Chemical Process Density & Concentration Meter

PS7020 Series Ultrasonic Sound Velocity–Based Concentration/Mass Density Meter: Applications in the Food, Brewing, and Sugar-Refining Industries

In the wort mashing, filtration, and fermentation stages of beer brewing, customers face challenges such as delayed wort concentration measurements, bubble interference, and poor performance with dark-colored liquids, resulting in significant batch-to-batch variability and frequent manual sampling. The PS7020 series ultrasonic sound-velocity–based concentration/density meter measures wort °P online with an accuracy of ±0.0005 g/cm³, unaffected by color, bubbles, or CO₂. Equipped with a hygienic clamp‑type quick‑connect and compatible with CIP/SIP, it delivers sub‑second real‑time feedback and seamless integration with MES systems.

Online simultaneous analysis of two components: available chlorine and free alkali

Manual titration for available chlorine and free alkali delays the endpoint. The PS7100 spectroscopic concentration meter enables continuous online analysis for precise control.

Online Monitoring Solution for Methanol–Water Binary System

At the outlet pipeline of the circulation pump in the methanol distillation unit, the customer faced high risks of personnel exposure during manual sampling, a 2–3 hour delay in laboratory analysis, and an inability to adjust the water content in real time. The PS7100 explosion-proof spectral concentration meter was installed in a bypass flow cell, enabling simultaneous online monitoring of methanol and water content via near-infrared characteristic wavelengths, delivering sub-second response, non-contact measurement, and real-time DCS feedback.

HF + H₂SO₄ + H₃PO₄ + DI Water Simultaneous Monitoring of Multi-Component Tank Solution Concentrations

Semiconductor 12-inch wafer foundries face challenges in BHF and SPM etching tanks: the concentrations of the four components—HF, H₂SO₄, H₃PO₄, and DI water—are prone to drift, making real-time monitoring difficult; manual sampling is both hazardous and time‑lagged; and reliance on empirical judgment for tank‑change timing leads to chemical waste or yield degradation. The PS7100 spectral‑based concentration meter, equipped with a PFA‑lined flow cell and sapphire optical windows, delivers online, synchronous concentration measurements for all four components, enabling sub‑second feedback and precise management of bath life.

Octane number RON + MTBE + ethanol + aromatic hydrocarbons multi-component real-time blending optimization

At the refinery’s blending station, long-term reliance on offline octane analyzers has resulted in a 2–4 hour analysis lag, making edge‑of‑spec blending challenging, leading to excessive octane reserve usage, and frequent batches failing to meet specifications. The PS7100 explosion‑proof spectral‑based concentration/density meter is installed in a bypass flow cell downstream of the static mixer, providing second‑level, synchronized measurements of RON, MTBE, ethanol, aromatic content, and olefin content, with real‑time feedback to the BPCS for closed‑loop optimization.

Simultaneous online monitoring of three components: FAME, residual methanol, and free glycerol

In the biodiesel transesterification process, the customer relies on offline gas chromatography to determine the reaction endpoint, which leads to a 1–2 hour data lag, an overuse of methanol by 10%–15%, and fluctuations in the purity of by-products. The PS7100 spectral‑based concentration/density meter has been installed on the discharge line of the reactor and the FAME outlet pipeline of the separator. By acquiring full UV‑Vis‑NIR spectra and employing MLR modeling, it provides real‑time, synchronized measurements of FAME, residual methanol, and free glycerol concentrations. Once the reaction completion exceeds 96.5%, the process is automatically terminated, reducing methanol consumption by 11.3% and stabilizing the FAME content at 97.2%.

Real-time density tracking of polymerization reactions · Automatic determination of reaction end points

Customers face challenges in large-scale polymerization reactors, including delayed determination of the reaction endpoint, high safety risks associated with manual sampling, and poor batch-to-batch consistency. The PS7300 differential pressure density meter features a B‑bend flange‑mounted, single‑hole installation on the reactor top, bypassing the agitator and heating coils. It tracks real‑time changes in the reaction slurry’s density with a resolution of 0.001 g/cm³, supports DCS‑triggered automatic termination and runaway‑prevention alerts, and enables precise quantitative control of the reaction endpoint.

Zero Liquid Discharge (ZLD) for Industrial Wastewater · Precise Concentration Control in Chemical Concentration/Crystallization Processes

In chemical concentration and zero‑liquid‑discharge (ZLD) processes, customers face challenges such as the highly corrosive nature of high‑concentration brines in MVR evaporators, as well as the risk of crystallization leading to jamming of conventional density meters and shutdowns due to scale formation. The PS7300 dual‑flange differential pressure concentration meter features a side‑mount configuration with Hastelloy C‑276 diaphragms and a PFA fluoropolymer coating, offering exceptional corrosion resistance and resistance to crystallization‑induced wear. It enables long‑term, stable online monitoring of density converted to concentration, supporting DCS closed‑loop precision control, preventing scale‑related downtime, and enhancing the purity and recovery rate of by‑product salts.

Oil/Water/Gas Interface Online Monitoring · Intelligent Water Cut Estimation

Blended oil recipe control · Sanitary clamp + PFA coating · MES batch traceability

Online Concentration Monitoring of 40% / 50% Urea Solution Storage Tanks

In the urea solution storage tank area of a large fertilizer plant, challenges include lengthy manual sampling and laboratory analysis prior to loading, significant trade‑based discrepancies due to concentration drift when converting to 100% basis, elevated risks of low‑temperature crystallization, and difficulties in verifying automotive urea AdBlue compliance. The Pisonics PS7300 dual‑flange differential pressure density meter is installed side‑mounted on 40% and 50% urea solution storage tanks, providing real‑time density measurements that are converted into weight‑percent concentration. This data supports the DCS/MES systems in enabling five‑minute automated pre‑loading verification, automatic 100%‑basis trade reconciliation, crystallization‑warning‑triggered heat‑trace interlocks, and end‑to‑end compliance monitoring of the AdBlue feedstock.

LPG / Liquefied Petroleum Gas Trade Handover

In LPG trade handover, the conventional table‑lookup estimation method and manual sampling result in density measurement errors exceeding 0.5%, leading to commodity‑value discrepancies of hundreds of thousands of yuan for ten‑thousand‑ton‑level loading and unloading operations. The PS7400 explosion‑proof online tuning fork concentration meter is directly installed on the main pipeline for loading onto tank trucks or ships, delivering real‑time process‑condition density within seconds. When paired with a volumetric flowmeter and a flow computer, it enables real‑time mass settlement in compliance with the OIML R117 standard.

Online Concentration Monitoring of 32% / 48% NaOH Storage Tanks

In the concentration monitoring of 32% and 48% NaOH storage tanks, the customer faced challenges such as delays in manual sampling, short instrument lifetimes due to corrosion by high-temperature strong alkali, control lag in the evaporation section, and significant discrepancies in trade settlement. The PS7400 online tuning fork concentration meter, with wetted parts made of 316L and Hastelloy, delivers a concentration accuracy of ±0.1 wt%, operates reliably at temperatures up to 65°C, and reduces on‑truck verification time to within 5 minutes, thereby enabling DCS‑based closed‑loop energy savings and precise settlement of cargo payments on a 100‑ton basis.

Ammonia Water 20% / Urea Solution 40% Reductant Concentration Online Monitoring

In the SCR denitrification system of a thermal power plant, the concentrations of 20% ammonia solution and 40% urea solution drift due to evaporation or low-temperature crystallization, and the lag in manual sampling leads to fluctuations in NOx emissions and excessive ammonia slip. The PS7400 online tuning fork density/concentration meter is installed on the storage tank’s outlet pipeline to measure concentration in real time and transmit the data to the DCS for closed-loop control, enabling ±1% precision control of the reductant injection rate and ensuring stable compliance with ultra-low emission standards.

Marine fuel / HFO·VLSFO·MGO refueling measurement

At the ship refueling terminal, during the heated transfer of multiple fuel grades—including HFO, VLSFO, and MGO—real-time density measurement is required under high-temperature conditions of 80–95°C to convert flow rates into tonnage. However, conventional sampling analysis is time‑lagged, and contact-type instruments are prone to thermal drift and seal failure. The PS7400 high‑temperature tuning fork concentration meter is installed directly on the main pipeline downstream of the heater, operating reliably across the full temperature range of −25 to 150°C. Coupled with PT1000 temperature compensation, it delivers real‑time standard density at 15°C in accordance with ISO 91, enabling automatic BDN document generation and MARPOL Annex VI‑compliant settlement.

Inline ratio monitoring for cutting fluid and coolant

Inline refractometric measurement of cutting fluid, chilled fluid and emulsion ratio: continuous tracking in place of spot checks with a handheld refractometer, with CL1 / CL2 cleaning units and a small-bore adapter.

Chlorine tail-gas caustic scrubber — online residual-alkali monitoring

Online residual-alkali and available-chlorine monitoring on a chlorine tail-gas caustic scrubbing loop. The circulating liquor carries three solutes, but stoichiometry pins them to one reaction path, so a single sound-velocity reading locates it — while a density instrument barely sees the loop change at all. The page sets out both measuring points with their metallurgy and calibration basis, and the three mechanisms that make the reading run high.

What an “ultrasonic dual-parameter concentration meter” means: three routes

“Ultrasonic dual-parameter concentration meter”, as written on enquiry sheets, is not a category with an agreed definition. At least three technical routes answer to it: single-parameter sound velocity reduced to one dimension by stoichiometry, sound velocity plus a second physical quantity such as conductivity, and spectroscopic multi-component analysis. This page selects between them by how many numbers you actually need — and says what we do and do not have.

Dichloromethane / water extraction — DN32 inline phase detection

Phase discrimination when a pharmaceutical or fine-chemical reactor drains. Dichloromethane is a third denser than water yet sits at almost the same acoustic impedance, so density and impedance instruments are blind near ambient — while the sound velocities differ by 390 m/s. The page sets out how the two velocity bands are calibrated, how the rag layer is caught by amplitude, the timing and hold-up budget on a DN32 line, and the three conditions that push the reading to not-decidable.

Chloride-process titanium dioxide — tail-gas scrubber liquor monitoring

Online residual-alkali and available-chlorine monitoring on the caustic scrubbing loop of chloride-process TiO₂ chlorination tail gas. The liquor is structurally the same as a chlor-alkali tail-gas tower, and the field ranges in granted patent CN111678951B (NaOH 0–15 %, ClO⁻ 0–100 g/L) agree with the switch-out point computed from the reaction equation. This page covers only what differs: HCl in the gas, possible solids, and more complex corrosion.

Hydrogen chloride absorption — acid strength and scrubber liquor monitoring

The two hydrogen-chloride routes measure different things. Water absorption is a binary HCl–water system and the number holds the product acid strength; caustic absorption is a one-dimensional NaOH → NaCl path and the number is neutralising capacity left. Neither measurement is hard; all the difficulty is in wetted materials. This page sets the boundaries of PTFE lining, tantalum, C-276 and titanium — and notes that titanium suits hypochlorite but not plain reducing hydrochloric acid, so the experience does not carry across.

Emergency chlorine absorption — online monitoring of the circulating caustic

GB 11984—2024 clause 6.1.3 d) requires the circulating liquor of a liquid chlorine emergency absorber to hold 15–20 % sodium hydroxide at not more than 45 °C leaving the tower, with online monitoring of concentration and temperature, periodic laboratory analysis, and replacement before caustic falls below 5 %. This page sets out the fact that decides the selection: a standby absorber holds plain caustic, a binary system that sound velocity handles directly; it only turns ternary after an actual release. Also covers raising the strength on existing units, why carbonation is invisible online, and the materials clauses in both standards.

Solvent / water washing — interface detection on toluene, ethyl acetate and hexane circuits

Interface detection on a multi-product line, where the same drain runs toluene this week and ethyl acetate next. Any discriminator tied to colour, conductivity or density has to be re-validated at every changeover. The page tabulates the velocity gap between water and a dozen common solvents (the closest pair still 155 m/s apart), what temperature and salt do to that gap, where the method stops working, and how recipe-based thresholds handle changeovers.

How to measure caustic strength in an emergency chlorine absorber

Titration, pH, conductivity, density, ultrasonic sound velocity and ORP, each judged against the 15–20 % window GB 11984—2024 requires. The focus is conductivity: authoritative data tables put the NaOH conductivity maximum in or against that very band, and one electrodeless caustic meter is sold in 0–10 % and 25–40 % ranges with 10–25 % simply absent. The page also states plainly that we do not claim sound velocity is proven monotonic across the range — monotonicity is established by calibration on the customer's own loop.

Nitrogen trichloride discharge treatment — caustic strength monitoring

GB 11984—2024 clause 5.1.1 requires sodium hydroxide in the nitrogen trichloride discharge treatment facility to be 5–20 %, with discharge frequency set by keeping NCl₃ below 0.5 % by mass. This is the second caustic measuring point in the same standard; the medium is clean and binary, so the measurement is simpler than on an emergency absorber. The page also says plainly that a tank blown down a few times a year with no circulation is adequately managed by laboratory analysis, and the money is better spent on the emergency absorber.

Hydrogen peroxide (anthraquinone process) — phase detection on the extraction section

Two-phase detection around the extraction column of an anthraquinone peroxide plant. The working solution and the 27-35 % peroxide aqueous phase sit over 150 m/s apart, so the call itself is easy; what matters is that carry-over is asymmetric — organics in the product is a quality problem, peroxide returning to hydrogenation is a safety one. The page covers the measuring points, the materials and passivation a peroxide plant demands, and three things this instrument explicitly does not do.