Technical Writing

Process Paragraph

The processes involved in sewage disposal are usually classified into three stages.
First, sewage is carried from its source to settling tank through main sewer. In the settling tank, solid wastes settle at the bottom while wastewater passes through. Solid wastes which are unable to decay will be removed and burned later.
Next, wastewater from the settling tank is transferred to the pump house for preparation of the next process.
Finally, wastewater from the pump house is pumped to brickwork called sprinkler beds which consist of rotating arms, jets, and filters. Wastewater is forcefully flowed by jets on the rotating arms to get rid of smaller solids that disperse throughout it. To intensify the purity of the water, out of the rotating arms wastewater stream is distributed intermittently over filters. This way, stones and microorganism will not be able to pass; therefore, water that passes the filtration process is free from contaminations and ready to enter the river.

The process of extracting methane gas from household waste requires five steps.
The first step is warming bed, in which household waste is put and warmed to stimulate the decomposition process. Decomposition of waste produces component that contains nutrient necessary for plants, known as fertilizer, and marsh gas composed of hydrogen and carbon, known as methane.
After methane gas is acquired, it is carried to dirt trap. In dirt trap, dirt that dissolves in methane is removed through release cap.
Next, methane is flowed to gas indicator which contains water. The gas indicator has sealed top, hence methane gas will pop up as bubbles in the water. This step is useful for indicating whether there really is methane gas or not.
If previous step shows that methane gas truly exists, then the methane gas is transferred through pipe to a pressure releasing apparatus. The apparatus is a tube shaped object that has no cap and contains water. Mouth of the pipe is put 8 cm below the water surface, thus releasing the pressure from methane.
Finally, methane is passed to the gas holder where inner tubes and weight is used to increase gas pressure. After passing the inner tubes, the whole steps of extracting methane gas from household waste is completed, and methane is ready to be used as fuel and substance for producing other valuable chemicals.

Very good.

posted by Tania Krisanty @ 9:54 AM