Our Environmental Policy can be viewed here
The combination of pollution abatement technologies applied at this plant coupled with the carefully selected range of domestic coals ensure the plant’s compliance with the more stringent Indonesian legislative limits on nitrogen oxide (NOx), sulfur oxide (SOx) and particulate emissions which came into force in the year 2000.
The Indonesian sub-bituminous coals contracted for supply to Paiton II are characterised by high volatility and low nitrogen content. These two characteristics ensure excellent ‘low NOx’ combustion performance is achievable from the multi-layer overfire system installed.
NOx emissions are maintained below 370mg/Nm3.
Sulfur dioxide (SO2) emissions are a function of the sulphur content of the fuel since, effectively, all the sulphur contained in the coal is emitted in the flue gas, with the exception of a very small proportion which is retained in the ash. For each tonne of sulphur contained in the fuel, two tonnes of SO2 are formed. SO2 may be removed before the flue gas is discharged to the atmosphere by a process called Flue Gas Desulphurisation (FGD).
The seawater washing process represents a relatively recent development of FGD technology, combining the benefits of high sulphur removal efficiency at lower costs than more conventional limestone-gypsum based alternatives. The process relies on the natural alkalinity of raw seawater to remove the SO2 and Sulfur trioxide (SO3) from the gases, producing predominantly sulphite ions in solution. Air passed through the liquor subsequently serves to oxidise the sulphites to the sulphate form. Seawater is then added downstream of the absorber to increase the pH of the solution prior to discharge to the sea. The process does not require the quarrying, supply and transport of a solid reagent or the transport and disposal of a by-product.
The seawater washing FGD plant installed at Paiton II is one of the largest in the world. The FGD plant is designed to remove approximately 94% of the SO2 contained within the flue gases, ensuring the ability to meet the EPC contract specified limits, equivalent to 130mg/Nm3, when firing coals containing up to 0.69% sulphur.
Unless controlled, a significant proportion of the inert components of coal would be discharged to the atmosphere as particulate. There are a number of processes applicable to utility plant for limiting particulate emissions to very low levels prior to discharge of the flue-gas to the atmosphere. Of these, Electrostatic Precipitation (ESP) offers competitive advantages through life cost, high reliability, low pressure drop and high removal efficiency and represents the largest share of the utility market.
In the electrostatic precipitation process the dust laden gases are passed between collection plates and discharge electrodes. The discharge electrodes are centred between adjacent plates and provide a negative charge to the surrounding dust particles. The negatively charged dust particles are then collected on the positively earthed collector plates. The dust collected on the plates is periodically dislodged with the assistance of a rapping system and collected in hoppers below the plates.
The electrostatic precipitators installed at Paiton II have a design dust removal efficiency of approximately 99.5%, sufficient to ensure that dust emissions are maintained below 50mg/Nm3 even when firing the highest ash content coals.
The table below compares the Indonesian emissions standards for coal-fired plants with the Paiton II power plant environmental performance.
|Emissions||Indonesian Standards Since Year 2000||Paiton II
Power Station Specification
|NOx||850 mg/Nm3||370 mg/Nm3||-56%|
|SOx||750 mg/Nm3||130 mg/Nm3||-83%|
|Dust||150 mg/Nm3||50 mg/Nm3||-67%|
PROPER is an environmental performance rating program organised by the Indonesian Ministry of Living Environment & Forestry (KLHK) which is aimed at improving compliance and awareness of companies in environmental management. The mechanism of PROPER is to distribute information regarding levels of environmental compliance and performance of companies to society and stakeholders (public information disclosure).
There are five (5) rating categories under PROPER, namely: Black, Red, Blue, Green and Gold with Gold being the highest award. Red and Black Ratings are given to companies which do not comply with the prevailing environmental laws and legislation. Green and Gold Ratings are awarded to companies which are fully compliant with the applicable laws and legislation, doing “beyond compliance” efforts and also demonstrate their commitment in community development and Corporate Social Responsibility (CSR).
In 2016, Jawa Power received the second PROPER Gold Award, after the first one in 2013. Jawa Power remains the only coal-fired power station in Indonesia which is classified Gold Rating.