Nickel heat exchanger + nickel reactor selection_5 equipment +3 materials +5 traps

Published by Engineering Team, Shaanxi Qianyi Tuoda Technology Co., Ltd on 2026-07-24

Wang Gong, equipment supervisor of a chlor-alkali enterprise in Jiangsu Province, once encountered equipment corrosion problems, Titanium reactor was used to treat 50% boiling NaOH evaporation, Alkali brittle perforation occurred after two months of operation, Material loss.Titanium material in high temperature concentrated alkali environment with concentration higher than 50%, in particular unde molten alkali conditions with temperature exceeding 120 DEG C, Alkali embrittlement and uniform corrosion are easy to occur, After replacing N6 pure nickel reactor, Stable operation of equipment for many years, Corrosion was improved.This paper combines Baoji China titanium valley nonferrous metal manufacturing practice, System disassembly nickel equipment selection logic, help industry, chlor-alkali, lithium, Hydrometallurgical industry to do a good job in material selection.

Nickel equipment is an important anticorrosion equipment in chlor-alkali, lithium salt and hydrometallurgy fields.Nickel and titanium are complementary to each other, titanium is more suitable for oxychloride, seawater and nitric acid conditions;Nickel is more suitable for high temperature concentrated alkali and reducing acid conditions.The corrosion rate of pure nickel is lower than 0.05mm /year under boiling condition of 50% NaOH, Adaptable to multiple concentrations, Temperature conditions.This paper focuses on nickel equipment category, application industry, price reference, Selection parameters, Processing points, Procurement risk point development complete selection description.

Nickel equipment is mainly divided into shell and tube heat exchanger, reactor, evaporator, tank, electrolytic cell parts five categories.Shell-and-tube heat exchangers are mostly used in alkali preheating and cooling scenarios;Capacity ≤2m³ jacketed reactor suitable for caustic soda evaporation, lithium hydroxide synthesis;Evaporator, concentration kettle for 50‑70% boiling caustic soda concentration;Tank lining is mostly used for atmospheric large storage tanks;Electrolyzer parts service nickel electrolysis, nickel salt electrolysis conditions.In actual projects, N6 all-nickel reactors are mostly used for caustic soda and lithium salt synthesis conditions with a volume of ≤2m³;N6 shell-and-tube heat exchanger is selected for alkali solution heat exchange and cooling;Under medium and low pressure conditions with volume greater than 3m³, N6+ Q345R nickel-steel composite plate kettle is preferred.

From the point of view of material structure, it is divided into three schemes: all-nickel equipment, nickel-steel composite plate equipment, carbon steel shell plus nickel lining.All-nickel equipment High purity, Not easy to produce impurity pollution, Suitable for small volume and high pressure conditions, But nickel density 8.89g/cm³, About twice as much titanium., High material costsNickel-steel clad plate equipment is suitable for medium and low pressure projects with a volume greater than 3m³, 40 - 55% cost optimization possible, Be aware of the cladding once perforated, Easy to appear bulging, Composite plate cladding thickness recommended to control 3‑5mm, Not less than 2mm, Avoiding the risk of weld penetration, Composite interface shear strength according to NB/T47002 standard, Not less than 140MPaCarbon steel shell with nickel lining procurement cost is lower, mostly used for atmospheric large storage tanks.Simple selection reference: small volume high pressure, the purity of the material has requirements to choose all nickel;Nickel steel clad plate shall be selected for medium and low pressure of large volume;Lining structure is selected for atmospheric large storage tank.

Nickel equipment is widely used in six industries, Chlor-alkali industry handles 50‑70% boiling caustic soda medium, Select all nickel reactor with nickel evaporatorLithium salt industry for lithium hydroxide, lithium carbonate alkaline mother liquor, configuration of all nickel reactor, nickel evaporator;Electrodeposition of nickel, cobalt and manganese in hydrometallurgical industry, Dilute sulfuric acid environment without high valence oxidizing ions, Nickel electrolyzer and lined cellAlkaline hydrolysis saponification process of pharmaceutical intermediates uses all-nickel reaction kettle;The fatty acid distillation process is matched with an all-nickel still;High purity nickel equipment shall be selected for nuclear grade high soda ash working condition.

In terms of brand differentiation, N6 (Ni200) is preferred for alkali solution conditions with design temperature ≤315℃;Temperature above 315℃, Or after welding is completed, heat treatment cannot be performed., N4 (Ni201) should be selected, Carbon content ≤0.02%), Avoiding graphitization risks, N4 is suitable for temperatures up to 600℃.The shell side medium contacts with the material, and N6/N4 plates are selected;Shell side medium is steam, water purification, N6+ Q345R composite plate can be used, NB/T47002 compliant, Coating thickness 3‑5 mm.

The price is the industry reference interval, DN400 specification 10㎡N6 shell and tube heat exchanger reference quotation 2.2‑3.0 million yuan, 50㎡ specification reference 4.5‑ 60,000 yuan;PN1.6 pressure class 1m³N6 all-nickel jacketed reactor reference 45,000 yuan, the same specification N6+ Q345R composite plate reactor reference 28,000 yuan.Nickel equipment cost mainly comes from nickel body, 50‑65% of total cost, The second is the cost of clad rolling, weld flaw detection, Machining costs.Under the same volume conditions, the weight of nickel equipment is about twice that of titanium equipment, and the material cost is 3 - 4 times that of titanium equipment.

Five key parameters need to be paid attention to in type selection: the first is to confirm the design temperature, and 315℃ is the boundary point for brand selection;Second combination GB/T5235, ASTM B162 Corrosion Curve Verification Alkali Concentration-Temperature Matching RelationshipThe thermal conductivity of the third nickel is about 90W/m·K, and the heat transfer performance is better than that of titanium.It is recommended to control the medium flow rate of the fourth pipe side to 1‑1.5m/s to reduce alkali scale deposition;The fifth nickel thermal expansion coefficient is 13.3×10/℃, which is close to the carbon steel parameters, and the equipment matching is better.Welding requires controlled weld heat input, Interlayer temperature control ≤100℃, Post-weld heat treatment avoids 425‑650℃ sensitization range, Avoid graphitization embrittlement.

There are five practical operations in the processing link., Pure nickel absorbs hydrogen and oxygen easily in liquid state, TIG welding requires purity ≥99.995% argon double-sided protection, With ERNi‑1 welding wire, strictly control interlayer temperaturePure nickel work hardening significantly, cold deformation 20% hardness will obviously increase, cutting tool selection sharp, cutting speed 80‑140m/min;Cold bending coil springback is large, and the processing process requires intermediate softening annealing at 700‑900℃;Heat treatment of N6 material avoids the range of 425‑650℃ to prevent graphitization;Due to rebound and cost constraints, nickel plate heat exchangers are rarely used in practical projects, and shell and tube structures are preferred for most working conditions.

Five types of risks need to be avoided in the procurement phase, N6 material impersonates N4 for high temperature conditions, Intergranular cracking occurs after long-term operationPurchase contract nominal N6, actual delivery of recycled remelted nickel material, alkali resistance is insufficient;Ni-steel clad plate coating thickness reduction, buried weld penetration, bulging hidden dangers;The tolerance control of nickel tube outer diameter is loose, and GB/T2882 precision standard is not implemented, resulting in misalignment of tube plate assembly;Monel400 copper-nickel alloy was supplied as pure nickel N6, and corrosion failure occurred under high concentration alkali condition.Purchase acceptance, Check the carbon content index in the warranty, N4 Carbon ≤0.02%, N6 Carbon ≤0.10%, Total nickel and cobalt content ≥99.5%, Spectrum sampling can be used for iron, sulphur, copper impurity content, Check the steel stamp number and furnace lot number, Confirm the actual thickness of the composite plate cladding, Distinguish Monel alloy from pure nickel.

Shaanxi Qianyi Tuoda Technology takes root in Baoji China Titanium Valley, All nickel available, nickel-steel composite, Nickel lining multi-scheme nickel equipment customization, Products Shell and tube heat exchanger with nickel, nickel reactor, nickel evaporator, Nickel-lined tanks, cell component, GB/T150, NB/T47002 and other national standards to carry out design and manufacture.Combined with medium, temperature and pressure parameters, material grades and equipment selection suggestions can be provided.

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Frequently Asked Questions

How to choose titanium and nickel equipment? Titanium is more suitable for wet chlorine, hypochlorite, seawater, nitric acid and other oxidizing chlorine-containing media;Nickel is more suitable than 50% high temperature concentrated alkali, no high ion reducing acid.Comprehensive evaluation of temperature, pressure and budget under other working conditions.

How to distinguish between N4 and N6 grades? ≤315℃ alkali environment N6;Temperature>315℃ or after welding heat treatment can not be selected N4, N4 maximum use temperature up to 600℃.

Why is nickel equipment procurement cost higher than titanium equipment? The density of nickel is about 8.89 g/cm³, and the density of titanium is 4.51 g/cm³, which doubles the weight of the same volume;The unit price of nickel raw materials is higher than that of titanium materials, and the comprehensive material cost is about 3‑4 times that of titanium equipment.

Can nickel plate heat exchangers be customized? Not many actual project applications, Large springback of nickel stamping, Thin sheets are prone to failure, Shell and tube preferred, Plate requirements can be evaluated in titanium or stainless steel options.

What consumables are used for nickel equipment welding? TIG argon arc welding adopts ERNi‑1 pure nickel welding wire, Argon purity ≥99.995% Double sided protection, Interlayer temperature control ≤100℃ reduces the risk of hot cracking.

How to reduce the risk of nickel equipment procurement? Check the quality assurance document composition index, spectrum sampling impurities, check the steel seal furnace batch number;Composite plate confirms coating thickness;Distinguish Monel400 from pure nickel materials, and arrange a third party for re-inspection under critical conditions.

information source, Shaanxi Qianyi Tuoda 12 years experience in nonferrous metal equipment projects, Refer to July 2026 Electrolytic Nickel MarketReference GB/T5235‑2021, GB/T2882, GB/T2054, NB/T47002.turnover time, 2026‑07‑22 disclaimer, This article selection ideas, Prices are for industry reference only, Pressure vessel equipment, please combine with actual working conditions, Consult professional and technical personnel for evaluation, The actual business cooperation shall be subject to the written contract signed by both parties.