10t/h triple-effect evaporator for sodium chloride in the rubber additives industry

The 10t/h triple-effect sodium chloride evaporator is a continuous evaporation system specifically developed by Conqinphi for the rubber additives industry. It is suitable for high-NaCl mother liquor generated during the production of accelerators M, DM, and NS. The system has an evaporation capacity of 10t/h (240t/d) and employs a "triple-effect cross-flow + forced circulation + DTB crystallization" process. Steam consumption is ≤0.25t/t water, NaCl crystal purity is ≥99%, and whiteness is ≥85, making it directly usable as a feedstock for ion-exchange membrane caustic soda.

I.Triple-Effect Evaporator Technical Background

Typical rubber additive mother liquor characteristics: NaCl 180-220g/L, organic matter (M residue) 8000mg/L, COD 30000-40000mg/L, color 8000 times, temperature 90℃. Traditional single-effect evaporators consume up to 0.45t/t water, are prone to coking and foaming, and have high operating costs. This equipment, based on a triple-effect heat transfer stage and forced circulation flow, incorporates organic matter enrichment and incineration and NaCl refining modules, effectively addressing the two major pain points of energy consumption and resource utilization.

II.Triple-Effect Evaporator Process and System Composition

1.Triple-Effect Cross-Flow Forced Circulation: Live steam enters only the first-effect heating chamber. The temperature difference between each effect is ≥8℃, the vacuum gradient is -70→-82→-90kPa, and the evaporation temperature is 80→68→55℃, effectively inhibiting high-temperature polymerization of organic matter.

2.DTB Crystallization and Salt Separation: The third-effect output first enters the DTB crystallizer (low-temperature side) to precipitate anhydrous NaCl. After centrifugation, the dry basis purity is ≥99%, and the whiteness is ≥85. The organic-rich mother liquor is returned to the second effect for concentration to 60% (solids), pumped into the enrichment tank, and periodically sent to the plant's RTO for incineration. The system has no external discharge of impurities.

3.Anti-coking and Defoaming: The heating element uses 2205 duplex stainless steel + TA10 composite pipe, designed with a forced flow velocity of 3.5m/s; the evaporation chamber is equipped with a double-layer inclined plate + wire mesh demister, with online defoamer injection, resulting in a foam layer <150mm, extending the cleaning cycle from 2 days to 10 days.

4.Deep Condensate Treatment: The triple-effect condensate undergoes activated carbon decolorization + ozone catalytic oxidation, achieving COD ≤120mg/L and color ≤20 times, which is then reused as makeup water for circulating cooling water, saving 80,000 tons of fresh water annually.

III. Parameters of the Triple-Effect Evaporator

1.Total Evaporation: 10t/h (240t/d)

2.Steam Consumption per Unit: 0.25t/t water (triple-effect); MVR interface reserved, ≤0.08t/t water after upgrade

3.Heat Transfer Area: 160m² for the first effect, 140m² for the second effect, and 120m² for the third effect, totaling 420m², with a 20% design margin

4.Crystallizer: One Φ2200 DTB unit, material 2507 + rubber lining, design pressure -0.1MPa

5.Centrifugal Drying: Two-stage piston pusher centrifugal drying + paddle drying line, product moisture content ≤0.3%, packaging capacity 2t/h

IV. Performance and Advantages

1.Low Energy Consumption: Triple-effect + DTB + heat pump reuse, steam cost is reduced by 44% compared to single-effect; after full MVR upgrade, steam consumption is almost "zero".

2.Resource Utilization: NaCl meets refined industrial dry-basis standards, increasing the external sales price from 200 RMB/t to 550 RMB/t; organic matter is enriched and incinerated, recovering 3.0 GJ/t of calorific value.

3.Stable Operation: Forced circulation + online cleaning, annual operating time ≥8000h, equipment availability >98%.

4.Space Saving: Modular steel structure frame, single-layer layout, occupying only 280m², 25% less space than traditional triple-effect evaporators.

5.Intelligent Control: DCS+SIS dual redundancy, key parameters with two-out-of-three voting; remote monitoring control software, fault SMS push notifications.

V.Benefits of this 10t/h rubber additive triple-effect evaporator

Based on steam price of 180 RMB/t and electricity price of 0.65 RMB/kWh, the triple-effect evaporator saves approximately 6 million RMB in steam costs annually; NaCl resource utilization generates an additional 4 million RMB in annual revenue. Carbon reduction of 0.28tCO₂ per ton of water, total annual emission reduction of 25,000 tons

VI. Kangjinghui Triple-Effect Evaporator Service and Upgrade Path

1. One-stop turnkey solution for design, manufacturing, installation, commissioning, and operation and maintenance.

2. 48-hour response time, real-time online remote cloud diagnostic center.

3. MVR compressor can be connected to the live steam inlet bypass in the future, and the connection can be completed within 72 hours of shutdown, reducing steam consumption to 0.08t/t water in one step.