Customizing water efficiency solutions for industrial manufacturers

Enviro-Stewards meeting with Dextran representatives
Enviro-Stewards Inc. worked closely with Dextran Products Ltd. to identify opportunities for retrofit projects in their plant.
By Alyssa Cerbu and Eric Meliton

The manufacturing sector in Canada faces many challenges related to international competition. To remain competitive, companies must seek viable solutions while still complying with industry standards, such as Good Manufacturing Practices for food and beverage and pharmaceutical manufacturers. One such challenge is the rising costs of production due in large part to the costs of inputs, such as energy and water.

For a small to medium sized business especially, these strains can hurt profit and overall security. Therefore, it becomes more important to try to minimize costs and maximize resource productivity in a way that is feasible for the business, remains in line with their existing operations and ensures compliance with their industry’s regulations.

Partners in Project Green, a group within the Toronto and Region Conservation Authority, works with businesses in the Greater Toronto Area to help customize solutions for their various environmental challenges. It has been developing a series of capital projects to showcase best practices in water stewardship and what is feasible for any set of operations.

Partners in sustainability programming

Partners in Project Green works with the Region of Peel, York Region and City of Toronto to increase the effectiveness of existing municipal water efficiency programs. Through enrollment in these municipal programs, commercial and industrial manufacturers can obtain capital efficiency recommendations they can implement to realize savings on their utility bills. Frequently, however, businesses do not know where to start and find that water efficiency is not a concern for all internal stakeholders. Through the Innovative Water Technologies Program, member organizations can gain access to a network of experts and vendors that support the implementation of process water and wastewater efficiency technologies.

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Through a series of workshops and its municipal partnership with the City of Toronto, Partners in Project Green was put in touch with Dextran Products Ltd., which used over 13,000 m3 of water per year. As part of the vendor network, Enviro-Stewards Inc. worked closely with the company to identify opportunities for retrofit capital projects in their plant that would add up to efficient water and energy savings.

Dextran Products have been operating in their Toronto production facility for over four decades, manufacturing bulk dextran powders and liquids for sale and export through an international network of human and animal health product distributors. They are primarily used to treat anemia in pigs as well as for biological and biochemical research. Derivative applications include: adjuvants, emulsifiers, carriers and stabilizers in pharmaceutical and cosmetic preparations.

The company was paying extremely high water bills, upwards of $230,000 on average per year. Although this excessive cost was a primary motive for their capital project installation, they also wanted to promote themselves as a greener, more ethically responsible company which complied with regulations and participated in programs with the City of Toronto (i.e., Sewer Use By-Law, Industrial Water Rate and Sewer Surcharge Rebate). Through its retrofits, Dextran Products wanted to also capitalize on monetary incentives available from Partners in Project Green, as well as Enbridge, for reducing water and natural gas usage in their processes.

The installed reverse osmosis system
As part of the retrofit projects, a reverse osmosis system was installed to filter process water for reuse as scrubber make-up.

Additionally, these efforts would ensure Dextran Products were compliant with water quality pharmacopeia standards for its products around the world, thereby allowing them to ship globally.

How Dextran’s system works

According to different global pharmacopeia standards, Dextran Products, as a compliant pharmaceutical manufacturer, cannot reuse water in their product. By customizing their manufacturing process, however, they are able to reuse water in other processes within their operations (i.e., boilers, rinse systems and systems that do not require freshwater), without directly impacting the purity of the final products. They are, therefore, able to cut down on their resource use and save money while still maintaining and complying with industry and sector standards.

A customized solution to process water and wastewater challenges can really work with an organization’s existing infrastructure needs, which, in this case, involved compliance with restrictive pharmaceutical manufacturing regulations. Their intricate system went through several design phases with Enviro-Stewards Inc. and is incredibly interconnected. It is a good example to showcase that several small changes in one’s manufacturing process can equate to large, overall water and energy cost savings. Details of their overall system retrofits are provided in Table 1.

Table 1. Water and energy saving retrofits
Retrofit InstallationBeforeAfter
Temperature regulating valve for vacuum pump: The process utilizes a sludge machine that filters out iron from wastewater utilizing a vacuum pump, which requires cooling water.System did reuse some water, but a large volume of water going down the drain had additional cooling capacity.A new temperature regulating valve allows the flow to be regulated to remove only the necessary amount of heat from the vacuum pump. Cooling water is now sent to a storage tank to be reused by the scrubbers, thereby halving the amount of water going down the drain.
Connecting reactors to cooling tower: The reactor vessels are where production takes place and require cycles of heating and cooling.Municipal water went straight down the drain after cooling phase.Through connecting three reactors to the cooling tower, they will be reducing water consumption associated with cooling tower.
Cooling tower sump: Water utilized for their cooling tower.Cooling tower was using a large volume of make-up water and sump was constantly overflowing.Working to increase blowdown setpoint to reduce the volume of make-up water used by their cooling tower. Float valve was fixed to stop overflow of the cooling tower sump.
Resin regeneration: A resin tank is used in a production step that utilizes water in various stages.A lot of the water was unsuitable for reuse and sent down the drain due to its acidic or basic properties.Through installing controls and piping, acceptable water will be sent to the scrubber water make-up tank for reuse.
Condensate recovery system: Reactor vessels in the process are heated with steam that is generated in a boil and, later, condenses.Condensed water was sent to drain at each reactor.The hot, condensed water is used to preheat the make-up water for the boilers thereby reducing energy and water consumption.
Reverse osmosis system: A significant step in production process is distillation.Process water, a mixture of water and sugar, was sent to drain after distillation.A reverse osmosis system filters the water and sugar so that water can be reused as scrubber make-up and the remaining, concentrated sugar can be potentially sold.
Pump cooling: A pump in the boiler room requires water for cooling and to maintain a seal.Cooling water was going to the drain.Cooling water will be sent to the scrubber water make-up tank for reuse.

Overall, through closing these loops and adjusting their process, Dextran Products are able to save 45,450 m3 of water annually, which had an equivalent cost savings in 2016 of $109,760. They also directly benefited from an additional $10,000 worth of natural gas saving and $600 in cooling tower treatment chemicals. Should they be able to filter some of the sugar from the water, they will be able to benefit from an approximate $8,800 from the sale of concentrated fructose.

Lessons learned
Partners in Project Green and Enviro-Stewards Inc. presenting a cheque to Dextran Products Ltd. at the Water Innovation in Action 2.0 conference in October 2016.
Partners in Project Green and Enviro-Stewards Inc. presenting a cheque to Dextran Products Ltd. at the Water Innovation in Action 2.0 conference in October 2016.

Through customizing their system, Dextran Products were able to directly benefit from small process changes that had low costs and risks associated with implementation that added up to a larger water and energy cost savings impact. And, these retrofits are still in compliance with industry regulations for the pharmaceutical sector.

Partnerships were also critical to the success of this project. Partners in Project Green played an educational role to help key stakeholders at Dextran Products understand the importance of and potential results from water efficiency. Additionally, implementation of the Innovative Water Technologies project was facilitated through the support of the vendor network.

The ultimate goal is to utilize Dextran Products’ success to showcase to other manufacturers in the Greater Toronto Area that it can be beneficial to enroll in municipal water efficiency programs. Also, this project can help encourage other businesses to explore water reuse and energy efficiency improvements within their own facilities.

Process water and wastewater effluent improvements in a facility do not have to be complex and expensive to add up to large savings for an organization. Simplistic solutions to these manufacturing challenges can help organizations reduce costs, showcase their competitiveness and grow their business.

Alyssa Cerbu and Eric Meliton are with The Toronto and Region Conservation Authority. This article appears in ES&E Magazine’s February 2017 issue.


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