When investigating an industrial incident, one piece of information I always ask for is the relevant P&ID’s for the process. P&ID stands for Piping and Instrumentation Diagram and is defined as “A schematic diagram of the relationship between instruments, controllers, piping, and system equipment.” A set of P&ID’s for an entire facility allows you to trace the entire manufacturing process from raw material unloading to finished product loadout, including utilities like steam, water, fuel, and air. That’s great information to have, but isn’t especially useful Read More
The Safety Hierarchy states that hazards should be mitigated first by engineering controls, secondly by guarding, and lastly by warning/training. When the first two, engineering controls and guards, fail in a manufacturing setting, a chemical release could occur. A forensic chemical engineer can help determine the root cause of that failure. Read More
Now that you know what ammonia is (see Part One here), how it behaves, and how to safely store it and work with it, let’s look at some areas in industry where it is used.
Anhydrous ammonia has a use in pollution control. Industrial boilers and power plants burn coal or natural gas to make steam and/or electricity. When the fuel is burned using air as the oxygen source nitrogen gets exposed to the heat as well because air is 79% nitrogen. The nitrogen gets oxidized and forms several compounds referred to as NOx (NO, NO2, NO3). NOx compounds are harmful to Read More
Ammonia is a compound consisting of one nitrogen atom and three hydrogen atoms and is denoted by the formula NH3. Its boiling point is -28°F at atmospheric pressure, so unless it is under pressure, it is gaseous at room temperatures. Therefore, pure ammonia is typically stored under pressure in a liquid form. Household ammonia is only 5-10% NH3, the remaining 90-95% is water. Ammonia is extremely soluble in water. It is often depicted like this: Read More
Wouldn’t it be great to have a built-in camera to let you see exactly what went wrong before an incident? In many manufacturing instances there is, chemical plants especially. The computer system that operates the plant is called a Distributed Control System (DCS) and it has the capacity to monitor thousands of process variables (flow rates, temperatures, pressures, levels, valve positions, pumps on/off) simultaneously. Read More
The thirty-thousand-foot view of manufacturing is raw material in, alter in an appropriate fashion, finished product out, by-product out. Since the finished product keeps a business in business, it gets the most attention. What about by-products or waste streams? Read More
Fire. Something about fire touches our brainstems…both good and bad! Uncontrolled fire is terrifying and deadly to be sure. But the controlled burning of wood at a campfire or in a fireplace in your home almost can’t be beat, to my mind! For that very reason, a fairly common amenity to houses nowadays is the gas log fireplace insert.
When not installed properly, these logs will generate soot. These soot particles can leave the fireplace and meander. All. Over. Your. House. Read More
Remember the good old days when our homes were built with only lumber, dry-wall, and roofing? Me neither. However, we talk about ‘modern’ construction materials like this is a new phenomenon. The truth is ‘modern’ construction materials started sneaking into homes over fifty years ago. It’s not only construction materials that have changed: a century ago, we furnished our houses with wood, cloth, metal, and glass. Today, it’s plastics, foams, and coatings.
In February of 1992, the OSHA Process Safety Management (PSM) standard was issued. The official title is: ‘Process Safety Management of Highly Hazardous Chemicals.’ As its title implies, not every facility is covered by this rigorous standard. A process must contain highly hazardous, as defined by OSHA, chemicals above a certain weight threshold, again defined by OSHA. Notice that this is a process by process determination, so there could be certain processes at a manufacturing facility that are not covered by this standard situated beside other processes that are.
When thinking about the safe operation of boilers (and don’t we all?), several systems can readily be named; flame control, fuel/air ratio; steam pressure control, levels in the vessel, etc. What about the water? It seems so passive, as long as there is enough for level control, what’s the big deal? Well, it turns out, that as the steam produced by a boiler is used in the process, the condensate from that steam is returned to the boiler as feedwater. However, since 100% of the condensate is not returned, whatever solids had been in that water before it evaporated to form steam are left in the remaining water. Fresh feedwater is added to maintain levels, but even fresh water contains some dissolved solids. So over time, the water in the boiler system gets saturated with all sorts of dissolved minerals.