POWER GENERATION INDUSTRY

Project Profile

Project Description and Challenges

APS commissioned the Redhawk Power Station in 2002. The plant is comprised of

two 2x1 combined cycle natural gas-fired units to produce a total of 1060 MW of

electrical power.

Critical to the planning and

permitting of this facility was

the source and utilization of

water and the

environmental impact of

the station with respect to

liquid emissions.

Based upon these issues,

Redhawk was designed to

use reclaimed municipal

effluent from the nearby

Palo Verde Nuclear

Generating Station for its

process water requirements.

What is unique about this

source of water is that it’s

supplied by several

neighboring City of Phoenix municipal treatment facilities with their associated

seasonable variability. The plant would also be designed to utilize well water as a

contingency and achieve in either case, high-quality water for continuous re-use

throughout the plant.

The second critical aspect of the plant is the permitted requirement as a Zero

Liquid Discharge facility. Under this condition, no aqueous waste can be

discharged from site operations into the environment.

To effectively meet this requirement, the wastewater treatment system must be

designed to remove water contaminants and recycle high-quality water back into

the process. This closed loop integration of the overall water and wastewater

cycle must be achieved over the complete range of feed water conditions as well

as support the varied operating conditions of the host station.

For successful production of high purity water, maintaining cooling tower

conditions for high availability and compliance with the Zero Liquid Discharge

mandate, APS needed a total systems approach to the design of the water

treatment facility at Redhawk. HPD was chosen as the solutions provider for this

project based on their ability to execute the design, construction and project

management of the entire water treatment facility on a

design-build basis.

APS

Redhawk Power

Station

Arlington, AZ, U.S.A.

The Client

APS (Arizona Public Service) has

been a leading provider of

electricity and energy products

and services to the Western United

States for over a century.

With power plants located

throughout the Southwestern U.S.,

APS provides natural-gas, coal and

nuclear generated electrical power

to the region. HPD ZLD System
USA

23563 W. Main Street, IL Route 126

Plainfield, IL 60544

Tel.: 815-609-2000

Fax: 815-609-2044

SPAIN

Avenida de Neguri, 9 - 1 ̊

48992 Getxo

Tel.: +34 94 491 40 92

Fax: +34 41 491 11 40

www.hpdsystems.com

HPD.info@veoliawater.com

HPD-CS-REDHAWK-0208

Project Design and Technology Solutions

APS chose proven and resilient technologies to successfully achieve the

objectives of the Redhawk Power Station wastewater treatment facility. The

Zero Liquid Discharge (ZLD) System had to reclaim water resources and reject

waste properly as an integrated component of the power station. To accomplish

this, the process utilized brine evaporation and crystallization systems, which

were the key elements in the overall design.

The evaporator was designed to receive 450 gpm of high salinity blowdown

from the cooling towers. The compressor-driven evaporator pre-concentrates

the brine and produces high purity distillate for recycling to the cooling tower

and service water system.

Concentrate from the evaporator is advanced to the crystallizer where the salts

that form the impurities are crystallized and sent to a centrifuge for dewatering.

The crystallizer is also compressor-driven and produces distillate that is

combined with that of the evaporator for recycle.

The Results

The ZLD system was efficiently

completed and commissioned by

HPD in the promised time frame.

Since the startup of the integrated

ZLD system, the Redhawk Power

Station has successfully

accomplished the goal of

effectively recycling the waste

created by cooling tower

blowdown and producing highquality water while adhering to the

Zero Liquid Discharge mandate.

The Results

HPD was the sole point of

responsibility in providing a

design-build solution for the

complete wastewater portion of

the plant which included:

> All major equipment

> Mechanical erection

> Buildings

> Utility piping and valves

> Electrical hardware and cabling

> Overall control system

> Insulation and painting

> Structural support and access

steel

> Training of staff, commissioning

and start-up support

POWER GENERATION INDUSTRY

Project Profile

HPD turnkey wastewater treatment facility at Redhawk Power Station