300t/d Rubber Additives Mixed Wastewater Triple-Effect Evaporator

Conqinphi designed a 300t/d triple-effect evaporator for this client, suitable for wastewater from mixed processes involving accelerators M, DM, CZ, and NS. The designed evaporation capacity is 12.5t/h, employing a "triple-effect cross-flow forced circulation + low-temperature DTB crystallization" process. Steam consumption is ≤0.26t/t water, and the purity of byproduct Na₂SO₄ or NaCl is ≥98.5%, helping the client achieve the dual goals of "zero discharge" and resource recovery.

I.Influent Characteristics Typical mixed wastewater characteristics: Na₂SO₄/NaCl 150-200g/L, COD 30000-50000mg/L, color 15000 times, temperature 90℃, pH 2-4, containing trace amounts of aniline, thiazole, and sulfonic acid organic matter; prone to foaming, coking, and highly corrosive.

II.Process Scheme

1.Pretreatment Module: Cooling and oil removal → Neutralization (NaOH + CO₂) → High-density softening (MgO + PAC, F⁻≤10mg/L, Ca≤30mg/L) → Tubular microfiltration (SDI≤3)

2.Triple-Effect Cross-Flow Evaporation: Vacuum gradient -70→-82→-90kPa, evaporation temperature 80→68→55℃, forced circulation flow rate 3.5m/s, forced scale prevention; cross-flow operation avoids organic matter enrichment and coking.

3.Low-Temperature DTB Crystallization: Seed crystals are inserted at a discharge density of 1.25t/m³, anhydrous Na₂SO₄ (or NaCl) precipitates at 45℃, centrifugation water content ≤3%, whiteness ≥85; organic-rich mother liquor is concentrated to 60% and sent to RTO, the system has no waste liquid.

III.Core Parameters

1.Evaporation Capacity: 12.5t/h (300t/d)

2.Steam Consumption per Unit: 0.26t/t water (triple-effect); MVR interface reserved ≤0.08t/t water

3.Heat Transfer Area: 120m² for the first effect, 105m² for the second effect, 90m² for the third effect, totaling 315m², with a 20% margin

4.DTB Crystallizer: Φ2200×4500mm, 2507 + rubber lining, crystal slurry density 30%

5.Centrifugal Drying: LW530×2200-N, processing capacity 4t/h, product moisture content ≤0.3%

IV. Performance Advantages

1.Low Energy Consumption: Quadruple-effect stage + heat pump reuse, steam cost reduced by 42% compared to single-effect.

2.Resource Utilization: Impurity salt purity ≥98.5%, doubled sales price; organic matter calorific value recovery. 3.Stable Operation: Online CIP + forced anti-scaling, 8000 hours of operation per year, availability >98%.

4.Space-Saving: Modular steel frame, 280m² per floor, 25% smaller than traditional triple-effect systems.

5.Intelligent Operation: DCS + SIS dual redundancy, remote monitoring via control software.

V.Economic and Environmental Benefits: Annual steam savings of 0.9 million tons, equivalent to 1000 tons of standard coal, reducing carbon emissions by 2600 tons; increased revenue from miscellaneous salts of 5 million RMB per year.

VI.Service Guarantee:

1.One-stop turnkey solution from process package to operation and maintenance.

2.48-hour response time, nationwide spare parts warehouse, cloud diagnostic center.

3.Upgrade to full MVR within 72 hours of downtime, steam consumption <0.08t/t water.