Technical Datasheet

Service / Application: Separation of water (low-boiling) from ethylene glycol (high-boiling) in polyester/ethyl acetate production — recover EG to reactor.
Design pressure (MAWP): 0.10 MPa (gauge)
Specified test pressure: 0.41 MPa (hydrostatic) — use as provided; verify with code.
Working temperature: 130 °C
Material of construction (shell / internals): Stainless steel (recommendation below)
Net weight (empty): 13,564 kg
Process type: Continuous esterification separation (rectification / vapor-liquid separation)
Primary function: Remove/gas-liquid separation; top product = water + light components (to condenser), bottom = ethylene glycol to bottoms pump / re-circulation.

Key design assumptions (made for this datasheet)

1. Tower operates at near-atmospheric pressures (you specified 0.1 MPa gauge).

2. Tower separates water/EG by volatility — internal configuration will be packed bed or trays depending on required separation efficiency and ΔP limits.

3. No corrosive halides or HCl present beyond typical process trace amounts. If acids/sulfuric catalyst contact tower surfaces, validate materials.

4. Test pressure of 0.41 MPa will be used for hydrostatic testing as you supplied — ensure this meets the applicable pressure vessel code for your jurisdiction.

Materials recommendation

Shell & heads: Stainless steel 316L (recommended) — better resistance to organics, water and potential acidic traces at 130 °C. If chloride or halide exposure expected, consider higher alloy (e.g., 317L) or apply lined / clad options.

Internals: 316L or 316Ti where higher creep/thermal stability needed. For packing, use 316L stainless structured packing (e.g., Mellapack, KATAPAK) or ceramic packing if fouling/catalyst concerns.

Gaskets & seals: PTFE / graphite as appropriate for 130 °C and process fluids.

Bolting: Duplex or stainless bolting with anti-seize; match corrosion resistance.

Internals & separation options

Structured packing (recommended if low ΔP, high efficiency, and low fouling): lower pressure drop, good for vacuum/low-pressure service.

Sieve / valve trays (recommended if heavy fouling or solids/catalyst present): more tolerant of fouling, easier maintenance.

Redistributors and liquid collectors sized per flow rates.

Downcomers and weirs designed for intended hydraulic load.

(Choose packing vs trays based on required stages, reflux ratio, allowable pressure drop and fouling tendency.)

Mechanical design highlights

Nozzle schedule: supply nozzles for feed, top vapor outlet, reflux return, bottom draw, vents, drains, instrumentation (level, temperature), manway(s). Specify sizes and orientations in P&ID.

Manways: full-size manway for internals removal (size per vendor practice).

Supports: skirt or saddle support consistent with vessel weight (13,564 kg empty + filled weight). Provide anchor points for piping loads.

Insulation: required to reduce heat loss at 130 °C; cladding as per plant standard.

External coating: stainless surface finish; insulation & weather jacketing.

Instrumentation & controls (minimal recommended list)

Top vapor temperature (1)

Bottom liquid temperature (1)

Multiple tray/packing column temperatures (2–4) for profile monitoring

Level transmitter(s) on bottoms (1) and liquid distributor / reflux drum (1)

Pressure transmitter (top) and pressure safety devices

Pressure safety valve / rupture disc sized to relieve to safe location — setpoint per code and MAWP.

Sample points (top and bottom) and sampling ports.

Flow meters for feed, reflux (if controlled) and product draw.

Reflux drum with condenser and duties sized per vapor load.

Emergency shutdown (ESD) interlocks with reactor & upstream equipment.

Safety devices & testing

Relief device(s): PSV(s) sized per API/ASME and plant safety philosophy. Provide discharge piping or flare/knockout.

Rupture disc as per manufacturer if required by process safety analysis.

Hydrostatic test: perform at 0.41 MPa (as you provided). Record test date, temperature, and results. (Important: confirm test multiplier vs code — many codes specify 1.3× MAWP for hydro tests; your provided value is 4.1× MAWP and must be verified.)

NDT & inspection: radiography/UT of welds per code, MPI/DP for surface inspections where required.

Painting/labeling: nameplate with MAWP, test pressure, serial, material, manufacturer, year.

Piping & aux equipment (process items to include)

Top condenser (shell & tube or air) for vapor from top. Condensate returns to reflux drum.

Reflux drum (vessel) with level control and reflux pump.

Bottom pump (for heavy EG): specify pump material compatible with EG at 130 °C and NPSH.

Heat tracing on samples and small bore lines if needed.

Vents to flare or safe recovery.

Pumps & coolers sized to maintain required reflux and recycle rates.

Commissioning & start-up checklist

1. Mechanical completion record with as-built drawings.

2. NDT & pressure test records — hydrostatic at 0.41 MPa (documented).

3. Instrument calibration and loop checks for level, pressure, temperature, flow.

4. PSV and relief system certification and blowdown routing.

5. Insulation & cladding inspection.

6. Control interlocks tested with upstream reactor and condenser.

7. First-fill leak checks at operating temperature (steam/thermal expansion verification).

8. Establish and document normal operating range and alarm setpoints.

Maintenance & inspection recommendations

Visual external inspection every 6 months.

Internal inspection (thorough) at intervals required by code or every scheduled turnaround (typical 1–3 years depending on duty & corrosion).

Inspect internals (packing/trays) for fouling; clean/replace as required.

Check bolting torque and flange integrity after first heat cycle.

Recalibrate instrumentation annually.

Process/engineering notes & recommendations (action items)

Confirm duty & flow rates, vapor load, required separation (specs for EG purity and top-end water content). Those determine tray count or packing height, column diameter, and internals selection.

Confirm corrosive species (e.g., sulfuric acid traces, HCl) — if present, consider corrosion allowance, cladding or higher alloy.

Confirm applicable code/standard for vessel design & testing (ASME VIII Div. 1, PED, GB, etc.) and local requirements for hydrostatic test pressure. I used your supplied test pressure (0.41 MPa) but you MUST validate against the chosen code.

Provide process P&ID and material balance so vendor can size internals, condenser duty and pumps.

Deliverables you can request from a vendor

• Complete mechanical datasheet (MD) with nozzle schedule & weight.

• Thermal & hydraulic design report: column diameter, packing/tray design, stage count, pressure drop, condenser duty.

• Stress analysis & nozzle reinforcement calculations per code.

• Fabrication drawings, welding procedure spec (WPS), and NDE plan.

• FAT (factory acceptance test) procedure and commissioning support.