angle

bacteria

big

bio

boiler

building

business

chemical

chlorine

clean

company

construction

device

dry

ecology

electric

electricity

energy

engine

engineering

equipment

facility

factory

filter

flocculation

fuel

gas

generation

generator

heat

heavy

huge

indoor

industrial

industry

iron

line

machine

manufacturing

metal

modern

natural

oil

organic

pan

panorama

petroleum

pipe

pipeline

piping

plant

pollution

power

process

production

purification

purified

reservoir

sedimentation

stainless

station

steel

storage

store

structure

supply

system

tank

technical

technology

thermal

tool

treatment

tube

turbine

valve

wide