**4.4 Improve**

To look for improvements in a process, it is necessary first to understand the engineering/design process. Unfortunately, the current process lacks this documentation, making it hard to identify a flaw in the engineering design or if the operation is out of design operating conditions. However, the problems and variability caused by the lack and understanding of this documentation continuously show up, which is a wake-up call to adopt a process methodology like Six Sigma. That is why the Engineering/design process and documentation are some of the drivers of Six Sigma. (1) Key technology and process description, (2) General mass balance, (3) General energy balance, (4) Thermal Rating, (5) Process flowsheets, (6) Piping and (7) Instrument Diagrams, (8) Definition and sizing of significant equipment resulting in the process specifications, (9) Definition of control and safety devices, (10) Mechanical data sheets of the leading equipment, (11) HAZOP.

Poor industrial process capabilities often result in high COPO (rework, scrap, field failure).

Piping clogging: Gasification also produces tars, a combination of char and oils. When the gas temperature decreases, tars condensate and clog the exhaust pipe (**Figure 2**, section M). This problem can be caused by poor heating in the exhaust pipe, inappropriate feedstock flow for the facilities, or the wrong size of pipes and equipment. This results in high COPO (rework, scrap, field failure).

#### *4.4.1 Brain-writing*

*Temperature control:* (1) Replace the cooling temperature system with an internal serpentine can help to provide temperature homogeneity. In addition, this serpentine can be sectioned along the reactor body to provide better temperature profile control. **Figure 12** depicts the internal serpentine with a cooling water supply nozzle and a cooling water supply return.

