^ Water and wastewater

Article by Robert McIlvaine, President & Founder, The McIlvaine Company

Municipal and industrial markets

Municipalities and investor owned utilities account for approximately 18% of worldwide equipment and piping purchases, where stainless steel is a main material of construction. Process applications account for 45% of this revenue.

The industrial sector spends 37% of total equipment purchases on its water and wastewater applications. For stainless steel manufacturers who are already providing materials for pumps and valves in the industrial water and wastewater market, there are many similar applications found in the municipal sectors.

Treatment processes within municipal wastewater plants typically utilize filter presses, belt presses, and centrifuges for dewatering. Large quantities of stainless steel are used in centrifuges, making these rotating devices weigh several tons. Table 1 shows the multiple uses of stainless steel in a manufacturer’s centrifuges.

In the industrial sector, the same equipment, utilizing stainless steel materials, is used for dewatering in mining, steel, food, and chemical processing applications. In fact, in many cases industrial plants must decide whether to discharge wastewater into the sewer and pay substantial sums to municipalities, or to install the equipment themselves. Some large wastewater utilities such as the Chicago Water Reclamation District seek out sewage from food plants in order to make biogas from the sewage. Stainless steel components are found in this conversion process.

A number of large food processors are doing the opposite. They own the municipal treatment plants in small rural towns and treat the city sewage as well as their own waste. They frequently convert the sewage to usable biogas for onsite power. As a result, these food companies are not only using stainless steels in the production of food products, but also in wastewater treatment.

Table 1. An example of the uses of stainless steel in Flottweg SE centrifuges.

 Stainlees steels   Componentes of decanter
 Austenite  Housing and other parts of decanter in contact with the product
 Duplex  Rotating parts, e. g. drum body
 Nickel-base alloy  Drumm body, screws (Hastelloy for corrosive media)

Global initiatives
The market for stainless steels in water and wastewater applications has been negatively impacted by the coronavirus. There have been some temporary shifts as residential water use has increased, while industrial and commercial use has decreased. Utilities in the United States have lost revenues due to the nonpayment of fees by those in financial distress, and there have also been some postponement of projects.
President-elect Joe Biden has rolled out a variety of clean energy and infrastructure plans. He recently unveiled a four-year, USD $2 trillion plan to reinvigorate the U.S. economy by investing in infrastructure. As it relates to water utilities, Biden’s plans focus on investing in water infrastructure and addressing drinking water contaminants.
As COVID-19 spread across the globe, the consequences of chronic underinvestment in water and sanitation services for billions of people are becoming abundantly clear. Right now, the global focus is on helping families to survive the pandemic, but the United Nations advises that even as we get on top of the pandemic and save as many lives as possible, we need to build resilience for the future. Without action, the world remains vulnerable to a range of growing threats:
  • Global demand for water is sky rocketing, while many water sources are becoming more polluted.
  • Agriculture is getting thirstier, as is industry, manufacturing, and energy generation.
  • Climate change is making water scarcer and more unpredictable, displacing millions of people.
The United Nations Secretary General has called for a comprehensive multilateral response, amounting to a double-digit percentage of global gross domestic product (GDP). This is intended to address the financial shock of the recession. The economic case for investments in drinking water, sanitation and hygiene services is clear. In urban areas, every U.S. dollar (USD) invested in basic sanitation returns USD $2.5 in saved medical costs and increased productivity. For drinking water, the average return is USD $3.0.
In some areas, such as a large portion of Africa, it will be a challenge to provide adequate funding. In water scarce areas, desalination will be highly desirable but also quite expensive. China has invested in desalination in a big way. The value of this investment is proven in Israel where desalination supplies nearly all the water needs, and stainless steels are used throughout the desalination process.

Looking ahead
The future of the stainless steel industry is made brighter by the movements toward desalination, water reuse, and tertiary water treatment. The investment in stainless steel for drinking water from wells or lakes is small by comparison to that created by water reuse. Desalination requires a very large investment in corrosion resistant equipment and piping1.
The water and wastewater market has not had the spectacular surges that the oil and gas market has experienced. On the other hand, it has been and will continue to be a substantial and growing market for stainless steel suppliers. The rapid growth of desalination is a very positive aspect.
1. Stainless Steel Markets published by the McIlvaine Company