Senior Process Engineer – Water & Wastewater Treatment

Urban Ridge Supplies; Riyadh; On-site; SAR 337,000 - 562,000; Full time

Job summary

PACT Engineering FZC is seeking a Senior Process Engineer with extensive experience in water treatment, desalination, and wastewater projects. You will independently develop process designs, perform calculations, prepare technical docs, and coordinate with multidisciplinary teams on EPC and packaged treatment plant projects.

The ideal candidate has 8–10 years of direct water/wastewater experience, strong RO design knowledge, and proficiency in AutoCAD and Excel.

Qualifications

• 8–10 years direct experience in water and wastewater treatment engineering.
• Strong knowledge of RO design, membrane systems, filtration, and hydraulic calculations.
• Familiarity with AWWA, ASTM, ASME and international water treatment standards.
• Proficiency in AutoCAD, MS Excel, and engineering calculation tools.

Responsibilities

• Develop and review PFDs, P&IDs, process descriptions and design basis documents.
• Perform process calculations, hydraulic calculations, mass balances, and equipment sizing.
• Coordinate with mechanical, electrical, instrumentation, and automation teams; review vendor offers and drawings.
• Support HAZOP, design reviews, FAT, pre-commissioning, commissioning, and performance testing.

Skills

Process design

Engineering calculations

English communication

Education

Bachelor's degree in Chemical Engineering

Environmental Engineering

Tools

AutoCAD

MS Excel

WAVE

ROSA

Job description

PACT Engineering FZC is seeking an experienced Senior Process Engineer with strong technical expertise in the design and engineering of industrial and municipal water treatment, desalination, and wastewater treatment plants. The successful candidate must be capable of independently developing process designs, performing engineering calculations, preparing technical documentation, and coordinating with multidisciplinary engineering teams for EPC and packaged treatment plant projects.

Key Responsibilities

Process Design & Engineering

• Develop and review Process Flow Diagrams (PFDs), Piping & Instrumentation Diagrams (P&IDs), process descriptions, and design basis documents.
• Perform process calculations, hydraulic calculations, mass balances, and equipment sizing.
• Design and select water and wastewater treatment processes, including:
  • Reverse Osmosis (RO), Ultrafiltration (UF), and Multimedia Filtration (MMF).
  • Activated Carbon Filtration, Greensand Filtration, and chemical pretreatment.
  • Clarification, coagulation, flocculation, and sludge treatment.
  • Sewage Treatment Plants (STP), MBR, MBBR, SBR, and biological treatment systems.
  • Chemical dosing, neutralization, disinfection, and CIP systems.
• Prepare equipment datasheets and technical specifications for pumps, vessels, filters, blowers, mixers, and chemical dosing systems.
• Prepare hydraulic profiles, pump head calculations, and control philosophies.
• Develop process control narratives, cause‑and‑effect matrices, and operating sequences.

Project Engineering & Coordination

• Review vendor technical offers, drawings, calculations, and equipment selections.
• Prepare technical bid evaluations (TBE) and vendor document review comments.
• Coordinate with mechanical, electrical, instrumentation, automation, and project engineering teams.
• Review 3D models and equipment layouts for process compliance and accessibility.
• Respond to client technical comments, RFIs, and engineering clarification requests.
• Support HAZOP, design reviews, FAT, pre-commissioning, commissioning, and performance testing.

Technical Requirements

• Bachelor's degree in Chemical Engineering, Environmental Engineering, or a closely related discipline.
• Minimum 8–10 years of direct experience in water and wastewater treatment engineering.
• Strong knowledge of RO design, membrane systems, filtration, chemical dosing, and hydraulic calculations.
• Familiarity with relevant AWWA, ASTM, ASME, and international water treatment standards.
• Proficiency in AutoCAD, MS Excel, and engineering calculation tools.
• Experience with membrane design software such as WAVE, ROSA, or equivalent is an advantage.
• Strong technical reporting, engineering documentation, and English communication skills.

Candidate Profile

We are looking for a technically strong engineer who can independently take a water treatment project from design basis through detailed engineering and support commissioning, rather than someone experienced only in plant operation or maintenance. Preference will be given to candidates with EPC contractor, water treatment OEM, or engineering consultancy experience.