Hydrocarbon Processing Copying and distributing are prohibited without permission of the publisher
Email a friend
  • Please enter a maximum of 5 recipients. Use ; to separate more than one email address.



Consider software tools for water reuse projects

10.01.2012  |  Huchler, L. A.,  MarTech Systems, Inc., Lawrenceville, New Jersey

Keywords: [water] [water treatment] [computer modeling] [software] [simulation] [chemical treatment] [corrosion] [utilities] [environment]

The hydrocarbon processing industry needs reliable and economic sources of water for present and future operations. Ensuring a sustainable water supply requires a focused effort to evaluate the quality and quantity of alternative water sources, reuse of individual water streams or the combined outfall stream, and/or changing regulatory requirements.

Modeling

The most common methodologies to analyze water circuits are pinch technology and mass balance/solution modeling. Application of classic pinch technology for water systems, as shown in Fig. 1, evaluates only the hydraulic demands for water. 

 

  Fig. 1. Sample water-pinch diagram.1



Better option

A better solution is to construct a sophisticated computerized model of the facility’s water systems that incorporates hydraulic information, along with ionic equilibria of soluble contaminants. Like pinch technology, this approach requires an accurate water balance.

Fig. 2 is a sample flow diagram with color-coded streams: steams—red, water—blue, recycled water—green and wastewater—brown. This approach models the ionic equilibria of the soluble contaminants, providing information about water quality for each unit operation.

 

  Fig. 2. Refinery water flow schematic.2



Modeling a water system also requires creating a “salt” or contaminant balance. The optimal approach is to profile water quality throughout the system by analyzing numerous samples at every location, and then compare the actual water quality to the predicted value in the model. When the actual water quality and flowrates closely match the predicted values, the model is considered “validated” for the present plant conditions—the baseline case.

A validated model allows the facility to hypothetically reprocess water to meet the specification limits for individual process units and to identify candidate water streams for reuse or retreatment (recycling). The model also provides insight into the hydraulic and chemical impacts on the unit and the total system balances for mass and salt concentrations.

This computerized modeling provides an accurate assessment of options: different configurations and/or operating scenarios to improve system operability, justification capital improvement projects, optimization system reliability and minimization of the risk of off-spec or lost production. Embedded within this analysis is a projection of the chemistry change for the cooling water. The only remaining analysis for this unit operation is a separate modeling task using a different software program to design an appropriate chemical-treatment program to control the corrosion, deposition and microbiological populations within the cooling water circuit.

Quality repurposing

As the quantity and quality of water decreases, industrial users will need to increase their efforts to conserve, recycle water and conform to even stricter regulatory requirements for withdrawal and discharge. Software tools can provide methods for plant personnel to quickly and economically analyze numerous system configurations providing a high level of confidence about the option that best meets their objectives.

LITERATURE CITED

1 EPRI document TA-114453, Electric Power Research Institute, Inc., 1999.
2 Data Mobility Systems, a business of Nalco, www.datamobility.com, 2011.

The author


Loraine A. Huchler is president of MarTech Systems, Inc., a consulting firm that provides technical advisory services to manage risk and optimize energy- and water-related systems including steam, cooling and wastewater in refineries and petrochemical plants. She holds a BS degree in chemical engineering, along with professional engineering licenses in New Jersey and Maryland, and is a certified management consultant.



Have your say
  • All comments are subject to editorial review.
    All fields are compulsory.

Pradeep Chatterjee
10.27.2012

From where can I buy these software.

Solimar Farrell
10.25.2012

Is there any software actually used for doing this type of analysys?

Related articles

FEATURED EVENT


Sign-up for the Free Daily HP Enewsletter!

Boxscore Database

A searchable database of project activity in the global hydrocarbon processing industry

Poll

Should the US allow exports of crude oil? (At present, US companies can export refined products derived from crude but not the raw crude itself.)


64%

36%




View previous results

Popular Searches

Please read our Term and Conditions and Privacy Policy before using the site. All material subject to strictly enforced copyright laws.
© 2014 Hydrocarbon Processing. © 2014 Gulf Publishing Company.