gold recovery from refractory and double-refractory ores and concentrates


for polymetallic complex concentrates and novel applications


design solutions for any location or environment

60 L to
1,200,000 L

autoclave design capacities


Some ores or concentrates can be processed economically and more environmentally friendly at high-temperature and high-pressure for high metal or mineral recovery. Increasingly, materials not historically treated using hydrometallurgical methods are being processed using pressure hydrometallurgical methods.

High pressure hydrometallurgical unit operations utilizing autoclave technology and associated equipment have been exploited for the treatment of sulphidic or oxide ores and concentrates for the recovery of many important elements (Au, Cu, Co, Mo, Ni, U, Zn, and platinum group metals). The increase in complexity of newer polymetallic ore bodies, often containing deleterious elements (As, Hg) requires more sophisticated processing such as:

  • Pressure Oxidation (POX)
  • Pressure Oxidative Leach (POL)
  • High Pressure Acid Leach (HPAL)
  • HCl Pressure Leach

Hatch has been at the forefront of implementation of pressure hydrometallurgical processes for over 25 years and is the technology provider of choice for many resource companies. To select the correct process, capital costs, operating costs, metal recovery, and environmental impacts must be considered. Autoclave circuits can be the most capital-intensive areas in a processing plant, and therefore it is vital to maximize their availability and utilization to optimize operational economics.


Each autoclave project is site and ore-specific. Resource companies need an engineering partner with the right experience and expertise to provide the best solutions.

Hatch’s High Pressure Metallurgy (HPM) practice consists of a dedicated, full-time staff of more than 60 skilled professionals focused on the execution of autoclave projects. With over 25 years of design experience and a team including project managers, metallurgists, chemical, mechanical, refractory and piping engineers, mechanical and piping designers, layout specialists, welding technologists and quality control inspectors, Hatch HPM delivers unmatched project solutions.

Every pressure hydrometallurgical circuit is a custom design. With the right innovative and proprietary equipment designs, your pressure oxidation or pressure leaching needs will be effectively met, from pilot-scale unit operations and demonstration plants to commercial facilities. 

Our services are tailored to the requirements of your project. We provide the entire range of project activities, from metallurgical test work through to commercial plant construction and commissioning, following an established approach aligned with project requirements.

We provide the following project life-cycle services:

  • Scoping level, pre-feasibility, and feasibility engineering studies
  • Basic and detailed engineering execution
  • Construction management, commissioning, and start-up / ramp-up support
  • Brownfield debottlenecking and optimization studies and execution
  • Operations support
  • Specialized services include:

  • Bench-scale and continuous metallurgical test work planning and management
  • Metallurgical design development and process modeling (METSIM®, SysCAD®)
  • Proprietary and custom equipment design, fabrication, and supply
  • Specialized off-gas handling, heat recovery, and mercury abatement (MACT)
  • Advanced computational analysis and modeling (CFD, FEA)
  • Process hazard and operability studies (HAZOP)
  • Layer of protection analysis (LOPA)
  • Safety instrumented systems design (SIS)
  • Materials testing, evaluation, selection, and condition monitoring
  • Equipment fitness for service evaluations (FFS)
  • Refractory and ceramic materials evaluation, failure analysis, and QA/QC
  • Procurement, expediting, and supply chain management
  • Quality management, material control, and inspection services
  • Advanced online operational process analytics (digital twin)


CFD: Computational Fluid Dynamics  |  FEA: Finite Element Analysis  |  MACT: Maximum Achievable Control Technology


yale zhang & thessy moodley

Digital Twin: more than a buzzword

Thessy Moodley and Yale Zhang
Hatch experts Yale Zhang and Thessy Moodley discuss Digital Twin technology, focusing on value delivery and improvement opportunities without getting caught up in the hype.
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