Buffer Purpose

Ultrapure water systems operate continuously but demand varies. Reverse osmosis or deionization produces steady flow while polishing, distribution, and use consume variably. Buffer tank absorbs variations preventing production equipment cycling.

Tank Design

Vertical atmospheric or slight pressure vessel with treated water inlet from upstream process, vent system maintaining atmospheric or inert blanket, outlet to downstream polishing or distribution, level control, overflow protection.

Material Selection

Stainless steel 316L electropolished for ultrapure water applications. Surface finish Ra 15-25 microinch prevents contamination. Sanitary connections and fittings. Internal surfaces meet semiconductor or pharmaceutical purity requirements.

Capacity Sizing

Volume provides 15-60 minutes storage at average demand. Adequate capacity reduces upstream equipment starts. Balance between surge capacity and water age preventing quality degradation from extended storage.

Operating Pressure

Atmospheric operation simplest for moderate systems. Slight pressure 5-15 psig for distribution assistance. Pressure rating per ASME codes. Vent system maintains design pressure.

Water Quality Protection

Nitrogen or clean dry air blanket prevents atmospheric contamination. Sealed system excludes particles and microorganisms. Proper venting prevents vacuum during withdrawal. Materials prevent ionic or organic contamination pickup.

Level Control

High level indicates adequate production. Low level signals insufficient upstream capacity or excessive demand. Controls coordinate with production equipment and distribution pumps.

Applications

Semiconductor ultrapure water systems, pharmaceutical purified water, laboratory reagent water, power plant high-purity makeup, and any ultrapure application requiring production-demand buffering.

Temperature Control

Jacket or immersion cooling maintains target temperature for sensitive applications. Temperature stability important for semiconductor processes. Insulation reduces external heat gain.

Mixing Consideration

Generally unmixed preventing stratification and maintaining first-in-first-out flow. Some applications require gentle recirculation preventing stagnant zones. Design based on water age and quality requirements.

Sanitization Capability

Hot water or chemical sanitization capability for pharmaceutical systems. Temperature ratings and materials accommodate periodic sanitization cycles. Drainage for complete water removal.

Instrumentation

Conductivity monitoring verifies water quality. Temperature measurement tracks conditions. Level transmitters coordinate system operation. TOC analyzers for ultrapure applications.

Performance Benefits

Stabilizes production equipment operation reducing starts. Provides surge capacity accommodating demand variations. Protects water quality through proper design. Enables optimized upstream equipment sizing.

Construction Standards

Stainless steel vessels per ASME BPE for bioprocessing equipment. Surface finish specifications for ultrapure water. Sanitary design per 3-A standards where applicable. Complete documentation with material certifications.

ERGIL buffer tanks provide intermediate storage stabilizing ultrapure water system operation between production and consumption in semiconductor and pharmaceutical applications.