R.188 (to be published 1991).
- C.J. Tweed,
  A guide to PICKER - A Data Selection Program for the Geochemical
  Code PHREEQE
  Nirex Safety Studies Report NSS R.132 (1988).
NEA-1345/01, included references:
- NEA Data Bank:
  Note to Users of HARPHRQ (NEA 1345/01)
  (June 1990)
- P.L. Brown et al.:
  HARPHRQ - A Geochemical Speciation Program Based on PHREEQE
  User's Guide
  (October 1991).
- D.L. Parkhurst, D.C. Thorstenson and L.N. Plummer:
  PHREEQE - A Computer Program for Geochemical Calculations.
  USGS/WRI-80-96  (Rev. January 1985)
- G.W. Fleming and L.N. Plummer:
  PHRQINPT - An Interactive Computer Program for Constructing Input
  Data Sets to the Geochemical Simulation Program PHREEQE
  USGS/WRI-83-4236  (1983)
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11. MACHINE REQUIREMENTS

540K bytes storage.
NEA 1345/01: The test cases included in this package have been executed by NEA-DB on a DELL 466/L 66-MHZ PC/80486 desktop computer.
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12. PROGRAMMING LANGUAGE(S) USED
Package ID Computer language
NEA-1345/01 FORTRAN-77
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13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  DOS (IBM PC), AIX
NEA-1345/01
The program was tested at NEA-DB under MS-DOS 6.0 using the Lahey F77L-EM32 FORTRAN-77 version 5.11 compiler.
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14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

HARPHRQ generally meets ANSI standards for Fortran. No problems have been encountered by the authors in porting the code, but extensive testing has not been carried out. See the PHREEQE entry for further  information.
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15. NAME AND ESTABLISHMENT OF AUTHORS

      A. Haworth, C.J. Tweed and S.M. Sharland
      AEA Decommissioning and Radwaste
      Harwell Laboratory
      Oxon OX11 ORA
      UNITED KINGDOM
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16. MATERIAL AVAILABLE
NEA-1345/01
File name File description Records
NEA1345_01.001 HARPHRQ Information File 330
NEA1345_01.002 HARPHRQ Source Code File 3281
NEA1345_01.003 HARPHRQ PC-executable code 0
NEA1345_01.004 UO2 Dissolution - Input Test sample 15
NEA1345_01.005 UO2 Dissolution - Output data file 1390
NEA1345_01.006 Library data for a set of uranium minerals 288
NEA1345_01.007 Iron dissolution - Fix PH test sample 10
NEA1345_01.008 Iron dissolution - Fix PH output data file 152
NEA1345_01.009 Iron dissolution - Floating PH test sample 10
NEA1345_01.010 Iron dissolution - Floating PH output data 152
NEA1345_01.011 Iron dissolution-Finite minerals test sample 16
NEA1345_01.012 Iron dissolution-Finite minerals output data 1003
NEA1345_01.013 Fe01 test case 14
NEA1345_01.014 Fe01 output data file 161
NEA1345_01.015 Fe002 Test case 16
NEA1345_01.016 Fe002 Output data file 429
NEA1345_01.017 Library data to run the Iron Test samples 88
NEA1345_01.018 PHRQINH Source Code File 2801
NEA1345_01.019 PHRQINH PC-executable code 0
NEA1345_01.020 Thermodynamic library (PHRQINH input data) 579
NEA1345_01.021 Library of Minerals (PHRQINH input data) 82
NEA1345_01.022 DOS file-names 21
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17. CATEGORIES
  • R. Environmental and Earth Sciences

Keywords: aqueous solutions, chemical reactions, geochemistry, geothermal, ground water, mass transfer, solubility, sorption.