WATER CONSERVATION AND REUSE CASE STUDY IN ......WATER CONSERVATION AND REUSE CASE STUDY IN PHARMACEUTICAL INDUSTRY Joseph G. Cleary, P.E., BCEE HydroQual, Inc. 1200 MacArthur Blvd

WATER CONSERVATION AND REUSE CASE STUDY IN PHARMACEUTICAL INDUSTRY

Joseph G. Cleary, P.E., BCEE

HydroQual, Inc. 1200 MacArthur Blvd.

Mahwah, NJ 07430 ABSTRACT A pharmaceutical company in Puerto Rico was facing some uncertainty in the sustainability of its water supply for new drug products. The plant relies primarily on the Puerto Rico Aqueduct and Sewer Authority (PRASA) water supply for an average of 134,000 gallons per day. Groundwater was impacted by saltwater intrusion and adjacent property contamination. The company wanted to develop a water management plan to reduce reliance on the PRASA water supply in this highly developed industrial/commercial area. A water conservation and reuse study was conducted using a collaborative approach and project team. A study approach was developed and utilized to develop a site-wide water balance which was used to evaluate several alternatives to conserve and reused water. A recommended phase was developed to reduce reliance on the PRASA water supply by 80 percent and achieve the sustainability goals and objectives. KEYWORDS water conservation, water reuse, stormwater, cooling water, active pharmaceutical ingredients, wastewater INTRODUCTION This pharmaceutical company (Company A) is located in northeast Puerto Rico. The plant presently uses surface water (with the option to use groundwater) for the manufacture of pharmaceutical products. Company A was facing some uncertainty in the sustainability of both the Puerto Rico Aqueduct and Sewerage Authority (PRASA) surface water supply and the site and local groundwater supply. This uncertainty presented a risk to the production of products at Company A. A groundwater modeling study concluded that additional groundwater supply at the site may be limited due to salt water intrusion. Company A wanted to develop a site water balance and evaluate water conservation and reuse alternatives to reduce reliance on the PRASA surface water supply. The following summarizes the project drivers and background information.

Average water usage is 134,000 gallons per day from PRASA Water supply from surface water and groundwater is limited in the area

Average rainfall is 80 inches per year

“Sustainability” goal for production

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Copyright 2006 Water Environment Foundation. All Rights Reserved©

Overall goal was less reliance on public water supply

Existing wastewater plant discharges to POTW

Alternatives were needed for water conservation and reuse GOALS AND OBJECTIVES This project had the following goals and objectives:

Develop a Sustainability Plan to supply water to the site for two weeks in the event of supply problems.

Develop a site water balance for current and future water demands at the site.

Develop water conservation and reuse alternatives that are cost effective and also meet

effluent permit limits.

Reduce reliance in PRASA water supply. STUDY APPROACH The following sequence of work tasks was utilized:

Send questionnaire to plant

Review background information and data

Conduct on-site survey to work with plant personnel (three days)

Develop a site-wide water balance

Fill in data gaps with flow monitoring and sampling of key water and wastewater streams

Develop alternative evaluation criteria with plant personnel

Screen alternatives with plant personnel during survey

Identify alternatives for conceptual design and cost estimates

Develop recommendations The following information was provided to the project team prior to and during the kick-off meeting:

Groundwater modeling report status Current water balance information

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Current and future water usage data and projections

Overall site plan, area maps, and aerial photos

Water storage and consumption information

Status of PRASA Water Treatment Supply and Treatment Plant A review of the facility and key water supply and user facilities was conducted first to prioritize with client for the site survey. During and after the site visit, the project team worked with plant staff to develop an updated list of data gaps and information needs, questions, and action items requiring input from the team. The Project Director and Project Engineer visited the plant over a three day period to conduct a site survey of the facility and interview plant personnel. A survey questionnaire was filled out prior to and during the site visit. The following tasks were included within the scope of this task:

Review and refine the current and future water balance. Survey existing water uses at the facility.

Identify potential water conservation and reuse projects which may have been identified

before plus others identified by the project team.

Evaluate water make up system including cooling tower and boiler.

Evaluate potential use of surface water collected in stormwater basin.

Evaluate potential reuse of blow downs from cooling tower and other sources.

Identify potential reuse alternative for wastewater effluent. During the site visit, the team met with a number of key plant staff to fill in data gaps and discuss potential water conservation and reuse projects as well as PRASA and groundwater supplies. Wrap up meetings were conducted on each day of the site visit to digest the information collected and gather input from key project personnel. Preliminary findings were presented at the end of the three days. Outstanding issues and data gaps were addressed during follow-up conference calls. EVALUATION CRITERIA The alternatives evaluation was developed based on the following:

The current water usage at the facility was estimated to be about 134,000 gallons per day. The major water usage groups include utilities/cooling tower operations, process water usage, sanitary/cafeteria and miscellaneous usage.

Production of a new product is anticipated to increase over the next few years from the

present level of 29 percent to 95 percent by 2008.

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The impact of water reuse alternatives on wastewater treatment operations and regulatory

compliance were taken into account during the evaluation process. This is especially important when considering the discharge of active pharmaceutical ingredients (APIs) from the facility.

As part of an operating strategy/emergency management plan, Company A wanted to

have the capacity to continue production operations for a period of two weeks at the site in the event that either energy or water supplies are disrupted.

The following key evaluation criteria were developed with plant personnel:

Capital and O&M costs

Technologies common to multiple locations

User water quality needs

Sanitation and safety requirements

Impact on effluent compliance (e.g., TDS, active pharmaceutical ingredients, etc.)

Acceptance by plant staff

Potential impacts to facilities businesses operations (e.g., shutdowns for maintenance)

Contingency water storage requirements (i.e., 14 days) WATER BALANCE A site wide water balance shown in Figure 1, was conducted to develop an understanding of water usage and water quality at various stages and around various water usage groups. There are two PRASA water intakes at the facility. Based on available data in early 2004, it was estimated that the average intake is about 123,000 gallons per day. The total water usage at the facility will increase as production is ramped up over the next few quarters. The expected maximum usage of water from PRASA is about 236,000 gallons per day.

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Water usage at Company A’s facility can be broadly categorized into four groups based on usage category and water quality requirements. The percentage distribution of water consumption is shown in Figure 2.

Water usage in cooling towers/utilities represents the single largest water usage group accounting for 65 percent of the total water usage at the facility. Utilities water usage is expected to continue to remain the largest water usage group in the future (at full production capacity). Process water usage is presently at about 25 percent of the total water usage, but is likely to increase as production reaches full capacity. Sanitary usage is expected to remain constant at about 5,500 gallons per day.

Figure 1. Water Usage

Figure 2. Water Usage

Figure 1. Water Balance

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The main water usage groups include: Utilities/Cooling Tower Water Usage – Cooling towers are the single largest users of water at the Company A facility. Based on a water balance analysis performed using available plant data and a GE-Betz model (CycleOps, 4 Cycles), it is estimated that the daily maximum make up water requirement for the three cooling towers at the facility is 134,000 gallons. Process Water Usage – Process water usage at Company A’s facility is primarily in the form of USP water that is produced at various production locations. Pretreated PRASA water is further treated to meet USP water quality criteria (conductivity ≤ 1 µmhos; resistivity ≥ 1 MΩ) using multimedia filtration, activated carbon treatment, reverse osmosis and electro deionization. Typically USP water is used for clean-in-place (CIP) operations for various operations including dry-milling, dispensing, coating, etc. Water use in these operations is highly production campaign dependent, and can change frequently based on market demand for finished product. During normal operations USP water is produced only on demand from the point of use storage tanks. However, the reverse osmosis system operates continuously either in production or recycle mode, which generates a constant reject stream of about 10,000 gallons per day (nominal usage when idling). Based on a mass balance conducted with available data for 2004, it is estimated that the average process water usage is about 12,000 gallons per day. Sanitary/Cafeteria Water Usage – Water for sanitary and cafeteria usage is estimated to be about 8,000 gallons per day at Company A’s facility. It is estimated that about 5,500 gallons per day of water is obtained for sanitary and cafeteria use. Other miscellaneous activities, such as irrigation, housekeeping, etc., account for less than 1,000 gallons per day. A summary of the water quality sampling results for the various water sources and water users at the facility is shown in Table 1. The concept of “water pinch” analysis were used in identifying water reuse alternatives based on “user” water requirements and the water quality sampling data. ALTERNATIVE ANALYSIS Alternatives evaluated are described below. A comparison of the alternative capital and O&M costs is shown in Table 2. Alternative 1 In this alternative stormwater/groundwater reject from the USP water treatment system and AHU condensate is blended with fresh water (from PRASA) to reduce fresh water consumption. Existing cooling tower operating conditions are retained at 4 cycles with a blow down conductivity set point of about 1,280 mhos/cm. The concept is shown schematically in Figure 3.

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FLOW KEY PARAMETERS TYPE gallons/day TDS

mg/L Conductivity

µmhos/ Hardness

mg/L Silica mg/L

PRASA 1 Existing Source 31,000 157 274 84 24.40 PRASA 2 Existing Source 92,000 157 274 84 24.40 Well Water Existing Source 50,000 198 317 60 21.40 Stormwater Potential Source 55,000 176 295 68 5.57 R.O. Reject (USP) Potential Source 10,000 388 569 4 32.80 AHU Condensate Potential Source 8,000 9 28 4 <0.10 CT Blow down (R.O.) Potential Source 26,000 <100 <150 ND <0.10 Utilities/CT Usage 134,000 157 274 84 24.40 Process Usage 11,000 - 125 - - Sanitary Usage 2,000 157 274 84 24.40 Miscellaneous Usage 1,000 157 274 84 24.40

Table 1. Water Quality Summary

Figure 3. Alternative 1 - Existing CT Operating Conditions with Stormwater/Groundwater Supplement & AHU Condensate (4 Cycles)

PRASA

Wastewater Treatment

Mak

eup

Wat

e r

134,

000

gpd

62,000 gpd

39,000 gpd

33,000 gpd

17,000 gpd

12,000 gpd

10,000 gpd

39,000 gpd

Cooling Tower 3

Cooling Tower 2

Cooling Tower 1

AHU Condensate

8,00

0 gp

d

Stormwater / Groundwater

50,0

00 g

pd

66,0

00 g

pd

R.O. Reject USP

10,0

00 g

pd

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Alternative PRASA Water Usage

Reduction in PRASA

Water Usage

Contingency Storage

(14 days) Water Sources Cost

*Utility

Operations Only

Groundwater Stormwater2 AHU Condensate

Treated CT

Blow Down

R.O. Reject From USP

Capital2 Annual O&M

Existing 134,000 - 2.0MG - - - - - 4,160,000 24,000

Alternative 1 66,000 50% 1.0MG 50,000 55,000 8,000 - 10,000 2,950,000 87,000

Alternative 2 46,000 65% 0.65MG 50,000 55,000 8,000 - 10,000 2,165,000 82,000

Alternative 3 40,000 70% 0.56MG 50,000 55,000 8,000 26,000 10,000 1,975,000 116,000

Alternative 4 25,000 80% 0.35MG 50,000 55,000 8,000 13,000 10,000 1,675,000 115,000 1 - Utilities / Cooling Tower Operations, gallons/day 2 - Average daily flow – may not be available at all times 3 - Includes contingency storage tank cost It is estimated that about 134,000 gallons of make up water is required each day for the cooling towers under existing cooling tower operating conditions. At the present time the entire make up water is drawn from PRASA as shown in Figure 4. There is potential for reuse of 8,000 gpd of AHU condensate, 10,000 gpd of reject from the USP water treatment system and 50,000 gpd of stormwater/groundwater to supplement intake of fresh water from PRASA. Water quality characterization data for the AHU condensate and stormwater/groundwater indicate that these sources have the potential to provide high quality water with minimal pretreatment. Water analysis data was developed for all the streams considered in this study as shown previously in Table 1.

Table 2. Cost Comparison

Figure 4. Alternative 2-Optimized CT Operating Conditions with stormwater/groundwater supplement & AHU Condensate (6.5 Cycles)

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The capital cost of implementing this alternative is estimated to be about $2,850,000 which includes the cost for providing 14-day contingency storage (1 million gallons) for sustaining utility operations during any disruption of PRASA water supply. The annual O&M cost for this alternative is estimated to be about $85,000. The key advantages of this alternative include:

Existing cooling tower operating conditions are retained. Reuse of AHU condensate and stormwater/groundwater.

Reuse option results in a 50% reduction in PRASA water usage. The overall water usage

for cooling tower operations remains unchanged at 134,000 gpd.

Both AHU condensate and stormwater sources provide higher quality water for cooling tower operations than that available from PRASA. Supplementing PRASA water with either of these sources can potentially increase the number of effective cycles (which is based on a conductivity set point).

Alternative 2 In this alternative stormwater/groundwater, reject from the USP water treatment system and AHU condensate is blended with fresh water (from PRASA) to reduce fresh water consumption. Conceptually this alternative is similar to Alternative 1, except that the existing cooling tower operating conditions are optimized for 6.5 cycles. The concept is shown schematically in Figure 4. It is estimated that about 114,000 gallons of make up water will be required each day for the cooling towers when they are operated optimally at 6.5 cycles. As discussed in Alternative 1, there is a potential for reuse of 8,000 gpd of AHU condensate, 10,000 gpd of reject from the USP water treatment system and 50,000 gpd of stormwater/groundwater to supplement intake of fresh water from PRASA. Water quality characterization data for the AHU condensate and stormwater/groundwater indicate that these sources have the potential to provide high quality water with minimal pretreatment. The capital cost of implementing this alternative is estimated to be about $2,000,000 which includes the cost for providing 14-day contingency storage (0.65 million gallons) for sustaining utility operations during any disruption of PRASA water supply. The annual O&M cost for this alternative is estimated to be about $80,000. The key advantages of this alternative include:

Existing cooling tower operating conditions are optimized for 6.5 cycles. Optimization would primarily include pH control of cooling tower recycle water with sulfuric acid.

Optimization of cooling tower cycles will reduce make up water usage by 15% when

compared to existing water usage at 4 cycles.

Reuse of AHU condensate and stormwater/groundwater.

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Reuse option when combined with optimized cooling tower operation results in a 65% reduction in PRASA water usage. Overall cooling tower water usage is 114,000 gpd compared to 134,000 gpd (Alternative 1).

Both AHU condensate and stormwater sources provide higher quality water for cooling

tower operations than that available from PRASA. Supplementing PRASA water with either of these sources can potentially increase the number of effective cycles (which is based on a conductivity set point) resulting in lower water demand.

Alternative 3 In this alternative a Reverse Osmosis system is proposed for the treatment of cooling tower blow down as well as blending stormwater/groundwater, reject from the USP water treatment system and AHU condensate with fresh water (from PRASA) to reduce fresh water consumption. Existing cooling tower operating conditions are retained at 4 cycles with a blow down conductivity se point of about 1,280 μmhos/cm. The concept is shown schematically in Figure 5.

It is estimated that about 134,000 gallons of make up water is required each day for the cooling towers under existing cooling tower operating conditions. There is a potential for reuse of 8,000 gpd of AHU condensate, 10,000 gpd of reject from the USP water treatment system and 50,000 gpd of stormwater/groundwater to supplement intake of fresh water from PRASA. Additionally about 26,000 gpd of R.O. treated water is available for reuse as make up water for cooling tower operations. Water quality characterization data for the AHU condensate and stormwater/ groundwater indicate that these sources have the potential to provide high quality water with minimal pretreatment.

Figure 5. Alternative 3 – Existing CT Operating Conditions with stormwater/groundwater supplement & AHU Condensate & R.O. Treatment of CT Blowdown (4 Cycles)

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The capital cost of implementing this alternative is estimated to be about $1,875,000 which includes the cost for providing 14-day contingency storage (0.56 million gallons) for sustaining utility operations during any disruption of PRASA water supply. The annual O&M cost for this alternative is estimated to be about $115,000. The key advantages of this alternative include:

Existing cooling tower operating conditions are retained. R.O. treatment of cooling tower blow down can potentially yield 26,000 gpd of high

quality water for reuse.

Reuse of AHU condensate and stormwater/groundwater. Reuse option results in a 70% reduction in PRASA water usage. The overall water usage

for cooling tower operations remains unchanged at 134,000 gpd.

The blow down stream after R.O. treatment, the AHU condensate stream and stormwater sources provide higher quality water for cooling tower operations than that available from PRASA. Supplementing PRASA water with any of these sources can potentially increase the number of effective cycles (which is based on a conductivity set point) resulting in lower water demand.

This alternative when compared to other alternative evaluated offers a better quality make

up water since PRASA water intake is significantly reduced and at the same time a large stream of R.O. treated water is supplemented.

Alternative 4 In this alternative a Reverse Osmosis system is proposed for the treatment of cooling tower blow down as well as blending stormwater/groundwater, reject from the USP water treatment system and AHU condensate with fresh water (from PRASA) to reduce fresh water consumption. Conceptually this alternative is similar to Alternative 3, except that the existing cooling tower operating conditions are optimized for 6.5 cycles. The concept is shown schematically in Figure 6.

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It is estimated that about 134,000 gallons of make up water is required each day for the cooling towers under existing cooling tower operating conditions. At the present time the entire make up water is drawn from PRASA as shown in Figure 3. There is a potential for reuse of 8,000 gpd of AHU condensate, 10,000 gpd of reject from the USP water treatment system and 50,000 gpd of stormwater/groundwater to supplement intake of fresh water from PRASA. Additionally about 26,000 gpd of R.O. treated water is available for reuse as make up water for cooling tower operations. Water quality characterization data for the AHU condensate and stormwater/ groundwater indicate that these sources have the potential to provide high quality water with minimal pretreatment. The capital cost of implementing this alternative is estimated to be about $1,560,000 which includes the cost for providing 14-day contingency storage (0.35 million gallons) for sustaining utility operations during any disruption of PRASA water supply. The annual O&M cost for this alternative is estimated to be about $115,000. The key advantages of this alternative include:

Existing cooling tower operating conditions are retained. R.O. treatment of cooling tower blow down can potentially yield 13,000 gpd of high

quality water for reuse.

Reuse of AHU condensate and stormwater/groundwater.

Optimization of cooling tower cycles will reduce make up water usage by 15% when compared to existing water usage a 4 cycles.

Reuse option when combined with optimized cooling tower operations results in a 80%

reduction in PRASA water usage. Overall cooling tower water usage is 114,000 gpd compared to 134,000 gpd (Alternative 1).

Figure 6. Alternative 4 – Existing CT Operating Conditions with stormwater/groundwater supplement & AHU Condensate & R.O. Treatment of CT Blowdown (6.5 Cycles)

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The blow down stream after R.O. treatment, the AHU condensate stream and stormwater sources provide higher quality water for cooling tower operations than that available from PRASA. Supplementing PRASA water with any of these sources can potentially increase the number of effective cycles (which is based on a conductivity set point).

This alternative offers a good quality make up water since PRASA water intake in

significantly reduced and at the same time a large stream of R.O. treated water is supplemented.

RECOMMENDED ALTERNATIVE Alternative 4 was selected by the projet team to reduce reliance of PRASA water use to 25,000 gpd or 80% reduction by using air handling condensate, groundwater or stormwater and RO reject water. Figure 7 shows the proposed layout for this alternative.

PHARMACEUTICAL ACTIVE INGREDIENTS (APIs) There were two pharmaceutical active ingredients (APIs) which were evaluated for compliance. Based on the Company’s API Effluent Management Philosophy, the maximum possible loss of the two compounds from the facility were estimated to be 3 kg/day and 5.9 kg/day, respectively. A holding and equalization system was designed to ensure corporate receiving water concentration guideline in the ocean were achieved. The volume of effluent that the facility

Figure 7. Proposed Layout of Water Reuse

STORM WATER (Existing Collection System)

Well Water

EXISTING STORM WATER COLLECTION BASIN

UTILITY MAKEUP WATER

50,000 gpd (35 gpm on demand)

over

flow

outfall

50,000GALLON

TANK(Existing)

STORM WATER (New Connection)

CONTINGENCYSTORAGE *

PRASAON DEMAND

55,000 gpd

Water Treatment(Existing)

AHU CONDENSATE8,000 gpd TREATED CT BLOWDOWN

R.O. REJECT FROM USP 10,000 gpd

* Contingency StorageCapacity (14 days)

Alternative 1 – 1.00 MGAlternative 2 – 0.65 MGAlternative 3 – 0.56MGAlternative 4 – 0.35 MG

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discharges to PRASA did not have any impact on the manner in which the discharge of two compounds are presently managed as per the Effluent Management Philosophy. Therefore, reduction in the volume of influent to the wastewater treatment system due to water recycling and other water conservation efforts had no impact on the mass of compound that may be discharged from the facility. CONCLUSIONS The following conclusions were made from the study:

Existing water usage at the Company A facility is 134,000 gallons per day, which is entirely obtained from two intakes.

Utilities/cooling tower operations represent the single largest user group and accounts for

greater than 65 percent of water usage at the facility.

Process water usage accounts for 25 percent of the water usage at the facility.

Cooling tower blow down is estimated to be about 39,000 gallons per day at four cycles. Blow downs are controlled by a conductivity set point of 1,280 µmhos/cm.

Stormwater is collected in a stormwater collection basin. It is estimated that an average

of 55,000 gallons of stormwater is discharged from the site each day.

Implementation of a water conservation and reuse plan will have no adverse impact on effluent management program for APIs.

Additional storage capacity is needed to sustain utility operations for 14 days if PRASA

water supply is disrupted. RECOMMENDATIONS

Installation of a utilities water storage tank

Collection of air handling condensate and reverse osmosis (RO) reject

Reduction of the cooling tower’s water demand by increasing cycles of concentration and reusing part of the blowdowns

Collection of stormwater for make-up utilities water

Continue to evaluate the feasibility of using the well water supply and new well field

SUMMARY

The study approach was successful. Most plants need update of water balance as well as user water quality data.

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Consultant working with plant personnel is critical to project success.

Plant is implementing design/construction of the recommended facilities.

The recommended reduced reliance on PRASA water by over 80% met sustainability goal.

ACKNOWLEDGEMENTS The author would like to acknowledge Dr. Sudhi Mukherjee of the World Bank International Finance Corporation in Washington, D.C. and Brown and Caldwell, Inc. The author and Dr. Mukherjee completed this project in 2004 when both were working for Brown and Caldwell, Inc.

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Documents

WATER CONSERVATION AND REUSE CASE STUDY IN ......WATER CONSERVATION AND REUSE CASE STUDY IN PHARMACEUTICAL INDUSTRY Joseph G. Cleary, P.E., BCEE HydroQual, Inc. 1200 MacArthur Blvd