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Reverse Engineering ALOHA: Modelling Thermal Radiation and Safe Fire Distances in Oil Refineries

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In this post, I want to share reverse engineering using ALOHA (Areal Locations of Hazardous Atmosphere) to model thermal radiation and safe fire distances. The original publication can be downloaded here.

The purpose of the study is to assess safe distance of thermal radiation exposure resulting from a tank fire (pool fire) scenario using ALOHA simulation software.

ALOHA (Areal Locations of Hazardous Atmospheres) is an industry-standard atmospheric dispersion modelling tool developed by the EPA and NOAA to predict how chemical releases spread during industrial accidents. By factoring in chemical properties, storage conditions, and ambient weather, it calculates precise threat zones for toxic plumes, explosions, and pool fires. Read More

Process Parameters for Biogas Production from Industrial Liquid Waste 4

Process Parameters for Biogas Production from Industrial Liquid Waste

Rifka Aisyah Leave a comment

In this post I want to share with you process parameters for biogas production from industrial liquid waste. By understanding required these parameters, optimal environment conditions for biogas production can be maintained. The parameters include temperature, pH and buffering systems, gas solubility, nutrients, and toxicity.

Process Parameters for Biogas Production from Industrial Liquid Waste
Process Parameters for Biogas Production from Industrial Liquid Waste

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How to Estimate Potential of Energy Generated from Biogas from POME (Palm Oil Mill Effluent)

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In this post, I’ll explain how to estimate the energy potential of biogas generated from Palm Oil Mill Effluent (POME). To convert POME into energy, it undergoes anaerobic digestion to produce methane-rich biogas. If you’re new to these concepts, feel free to check out my previous post on biogas and biorefineries.

Biogas Production from POME
Biogas Production from POME

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Sizing Indirect Fired Water Bath Heater with Example and Free Spreadsheet

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In this post I want to share with you how to size indirect fired water bath heater.

Indirect Fired Water Bath Heaters (IFWBH) safely heat various mediums by transferring energy indirectly. In this system, the process coils are submerged in a heated bath solution—typically a water-glycol mixture—which absorbs heat from the firetube and transfers it to the process media.

How Indirect Fired Water Bath Heater Works

Fuel gas burns inside a firebox submerged in the lower section of the water bath, transferring heat through the firebox wall to maintain the bath at the desired temperature. The process fluid (such as well fluids, natural gas, or oil) flows through a coil immersed in the upper section of the bath, where it is heated indirectly through the tube walls. A temperature controller regulates the fuel gas supply to the firebox to keep the water bath at an optimum operating temperature of 190°F. Operating above this threshold is inefficient, as it leads to excessive water loss through evaporation.

Indirect Fired Water Bath Heater Components
Indirect Fired Water Bath Heater Components

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Greenhouse Gas Emissions Calculations in Oil and Gas Industry

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In this post I want to share with you how to estimate greenhouse gas emissions in oil and gas industry.

Greenhouse gas (GHG) emissions from oil and gas production activities must be accurately estimated to enhance accountability and formulate efficient mitigation strategies. Particularly, the oil and gas industry is the largest source of methane (CH4) emissions within the energy sector. As the primary component of natural gas, methane is a significantly more potent GHG than carbon dioxide (CO2), trapping up to 25 times more heat in the atmosphere over a standard timeline. Read More

Mercury Removal in Oil and Gas Processing Facilities

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Mercury (Hg) can be present in feed gas in wide range of concentrations. It is important to remove mercury from the feed gas to avoid mercury attack on the brazed aluminum heat exchangers. Aluminum material is highly reactive with mercury and can be corroded quickly resulting heat exchangers failure and potentially can pose environmental and safety hazards. In addition, mercury will also cause poisoning precious metal catalyst if it presents in petrochemical process. This post outlines the method on mercury removal in oil and gas processing facilities.

Mercury Removal in Oil and Gas Processing Facilities
Mercury Removal in Oil and Gas Processing Facilities

Mercury presents in most natural gas field in concentration ranging from less than 10 ppb to more than 1 ppm as elemental (metallic), organic, and inorganic compound. Due to its strong affinity for higher molecular weight fractions, mercury predominantly concentrates within the liquid phase rather than the gas stream. Read More

Understanding Biogas Biorefineries: Definition, Process Flow, and Biogas Properties

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Biogas biorefineries are an innovative concept in the field of process engineering. As a process engineer, this is my first experience working with biogas biorefineries, and I am eager to explore and understand this subject in depth. This section will help us get acquainted with the basics and significance of biogas biorefineries within the industry.

Definition of Biogas Biorefineries

Biogas biorefineries use sophisticated, combined processes to convert organic waste, energy crops, and agricultural leftovers into biogas, biomethane, and valuable bio-based products through anaerobic digestion.

Biorefineries of biogas may include the following type:

  • Biogas biorefineries focusing on the production of biogas and fertilizers using energy crops or waste substrates like food waste or food production waste
  • Sugar crop biorefineries based on sugar beet, sugar cane, etc.
  • Starch crop biorefineries based on cereals, maize, potato, etc.
  • Green biorefineries based on wet biomass like grass, clover, etc.
  • Biorefineries that process all kinds of organic waste, including municipal, food industry, restaurant, and grocery store waste.

Typical Process of Biogas Biorefineries

Typical process of biogas biorefineries is shown below. Read More

Evaluating Performance Characteristics of Cooling Towers

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In this post I want to share with you how to evaluate performance characteristics of cooling towers. The performance characteristics of various types of towers will vary depending on height, fill configuration, and flow arrangement. Please be noted that this post is for basic knowledge only. Accurate characteristics of specific tower performance should be consulted with cooling tower manufacturer.

This post will cover the following performance characteristics of cooling tower:

  • Effect of varying wet bulb temperature on cold water temperature
  • Effect of varying cooling range on cold water temperature
  • Effect of varying water circulating rate and heat load on cold water temperature
  • Effect of varying wet bulb temperature, range, and water circulating rate on cold water temperature
  • Effect of varying fan HP (horsepower) input on cold water temperature

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Application and Selection of Flow Measurement

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In this post I want to share with you application and selection and flow measurement. In my career as process engineer, this is a very important topic since we always need to consider why we select this type of flow meter and not the other one.

Key Process in Selection of Flow Measurement

At least there are two key processes in selection of flow measurements. First, select meters that meet measurement requirements and are available in the needed size and materials. Then, evaluate cost, delivery, performance, and other factors to choose the best option.

Next, focus on key performance requirements like maximum allowable error (as a percentage of reading or full scale) and metering range. Use these limits to determine the needed rangeability—the ratio between maximum and minimum flow within acceptable error—and select appropriate flow sensor types.

Flow Measurement Application

Table below shows flow measurement applications of several types of flow sensors. Read More