Lined Pipe for Data Center Water Treatment

A data center is not a chemical plant, and most of its piping is ordinary: carbon steel and copper chilled water loops, HDPE condenser water, stainless and plastic inside the liquid cooling distribution. Plastic-lined steel pipe has a real but specific job on a data center campus, and this page is about that job: the chemical feed systems that keep cooling towers clean, the reverse osmosis and demineralizer plants that make water pure enough for direct-to-chip cooling, and the on-site water treatment and reuse plants that the largest campuses build where water is scarce. Marspec Technical Products fabricates PTFE-, PVDF- and polypropylene-lined pipe spools and supplies lined fittings and valves for those systems, with spools shipped from Fairhope, Alabama. Call (251) 625-4949 or contact us online with the chemical list and line sizes.

If a mechanical contractor or water treatment integrator is reading this to decide whether lined pipe belongs on a particular line, the short version is: yes for concentrated treatment chemicals and regeneration acid and caustic, usually no for the cooling water itself. The rest of the page says why, line by line.

Where lined pipe belongs on a campus

Cooling tower chemical feed

An evaporative cooling plant concentrates whatever is in its makeup water, so it runs a treatment program: sodium hypochlorite or bromine-based oxidizing biocide for biological control, a non-oxidizing biocide on a schedule, sulfuric acid for pH and alkalinity control where the makeup water is hard, scale and corrosion inhibitors, and sometimes sodium bisulfite to dechlorinate blowdown before discharge. The bulk chemicals are delivered at strength, 12.5 percent hypochlorite and 93 percent sulfuric acid among them, and the lines from the storage tanks to the dosing skids and injection quills are where bare steel fails and PVC becomes a liability at pressure. PTFE-lined steel carries sulfuric acid, hypochlorite and bisulfite, each in a dedicated line: hypochlorite releases chlorine gas when it meets acid, and it reacts with bisulfite and gives off heat, so no header carries more than one of them. PVDF is an option on the bisulfite line, and on hypochlorite only when it is dilute or generated on site at pH 12 or below. Lined diaphragm valves throttle, lined ball valves isolate the acid and bisulfite, and hypochlorite takes lined diaphragm valves or ball valves with a vented ball (vent facing upstream). Together that gives a flanged, pressure-rated chemical feed system that survives the life of the plant. Hypochlorite decomposes and releases oxygen, so those lines are vented and laid out without dead legs.

Makeup water and reverse osmosis

Campuses in hard-water regions soften or demineralize their makeup water to run the towers at higher cycles and cut consumption. A reverse osmosis plant uses antiscalant, acid for pH adjustment ahead of the membranes, sodium bisulfite to remove chlorine, and a clean-in-place system that circulates citric acid, caustic and surfactant through the membranes on a schedule. The RO concentrate is a chloride brine that pits stainless over time. Lined pipe is specified for the acid and caustic CIP loops, the concentrated chemical feed and, in larger plants, the concentrate header to disposal or evaporation. The permeate and product water lines are usually stainless or plastic and do not need lining.

Deionized water for liquid cooling

Direct-to-chip and rear-door liquid cooling run a technology cooling system loop of treated, often deionized, water with corrosion inhibitor, and the quality of that water decides the life of the cold plates. The polishing loop and the coolant distribution units are stainless and engineered plastics, which is correct, and lined steel has no place inside them. Where lined pipe does belong is the water plant that feeds them: the mixed-bed or two-bed demineralizer regeneration systems that run hydrochloric or sulfuric acid and sodium hydroxide, the bulk acid and caustic storage and transfer, and the neutralization of spent regenerant before discharge. PTFE-lined spools and lined diaphragm valves on the regeneration side are standard water plant practice, and PTFE carries the caustic as well; polypropylene-lined pipe is available for the caustic where a specification calls for it.

Water treatment and reuse plants

The largest campuses in dry regions build their own water treatment: lime or caustic softening, ultrafiltration, RO, sometimes brine concentrators or zero-liquid-discharge evaporators, and on-site wastewater treatment with hypochlorite disinfection so blowdown can be reused rather than sent to the sewer. That is a small municipal or industrial water plant on a data center site, with the same acid, caustic, hypochlorite, ferric coagulant and brine lines a city plant has, and the same case for lined pipe on each of them. Our page on water and wastewater treatment covers the chemistry in detail.

Where it does not belong

Chilled water, condenser water and glycol loops are carbon steel, copper, HDPE or stainless, and lined pipe would add cost without benefit. Diesel fuel systems for the generators are steel. Battery rooms do not pipe electrolyte. Refrigerant lines are copper or steel. Inside the liquid cooling loop, stainless and engineered plastics are right. We would rather tell you that up front than quote a line you do not need; a lined chemical feed system is a modest package, typically 1/2 inch through 4 inch, and its value is in keeping hypochlorite off a switchgear room floor, not in its size.

What a data center package looks like

We fabricate lined pipe spools to the treatment skid drawings, 1/2 inch through 12 inch and usually 1/2 inch through 4 inch on a data center, in carbon steel housings with PTFE, PVDF or polypropylene liners chosen chemical by chemical, with lined elbows, tees and reducers to match. Lined diaphragm valves on dosing lines, lined ball valves for isolation (with a vented ball, vent facing upstream, on hypochlorite), lined check valves at injection points, lined sampling valves where the treatment program is monitored, and lined strainers ahead of metering pumps. Spectacle blinds and PTFE spacers where a chemical can be isolated for tank cleaning. Straight spools up to 20 ft, built to your isometric with flange orientation set at the shop, so the mechanical contractor bolts them up rather than fitting them. Liner limits and flange data are on our technical details page, and our lined pipe and fittings and lined valves pages show the range.

Schedule matters more on a data center than almost anywhere else we ship. Campuses are built in phases against energization dates, and the water plant is on the critical path for the first cooling tower start-up. Custom spools are what we build, and a chemical feed package can be quoted from a chemical list and a skid layout before the final isometrics exist.

Automated valve packages

Almost every valve on a data center water system is automated, because the plant runs from the building management system with a small operations crew: chemical dosing on and off with the metering pumps, blowdown control on conductivity, RO CIP sequencing, regeneration step valves on the demineralizer, tower isolation and bypass. We assemble automated valve packages in-house: the lined valve with a pneumatic or electric actuator sized to it, positioner or limit switches for feedback to the BMS or PLC, solenoid, and fail-safe action set the way the sequence needs it, spring-closed on a hypochlorite or acid feed, for example, so a power or air failure stops the chemical. Each package is mounted, stroked and leak-tested before it ships and arrives tagged to your valve schedule, so the controls contractor wires one tested unit instead of assembling parts on a ladder. Our services page describes the automation shop; send the valve schedule with the instrument and air specifications and we will quote the packages with the spools.

Where the campuses are

Hyperscale and colocation campuses are concentrated in Northern Virginia, the Dallas and San Antonio areas of Texas, metro Atlanta, the Phoenix area, central Ohio, Oregon and Iowa, with more in Nevada, Illinois and the Carolinas. The dry-climate sites in Arizona, Nevada and West Texas, and water-constrained sites elsewhere, are where on-site water treatment and reuse go furthest, and where the lined chemical systems are largest. Our state pages for Virginia, Texas, Georgia, Arizona, Ohio and Oregon describe the wider industrial base in each.

Standards

Our lined pipe and fittings comply with ASTM F1545, fittings conform dimensionally to ANSI B16.5 and are welded to ASME B31.3 by welders certified to ASME Section IX, and every lined spool and fitting is spark tested at a minimum of 10,000 volts before it ships. The chemistry on a data center campus is covered in more depth on our pages for chlorine and sodium hypochlorite, sulfuric acid, caustic soda and high-purity water. Send the chemical list, concentrations and line sizes and we will mark up which lines need lining and quote those. Call (251) 625-4949 or contact us online.

FAQ: Lined Pipe for Data Centers

Does a data center need lined pipe at all?

Only for its treatment chemistry: hypochlorite, acid, biocide and inhibitor feed at the cooling towers, the acid and caustic regeneration and CIP systems in the RO and demineralizer plants, and the chemical lines in an on-site water treatment or reuse plant. The chilled water, condenser water, glycol and liquid cooling loops do not need it.

Which liner for 12.5 percent sodium hypochlorite feed to a cooling tower?

PTFE, vented, with no dead legs, on a dedicated line, with lined diaphragm valves or ball valves with a vented ball (vent facing upstream). Never run it in a header shared with sulfuric acid or bisulfite: hypochlorite releases chlorine gas when it meets acid, and it reacts with bisulfite and gives off heat. PVDF is an option only for dilute or on-site hypochlorite at pH 12 or below. Send the layout and we will mark the liner for each line.

Can you supply the regeneration piping for a demineralizer feeding a liquid cooling loop?

Yes. Hydrochloric or sulfuric acid and sodium hydroxide regeneration lines, the bulk chemical transfer and the spent regenerant neutralization are standard lined pipe services. The deionized water polishing loop and the coolant distribution units themselves stay in stainless and engineered plastics.

Can you work to a campus energization schedule?

A feed package can be quoted from a chemical list and skid layout before final isometrics exist. Tell us the start-up date for the first cooling plant and we will quote the package, valves and automation with a fabrication time against it.

Can you supply the automated valves for the chemical feed and water plant?

Yes. We assemble automated valve packages in-house: lined ball, plug, butterfly or diaphragm valves with pneumatic or electric actuators, positioners or limit switches for the BMS or PLC, solenoids and fail-safe action, mounted, stroked and tested before shipment and tagged to your valve schedule. Send the schedule and the instrument and air specifications with the chemical list.